| infection of rhesus and cynomolgus macaques with a rapidly fatal siv (sivsmm/pbj) isolate from sooty mangabeys. | a variant of simian immunodeficiency virus (sivsmm/pbj), isolated from a chronically infected pig-tailed macaque has been shown in previous studies to produce acutely fatal disease uniformly in pig-tailed macaques and in some rhesus macaques. the present study extends investigation of sivsmm/pbj pathogenesis in rhesus and cynomolgus monkeys. cynomolgus and rhesus macaques were found to be uniformly susceptible to infection, but as previously reported, the rhesus were found to not be uniform in t ... | 1992 | 1457209 |
| infection of macaca nemestrina by human immunodeficiency virus type-1. | after observations that macaca nemestrina were exceptionally susceptible to simian immunodeficiency virus and human immunodeficiency virus type-2 (hiv-2), studies of hiv-1 replication were initiated. several strains of hiv-1, including a recent patient isolate, replicated in vitro in peripheral blood mononuclear cells (pbmcs) and in cd4-positive m. nemestrina lymphocytes in a cd4-dependent fashion. eight animals were subsequently inoculated with either cell-associated or cell-free suspensions of ... | 1992 | 1621083 |
| method for detection of simian immunodeficiency virus neutralizing antibodies using a noncommercial antigen capture enzyme-linked immunosorbent assay. | a neutralization test (nt) using a noncommercial antigen capture enzyme-linked immunosorbent assay (elisa) to detect simian immunodeficiency virus (siv) growth in vitro was developed. the capture antibody was a mixture of purified macaque anti-siv immunoglobulin g (igg) and a monoclonal antibody to siv p27. captured antigens were detected by using purified macaque anti-siv igg conjugated to horseradish peroxidase. the nt reliably and sensitively detected differences when various amounts of siv w ... | 1992 | 1624558 |
| genetic differences accounting for evolution and pathogenicity of simian immunodeficiency virus from a sooty mangabey monkey after cross-species transmission to a pig-tailed macaque. | we determined the nucleotide sequences of two related isolates of simian immunodeficiency virus from the sooty mangabey monkey (sivsmm) that exhibit dramatic differences in virulence. these isolates are separated by one experimental cross-species transmission, from sooty mangabey to pig-tailed macaque. the parental virus (sivsmm9), nonpathogenic in the original host (sooty mangabeys), causes a chronic aids-like disease in macaques. in contrast, the variant virus (sivsmmpbj14) induces an acute le ... | 1992 | 1727495 |
| replication of an acutely lethal simian immunodeficiency virus activates and induces proliferation of lymphocytes. | a variant of simian immunodeficiency virus from sooty mangabey monkeys (sivsmm), termed sivsmmpbj14, was previously identified and shown to induce acute disease and death within 1 to 2 weeks of inoculation of pig-tailed macaques and mangabey monkeys (p. n. fultz, h. m. mcclure, d. c. anderson, and w. m. switzer, aids res. hum. retroviruses 5:397-409, 1989). sivsmmpbj14 differed from its parent virus, sivsmm9, not only in pathogenicity but also in multiple in vitro properties. as a first approach ... | 1991 | 1870205 |
| sequence analysis and acute pathogenicity of molecularly cloned sivsmm-pbj14. | the pbj14 isolate of simian immunodeficiency virus from sooty mangabey monkeys (sivsmm-pbj14) is the most acutely pathogenic primate lentivirus so far described, always causing fatal disease in pig-tailed macaques (macaca nemestrina) within 8 days of inoculation. as a first step in identifying viral genes and gene products that influence pathogenicity, the sivsmm-pbj14 genome was amplified by the polymerase chain reaction as 5' and 3' genomic halves of 5.1 and 5.8 kilobases, respectively, and mo ... | 1990 | 1971917 |
| inoculation of macaca fascicularis with simian immunodeficiency virus, sivmne immunologic, serologic, and pathologic changes. | previous studies had tested the susceptibility of two macaque species, macaca nemestrina and m. mulatta, to infection with the primate lymphotropic lentivirus sivmne. in this report we describe the results obtained after infecting eleven m. fascicularis with sivmne. six of the animals had previously been immunized with a recombinant vaccinia virus expressing the envelope gene of hiv-1. all eleven animals became seropositive. to date ten animals have died 43 to 155 weeks post infection of an aids ... | 1990 | 2231689 |
| transmission of the simian immunodeficiency virus sivmne in macaques and baboons. | a primate lymphotropic lentivirus was isolated on hut 78 cells after cocultivation of a lymph node from a macaque that died with malignant lymphoma. in earlier studies siv/mne was inoculated into 17 macaques and two baboons. all of the macaques became viremic and seropositive. fifteen of the macaques succumbed to a classic aids-like disease, whereas the baboons did not become viremic. the siv/mne virus has now been molecularly cloned and inoculated into macaca nemestrina and baboons. a new trans ... | 1989 | 2547959 |
| molecularly cloned simian immunodeficiency virus sivagm3 is highly divergent from other sivagm isolates and is biologically active in vitro and in vivo. | simian immunodeficiency viruses have been isolated from african green monkeys originating from ethiopia. a molecular clone, termed sivagm3, was found to be highly divergent from sivagmtyo-1 in terms of its restriction map and partial nucleotide sequence. a premature stop codon present in the transmembrane protein of sivagm tyo-1 was absent in sivagm3. sivagm3 was biologically active in vitro and in vivo and displayed characteristics reminiscent of the wild-type virus. biological activity was dem ... | 1989 | 2685353 |
| identification and biologic characterization of an acutely lethal variant of simian immunodeficiency virus from sooty mangabeys (siv/smm). | a virus pool isolated from lymphoid tissue of a macaque (pbj) infected for 14 months with siv/smm was found to be associated with acute disease and death. six of six pig-tailed macaques, one of three rhesus macaques, and three of four siv/smm-seronegative mangabeys developed acute disease within 5 days and died from 7 to 13 days postinoculation; however, neither of two siv/smm-infected mangabeys died or developed disease. the virus associated with acute disease and death was shown by electron mi ... | 1989 | 2765298 |
| inoculation of baboons and macaques with simian immunodeficiency virus/mne, a primate lentivirus closely related to human immunodeficiency virus type 2. | a primate lymphotropic lentivirus was isolated on the human t-cell line hut 78 after cocultivation of a lymph node from a pig-tailed macaque (macaca nemestrina) that had died with malignant lymphoma. this isolate, originally designated m. nemestrina immunodeficiency virus (mniv) and now classified as simian immunodeficiency virus (siv/mne), was inoculated intravenously into three juvenile rhesus monkeys (macaca mulatta), three juvenile pig-tailed macaques (m. nemestrina), and two juvenile baboon ... | 1988 | 3285032 |
| molecular characterization of gag proteins from simian immunodeficiency virus (sivmne). | a simian immunodeficiency virus (siv) designated sivmne was isolated from a pig-tailed macaque with lymphoma housed at the university of washington regional primate research center, seattle. to better establish the relationship of sivmne to other immunodeficiency viruses, we purified and determined the partial amino acid sequences of six structural proteins (p1, p2, p6, p8, p16, and p28) from sivmne and compared these amino acid sequences to the translated nucleotide sequences of sivmac and huma ... | 1988 | 3292789 |
| nucleotide sequence of the hiv-2 eho genome, a divergent hiv-2 isolate. | the hiv-2 eho isolate from cote d'ivoire has been characterized as a highly cytopathic hiv-2 strain, which can be differentiated from other isolates by the smaller size of its external envelope glycoprotein. the entire nucleotide sequence (10,352 bp) of the hiv-2 eho genome is filed in the embl/genbank data libraries under accession no. u27200. despite its high degree of variability, the genetic organization of hiv-2 eho was found to be similar to other hiv-2 and simian immunodeficiency virus ... | 1995 | 7546916 |
