| cloning and sequences of primate cd4 molecules: diversity of the cellular receptor for simian immunodeficiency virus/human immunodeficiency virus. | to study the interaction between the primate lentiviruses simian immunodeficiency virus (siv) and human immunodeficiency virus (hiv) and the cd4 receptor we have cloned and sequenced the cd4 molecule from six non-human primate species: african green monkeys (three subspecies: sabeus, pytherethrus, aethiops), sooty mangabeys, patas monkeys, chimpanzees, rhesus macaques, and pig-tail macaques. molecular cdna clones representing cd4 mrna were generated from total rna from peripheral blood mononucle ... | 1992 | 1425921 |
| 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 |
| prevention of hiv-2 and sivsm infection by passive immunization in cynomolgus monkeys. | infection of macaques with simian immunodeficiency virus (siv) and human immunodeficiency virus type 2 (hiv-2) are useful models for studies of immunotherapy and vaccination against hiv as well as for testing of antiviral drugs. vaccine research showing protective immunity in immunized monkeys has indicated that it will be possible to develop a vaccine for prevention of human hiv infection, although many hurdles remain. the design of an hiv vaccine would be helped if the basis of the protective ... | 1991 | 1677743 |
| 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 |
| glycosylation of the envelope glycoprotein gp130 of simian immunodeficiency virus from sooty mangabey (cercocebus atys). | the envelope glycoprotein 130 ('130' referring to an mr of 130,000) of simian immunodeficiency virus from sooty mangabey (cercocebus atys) (sivsm) was isolated from the cell-free supernatant of the sivsm-infected human t-cell line h9, metabolically labelled with d-[6-3h]glucosamine. after digestion with staphylococcus aureus v8 proteinase, radiolabelled n-glycans were liberated from resulting glycopeptides by sequential treatment with endo-beta-n-acetylglucosaminidase h and peptide:n-glycosidase ... | 1990 | 2339985 |
| a highly divergent hiv-2-related isolate. | it has been suggested that the human immunodeficiency virus type 2 (hiv-2) and the simian immunodeficiency virus from rhesus macaques (sivmac) evolved from the sooty mangabey virus sivsm (ref. 1). we now describe an hiv-2-related isolate, hiv-2-d205, from a healthy ghanaian woman that is genetically equidistant to the prototypic hiv-2 strains and to sivsm and sivmac. supported by the observation that hiv-2d205 differs in a step of envelope glycoprotein processing, our data indicate that it could ... | 1989 | 2594088 |
| 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 |
| sequence of a novel simian immunodeficiency virus from a wild-caught african mandrill. | since the isolation of an hiv-2-related virus from captive macaques (sivmac), the origin of human immunodeficiency viruses, a much debated subject, has been attributed to monkeys. the sequence of sivagm, which is derived from a naturally infected african green monkey, shows equal relatedness to hiv-1 and hiv-2, suggesting that the derivation of these viruses from sivagm is unlikely. recent sequence analysis of siv from a captive sooty mangabey (sivmac), however, shows its close relatedness to hi ... | 1989 | 2797181 |
| 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 |
| 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 |
| a distinct african lentivirus from sykes' monkeys. | asymptomatic infection with simian immunodeficiency virus (siv) has been demonstrated in african sykes' monkeys (cercopithecus mitis albogularis), and virus isolation confirmed infection with a novel siv from sykes' monkeys (sivsyk). macaques inoculated with sivsyk became persistently infected but remained clinically healthy. we utilized polymerase chain reaction amplification to generate a full-length, infectious molecular clone of sivsyk. the genome organization of sivsyk is similar to that of ... | 1993 | 8382307 |
| a simple method to distinguish between simian immunodeficiency virus isolates by restriction analysis of pcr products. | a simple method to distinguish between simian immunodeficiency virus (siv) isolates of experimentally infected rhesus macaques is reported. peripheral blood mononuclear cells (pbmc) were prepared from a rhesus macaque infected with sivstm isolated originally from a stump-tailed macaque, or from a rhesus monkey infected with sivsm from a sooty mangabey monkey. pbmc were cocultivated with cem x 174 cells and a region of the siv envelope (env) gene was amplified by the polymerase chain reaction (pc ... | 1993 | 8397819 |
| isolation and characterization of simian immunodeficiency virus from african white-crowned mangabey monkeys (cercocebus torquatus lunulatus). | forty-eight of 236 sera from seven species of african non-human primates in kenya, including those of white-crowned mangabey monkeys (cercocebus torquatus lunulatus) had antibodies to simian immunodeficiency viruses (sivs). isolates of simian lentivirus were obtained from seropositive white-crowned mangabey monkeys which are indigenous in west africa. this virus, designated as sivwcm, appeared morphologically similar to hiv by electron microscopy, showed mg(2+)-dependent reverse transcriptase ac ... | 1993 | 8470959 |
| rates of amino acid change in the envelope protein correlate with pathogenicity of primate lentiviruses. | a spectrum of pathogenicity has been observed for primate lentiviruses in their natural hosts. for example, human immunodeficiency virus type 1 (hiv-1) is a potent etiologic agent for aids in man, whereas there is no evidence to date which indicates that simian immunodeficiency virus from african green monkeys (sivagm) causes immunodeficiency in agm. we measured the relative rates of amino acid change, as the ratio of the number of nonsynonymous to synonymous (silent) nucleotide substitutions, f ... | 1993 | 8395604 |
| 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 |
| inhibition of cellular activation of retroviral replication by cd8+ t cells derived from non-human primates. | to test the hypothesis that cd8+ t cells inhibit viral replication at the level of cellular activation, an epstein-barr virus (ebv)-transformed cell line (fec1) from a simian immunodeficiency virus (siv)-seropositive sooty mangabey monkey was transfected with a human cd4 gene and shown to be replication-competent for hiv-1, hiv-2 and siv. utilizing a dual-chamber culture system, it was found that inhibition of viral replication can be mediated by a soluble factor. the fec1 cell line was transien ... | 1993 | 8383022 |
| evidence for simian immunodeficiency virus-specific igm and igg response in peripheral blood mononuclear cells of serum enzyme-linked immunosorbent assay-negative nonhuman primates. | in vitro polyclonal activation of peripheral blood mononuclear cells (pbmcs) from 70% of the simian immunodeficiency virus (siv) serum enzyme-linked, immunosorbent assay (elisa)-negative sooty mangabeys leads to synthesis and release of low but significant and reproducible levels of siv-reactive antibodies, as determined by elisa and western blot analysis. the predominant isotype of siv-reactive antibodies in the pokeweed mitogen (pwm) supernatant fluids from serum elisa-negative mangabeys is ig ... | 1994 | 8176639 |