| intrarectal inoculation of macaques by the simian immunodeficiency virus, sivmne e11s: cd4+ depletion and aids. | macaca nemestrina and macaca fascicularis were inoculated with various doses of a single-cell clone of sivmne-infected hut 78 cells (e11s) by both the intravenous and intrarectal routes. animals inoculated intravenously at each dose seroconverted and virus was isolated from peripheral blood mononuclear cells, but only the high-dose intrarectally exposed macaques became viremic and seroconverted. however, some seronegative, virus isolation negative intrarectally inoculated macaques showed evidenc ... | 1994 | 7731030 |
| comparison of rates of intracellular metabolism of zidovudine in human and primate peripheral blood mononuclear cells. | 3'-azido-3'-deoxythymidine (azt) is a drug of choice for the treatment of aids. on the basis of pharmacokinetic data, the nonhuman primate macaca nemestrina has been shown to be a suitable animal model for use in the study of the disposition of azt. however, since azt is activated to its metabolite, the azt triphosphate (azttp), intracellularly, we investigated the intracellular activation of azt in peripheral blood mononuclear cells (pbmcs) of healthy and simian immunodeficiency virus-infected ... | 1994 | 7840577 |
| the u3 promoter region of the acutely lethal simian immunodeficiency virus clone smmpbj1.9 confers related biological activity on the apathogenic clone agm3mc. | infection with the acutely pathogenic molecular virus clone sivsmmpbj1.9, cloned from isolate pbj14 of simian immunodeficiency virus (siv) from sooty mangabey monkeys (cercocebus atys), leads to acute viral and often lethal disease within days or weeks. sivsmmpbj1.9 has the unique property of replicating in nonstimulated peripheral blood mononuclear cells from pig-tailed macaques. in contrast, molecular virus clone sivagm3mc of siv from african green monkeys (cercopithecus aethiops), which is ap ... | 1995 | 7877983 |
| molecular and biological analyses of quasispecies during evolution of a virulent simian immunodeficiency virus, sivsmmpbj14. | a prototypic simian immunodeficiency virus (sivsmm9), isolated from a naturally infected sooty mangabey (cercocebus atys), was passaged in vivo in a pig-tailed macaque (macaca nemestrina) having the identifier pbj. when pbj died of a typical aids-like syndrome 14 months after infection, the virus isolated from its tissues was subsequently shown to differ from sivsmm9 genetically and biologically. most notably, this isolate, sivsmmpbj14 (siv-pbj14), is the most virulent primate lentivirus known: ... | 1995 | 7884848 |
| an acutely lethal simian immunodeficiency virus stimulates expansion of v beta 7- and v beta 14-expressing t lymphocytes. | sivsmmpbj14, a variant simian immunodeficiency virus isolated from a pig-tailed macaque, stimulates the proliferation of macaque t lymphocytes in vitro and induces an acutely lethal disease in macaques characterized, in part, by lymphadenopathy and splenomegaly. to determine whether sivsmmpbj14 exhibits superantigen-like activity, in vitro and in vivo studies of t-cell receptor v beta repertoire were undertaken using pcr-based quantitative methods. whereas in vitro phytohemagglutinin stimulation ... | 1994 | 7914369 |
| viral genetic determinants in sivsmmpbj pathogenesis. | a variant simian immunodeficiency virus (siv) from sooty mangabeys, sivsmmpbj, induces an acutely lethal disease in pigtailed macaques (macaca nemestrina). this study further characterizes the viral genetic determinants involved in this acutely lethal disease. we have generated chimeric molecular clones constructed between sivsmmpbj and either sivsmh4 or sivsmm9 to analyze the role of the 5' half of the genome and the envelope gene in the induction of acute disease. these studies suggest that th ... | 1994 | 7966228 |
| infectivity of titered doses of simian immunodeficiency virus clone e11s inoculated intravenously into rhesus macaques (macaca mulatta). | the macaque infectious dose (mid) of a single-cell clone of simian immunodeficiency virus isolated from a pig-tailed macaque (siv/mne clone e11s) was determined in rhesus macaques (macaca mulatta). twenty-one macaques were inoculated with 10-fold dilutions of the virus stock (three or four animals per dose). the virologic and clinical status of these animals was monitored for 26 weeks. the 25% mid (mid25) occurred at a 10(5)-fold dilution of the viral stock. | 1994 | 7966238 |
| immune activation and viral burden in acute disease induced by simian immunodeficiency virus sivsmmpbj14: correlation between in vitro and in vivo events. | the simian immunodeficiency virus sivsmmpbj14 (siv-pbj14) is an atypical lentivirus that causes acute disease and death in pig-tailed macaques and in vitro replicates efficiently in resting macaque lymphocytes and activates and induces proliferation of lymphocytes. the present study was conducted to test the hypothesis that production of large quantities of siv-pbj14 induces widespread immune activation and elaboration of cytokines which lead directly to the death of infected pig-tailed macaques ... | 1994 | 8057436 |
| acute infection of macaca nemestrina by human immunodeficiency virus type 1. | the pigtail macaque (macaca nemestrina) has a marked sensitivity to infection by simian immunodeficiency virus and human immunodeficiency virus type 2 (hiv-2). on this basis, we previously studied this species' susceptibility to hiv-1 and demonstrated infection in six macaques inoculated with either cell-associated hiv-1 or cell-free virus alone. this report expands upon our initial in vitro and in vivo findings. five laboratory-adapted and one primary clinical strain of hiv-1 replicated in vitr ... | 1993 | 8101673 |
| spontaneous substitutions in the vicinity of the v3 analog affect cell tropism and pathogenicity of simian immunodeficiency virus. | simian immunodeficiency virus (siv) exists within tissues of infected macaques as a mixture of diverse genotypes. the goal of this study was to investigate the biologic significance of this variation in terms of cellular tropism and pathogenicity. pcr was used to amplify and clone 3'-half genomes from the spleen of an immunodeficiency siv-infected pig-tailed macaque (macaca nemestrina). eight infectious clones were generated by ligation of respective 3' clones into a related sivsm 5' clone, and ... | 1994 | 8139042 |
| simian immunodeficiency virus sivsmmpbj 1.9 induces multinucleated giant cell formation in human peripheral blood monocytes. | sivsmmpbj 1.9 is an extremely virulent clone of the simian immunodeficiency virus sivsmmpbj 14 that causes an acute lethal disease in pigtail macaques, with death occurring 6 to 8 days after infection. the disease is characterized by bloody mucoid diarrhea, lymphoid hyperplasia, and giant cell pneumonia. we have developed an in vitro model for the production of multinucleated giant cells (mgcs) in which peripheral blood monocytes rapidly fuse to form mgcs when cultured in lymphocyte-conditioned ... | 1994 | 8179965 |
| in vitro susceptibility of macaca nemestrina to human herpesvirus 6: a potential animal model of coinfection with primate immunodeficiency viruses. | human herpesvirus 6 (hhv-6), a lymphotropic herpesvirus, has been suggested as a potential cofactor in the acquired immunodeficiency syndrome (aids). previous studies indicate that hhv-6 has a restricted range of susceptible species. in this study, we tested the in vitro susceptibility to hhv-6 of macaca nemestrina (pig-tailed macaque), a species that has been found to be infectable by human immunodeficiency virus type i in vivo and that develops an aids-like syndrome following simian immunodefi ... | 1994 | 8198870 |
| genetic variation of the sivagm transmembrane glycoprotein in naturally and experimentally infected primates. | an in-frame stop codon prematurely truncating the transmembrane glycoprotein (tmp) is a common feature of many simian immunodeficiency virus, african green monkey strain (sivagm) molecular clones. the purpose of this study was to investigate the native form of the sivagm tmp in a naturally infected african green monkey (agm) and to study the fate of the stop codon following the passage of sivagm in primates. | 1993 | 8397939 |
| multiple viral determinants contribute to pathogenicity of the acutely lethal simian immunodeficiency virus sivsmmpbj variant. | simian immunodeficiency virus (siv) induces an immunodeficiency syndrome similar to human aids. although the disease course of siv-induced immunodeficiency is generally measured in months to years, a disease syndrome that results in death in 5 to 14 days has been described in pig-tailed macaques infected with the sivsmmpbj (pbj) strain. the purpose of this study was to derive an acutely lethal pbj molecular clone in order to study viral genes involved in pathogenesis. six infectious molecular cl ... | 1993 | 8474153 |
| protection against lethal simian immunodeficiency virus sivsmmpbj14 disease by a recombinant semliki forest virus gp160 vaccine and by a gp120 subunit vaccine. | infection of pigtail macaques with sivsmmpbj14, biological clone 3 (siv-pbj14-bc13), produces an acute and usually fatal shock-like syndrome 7 to 14 days after infection. we used this simian immunodeficiency virus (siv) model as a rapid and rigorous challenge to evaluate the efficacy of two siv env vaccine strategies. groups of four pigtail macaques were immunized four times over a 25-week span with either a recombinant semliki forest virus expressing the siv-pbj14 env gp160 (sfv-sivgp160) or pu ... | 1996 | 8627721 |
| chimeric simian/human immunodeficiency virus that causes progressive loss of cd4+ t cells and aids in pig-tailed macaques. | by animal-to-animal passage of simian/human immunodeficiency virus (shiv) in pig-tailed macaques, we have developed a macaque model of human immunodeficiency virus type 1 (hiv-1) disease in humans. passaging was begun with a chimeric virus containing the env gene of hiv-1 hxbc2 and the gag and pol genes of simian immunodeficiency virus sivmac239. shiv was passaged serially in cohorts of two macaques each, using bone marrow-to-bone marrow transfers at 5, 5, and 16 weeks for passages 2, 3, and 4, ... | 1996 | 8627799 |
| requirements for lymphocyte activation by unusual strains of simian immunodeficiency virus. | when residues 17 and 18 in nef of simian immunodeficiency virus strain sivmac239 were changed from rq to ye, the resultant virus was able to replicate in peripheral blood mononuclear cell cultures without prior lymphocyte activation and without the addition of exogenous interleukin-2, caused extensive lymphocyte activation in these cultures, and produced an acute disease in rhesus and pigtail macaques (z. du, s. m. lang, v. g. sasseville, a. a. lackner, p. 0. ilyinskii, m. d. daniel, j. u. jung, ... | 1996 | 8648760 |
| deletion of the nef gene abrogates the ability of siv smmpbj to induce acutely lethal disease in pigtail macaques. | simian immunodeficiency virus (siv) infection in macaque species is typically associated with the development of a progressive immunodeficiency disease, similar to human aids, resulting in death of animals in months to years after infection. in contrast, a variant virus, termed sivsmmpbj, induces an acute disease in macaques, resulting in death in 5 to 14 days after infection. previously, we have shown that several viral determinants contribute to the pathogenesis of this disease. the present st ... | 1996 | 8744583 |
| phylogeny and natural history of the primate lentiviruses, siv and hiv. | studies of primate lentivirus phylogeny over the past decade have established a minimum of five related, but genetically distinct, groups of simian immunodeficiency virus (siv), each originating from a different african primate species. the hypothesis that hiv-2 (and sivmac) arose by cross-species transmission from sooty mangabeys (cercocebus atys has been strengthened by a more detailed characterization of the sivsm/sivmac/hiv-2 group of viruses. siv from all four subspecies of african green mo ... | 1995 | 8745080 |
| receptor function of cd4 structures from african green monkey and pig-tail macaque for simian immunodeficiency virus, sivsm, sivagm, and human immunodeficiency virus type-1. | differences in kinetics of infection, cellular tropism, and cytopathology of siv and hiv appear to depend on both viral and host factors. we investigated the role of critical cd4 structures from african green monkeys (agm) a natural siv host, from pig-tailed macaques (pt) an unnatural siv host, and from humans, as well as the role of species-specific cellular factors involved in the tropism, kinetics of infection, and cytopathic effects of several siv and hiv-1. critical regions of the pt macaqu ... | 1995 | 8833265 |
| [progress in vaccination against aids]. | two vaccination trials against aids viruses are reported. the first trial was a prophylactic vaccination carried out in the pig-tailed macaque (macacca nemestrina) against simian immunodeficiency virus (siv) variant pbj14. the immunogen was a semliki forest virus (sfv) recombinant expressing sfv - pbj14 envelope protein. vaccination did not prevent infection but protected the animals against the disease (a fulminant form of aids that kills the animal within 12-15 days). the second trial was a th ... | 1995 | 8845793 |
| a case of pulmonary cestodiasis in a simian immunodeficiency virus-infected pigtailed macaque (macaca nemestrina) in which virus-infected leukocytes are present within the lesion. | the larvae of mesocestoides are rarely encountered in nonhuman primates, with most cases reported in baboons. infection of macaques has been occasionally diagnosed, but mesocestoides in the lung parenchyma is extremely rare. we have previously demonstrated that in macaques with terminal aids, simian immunodeficiency virus (siv)-infected leukocytes are rarely found in cellular infiltrates associated with opportunistic infections or preexisting disease. here we describe larvae (tetrathyridia) of t ... | 1996 | 8906603 |
| a molecularly cloned, pathogenic, neutralization-resistant simian immunodeficiency virus, sivsme543-3. | an infectious molecular clone of simian immunodeficiency virus sivsm was derived from a biological isolate obtained late in disease from an immunodeficient rhesus macaque (e543) with siv-induced encephalitis. the molecularly cloned virus, sivsme543-3, replicated well in macaque peripheral blood mononuclear cells and monocyte-derived macrophages and resisted neutralization by heterologous sera which broadly neutralized genetically diverse siv variants in vitro. sivsme543-3 was infectious and indu ... | 1997 | 8995688 |
| animal model of mucosally transmitted human immunodeficiency virus type 1 disease: intravaginal and oral deposition of simian/human immunodeficiency virus in macaques results in systemic infection, elimination of cd4+ t cells, and aids. | chimeric simian/human immunodeficiency virus (shiv) consists of the env, vpu, tat, and rev genes of human immunodeficiency virus type 1 (hiv-1) on a background of simian immunodeficiency virus (siv). we derived a shiv that caused cd4+ cell loss and aids in pig-tailed macaques (s. v. joag, z. li, l. foresman, e. b. stephens, l. j. zhao, i. adany, d. m. pinson, h. m. mcclure, and o. narayan, j. virol. 70:3189-3197, 1996) and used a cell-free stock of this virus (shiv(ku-1)) to inoculate macaques b ... | 1997 | 9094679 |
| vaccine effect using a live attenuated nef-deficient simian immunodeficiency virus of african green monkeys in the absence of detectable vaccine virus replication in vivo. | immunization of adult macaques with live attenuated simian immunodeficiency viruses (sivs) lacking the nef genes has been shown to protect against challenge with full-length pathogenic siv. to test live attenuated virus vaccines for the first time in a natural host we have constructed a mutant siv from african green monkeys (sivagm) with a deletion of 125 bp in the nef gene (sivagm3 delta nef). this mutant showed moderately delayed in vitro replication in the t cell line molt-4/8 and in primary ... | 1997 | 9108105 |