| broad cross-neutralizing activity in serum is associated with slow progression and low risk of transmission in primate lentivirus infections. | sera from human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2)-infected humans were tested with autologous (from the same individual) and heterologous (from other individuals) virus isolates in a neutralization assay. similarly, sera from experimentally simian immunodeficiency virus (sivsm from sooty mangabey) or hiv-2sbl6669-infected cynomolgus macaques were tested for neutralizing activity against autologous and heterologous reisolates. in the neutralization assay, the virus dose r ... | 1996 | 8811351 |
| biphasic in vitro regulation of retroviral replication by cd8+ cells from nonhuman primates. | cd8+ t cells from naturally infected disease-resistant sooty mangabeys (cercocebus atys) secrete a soluble factor which inhibits the in vitro replication of the simian immunodeficiency virus (siv). to gain further insight on the mechanism(s) involved, cd8+ effector t cells and target cells from sooty mangabeys were immortalized and cloned. the target cells were then stably transfected with an siv-ltr-cat construct or with the parental cat plasmid as a control. a quantitative rt-pcr method, provi ... | 1994 | 8158536 |
| mosaic genome structure of simian immunodeficiency virus from west african green monkeys. | elucidation of the phylogenetic origins of simian and human immunodeficiency viruses (siv and hiv) is fundamental to the understanding of hiv pathogenesis and the spread of aids worldwide. in this study, we molecularly characterized multiple sivagm isolates from four different african green monkey species (vervet, grivet, sabaeus and tantalus monkeys). phylogenetic analysis of partial (1 kb) env sequences indicated that all sivagm strains cluster together, and that they fall into four distinct s ... | 1994 | 8026477 |
| international collaboration comparing neutralization and binding assays for monoclonal antibodies to simian immunodeficiency virus. | thirteen laboratories characterized a coded panel of 10 mabs to sivmac251 envelope protein in a collaboration organized by the national institute of allergy and infectious diseases (niaid). the mabs were examined against siv isolates in neutralization and radioimmune precipitation, immunoblot, enzyme-linked immunosorbent, and radioimmune assays. although laboratories employed diverse neutralization assays that varied in sensitivity there was agreement on the relative ability of the mabs to neutr ... | 1993 | 7686385 |
| sequence of simian immunodeficiency virus from macaque and its relationship to other human and simian retroviruses. | because of the growing incidence of aids (acquired immune deficiency syndrome), the need for studies on animal models is urgent. infection of chimpanzees with the retroviral agent of human aids, the human immunodeficiency virus (hiv), will have only limited usefulness because chimpanzees are in short supply and do not develop the disease. among non-human primates, both type d retroviruses and lentiviruses can be responsible for immune deficiencies. the d-type retroviruses, although important pat ... | 1987 | 3649576 |
| 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 |
| relation between phylogeny of african green monkey cd4 genes and their respective simian immunodeficiency virus genes. | an apparent species-specific relatedness of sivagm suggests a coevolution with their natural hosts. however, the exact species or subspecies classification of african green monkeys, agm, is uncertain because current classification schemes rely on phenotype markers, while more definitive genetic data are lacking. in this study, the cd4 protein involved in tissue type recognition was genetically cloned and sequenced from pbmc rna from all agm species, including barbados green monkeys (bgm). phylog ... | 1997 | 9379478 |
| cloning of htlv-4 and its relation to simian and human immunodeficiency viruses. | although much is now known of the strain variation among the type-1 human immunodeficiency virus (hiv-1), which is the cause of aids (acquired immune deficiency syndrome) in the united states, europe, and central africa, much less is yet known about a second group of viruses that have been found in west africans. one member of this group, named human t-cell lymphotropic virus type 4 (htlv-4), has been isolated from healthy senegalese. another is the virus isolated from west africans with aids-li ... | 1987 | 3104797 |
| structured-tree topology and adaptive evolution of the simian immunodeficiency virus sivsm envelope during serial passage in rhesus macaques according to likelihood mapping and quartet puzzling. | species-specific strains of simian immunodeficiency virus (siv) are nonpathogenic in african primates. the siv strain most closely related to human immunodeficiency virus type 2 (hiv-2) is sivsm, the strain specific to the sooty mangabey (cercocebus atys). infection of asian primates with siv causes aids and allows the study of the adaptive evolution of a lentivirus to replicate efficiently in a new host, providing a useful animal model of hiv infection and aids in humans. serial passage of sivs ... | 1998 | 9557648 |
| genetic diversity of simian immunodeficiency virus. | we have demonstrated that the genetic diversity of simian immunodeficiency virus from african green monkeys (sivagm) is much greater than that observed previously for individual hiv-1, hiv-2, or sivmac isolates. extensive genetic variation among sivagm isolates and the high prevalence of green monkey infection without disease suggest that the virus has been in the green monkey population for a long time. we have also demonstrated that siv from a sooty mangabey monkey (isolate smm-7) is closer to ... | 1989 | 2569537 |
| interactions between simian immunodeficiency virus and mycobacterium leprae in experimentally inoculated rhesus monkeys. | thirty-four rhesus monkeys were inoculated with mycobacterium leprae inoculum isolated from sooty mangabey monkeys with leprosy. later it was learned that one of the m. leprae-donor mangabeys was asymptomatically infected with simian immunodeficiency virus (siv). thus, five of the rhesus monkey were coinoculated with m. leprae and siv. three of the five became siv-positive and developed signs of leprosy and an aids-like illness. two animals remained healthy. the coinoculated leprosy-positive rhe ... | 1989 | 2547881 |
| antibody-dependent enhancement of siv infection: further characterization and cross reactivity between macaque and sooty mangabey isolates. | plasma from four rhesus macaques (macaca mulatta), of which two were experimentally infected with the simian immunodeficiency virus (siv) isolate sivmac251, one with isolate sivsmf236, and another with a sivsmf236 molecular clone, sivsmh-4, enhanced sivmac infection of mt-2 cells. in addition to siv-positive plasma, infection-enhancement required complement, cd4, and cr2. titers of infection-enhancing antibodies appeared to correlate with disease progression. the mt-2/sivmac251 system should be ... | 1990 | 2231684 |
| prevalence of natural infection with simian immunodeficiency virus and simian t-cell leukemia virus type i in a breeding colony of sooty mangabey monkeys. | the seroprevalence of antibodies to simian immunodeficiency virus (sivsmm) and simian t-cell leukemia virus type i (stlv-i) in a captive breeding colony of sooty mangabey monkeys was determined, and infection by sivsmm was confirmed in all cases by virus isolation. among 138 animals tested, 57 and 33% were infected with sivsmm and stlv-i, respectively. while the proportion of female mangabeys (66%) differed significantly (p less than 0.01) from the proportion of male mangabeys (42%) infected wit ... | 1990 | 2168716 |
| 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 |
| pathology of dual mycobacterium leprae and simian immunodeficiency virus infection in rhesus monkeys. | three rhesus monkeys were experimentally inoculated with sooty-mangabey-derived mycobacterium leprae and were inadvertently infected with the simian immunodeficiency virus (siv) as well. they died of an immunodeficiency syndrome, and at autopsy all had lesions caused by m. leprae. one monkey was inoculated twice with m. leprae, initially with an inoculum from a sooty mangabey that was not infected with siv and, subsequently, with an inoculum from a mangabey that was siv infected. the monkey did ... | 1990 | 2165511 |
| requirements for simian immunodeficiency virus antigen-specific in vitro proliferation of t cells from infected rhesus macaques and sooty mangabeys. | the measurement of cell-mediated immunity against the etiologic agent of human aids (hiv) in the non-human primate model of aids (simian immunodeficiency virus, siv) has been difficult. in general, culture of peripheral blood mononuclear cells from hiv-1- and siv-infected humans and monkeys, respectively, with purified inactivated hiv and siv virus preparations has given inconsistent or negative proliferative responses. however, we describe herein an assay which consists of coculturing monocytes ... | 1990 | 2164818 |
| natural infection of a homozygous delta24 ccr5 red-capped mangabey with an r2b-tropic simian immunodeficiency virus. | a homozygous 24-bp deletion (delta24) was found in the cc chemokine receptor 5 (ccr5) of 11 out of 15 red-capped mangabeys (rcms), cercocebus torquatus torquatus, both in africa and in an american zoo. the ccr5 delta24 defect encompassed eight amino acids in frame in the fourth transmembrane region. unexpectedly, rcm-009, one of 11 homozygotes (delta24ccr5/ delta24ccr5), was found to be naturally infected with a divergent simian immunodeficiency virus (siv) strain, which was not r5-tropic, but u ... | 1998 | 9841919 |
| transmission of retroviral infection by transfusion of seronegative blood in nonhuman primates. | techniques such as polyclonal b cell activation with pokeweed mitogen (pwm) and polymerase chain reaction (pcr) analysis have documented the existence of simian immunodeficiency virus (siv)-and human immunodeficiency virus type 1-seronegative but infected humans and nonhuman primates. to establish whether blood from such seronegative but pwm- and pcr-positive monkeys can transmit infection, naive macaques were transfused with whole blood (n = 2) or cultured cells and supernatant fluid (n = 2) fr ... | 1991 | 2037788 |
| detection of occult simian immunodeficiency virus sivsmm infection in asymptomatic seronegative nonhuman primates and evidence for variation in siv gag sequence between in vivo- and in vitro-propagated virus. | polymerase chain reaction techniques were used to identify simian immunodeficiency virus (siv) sivsmm gag sequences in genomic dna isolated from peripheral blood mononuclear cells from naturally infected asymptomatic seropositive and seronegative sooty mangabeys (cercocebus atys) and from experimentally infected but asymptomatic rhesus macaques (macaca mulatta). the results indicate that most if not all siv-seronegative mangabeys from the colony at the yerkes primate center are in fact infected ... | 1991 | 2002546 |
| sivsmm infection of macaque and mangabey monkeys: correlation between in vivo and in vitro properties of different isolates. | simian immunodeficiency virus from sooty mangabey monkeys (sivsmm), a lentivirus closely related to siv from macaques and the human immunodeficiency virus type 2 (hiv-2), is pathogenic for various species of macaques but is nonpathogenic for mangabeys. comparison of in vivo and in vitro responses of macaques and mangabeys or their lymphocytes, respectively, to sivsmm infection indicated that lack of disease in mangabeys apparently was not due to effective control of virus expression by the immun ... | 1990 | 1980901 |
| a highly divergent simian immunodeficiency virus (sivstm) recovered from stored stump-tailed macaque tissues. | we report here the results of molecular analysis of a simian immunodeficiency virus (designated sivstm) which was isolated from a rhesus monkey inoculated with stored lymph node tissue of an asian stump-tailed macaque. the latter monkey had died in 1977 during an epidemic of acquired immunodeficiency and lymphoma at the california regional primate research center (l. j. lowenstine, n. w. lerche, p. a. marx, m. b. gardner, and n. c. pedersen, p. 174-176, in m. girard and l. valette, ed., retrovir ... | 1991 | 1942258 |
| simian immunodeficiency virus utilizes human and sooty mangabey but not rhesus macaque strl33 for efficient entry. | it has been established that many simian immunodeficiency virus (siv) isolates utilize the orphan receptors gpr15 and strl33 about as efficiently as the chemokine receptor ccr5 for entry into target cells. most studies were performed, however, with coreceptors of human origin. we found that siv from captive rhesus macaques (sivmac) can utilize both human and simian ccr5 and gpr15 with comparable efficiencies. strikingly, however, only human strl33 (hustrl33), not rhesus macaque strl33 (rhstrl33) ... | 2000 | 10799581 |
| simian immunodeficiency viruses of diverse origin can use cxcr4 as a coreceptor for entry into human cells. | primary simian immunodeficiency virus (siv) isolated from sooty mangabey (sivsm [n = 6]), stumptail (sivstm [n = 1]), mandrill (sivmnd [n = 1]), and african green (sivagm [n = 1]) primates were examined for their ability to infect human cells and for their coreceptor requirements. all isolates infected human peripheral blood mononuclear cells (pbmcs) from a ccr5(+/+) donor, and seven of eight isolates tested also infected ccr5(-/-) pbmcs. analysis of coreceptor utilization using ghost and u87 ce ... | 2000 | 10823878 |
| isolation of a simian immunodeficiency virus related to human immunodeficiency virus type 2 from a west african pet sooty mangabey. | two of 25 healthy pet sooty mangabey (sm) monkeys (cercocebus atys) living in west africa were seropositive by immunoblot when surveyed for antibody to simian immunodeficiency virus of macaques (sivmac). sivsmlib1 was isolated from one of the pet sooty mangabeys. nucleotide sequence data showed that this isolate is a member of the sivsm/human immunodeficiecy virus type 2 (hiv-2)/sivmac group of primate lentiviruses. furthermore, sequence comparisons revealed extensive genetic diversity among siv ... | 1991 | 1840620 |