| loss of the sivsmmpbj14 phenotype and nef genotype during long-term survival of macaques infected by mucosal routes. | the ability of the simian immunodeficiency virus sivsmmpbj14 (siv-pbj14) to activate and induce proliferation of quiescent peripheral blood lymphocytes from macaques is an in vitro correlate of its acutely lethal in vivo phenotype. siv-pbj14 differs from other siv strains by encoding tyrosine at amino acid 17 (y17) in nef, which generates an activation motif important for signal transduction. although intravenous inoculation of pig-tailed macaques with siv-pbj14 uniformly leads to death within 2 ... | 1997 | 9126264 |
| isolation of sooty mangabey simian t-cell leukemia virus type i [stlv-i(sm)] and characterization of a mangabey t-cell line coinfected with stlv-i(sm) and simian immunodeficiency virus sivsmmpbj14. | it has been postulated that dual infections of humans with human immunodeficiency virus (hiv) and human t-cell leukemia/lymphotropic virus (htlv) may potentiate disease progression. counterparts of both of these pathogenic human retroviruses have been identified in various simian species indigenous to asia and africa, including sooty mangabey monkeys (cercocebus atys). using peripheral blood mononuclear cells (pbmc) from a mangabey naturally infected with both siv and stlv-i, t-cell lines were e ... | 1997 | 9281507 |
| the cytopathicity of a simian immunodeficiency virus mne variant is determined by mutations in gag and env. | previous studies suggested that the rapidly replicating, highly cytopathic, syncytium-inducing (rapid-high/si) phenotype of simian immunodeficiency virus mne variants that evolved in macaques inoculated with a slowly replicating, minimally cytopathic, non-syncytium-inducing (slow-low/nsi) molecular clone was not solely the result of changes in the envelope surface protein (env su). to define the viral determinants responsible for the change in phenotype, we molecularly cloned a rapid-high/si var ... | 1997 | 9311845 |
| specific n-linked and o-linked glycosylation modifications in the envelope v1 domain of simian immunodeficiency virus variants that evolve in the host alter recognition by neutralizing antibodies. | during progression to aids in simian immunodeficiency virus (siv) mne-infected macaques, viral variants are selected that encode sequences with serine and threonine changes in variable region 1 (v1) of the surface component of the viral envelope protein (env-su). because these serine and threonine amino acid changes are characteristic of sites for o-linked and n-linked glycosylation, we examined whether they were targets for modification by carbohydrates. for this purpose, we used several bioche ... | 1997 | 9311856 |
| infection of macaca nemestrina neonates with hiv-1 via different routes of inoculation. | receptive anal intercourse but not orogenital sex has been identified as a major risk factor for transmission of hiv-1. recent studies using simian immunodeficiency virus (siv) in rhesus macaques have demonstrated relatively efficient infection following oral administration, indicating that modes of transmission may vary between hiv-1 and siv. here, we investigate whether hiv-1 infection of macaques via the oral route is more efficient than via the rectal route. | 1997 | 9365759 |
| a malignant astrocytoma containing simian virus 40 dna in a macaque infected with simian immunodeficiency virus. | polyomaviruses have proven oncogenicity in nonhost experimental animals; however, studies concerning the association between human brain tumors and simian and human polyomaviruses have yielded inconclusive results. we examined the relationship of sv40 to a malignant astrocytoma found in the right frontal lobe of a pigtail macaque (macaca nemestrina) infected with simian immunodeficiency virus (siv). consistent with the histologic diagnosis, the tumor was immunoreactive with antibodies to s-100 p ... | 1997 | 9379484 |
| a lymph node-derived cytopathic simian immunodeficiency virus mne variant replicates in nonstimulated peripheral blood mononuclear cells. | lymph nodes (lns) are sites of active human immunodeficiency virus type 1 (hiv-1) and simian immunodeficiency virus (siv) replication and disease at both early and late stages of infection. consequently, variant viruses that replicate efficiently and subsequently cause immune dysfunction may be harbored in this tissue. to determine whether ln-associated sivs have an increased capacity to replicate and induce cytopathology, a molecular clone of siv was isolated directly from dna extracted from un ... | 1998 | 9420221 |
| the u3 promoter and the nef gene of simian immunodeficiency virus (siv) smmpbj1.9 do not confer acute pathogenicity upon sivagm. | two chimeric proviruses comprising the u3 promoter and the nef gene of simian immunodeficiency virus (siv) smmpbj1.9 in addition to other genomic regions of sivagm3mc from african green monkeys (cercopithecus aethiops) were constructed. the derived chimeric viruses (sivagm3mc/sivsmmpbj1.9) were both able to replicate in nonstimulated peripheral blood leukocytes from pig-tailed macaques (macaca nemestrina), a biological property often correlated with acute pathogenicity. however, only one of the ... | 1998 | 9525679 |
| simian-human immunodeficiency virus (shiv) containing the nef/long terminal repeat region of the highly virulent sivsmmpbj14 causes pbj-like activation of cultured resting peripheral blood mononuclear cells, but the chimera showed no increase in virulence. | sivsmmpbj14 is a highly pathogenic lentivirus which causes acute diarrhea, rash, massive lymphocyte proliferation predominantly in the gastrointestinal tract, and death within 7 to 14 days. in cell culture, the virus has mitogenic effects on resting macaque t lymphocytes. in contrast, sivmac239 causes aids in rhesus macaques, generally within 2 years after inoculation. in a previous study, replacement of amino acid residues 17 and 18 of the nef protein of sivmac239 with the corresponding amino a ... | 1998 | 9573293 |
| the tyrosine-17 residue of nef in sivsmmpbj14 is required for acute pathogenesis and contributes to replication in macrophages. | the variant simian immunodeficiency virus termed sivsmmpbj14 induces a rapidly fatal disease in pig-tailed macaques. the acute pathogenic effects of this virus appear to be associated with at least two in vitro characteristics: the ability to induce lymphocyte proliferation; and the ability to replicate in unstimulated pbmc. two of the amino acids in nef of pbj14 (the no. 17 residue, tyrosine, and the no. 18 residue, glutamic acid) appear to be linked to the virus' ability to induce lymphocyte a ... | 1998 | 9601497 |
| viral genetic evolution in macaques infected with molecularly cloned simian immunodeficiency virus correlates with the extent of persistent viremia. | genetic evolution of the simian immunodeficiency virus (siv) envelope glycoprotein was evaluated in a group of six macaques (macaca nemestrina) infected with the molecularly cloned, moderately pathogenic sivsm62d. the extent of envelope evolution was subsequently evaluated within the context of the individual pattern of viremia and disease outcome. two macaques in this cohort developed aids by 1.5 years postinoculation (progressors), whereas the remaining four macaques remained asymptomatic (non ... | 1998 | 9658091 |
| down-modulation of the zap-70 protein tyrosine kinase in macaque t lymphocytes infected with sivsmmpbj14. | the simian immunodeficiency virus siv-pbj14 is the most virulent primate lentivirus identified to date. other siv strains, including the parental sivsmm9, require mitogen-activated peripheral blood mononuclear cells (pbmc) for replication in vitro; however, siv-pbj14 replicates in quiescent pig-tailed macaque pbmc and induces cellular proliferation, consistent with its in vivo pathogenesis. to identify mechanisms involved in siv-pbj14-induced t-cell proliferation, kinases important in early t-ce ... | 1998 | 9747955 |
| isolation and characterization of a neuropathogenic simian immunodeficiency virus derived from a sooty mangabey. | transfusion of blood from a simian immunodeficiency virus (siv)- and simian t-cell lymphotropic virus-infected sooty mangabey (designated fgb) to rhesus and pig-tailed macaques resulted in the development of neurologic disease in addition to aids. to investigate the role of siv in neurologic disease, virus was isolated from a lymph node of a pig-tailed macaque (designated pgm) and the cerebrospinal fluid of a rhesus macaque (designated ron2) and passaged to additional macaques. siv-related neuro ... | 1998 | 9765429 |
| nucleocapsid protein zinc-finger mutants of simian immunodeficiency virus strain mne produce virions that are replication defective in vitro and in vivo. | all retroviruses (except the spumaretroviruses) contain a nucleocapsid (nc) protein that encodes one or two copies of the zn2+-finger sequence -cys-x2-cys-x4-his-x4-cys-. this region has been shown to be essential for recognition and packaging of the genomic rna during virion particle assembly. additionally, this region has been shown to be involved in early infection events in a wide spectrum of retroviruses, including mammalian type c [e.g., murine leukemia virus (mulv)], human immunodeficienc ... | 1999 | 9918884 |
| coinfection of macaques with simian immunodeficiency virus and simian t cell leukemia virus type i: effects on virus burdens and disease progression. | to test the hypothesis that coinfection with human immunodeficiency virus (hiv) and human t cell leukemia/lymphoma virus types i or ii (htlv-i or -ii) accelerates progression to aids, pig-tailed macaques were inoculated with the simian counterparts, siv and stlv-i. during 2 years of follow-up of singly and dually infected macaques, no differences in siv burdens, onset of disease, or survival were detected. however, in the first coinfected macaque that died of aids (1 year after infection), >50% ... | 1999 | 9952366 |
| virus threshold determines disease in sivsmmpbj14-infected macaques. | simian immunodeficiency virus (siv) variant sivsmmpbj14 is unique in producing an acutely lethal enteropathic syndrome in pigtail macaques. to determine whether the nature of the pbj14 disease would be attenuated by decreasing virus input and to relate tissue virus burden to the severity of disease, we infected pigtail macaques with serial 10-fold doses of sivsmmpbj14 clone bcl.3 spanning 10(-2) through 10(4)tcid50. the results revealed a strikingly narrow difference between minimum infectious a ... | 1999 | 10029250 |
| in vivo cell and tissue tropism of sivsmmpbj14-bcl.3. | to gain insight into the unique pathogenicity of simian immunodeficiency virus (siv) variant pbj14, which produces an acutely lethal enteropathic syndrome in infected pigtail macaques, we investigated the cell and tissue tropisms of a highly pathogenic biologic clone (bcl.3) of sivsmmpbj14. to compare the relative amount of viral antigen in lymphoid organs of infected macaques we used an objective semiquantitative immunohistochemistry (sqihc) assay. we found that in all animals viral antigen loa ... | 1999 | 10029252 |
| pathogenicity and comparative evolution in vivo of the transitional quasispecies sivsmmpbj8. | during 14 months of infection of a pig-tailed macaque, the acutely lethal simian immunodeficiency virus sivsmmpbj14 (siv-pbj14) evolved from the minimally pathogenic strain sivsmm9. the virus isolated at 8 months (siv-pbj8) exhibited properties of both sivsmm9 and siv-pbj14, indicating that a phenotypic transition occurred between 6 and 10 months. to assess the influence that this new composition of biologic properties might have on pathogenicity, three pig-tailed macaques were inoculated intrav ... | 1999 | 10364501 |
| postinoculation pmpa treatment, but not preinoculation immunomodulatory therapy, protects against development of acute disease induced by the unique simian immunodeficiency virus sivsmmpbj. | the fatal disease induced by sivsmmpbj4 clinically resembles endotoxic shock, with the development of severe gastrointestinal disease. while the exact mechanism of disease induction has not been fully elucidated, aspects of virus biology suggest that immune activation contributes to pathogenesis. these biological characteristics include induction of peripheral blood mononuclear cell (pbmc) proliferation, upregulation of activation markers and fas ligand expression, and increased levels of apopto ... | 1999 | 10482616 |
| experimental infection of rhesus and pig-tailed macaques with macaque rhadinoviruses. | the recognition of naturally occurring rhadinoviruses in macaque monkeys has spurred interest in their use as models for human infection with kaposi sarcoma-associated herpesvirus (human herpesvirus 8). rhesus macaques (macaca mulatta) and pig-tailed macaques (macaca nemestrina) were inoculated intravenously with rhadinovirus isolates derived from these species (rhesus rhadinovirus [rrv] and pig-tailed rhadinovirus [prv]). nine rhadinovirus antibody-negative and two rhadinovirus antibody-positiv ... | 1999 | 10559350 |
| high viral load in the cerebrospinal fluid and brain correlates with severity of simian immunodeficiency virus encephalitis. | aids dementia and encephalitis are complications of aids occurring most frequently in patients who are immunosuppressed. the simian immunodeficiency virus (siv) model used in this study was designed to reproducibly induce aids in macaques in order to examine the effects of a neurovirulent virus in this context. pigtailed macaques (macaca nemestrina) were coinoculated with an immunosuppressive virus (siv/deltab670) and a neurovirulent molecularly cloned virus (siv/17e-fr), and more than 90% of th ... | 1999 | 10559366 |
| the disruption of macaque cd4+ t-cell repertoires during the early simian immunodeficiency virus infection. | t-cell receptor (tcr) complementarily determining region 3 (cdr3) spetratyping analysis was employed to assess the ability of an aids virus to disrupt cd4 + t-cell repertoires during the primary infection. rhesus and pig-tailed macaques infected with simian immunodeficiency virus (siv)mac 251 and sivsmmfgb, respectively, were evaluated. following siv infection, the macaques exhibited an apparent decline of cd4 + peripheral blood lymphocyte (pbl) counts, which was associated with a change in cdr3 ... | 1999 | 10593483 |
| use of herpesvirus saimiri-immortalized macaque cd4(+) t cell clones as stimulators and targets for assessment of ctl responses in macaque/aids models. | herpesvirus saimiri (hvs), a nonhuman primate gamma herpes virus, was used to immortalize pig-tailed macaque cd4(+) t lymphocytes. the hvs-immortalized t cell lines were used to develop cd4(+) t cell clones from two animals. three cd4(+) t cell clones were further characterized for the expression of cell surface markers. all expressed cd2, cd4, cd58, cd69 and cd80 and therefore resembled activated t cells. these clones required exogenous il-2 for efficient growth and were found to be highly susc ... | 1999 | 10594353 |
| cd4-independent, ccr5-dependent simian immunodeficiency virus infection and chemotaxis of human cells. | most simian immunodeficiency virus (siv), human immunodeficiency virus type 2 (hiv-2), and hiv-1 infection of host peripheral blood mononuclear cells (pbmcs) is cd4 dependent. in some cases, x4 hiv-1 chemotaxis is cd4 independent, and cross-species transmission might be facilitated by cd4-independent entry, which has been demonstrated for some siv strains in cd4(-) non-t cells. as expected for ccr5-dependent virus, siv required cd4 on rhesus and pigtail macaque pbmcs for infection and chemotaxis ... | 2000 | 10888609 |
| simian-human immunodeficiency virus-associated nephropathy in macaques. | a number of chimeric simian-human immunodeficiency virus (shiv) viruses containing tat, rev, vpu, and env from hiv-1 (strain hxbc2) in a genetic background of simian immunodeficiency virus (siv(mac)239) have been derived from the parental nonpathogenic shiv-4 virus. in this article we examine the renal pathology associated with the derivation of these pathogenic shiv strains. the first of the pathogenic shivs, shiv(ku-1), is associated with rapid cd4(+) t cell loss and opportunistic infections a ... | 2000 | 10957726 |