| humoral response to siv/smm infection in macaque and mangabey monkeys. | natural infection of sooty mangabey monkeys with simian immunodeficiency virus, designated siv/smm, results in long-term persistent infections with little or no disease. in contrast, experimental infection of macaques with isolates of siv/smm induces chronic and progressive disease that terminates in an aids-like illness and death in most animals. to determine whether antibodies might be important in preventing the development of disease in mangabeys or progression of disease in macaques, humora ... | 1990 | 1690284 |
| characterization of monoclonal antibodies that distinguish simian immunodeficiency virus isolates from each other and from human immunodeficiency virus types 1 and 2. | two monoclonal antibodies (mabs) against p27 and one against p17 of simian immunodeficiency virus (siv) from rhesus macaques were produced and characterized by reacting with disrupted, viral antigens on immunoblots. human immunodeficiency virus type 1 (hiv-1), hiv-2 and siv isolates from sooty mangabey, stump-tailed macaque, rhesus macaque and african green monkey (sivsm, sivstm, sivmac and sivagm) were used for comparative analysis. the p27 monoclonal antibodies he3 and fa2 reacted with sivmac ... | 1990 | 1689369 |
| relationship of neurologic status in macaques infected with the simian immunodeficiency virus to cerebrospinal fluid quinolinic acid and kynurenic acid. | increased concentrations of the excitotoxin quinolinic acid (quin) have been implicated in the neurologic deficits and brain atrophy that may accompany infection with the human immunodeficiency virus type-1. key neuropathologic features of the aids encephalitis are replicated in some macaques following infection with the simian immunodeficiency virus (siv). in the present studies, cerebrospinal fluid (csf) quin concentrations increased within 2 weeks following infection of 11 rhesus macaques (ma ... | 1992 | 1535532 |
| shared antigenic epitopes of the major core proteins of human and simian immunodeficiency virus isolates. | antigenic epitopes on the major core (gag) protein of isolates of simian and human immunodeficiency virus (siv and hiv) were compared using a panel of eleven mouse monoclonal antibodies (mabs) that recognized nine distinct gag epitopes. viral isolates used for comparison were hiv-1iiib, hiv-2rod, and siv isolates from macaque (sivmac), sooty mangabey (sivsm-ucd), african green monkey (sivagm), and stump-tailed macaque (sivstm-ucd). the relatedness of the various hiv and siv isolates, as determin ... | 1992 | 1383547 |
| wild mandrillus sphinx are carriers of two types of lentivirus. | mandrillus sphinx, a large primate living in cameroon and gabon and belonging to the papionini tribe, was reported to be infected by a simian immunodeficiency virus (siv) (sivmndgb1) as early as 1988. here, we have identified a second, highly divergent sivmnd (designated sivmnd-2). genomic organization differs between the two viral types; sivmnd-2 has the additional vpx gene, like other sivs naturally infecting the papionini tribe (sivsm and sivrcm) and in contrast to the other sivmnd type (here ... | 2001 | 11435589 |
| a divergent simian immunodeficiency virus from sooty mangabey with an atypical tat-tar structure. | sivsm, the simian immunodeficiency virus that naturally infects sooty mangabeys in west africa, is the closest lentiviral relative of human immunodeficiency virus type 2 (hiv-2). to determine the genetic characteristics of sivsm in its natural host, we sequenced the full-length genome of sivsmsl92b, a primary isolate obtained from a pet sooty mangabey in sierra leone. sivsmsl92b proved to be the most divergent member of the hiv-2/sivsm lineage found thus far, having as much as 35% nucleotide div ... | 2001 | 11522185 |
| genetic characterization of new west african simian immunodeficiency virus sivsm: geographic clustering of household-derived siv strains with human immunodeficiency virus type 2 subtypes and genetically diverse viruses from a single feral sooty mangabey troop. | it has been proposed that human immunodeficiency virus type 2 (hiv-2) originated from simian immunodeficiency viruses (sivs) that are natural infections of sooty mangabeys (cercocebus torquatus atys). to test this hypothesis, sivs from eight sooty mangabeys, including six new viruses from west africa, were genetically characterized. gag and env sequences showed that while the viruses of all eight sooty mangabeys belonged to the sivsm/hiv-2 family, each was widely divergent from sivs found earlie ... | 1996 | 8648696 |
| simian immunodeficiency virus variants: threat of new lentiviruses. | infection in humans with the lentivirus hiv-1 typically results in the development of a chronic disease state characterized by the slow decline of cd4+ lymphocytes, the development of immunosuppression, and the development of opportunistic infections, ultimately leading to death. although the average course of disease runs approximately 10 years, shorter and longer progression times have been noted. these alterations are presumed to be, at least partially, a factor of viral variation. the simian ... | 1996 | 8571984 |
| characterization of novel simian immunodeficiency viruses from red-capped mangabeys from nigeria (sivrcmng409 and -ng411). | two novel simian immunodeficiency virus (siv) strains from wild-caught red-capped mangabeys (cercocebus torquatus torquatus) from nigeria were characterized. sequence analysis of the fully sequenced siv strain rcmng411 (sivrcmng411) and gag and pol sequence of sivrcmng409 revealed that they were genetically most closely related to the recently characterized sivrcm from gabon (sivrcmgb1). thus, red-capped mangabeys from distant geographic locations harbor a common lineage of siv. sivrcmng411 carr ... | 2001 | 11711592 |
| isolation and characterization of the first simian immunodeficiency virus from a feral sooty mangabey (cercocebus atys) in west africa. | the lineage of hiv-2-like viruses was studied in feral sooty mangabeys (sms) by serological and genetic methods. four feral sooty mangabeys were positive for simian immunodeficiency virus (siv) antibodies and a new isolate, sivsmsl92a, was obtained. genetic analysis of gag genes showed that sivsmsl92a was highly diverse and a distinct sequence subtype within the siv sm/hiv-2 family. the results showed that sivsm is the most diverse group of sivs found thus far in a single monkey species. | 1995 | 8751049 |
| coreceptor usage of sequential isolates from cynomolgus monkeys experimentally infected with simian immunodeficiency virus (sivsm). | sequential isolates from eight cynomolgus monkeys experimentally infected with simian immunodeficiency virus (sivsm, of sooty mangabey origin) were tested for coreceptor use in the human osteosarcoma indicator cell line, ghost(3), expressing cd4 and one or another of the chemokine receptors ccr3, ccr5, cxcr4, bob, or the orphan receptor bonzo. the indicator cell line carries the human immunodeficiency virus type 2 long terminal repeat-driven green fluorescence protein gene that becomes activated ... | 2001 | 11878872 |