| mucosal challenge of macaca nemestrina with simian immunodeficiency virus (siv) following siv nucleocapsid mutant dna vaccination. | a simian immunodeficiency virus (siv)(mne) dna clone was constructed that produces viruses containing a four amino acid deletion in the second zinc finger of the nucleocapsid (nc) domain of the gag polyprotein. viruses produced from this clone, although non-infectious both in vitro and in vivo, complete a majority of the steps in a single retroviral infection cycle. eight pig-tailed macaques (macaca nemestrina) were inoculated intramuscularly and subcutaneously three times over the course of 24 ... | 2000 | 11085583 |
| protection of macaca nemestrina from disease following pathogenic simian immunodeficiency virus (siv) challenge: utilization of siv nucleocapsid mutant dna vaccines with and without an siv protein boost. | molecular clones were constructed that express nucleocapsid (nc) deletion mutant simian immunodeficiency viruses (sivs) that are replication defective but capable of completing virtually all of the steps of a single viral infection cycle. these steps include production of particles that are viral rna deficient yet contain a full complement of processed viral proteins. the mutant particles are ultrastructurally indistinguishable from wild-type virus. similar to a live attenuated vaccine, this app ... | 2000 | 11090194 |
| functional analyses of natural killer cells in macaques infected with neurovirulent simian immunodeficiency virus. | clearance of hiv and siv from the peripheral blood by the cellular immune system lessens the viral burden in infected individuals and may have an impact on virus infection of the cns and the development of cns lesions. however, the role of immune responses in preventing or limiting cns infection has not been clearly defined. we investigated the role of natural killer cells in the outcome of siv infection of macaques as a model for humans with aids and hiv encephalitis. in our study, six pig-tail ... | 2001 | 11519478 |
| determination of a statistically valid neutralization titer in plasma that confers protection against simian-human immunodeficiency virus challenge following passive transfer of high-titered neutralizing antibodies. | we previously reported that high-titered neutralizing antibodies directed against the human immunodeficiency virus type 1 (hiv-1) envelope can block the establishment of a simian immunodeficiency virus (siv)/hiv chimeric virus (shiv) infection in two monkeys following passive transfer (r. shibata et al., nat. med. 5:204-210, 1999). in the present study, increasing amounts of neutralizing immunoglobulin g (igg) were administered to 15 pig-tailed macaques in order to obtain a statistically valid p ... | 2002 | 11836389 |
| evolution of a human immunodeficiency virus type 1 variant with enhanced replication in pig-tailed macaque cells by dna shuffling. | dna shuffling facilitated the evolution of a human immunodeficiency virus type 1 (hiv-1) variant with enhanced replication in pig-tailed macaque peripheral blood mononuclear cells (pt mpbmc). this variant consists exclusively of hiv-1-derived sequences with the exception of simian immunodeficiency virus (siv) nef. sequences spanning the gag-protease-reverse transcriptase (gag-pro-rt) region from several hiv-1 isolates were shuffled and cloned into a parental hiv-1 backbone containing siv nef. ne ... | 2002 | 11861859 |
| the itam in nef influences acute pathogenesis of aids-inducing simian immunodeficiency viruses sivsm and sivagm without altering kinetics or extent of viremia. | the role of the immunoreceptor tyrosine-based activation motif (itam) that is unique to the nef protein of the acutely pathogenic simian immunodeficiency virus sivsmpbj was studied in the context of two aids-inducing simian immunodeficiency virus molecular clones. nefy(+) variants of sivagm9063-2 and sivsme543-3 replicated in and induced proliferation of unstimulated pig-tailed macaque pbmc. the pathogenesis of the nefy(+) and nefy(-) clones of sivagm9063-2, sivsme543-3, and pbj6.6 were evaluate ... | 2002 | 11932405 |
| innate differences between simian-human immunodeficiency virus (shiv)(ku-2)-infected rhesus and pig-tailed macaques in development of neurological disease. | neurological disease associated with hiv infection results from either primary replication of the virus or a combination of virus infection and replication of opportunistic pathogens in the cns. recent studies indicate that the primary infection is mediated mainly by viruses that utilize ccr5 as the coreceptor; it is not known whether the syndrome can be mediated by viruses that use the cxcr4 coreceptor. the macaque model of the disease using simian immunodeficiency virus (siv) has confirmed tha ... | 2002 | 12033765 |
| pathogenic and nef-interrupted simian-human immunodeficiency viruses traffic to the macaque cns and cause astrocytosis early after inoculation. | several studies have shown that deletion of the nef gene of simian immunodeficiency virus (siv) and simian-human immunodeficiency virus (shiv) results in attenuated viruses. however, studies have not critically examined trafficking of attenuated viruses to the central nervous system (cns) at early stages after inoculation. in this study, we investigated the colocalization of pathogenic and vpu-negative, nef-interrupted shivs at early stages following inoculation. the first virus, designated shiv ... | 2002 | 12036316 |
| engineered cd4- and cxcr4-using simian immunodeficiency virus from african green monkeys is neutralization sensitive and replicates in nonstimulated lymphocytes. | during human immunodeficiency virus type 1 (hiv-1) infection, disease progression correlates with the occurrence of variants using the coreceptor cxcr4 for cell entry. in contrast, apathogenic simian immunodeficiency virus (siv) from african green monkeys (sivagm), specifically the molecular virus clone sivagm3mc, uses ccr5, bob, and bonzo as coreceptors throughout the course of infection. the influence of an altered coreceptor usage on sivagm3mc replication was studied in vitro and in vivo. the ... | 2002 | 12368305 |
| capture and transfer of simian immunodeficiency virus by macaque dendritic cells is enhanced by dc-sign. | dendritic cells (dcs) are among the first cells encountered by human and simian immunodeficiency virus (hiv and siv) following mucosal infection. because these cells efficiently capture and transmit virus to t cells, they may play a major role in mediating hiv and siv infection. recently, a c-type lectin protein present on dcs, dc-specific icam-3-grabbing nonintegrin (dc-sign), was shown to efficiently bind and present hiv and siv to cd4(+), coreceptor-positive cells in trans. however, the signi ... | 2002 | 12414925 |
| role of microglial cells in selective replication of simian immunodeficiency virus genotypes in the brain. | an accelerated, consistent macaque simian immunodeficiency virus (siv) model in which over 90% of pigtailed macaques (macaca nemestrina) coinoculated with siv/17e-fr and siv/deltab670 developed encephalitis was used to determine whether central nervous system (cns) lesions are associated with the replication of specific genotypes in the brain and, more specifically, in the microglia. ten of 11 inoculated macaques had severe (n = 3), moderate (n = 5), or mild (n = 2) encephalitis at 3 months post ... | 2003 | 12477826 |
| resting cd4+ t lymphocytes but not thymocytes provide a latent viral reservoir in a simian immunodeficiency virus-macaca nemestrina model of human immunodeficiency virus type 1-infected patients on highly active antiretroviral therapy. | despite suppression of viremia in patients on highly active antiretroviral therapy (haart), human immunodeficiency virus type 1 persists in a latent reservoir in the resting memory cd4(+) t lymphocytes and possibly in other reservoirs. to better understand the mechanisms of viral persistence, we established a simian immunodeficiency virus (siv)-macaque model to mimic the clinical situation of patients on suppressive haart and developed assays to detect latently infected cells in the siv-macaque ... | 2003 | 12663799 |