| detection of simian immunodeficiency virus in diverse species and of human immunodeficiency virus type 2 by using consensus primers within the pol region. | human immunodeficiency virus type 2 (hiv-2) is the result of cross-species transmission of simian immunodeficiency virus (siv) from sooty mangabey monkeys to humans. primer pairs (inthiv-2/siv) based on a region of integrase that has considerable homology across hiv-2 and siv lineages were designed to develop a broadly cross-reactive molecular assay to detect lentivirus infection in primates. the inthiv-2/siv primers detect hiv-2 and simian viruses sivcpz, sivsmm, sivsyk, sivagm, and sivmnd. the ... | 2002 | 12202548 |
| immunological and virological studies of natural siv infection of disease-resistant nonhuman primates. | nonhuman primates naturally infected with simian immunodeficiency virus (siv), while maintaining chronic viremia, do not develop any disease associated with lentiviral infection. thus they provide a unique model to define the mechanism(s) by which they remain infected but disease-resistant. the purpose of this article is to summarize our current knowledge of the virological and immunological studies that have been performed in sooty mangabeys naturally infected with sivsmm and in disease-suscept ... | 1996 | 8811346 |
| the history of simian aids. | retrospective data indicate that two separate outbreaks of simian aids and associated lymphoma were caused by simian immunodeficiency virus (sivmac and sivstm, respectively) in group-housed macaques at the california regional primate research center (crprc) in the early and mid-1970s. because these epizootics were not then recognized as infectious in nature, surviving healthy siv carriers were sent to other primate centers where they transmitted the viruses to resident macaques. the source of si ... | 1996 | 8892035 |
| human immunodeficiency virus type 2 (hiv-2) seroprevalence and characterization of a distinct hiv-2 genetic subtype from the natural range of simian immunodeficiency virus-infected sooty mangabeys. | the extent of zoonotic infections in rural sierra leone, where both feral and pet sooty mangabeys harbor divergent members of the human immunodeficiency virus type 2 (hiv-2)-sooty mangabey simian immunodeficiency virus (sivsm) family, was tested in blood samples collected from 9,309 human subjects in 1993. using hiv-1- and hiv-2-specific enzyme immunoassays and confirmatory western blot analysis to test for antibodies to sivsm-related lentiviruses, we found only nine subjects (0.096%) who tested ... | 1997 | 9094672 |
| conservation and host specificity of vpr-mediated cell cycle arrest suggest a fundamental role in primate lentivirus evolution and biology. | the human immunodeficiency virus type 1 (hiv-1) vpr protein prevents infected cells from passing through mitosis by arresting them in the g2 phase of the cell cycle. vpr is conserved among all primate lentiviruses, suggesting an important role in the virus life cycle. moreover, in this study we show that the ability to cause cell cycle arrest is also conserved in vpr proteins from a wide variety of both tissue culture-passaged and uncultured human (hiv-1 and hiv-2), sooty mangabey (simian immuno ... | 1997 | 9151821 |
| uracil dna glycosylase specifically interacts with vpr of both human immunodeficiency virus type 1 and simian immunodeficiency virus of sooty mangabeys, but binding does not correlate with cell cycle arrest. | the vpr protein encoded by human immunodeficiency virus type 1 (hiv-1) is important for growth of virus in macrophages and prevents infected cells from passing into mitosis (g2 arrest). the cellular target for these functions is not known, but vpr of hiv-1 and the related vpr from simian immunodeficiency virus of sooty mangabeys (siv(sm)) bind the dna repair enzyme ung, while the vpx protein of siv(sm) does not. nonetheless, a mutational analysis of vpr showed that binding to ung is neither nece ... | 1997 | 9151883 |
| natural infection of a household pet red-capped mangabey (cercocebus torquatus torquatus) with a new simian immunodeficiency virus. | a seroprevalence survey was conducted for simian immunodeficiency virus (siv) antibody in household pet monkeys in gabon. twenty-nine monkeys representing seven species were analyzed. by using human immunodeficiency virus type 2 (hiv-2)/sivsm, sivmnd, and sivagm antigens, one red-capped mangabey (rcm) (cercocebus torquatus torquatus) was identified as harboring siv-cross-reactive antibodies. a virus isolate, termed sivrcm, was subsequently established from this seropositive rcm by cocultivation ... | 1998 | 9420264 |
| the paradox of simian immunodeficiency virus infection in sooty mangabeys: active viral replication without disease progression. | simian immunodeficiency virus sivsm causes an asymptomatic infection in its natural host, the sooty mangabey, but induces an immunodeficiency syndrome very similar to human aids when transferred to a new host species such as the rhesus macaque. unexpectedly, sivsm replication dynamics is comparable in the two species, with rapid accumulation of viral mutations and a high viral load detected in both mangabeys and macaques. in contrast, clear differences are observed in immune parameters. pathogen ... | 2004 | 14766388 |
| what can natural infection of african monkeys with simian immunodeficiency virus tell us about the pathogenesis of aids? | the simian immunodeficiency viruses are a diverse group of viruses that naturally infect a wide range of african primates, including chimpanzees, african green monkeys (agm) and sooty mangabey monkeys (sm). although natural infection is widespread in feral populations of agms and sms, this infection does not result in immunodeficiency. however, experimental inoculation of asian macaque species results in an immunodeficiency syndrome that is remarkably similar in pathogenesis to human aids. thus, ... | 2004 | 15168740 |
| simian immunodeficiency virus replicates to high levels in sooty mangabeys without inducing disease. | a serologic survey of primates living in a french zoo allowed identification of three cases of infection with simian immunodeficiency virus in sooty mangabeys (cercocebus atys) (sivsm). viral isolates, which were designated sivsmfr66, sivsmfr74, and sivsmfr85, were obtained after short-term culture of mangabey lymphoid cells. phylogenetic analysis of gag and env sequences amplified directly from mangabey tissues showed that the three sivsmfr were genetically close and that they constituted a new ... | 1998 | 9557672 |
| primary sivsm isolates use the ccr5 coreceptor from sooty mangabeys naturally infected in west africa: a comparison of coreceptor usage of primary sivsm, hiv-2, and sivmac. | genetically divergent strains of simian immunodeficiency virus (siv) from macaques (mac), chimpanzees, and sooty mangabeys (sm) efficiently used rhesus and human ccr5 (r5), but not cxcr4 (xr4), for cell entry. thus far, however, no studies have characterized primary sivsm strains for their use of coreceptors derived from their own natural host. coreceptor usage of two primary, blood-derived sivsm isolates, sivsmsl92b and sivsmfns from naturally infected sooty mangabeys, was determined. primary s ... | 1998 | 9656999 |