| mechanistic understanding of an altered fidelity simian immunodeficiency virus reverse transcriptase mutation, v148i, identified in a pig-tailed macaque. | we have recently reported that the reverse transcriptase (rt) of sivmne 170 (170), which is a representative viral clone of the late symptomatic phase of infection with the parental strain, sivmne cl8 (cl8), has a largely increased fidelity, compared with the cl8 rt. in the present study, we analyzed the mechanistic alterations of the high fidelity 170 rt variant. first, we found that among several 170 rt mutations, only one, v148i, is solely responsible for the fidelity increase over the cl8 rt ... | 2003 | 12740369 |
| characterization of a simian human immunodeficiency virus encoding the envelope gene from the ccr5-tropic hiv-1 ba-l. | the tat, rev, vpu, and env genes from the monocytotropic ccr5-dependent hiv-1 ba-l isolate were substituted for homologous simian immunodeficiency virus (siv) sequences in the siv genome. the resultant shiv (shiv ba-l) replicated in ccr5-positive pm-1 cells but not in ccr5-negative cemx174 cells. infection of hos cells expressing different co-receptors showed shiv ba-l to be strictly ccr5-dependent. infection of pm-1 cells and rhesus peripheral blood mononuclear cells (pbmcs) was highly sensitiv ... | 2003 | 12843740 |
| central nervous system correlates of behavioral deficits following simian immunodeficiency virus infection. | despite the high incidence of cognitive and motor impairment in acquired immunodeficiency syndrome (aids) patients, the mechanisms of aids-related central nervous system (cns) pathology are not completely understood. infection with simian immunodeficiency virus (siv) in macaques provides an excellent model of aids, including human immunodeficiency virus (hiv)-induced cns pathology and cognitive/behavioral impairment. co-inoculation with two siv strains, siv/17e-fr and siv/deltab670, accelerates ... | 2003 | 12907390 |
| immunoglobulin-a nephropathy with crescentic glomerulonephritis in a pigtailed macaque (macaca nemestrina). | a 4-year-old female pigtailed macaque (macaca nemestrina), experimentally coinfected with simian immunodeficiency virus (sivmac251) and mycobacterium bovis(bacillus calmette-guerin), was euthanatized 1 year after infection because of weight loss and labored breathing. on gross examination, both kidneys were found to be markedly enlarged (right: 54.7 g and left: 51.7 g; normal < 20 g). renal lesions were evaluated by histopathologic, immunohistochemical, and ultrastructural methods. light microsc ... | 2004 | 14715967 |
| correlation of acute humoral response with brain virus burden and survival time in pig-tailed macaques infected with the neurovirulent simian immunodeficiency virus sivsmmfgb. | infection of pig-tailed macaques with the simian immunodeficiency virus (siv) isolate sivsmmfgb frequently results in siv encephalitis (sive) in addition to immunodeficiency and acquired immune deficiency syndrome. we used in situ hybridization to quantitate the number of siv-infected cells in brain parenchyma, choroid plexus, and meninges from 17 macaques that developed acquired immune deficiency syndrome after infection with sivsmmfgb. siv-infected cells and histopathological lesions of sive w ... | 2004 | 15039205 |
| a single amino acid change in gp41 is linked to the macrophage-only replication phenotype of a molecular clone of simian immunodeficiency virus derived from the brain of a macaque with neuropathogenic infection. | simian immunodeficiency virus (siv)-related neuropathogenesis has been observed in 90% of pig-tailed macaques infected with strain sivsmmfgb, making it an excellent system for studying human immunodeficiency virus (hiv)-associated neurological disease. to investigate the genetics of siv neurovirulence, infectious molecular clones were generated from the brain of a sivsmmfgb-infected pig-tailed macaque. one clone, bpzm.12, displayed a macrophage-restricted phenotype not previously described; this ... | 2004 | 15246269 |
| a real-time pcr-based method to independently sample single simian immunodeficiency virus genomes from macaques with a range of viral loads. | the generation of a diverse population of viral variants is a hallmark of simian immunodeficiency virus (siv) infection. in order to address what role this diversity plays in disease progression, accurate sampling of the viral population is necessary. however, traditional pcr-based methods often rely on amplification of multiple genomes in one reaction, leading to resampling of viral genomes and potential errors in the estimations of viral diversity, especially when sequences from only one or a ... | 2004 | 15525323 |
| in vitro characterization of a simian immunodeficiency virus-human immunodeficiency virus (hiv) chimera expressing hiv type 1 reverse transcriptase to study antiviral resistance in pigtail macaques. | antiviral resistance is a significant obstacle in the treatment of human immunodeficiency virus type 1 (hiv-1)-infected individuals. because nonnucleoside reverse transcriptase inhibitors (nnrtis) specifically target hiv-1 reverse transcriptase (rt) and do not effectively inhibit simian immunodeficiency virus (siv) rt, the development of animal models to study the evolution of antiviral resistance has been problematic. to facilitate in vivo studies of nnrti resistance, we examined whether a siv ... | 2004 | 15564466 |
| analysis of pigtail macaque major histocompatibility complex class i molecules presenting immunodominant simian immunodeficiency virus epitopes. | successful human immunodeficiency virus (hiv) vaccines will need to induce effective t-cell immunity. we studied immunodominant simian immunodeficiency virus (siv) gag-specific t-cell responses and their restricting major histocompatibility complex (mhc) class i alleles in pigtail macaques (macaca nemestrina), an increasingly common primate model for the study of hiv infection of humans. cd8+ t-cell responses to an siv epitope, gag164-172kp9, were present in at least 15 of 36 outbred pigtail mac ... | 2005 | 15613296 |
| plateau levels of viremia correlate with the degree of cd4+-t-cell loss in simian immunodeficiency virus sivagm-infected pigtailed macaques: variable pathogenicity of natural sivagm isolates. | simian immunodeficiency virus from african green monkeys (sivagm) results in asymptomatic infection in its natural host species. the virus is not inherently apathogenic, since infection of pigtailed (pt) macaques (macaca nemestrina) with one isolate of sivagm results in an immunodeficiency syndrome characterized by progressive cd4+-t-cell depletion and opportunistic infections. this virus was passaged once in a pt macaque and, thus, may not be entirely reflective of the virulence of the parental ... | 2005 | 15795299 |
| rapid viral escape at an immunodominant simian-human immunodeficiency virus cytotoxic t-lymphocyte epitope exacts a dramatic fitness cost. | escape from specific t-cell responses contributes to the progression of human immunodeficiency virus type 1 (hiv-1) infection. t-cell escape viral variants are retained following hiv-1 transmission between major histocompatibility complex (mhc)-matched individuals. however, reversion to wild type can occur following transmission to mhc-mismatched hosts in the absence of cytotoxic t-lymphocyte (ctl) pressure, due to the reduced fitness of the escape mutant virus. we estimated both the strength of ... | 2005 | 15827187 |
| mucosally-administered human-simian immunodeficiency virus dna and fowlpoxvirus-based recombinant vaccines reduce acute phase viral replication in macaques following vaginal challenge with ccr5-tropic shivsf162p3. | further advances are required in understanding protection from aids by t cell immunity across mucosal sites of virus transmission. we analysed a set of multigenic hiv and shiv dna and fowlpoxvirus (fpv) prime and boost vaccines for immunogenicity and protective efficacy in outbred pigtail macaques when delivered via mucosal surfaces (intranasally or intrarectally). intranasally delivered dna, even when adjuvanted and given as a fine droplet spray, was neither immunogenic nor protective in macaqu ... | 2005 | 15985317 |