| different evolution of simian immunodeficiency virus in a natural host and a new host. | to address the mechanisms of host-virus adaptation and pathogenesis of lentiviral infections, we compared the evolution of the same isolate of simian immunodeficiency virus (sivsmm9) in two different situations: nonpathogenic infection of its natural host, the sooty mangabey, and aids-inducing infection of a new host, the rhesus macaque. samples were obtained at 6, 12, and 23 or 30 months postinfection from three animals of each species. sequences were derived from the v1 and v2 domains of the s ... | 1998 | 9683570 |
| parallel evolution of ccr5-null phenotypes in humans and in a natural host of simian immunodeficiency virus. | the c-c chemokine receptor ccr5 in humans and rhesus macaques (macaca mulatta) serves as the primary coreceptor for cellular entry by macrophagetropic strains of human immunodeficiency virus type 1 (hiv-1) and all reported strains of simian immunodeficiency virus (siv) [1-6]. humans homozygous for a 32 bp deletion allele of ccr5, resulting in a null phenotype, are highly resistant to infection by hiv-1 [7-9], prompting development of therapies and vaccines targeting ccr5. we now report a novel d ... | 1998 | 9707408 |
| molecular cloning and expression of rhesus macaque and sooty mangabey interleukin 16: biologic activity and effect on simian immunodeficiency virus infection and/or replication. | interleukin 16 (il-16) has been shown to diminish hiv and siv replication through inhibition of hiv and siv mrna transcription. to evaluate its role further, we compared il-16 cloned from disease-susceptible rhesus macaques and disease-resistant sooty mangabeys. recombinant rhesus macaque (rr) il-16 was compared with recombinant sooty mangabey (rm), human, and other nonhuman primate il-16 sequences and evaluated for its ability to induce chemotaxis and inhibit the mixed lymphocyte response (mlr) ... | 1998 | 9788673 |
| diverse host responses and outcomes following simian immunodeficiency virus sivmac239 infection in sooty mangabeys and rhesus macaques. | sooty mangabeys naturally infected with simian immunodeficiency virus (siv) do not develop immunodeficiency despite the presence of viral loads of 10(5) to 10(7) rna copies/ml. to investigate the basis of apathogenic siv infection in sooty mangabeys, three sooty mangabeys and three rhesus macaques were inoculated intravenously with sivmac239 and evaluated longitudinally for 1 year. sivmac239 infection of sooty mangabeys resulted in 2- to 4-log-lower viral loads than in macaques and did not repro ... | 1998 | 9811693 |
| vpx is required for dissemination and pathogenesis of siv(sm) pbj: evidence of macrophage-dependent viral amplification. | the viral accessory protein vpx is required for productive in vitro infection of macrophages by simian immunodeficiency virus from sooty mangabey monkeys (siv(sm)). to evaluate the roles of vpx and macrophage infection in vivo, we inoculated pigtailed macaques intravenously or intrarectally with the molecularly cloned, macrophage tropic, acutely pathogenic virus siv(sm) pbj 6.6, or accessory gene deletion mutants (deltavpr or deltavpx) of this virus. both wild-type and siv(sm) pbj deltavpx virus ... | 1998 | 9846578 |
| identification of multiple simian immunodeficiency virus (siv)-specific ctl epitopes in sooty mangabeys with natural and experimentally acquired siv infection. | host immune responses to siv infection in sooty mangabeys are likely to be an important determinant of how such nonhuman primate species maintain asymptomatic lentivirus infection. we have previously described two patterns of asymptomatic siv infection in sooty mangabeys: low viral loads with vigorous siv-specific ctl activity in sivmac239-infected sooty mangabeys, and high viral loads with generally weak or absent siv-specific ctl activity in naturally infected sooty mangabeys. to define the sp ... | 2000 | 10623842 |
| normal t-cell turnover in sooty mangabeys harboring active simian immunodeficiency virus infection. | sooty mangabeys naturally infected with simian immunodeficiency virus (siv) remain healthy though they harbor viral loads comparable to those in rhesus macaques that progress to aids. to assess the immunologic basis of disease resistance in mangabeys, we compared the effect of siv infection on t-cell regeneration in both monkey species. measurement of the proliferation marker ki-67 by flow cytometry showed that mangabeys harbored proliferating t cells at a level of 3 to 4% in peripheral blood ir ... | 2000 | 10627531 |
| aids as a zoonosis: scientific and public health implications. | evidence of simian immunodeficiency virus (siv) infection has been reported for 26 different species of african nonhuman primates. two of these viruses, sivcpz from chimpanzees and sivsm from sooty mangabeys, are the cause of acquired immunodeficiency syndrome (aids) in humans. together, they have been transmitted to humans on at least seven occasions. the implications of human infection by a diverse set of sivs and of exposure to a plethora of additional human immunodeficiency virus-related vir ... | 2000 | 10649986 |
| identification of a new hiv-2 subtype based on phylogenetic analysis of full-length genomic sequence. | human immunodeficiency virus type 2 (hiv-2) and simian immunodeficiency virus from sooty mangabey (siv(sm) form one of the six primate lentivirus lineages. the close phylogenetic relationship and geographic coincidence indicate that hiv-2 originated from cross-species transmission of siv(sm) to humans. hiv-2 exhibits considerable genetic diversity, with subtypes a-f identified. previously, we reported the partial gag and env sequences of an unusual hiv-2 isolate, abt96. abt96 was collected in iv ... | 2000 | 10875618 |
| inverse correlation of telomerase activity/proliferation of cd4+ t lymphocytes and disease progression in simian immunodeficiency virus-infected nonhuman primates. | both increased lymphocyte renewal with subsequent exhaustion of the immune system and impaired t-cell renewal have been put forth to account for cd4+ t-cell depletion and development of aids in hiv-1-infected humans and siv-infected nonhuman primates. in the present study, telomeric terminal restriction fragment length and telomerase activity were used as measures of proliferative activity of t lymphocytes from three nonhuman primate species before and after being infected with siv. in periphera ... | 2000 | 10935683 |
| wide range of viral load in healthy african green monkeys naturally infected with simian immunodeficiency virus. | the distribution and levels of simian immunodeficiency virus (siv) in tissues and plasma were assessed in naturally infected african green monkeys (agm) of the vervet subspecies (chlorocebus pygerythrus) by limiting-dilution coculture, quantitative pcr for viral dna and rna, and in situ hybridization for siv expression in tissues. a wide range of siv rna levels in plasma was observed among these animals (<1,000 to 800,000 copies per ml), and the levels appeared to be stable over long periods of ... | 2000 | 11090174 |
| comparative studies on mucosal and intravenous transmission of simian immunodeficiency virus (sivsm): evolution of coreceptor use varies with pathogenic outcome. | coreceptor usage of isolates from 30 cynomolgus macaques infected intrarectally (n=22) or intravenously (n=8) with simian immunodeficiency virus of sooty mangabey origin (sivsm) was evaluated in u87.cd4 and ghost(3) cell lines. based on progression rate, the animals were divided into progressors (18 animals), slow progressors (five animals) and long-term non-progressors (seven animals). there was no difference in how many or which coreceptors were used according to route of infection. all isolat ... | 2006 | 16476979 |
| functional analysis of the simian immunodeficiency virus vpx protein: identification of packaging determinants and a novel nuclear targeting domain. | the vpx gene products of human immunodeficiency virus type 2 (hiv-2) and of the closely related simian immunodeficiency viruses from sooty mangabeys (sivsm) and macaques (sivmac) comprise a 112-amino-acid virion-associated protein that is critical for efficient virus replication in nondividing cells such as macrophages. when expressed in the absence of other viral proteins, vpx localizes to the nuclear membrane as well as to the nucleus; however, in the context of virus replication vpx is packag ... | 2001 | 11119605 |
| relative resistance in the development of t cell anergy in cd4+ t cells from simian immunodeficiency virus disease-resistant sooty mangabeys. | despite high viral loads, t cells from sooty mangabey (sm) monkeys that are naturally infected with siv but remain clinically asymptomatic, proliferate and demonstrate normal ag-specific memory recall cd4(+) t cell responses. in contrast, cd4(+) t cells from rhesus macaques (rm) experimentally infected with siv lose ag-specific memory recall responses and develop immunological anergy. to elucidate the mechanisms for these distinct outcomes of lentiviral infection, highly enriched alloreactive cd ... | 2001 | 11123330 |
| simian immunodeficiency viruses replication dynamics in african non-human primate hosts: common patterns and species-specific differences. | to define potential common features of simian immunodeficiency virus (siv) infections in different naturally infected host species, we compared the dynamics of viral replication in 31 african green monkeys (10 sabeus, 15 vervets and seven caribbean agms), 14 mandrills and three sooty mangabeys (sms) that were experimentally infected with their species-specific viruses. | 2006 | 16872282 |
| paucity of cd4+ccr5+ t cells is a typical feature of natural siv hosts. | in contrast to lentiviral infections of humans and macaques, simian immunodeficiency virus (siv) infection of natural hosts is nonpathogenic despite high levels of viral replication. however, the mechanisms underlying this absence of disease are unknown. here we report that natural hosts for siv infection express remarkably low levels of ccr5 on cd4+ t cells isolated from blood, lymph nodes, and mucosal tissues. given that this immunologic feature is found in 5 different species of natural siv h ... | 2007 | 17003371 |
| identification of protein kinases dysregulated in cd4(+) t cells in pathogenic versus apathogenic simian immunodeficiency virus infection. | human immunodeficiency virus infection in humans and simian immunodeficiency virus (siv) infection in rhesus macaques (rm) leads to a generalized loss of immune responses involving perturbations in t-cell receptor (tcr) signaling. in contrast, naturally siv-infected sooty mangabeys (sm) remain asymptomatic and retain immune responses despite relatively high viral loads. however, siv infection in both rm and sm led to similar decreases in tcr-induced lck phosphorylation. in this study, a protein ... | 2001 | 11689610 |
| emergence of cytotoxic t lymphocyte escape mutations in nonpathogenic simian immunodeficiency virus infection. | although ctl escape has been well documented in pathogenic simian immunodeficiency virus (siv) infection, there is no information on ctl escape in nonpathogenic siv infection in nonhuman primate hosts like the sooty mangabeys. ctl responses and sequence variation in the siv nef gene were evaluated in one sooty mangabey and one rhesus macaque inoculated together with the same stock of cloned sivmac239. each animal developed an immunodominant response to a distinct ctl epitope in nef, aa 157-167 i ... | 2001 | 11745337 |
| noninvasive detection of new simian immunodeficiency virus lineages in captive sooty mangabeys: ability to amplify virion rna from fecal samples correlates with viral load in plasma. | the sooty mangabey (sm) (cercocebus atys) is the natural host of a simian immunodeficiency virus, termed sivsm, which gave rise to human immunodeficiency virus type 2. data on the geographic distribution, prevalence, and genetic diversity of sivsm in the wild remains limited. to address this issue, noninvasive strategies based on screening sm fecal and urine specimens for sivsm-specific antibodies and virion rna (vrna) were developed, and the results were correlated with viral loads in plasma. t ... | 2003 | 12525656 |
| simian immunodeficiency viruses from multiple lineages infect human macrophages: implications for cross-species transmission. | zoonotic transfer of simian immunodeficiency virus (siv) from chimpanzees and sooty mangabeys to humans has been documented on at least seven occasions. several recently identified siv isolates have also been shown to replicate efficiently in human peripheral blood mononuclear cells (pbmcs) in vitro, indicative of the potential for additional cross-species transmission via t cell infection. although siv predominantly uses the macrophage-tropic hiv chemokine coreceptor ccr5, little is known about ... | 2003 | 12640192 |
| decreased ccr5 expression on cd4+ t cells of siv-infected sooty mangabeys. | sooty mangabeys are the natural host of simian immunodeficiency virus (sivsm). when injected into rhesus macaques, sivsm infection results in progressive declines in cd4(+) t cells, opportunistic infections, and aids. in contrast, siv-infected sooty mangabeys do not develop disease and live an apparently normal life span in captivity, despite maintaining high levels of virus in plasma throughout their lives. determining the mechanisms by which sooty mangabeys have evolved to resist disease progr ... | 2003 | 12689415 |
| elevated interleukin-7 levels not sufficient to maintain t-cell homeostasis during simian immunodeficiency virus-induced disease progression. | elevated levels of interleukin 7 (il-7) have been correlated with various t-cell depletion conditions, including hiv infection, and suggested as an indicator of hiv disease progression (aids and death). here, the assessment of pathogenic simian immunodeficiency virus (sivmac239) infection in rhesus macaques demonstrated a clear association between a significant elevation in il-7 levels and disease progression. in 5 macaques that progressed to simian aids and death, elevated il-7 levels were unab ... | 2004 | 14525780 |
| dysregulation of the polo-like kinase pathway in cd4+ t cells is characteristic of pathogenic simian immunodeficiency virus infection. | cd4(+) t-cell dysfunction highlighted by defects within the intracellular signaling cascade and cell cycle has long been characterized as a direct and/or indirect consequence of human immunodeficiency virus (hiv) infection in humans and simian immunodeficiency virus (siv) infection in rhesus macaques (rm). dysregulation of the m phase of the cell cycle is a well-documented effect of hiv or siv infection both in vivo and in vitro. in this study the effect of siv infection on the modulation of two ... | 2004 | 14722302 |