| the pigtail macaque mhc class i allele mane-a*10 presents an immundominant siv gag epitope: identification, tetramer development and implications of immune escape and reversion. | the pigtail macaque (macaca nemestrina) is a common model for the study of aids. the pigtail major histocompatibility complex class i allele mane-a*10 restricts an immunodominant simian immunodeficiency virus (siv) gag epitope (kp9) which rapidly mutates to escape t cell recognition following acute simian/human immunodeficiency virus infection. two technologies for the detection of mane-a*10 in outbred pigtail macaques were developed: reference strand-mediated conformational analysis and sequenc ... | 2005 | 16128923 |
| immunodeficiency in the absence of high viral load in pig-tailed macaques infected with simian immunodeficiency virus sivsun or sivlhoest. | simian immunodeficiency virus (siv) is known to result in an asymptomatic infection of its natural african monkey host. however, some siv strains are capable of inducing aids-like symptoms and death upon experimental infection of asian macaques. to further investigate the virulence of natural siv isolates from african monkeys, pig-tailed (pt) macaques were inoculated intravenously with either of two recently discovered novel lentiviruses, sivlhoest and sivsun. both viruses were apparently apatho ... | 2005 | 16254339 |
| characterization of an anti-lymphocyte function-associated antigen-1 antibody in a simian immunodeficiency virus-pig-tailed macaque (macaca nemestrina) model. | the simian immunodeficiency virus (siv)/pig-tailed macaque (macaca nemestrina) model of acquired immune deficiency syndrome (aids) is a powerful system in which to study cell adhesion molecules and retroviral pathogenesis in vivo. preliminary experiments were conducted to examine the role of lymphocyte function-associated antigen 1 (lfa-1) in early siv infection in vivo by using an lfa-1 monoclonal antibody (mhm.23) specific to human lfa-1. in vitro studies revealed that at concentrations of > o ... | 2006 | 16521856 |
| generation of hiv-1 derivatives that productively infect macaque monkey lymphoid cells. | the narrow host range of human immunodeficiency virus type 1 (hiv-1) is caused in part by innate cellular factors such as apolipoprotein b mrna-editing enzyme-catalytic polypeptide-like 3g (apobec3g) and trim5alpha, which restrict virus replication in monkey cells. variant hiv-1 molecular clones containing both a 21-nucleotide simian immunodeficiency virus (siv) gag ca element, corresponding to the hiv-1 cyclophilin a-binding site, and the entire siv vif gene were constructed. long-term passage ... | 2006 | 17065315 |
| early dysregulation of cripto-1 and immunomodulatory genes in the cerebral cortex in a macaque model of neuroaids. | human immunodeficiency virus type 1 (hiv-1) and related primate lentiviruses are known to enter the central nervous system (cns) during the primary phase of infection. neuroinvasion by simian immunodeficiency virus and simian human immunodeficiency virus (shiv) is characterized by transient meningitis and astrocytosis. in this report, we used targeted cytokine cdna arrays to analyze cortical brain tissue from four pig-tailed macaques inoculated for 2 weeks with pathogenic shiv(50olnv) and a norm ... | 2006 | 17084529 |
| mhc class i allele frequencies in pigtail macaques of diverse origin. | pigtail macaques (macaca nemestrina) are an increasingly common primate model for the study of human aids. major histocompatibility complex (mhc) class i-restricted cd8(+) t cell responses are a critical part of the adaptive immune response to hiv-1 in humans and simian immunodeficiency virus (siv) in macaques; however, mhc class i alleles have not yet been comprehensively characterized in pigtail macaques. the frequencies of ten previously defined alleles (four mane-a and six mane-b) were inves ... | 2006 | 17096100 |
| in vivo fitness costs of different gag cd8 t-cell escape mutant simian-human immunodeficiency viruses for macaques. | the kinetics of immune escape and reversion depend upon the efficiency of cd8 cytotoxic t lymphocytes (ctl) and the fitness cost of escape mutations. escape kinetics of three simian immunodeficiency virus gag ctl epitopes in pigtail macaques were variable; those of kp9 and af9 were faster than those of kw9. kinetics of reversion of escape mutant virus to wild type upon passage to naïve major histocompatibility complex-mismatched macaques also varied. rapid reversion occurred at kp9, gradual biph ... | 2007 | 17344299 |
| human herpesvirus 6a accelerates aids progression in macaques. | although hiv is the necessary and sufficient causative agent of aids, genetic and environmental factors markedly influence the pace of disease progression. clinical and experimental evidence suggests that human herpesvirus 6a (hhv-6a), a cytopathic t-lymphotropic dna virus, fosters the progression to aids in synergy with hiv-1. in this study, we investigated the effect of coinfection with hhv-6a on the progression of simian immunodeficiency virus (siv) disease in pig-tailed macaques (macaca neme ... | 2007 | 17360322 |
| functional genomics analyses of differential macaque peripheral blood mononuclear cell infections by human immunodeficiency virus-1 and simian immunodeficiency virus. | the pathogenicity of the primate lentiviruses, human, and simian immunodeficiency viruses, is host-specific. previous studies indicated that the highly pathogenic human lentivirus hiv-1 has markedly reduced pathogenicity compared to the pathogenic simian lentivirus siv in pigtail macaques (macaca nemestrina). we therefore hypothesized that the pigtail macaque peripheral blood mononuclear cells (mpbmcs) would respond differently to infections of hiv-1 and pathogenic siv. to elucidate the cellular ... | 2007 | 17507074 |
| human immunodeficiency virus type 1 derivative with 7% simian immunodeficiency virus genetic content is able to establish infections in pig-tailed macaques. | a human immunodeficiency virus type 1 (hiv-1) derivative (hiv(nl-dt5r)) containing sequences encoding a 7-amino-acid segment of ca and the entire vif gene from simian immunodeficiency virus (siv) was previously shown to establish spreading infections in cultured macaque peripheral blood mononuclear cells. to assess its replicative and disease-inducing properties in vivo, hiv(nl-dt5r) was inoculated into pig-tailed macaques. hiv(nl-dt5r) generated plasma viremia in all five of the monkeys and eli ... | 2007 | 17670817 |
| novel trim5 isoforms expressed by macaca nemestrina. | the trim5 family of proteins contains a ring domain, one or two b boxes, and a coiled-coil domain. the trim5alpha isoform also encodes a c-terminal b30.2(spry) domain, differences within which define the breadth and potency of trim5alpha-mediated retroviral restriction. because macaca nemestrina animals are susceptible to some human immunodeficiency virus (hiv) isolates, we sought to determine if differences exist in the trim5 gene and transcripts of these animals. we identified a two-nucleotide ... | 2007 | 17804491 |
| suppression of viremia and evolution of human immunodeficiency virus type 1 drug resistance in a macaque model for antiretroviral therapy. | antiretroviral therapy (art) in human immunodeficiency virus type 1 (hiv-1)-infected patients does not clear the infection and can select for drug resistance over time. not only is drug-resistant hiv-1 a concern for infected individuals on continual therapy, but it is an emerging problem in resource-limited settings where, in efforts to stem mother-to-child-transmission of hiv-1, transient nonnucleoside reverse transcriptase inhibitor (nnrti) therapy given during labor can select for nnrti resis ... | 2007 | 17855539 |
| killing kinetics of simian immunodeficiency virus-specific cd8+ t cells: implications for hiv vaccine strategies. | both the magnitude and function of vaccine-induced hiv-specific cd8+ ctls are likely to be important in the outcome of infection. we hypothesized that rapid cytolysis by ctls may facilitate control of viral challenge. release kinetics of the cytolytic effector molecules granzyme b and perforin, as well as the expression of the degranulation marker cd107a and ifn-gamma were simultaneously studied in siv gag(164-172) kp9-specific cd8+ t cells from mane-a*10+ pigtail macaques. macaques were vaccina ... | 2007 | 17878354 |