| a brief history of the discovery of natural simian immunodeficiency virus (siv) infections in captive sooty mangabey monkeys. | experimental leprosy studies using mycobacterium leprae inoculum isolated from a sooty mangabey monkey (smm) resulted in the accidental discovery that smm's asymptomatically carry simian immunodeficiency virus (siv) that is pathogenic in macaques. we showed that the smm virus, sivdelta, was antigenically related to sivmac, which had been identified in macaques, and to the human immunodeficiency virus (hiv). similar asymptomatic natural siv infections had been reported in african green monkeys (a ... | 2004 | 14766361 |
| classic aids in a sooty mangabey after an 18-year natural infection. | prevailing theory holds that simian immunodeficiency virus (siv) infections are nonpathogenic in their natural simian hosts and that lifelong infections persist without disease. numerous studies have reported that siv-infected sooty mangabeys (sms; cercocebus atys) remain disease free for up to 24 years despite relatively high levels of viral replication. here, we report that classic aids developed after an 18-year incubation in an sm (e041) with a natural sivsm infection. unlike that described ... | 2004 | 15280498 |
| humoral immunity and the evolution of hiv-2. | human immunodeficiency virus type 2 (hiv-2) evolved from the zoonotic transmission of simian immunodeficiency virus (siv) that naturally infects sooty mangabeys found in west africa. using sera from hiv-2-infected humans, we discovered that an hypervariable region (the v4 loop) of hiv-2 induces antibody responses only weakly reactive against itself but strongly reactive against analogous sequences from the v4 loop of strains of siv. available sequence data indicates that all strains of hiv-2 hav ... | 2004 | 15357909 |
| direct inoculation of simian immunodeficiency virus from sooty mangabeys in black mangabeys (lophocebus aterrimus): first evidence of aids in a heterologous african species and different pathologic outcomes of experimental infection. | a unique opportunity for the study of the role of serial passage and cross-species transmission was offered by a series of experiments carried out at the tulane national primate research center in 1990. to develop an animal model for leprosy, three black mangabeys (bkms) (lophocebus aterrimus) were inoculated with lepromatous tissue that had been serially passaged in four sooty mangabeys (sms) (cercocebus atys). all three bkms became infected with simian immunodeficiency virus from sms (sivsm) b ... | 2004 | 15479792 |
| molecular epidemiology of simian t-cell lymphotropic virus type 1 in wild and captive sooty mangabeys. | a study was conducted to evaluate the prevalence and diversity of simian t-cell lymphotropic virus (stlv) isolates within the long-established tulane national primate research center (tnprc) colony of sooty mangabeys (sms; cercocebus atys). serological analysis determined that 22 of 39 animals (56%) were positive for stlv type 1 (stlv-1). a second group of thirteen sm bush meat samples from sierra leone in africa was also included and tested only by pcr. twenty-two of 39 captive animals (56%) an ... | 2005 | 15681454 |
| detection and partial characterization of simian immunodeficiency virus sivsm strains from bush meat samples from rural sierra leone. | human immunodeficiency virus type 2 (hiv-2) originated from simian immunodeficiency viruses (sivs) that naturally infect sooty mangabeys (sms; cercocebus atys). in order to further investigate the relationship between hiv-2 and sivsm, the siv specific to the sm, we characterized seven new sivsm strains from sms sold in sierra leone markets as bush meat. the gag, pol, and env sequences showed that, while the viruses of all seven sms belonged to the sivsm-hiv-2 lineage, they were highly divergent ... | 2005 | 15681464 |
| divergent host responses during primary simian immunodeficiency virus sivsm infection of natural sooty mangabey and nonnatural rhesus macaque hosts. | to understand how natural sooty mangabey hosts avoid aids despite high levels of simian immunodeficiency virus (siv) sivsm replication, we inoculated mangabeys and nonnatural rhesus macaque hosts with an identical inoculum of uncloned sivsm. the unpassaged virus established infection with high-level viral replication in both macaques and mangabeys. a species-specific, divergent immune response to siv was evident from the first days of infection and maintained in the chronic phase, with macaques ... | 2005 | 15767406 |
| molecular epidemiology of simian immunodeficiency virus sivsm in u.s. primate centers unravels the origin of sivmac and sivstm. | retrospective molecular epidemiology was performed on samples from four sooty mangabey (sm) colonies in the united states to characterize simian immunodeficiency virus sivsm diversity in sms and to trace virus circulation among different primate centers (pcs) over the past 30 years. the following sivsm sequences were collected from different monkeys: 55 sivsm isolates from the tulane pc sampled between 1984 and 2004, 10 sivsm isolates from the yerkes pc sampled in 2002, 7 sivsm isolates from the ... | 2005 | 15994793 |
| primary sooty mangabey simian immunodeficiency virus and human immunodeficiency virus type 2 nef alleles modulate cell surface expression of various human receptors and enhance viral infectivity and replication. | the nef gene of the pathogenic simian immunodeficiency virus (siv) mac239 clone has been well characterized. little is known, however, about the function of nef alleles derived from naturally sivsm-infected sooty mangabeys (cercocebus atys) and from human immunodeficiency virus type 2 (hiv-2)-infected individuals. addressing this, we demonstrate that, similarly to the sivmac239 nef, primary sivsm and hiv-2 nef alleles down-modulate cell surface expression of human cd4, cd28, cd3, and class i or ... | 2005 | 16051847 |
| timely triggering of homeostatic mechanisms involved in the regulation of t-cell levels in sivsm-infected sooty mangabeys. | sooty mangabeys, the natural host of simian immunodeficiency virus (sivsm), generally avoid progressive depletion of cd4+ t cells and opportunistic infections associated with infection of humans (hiv) and macaques (sivmac). the means by which the sivsm-infected mangabeys maintain cd4+ t-cell levels despite high rates of viral replication is unknown. one cytokine that has a key role in the regulation of t-cell levels is interleukin-7 (il-7). here, the longitudinal assessment of 6 sivsm-infected m ... | 2005 | 16105985 |
| differential restriction of human immunodeficiency virus type 2 and simian immunodeficiency virus sivmac by trim5alpha alleles. | primate lentiviruses have narrow host ranges, due in part to their sensitivities to mammalian intracellular antiviral factors such as apobec3g and trim5alpha. despite the protection provided by this innate immune system, retroviruses are able to transfer between species where they can cause disease. this is true for sooty mangabey simian immunodeficiency virus, which has transferred to humans as hiv-2 and to rhesus macaques as sivmac, where it causes aids. here we examine the sensitivities of th ... | 2005 | 16140735 |