Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| induction of antibodies against siv antigens after intramuscular nucleic acid inoculation using complex expression constructs. | by studying the infection of rhesus macaques with simian immunodeficiency virus (sivmac) the potential of nucleic acid immunisation against aids can be evaluated. as a first step towards the development of suitable expression constructs, the levels and the durations of expression elicited by the house-keeping gene promoters of the murine phospho-glycerate kinase (pgk) gene and rat proto-ras 1ha, a lentiviral ltr and the cmv-intron a promoter were tested in balb/c mice intramuscularly inoculated ... | 1996 | 8717387 |
| 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 |
| interferon-gamma expression in macaque lymph nodes during primary infection with simian immunodeficiency virus. | simian immunodeficiency virus (siv) replication is rapidly downregulated in the lymph nodes (ln) of rhesus macaques after the acute stage of primary infection. the aim of this study was to evaluate a possible role of interferon-gamma (ifn-gamma) in the control of siv replication. ifn-gamma expression was analysed by in situ hybridization in the ln of rhesus macaques that were inoculated either with a high dose or with a low dose of the pathogenic isolate sivmac 251. the kinetics of ifn-gamma ind ... | 1996 | 9047081 |
| rapid development of vaccine protection in macaques by live-attenuated simian immunodeficiency virus. | convincing data on experimental vaccines against aids have been obtained in the simian immunodeficiency virus (siv) macaque model by preinfection with a virus attenuated by a nef deletion. to investigate the efficacy of a nef deletion mutant of sivmac32h called pc8 as a live-attenuated vaccine after shorter preinfection periods and to learn more about the nature of the immune protection induced, eight rhesus monkeys were infected intravenously with the pc8 virus. all monkeys became persistently ... | 1996 | 9000087 |
| progesterone-hiv link questioned by new studies. | several small studies conducted by the centers for disease control and prevention (cdc) have shown that although progesterone appears to increase the likelihood of simian immunodeficiency virus (siv) transmission in exposed monkeys, women using hormone contraceptives do not appear to have the same increased risk for hiv. the results, published in the may issue of science, show little, if any, increase in the rate of hiv infection in women on depo-provera, an injectable contraception containing p ... | 1996 | 11363549 |
| the riddle of oral sex. | oral sex continues to be a source of confusion in determining its risk for hiv transmission. educator dave nimmons concludes that oral sex offers a possible, but very low, risk of hiv infection and states that much of the concern about oral sex and hiv prevention centers around two dozen cases of single occurrences of oral transmission from all over the world. many researchers believe that knowledge about this small number of cases facilitates informed decisions about risk and demonstrates under ... | 1996 | 11363848 |
| intrarectal transmission of simian immunodeficiency virus in rhesus macaques: selective amplification and host responses to transient or persistent viremia. | intrarectal simian immunodeficiency virus (siv) infection in rhesus macaques is a model for sexual transmission of primate retroviruses. phylogenetic studies on envelope gene sequences that were present in blood following intrarectal siv inoculation provided evidence for selective amplification of a subset of viruses present in the inoculum and defined one amino acid sequence uniquely associated with intrarectal infection. both persistent and transient viremia states were observed after intrarec ... | 1996 | 8794330 |
| a chimeric simian/human immunodeficiency virus expressing a primary patient human immunodeficiency virus type 1 isolate env causes an aids-like disease after in vivo passage in rhesus monkeys. | the utility of the simian immunodeficiency virus of macaques (sivmac) model of aids has been limited by the genetic divergence of the envelope glycoproteins of human immunodeficiency virus type 1 (hiv-1) and the sivs. to develop a better aids animal model, we have been exploring the infection of rhesus monkeys with chimeric simian/human immunodeficiency viruses (shivs) composed of sivmac239 expressing hiv-1 env and the associated auxiliary hiv-1 genes tat, vpu, and rev. shiv-89.6, constructed wi ... | 1996 | 8794335 |
| definition of human immunodeficiency virus type 1 gp120 and gp41 cytotoxic t-lymphocyte epitopes and their restricting major histocompatibility complex class i alleles in simian-human immunodeficiency virus-infected rhesus monkeys. | with the development of chimeric simian-human immunodeficiency virus (shiv)-infected macaques as a model for assessing novel human immunodeficiency virus type i (hiv-1) envelope glycoprotein (env)-based vaccine strategies for preventing hiv-1 infection in man, it will be important to determine hiv-1 env-specific cytotoxic t-lymphocyte (ctl) responses in vaccinated and virus-infected monkeys. to facilitate performing such ctl studies, we have defined two hiv-1 env ctl epitopes in shiv-infected rh ... | 1996 | 8794394 |
| rhesus thymic/liver xenografts in severe combined immunodeficient mice: immunologic reconstitution and intrathymic infection with simian immunodeficiency virus. | by serving as host recipients of xenografts from both humans and animals, severe combined immunodeficient (scid) mice have become valuable to many laboratories interested in examining the pathophysiology of different diseases. to gain insight into the usefulness of the scid mutation in retrovirus research, rhesus monkey fetal hematolymphoid tissues (liver and thymus) were used to construct a scid-rhesus chimeric mouse (scid-rh) and were engrafted in the renal capsule. the size and maturation of ... | 1996 | 8804357 |
| fetal or neonatal infection with attenuated simian immunodeficiency virus results in protective immunity against oral challenge with pathogenic sivmac251. | we have reported that infection of fetal or neonatal rhesus macaques with attenuated sivmac1a11 results in transient viremia, anti-siv antibody responses, weak or absent cytotoxic t-lymphocyte responses, and no clinical disease. in light of these results, we hypothesized that congenital infection with sivmac1a11 produced immune tolerance to siv. to test this hypothesis, at approximately 1 year of age, five rhesus macaques infected with sivmac1a11 as fetuses (n = 3) or newborns (n = 2) and five n ... | 1996 | 8806509 |
| 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 |
| attenuated siv imparts immunity to challenge with pathogenic spleen-derived siv but cannot prevent repair of the nef deletion. | to date, some success has been achieved with several experimental vaccines against aids in the available animal models. in the simian immunodeficiency virus (siv) macaque model protection against superinfection was obtained by preinfection with a virus attenuated by a deletion in nef. to investigate the efficacy of sivmac32h(pc8), a nef deletion mutant of sivmac251, as a live-attenuated vaccine, rhesus monkeys were infected intravenously (i.v.) with this virus. all monkeys became productively in ... | 1996 | 8811357 |
| virus-induced immunosuppression is linked to rapidly fatal disease in infant rhesus macaques infected with simian immunodeficiency virus. | six newborn rhesus macaques were experimentally infected with pathogenic simian immunodeficiency virus of macaques (sivmac251), and three newborn macaques were infected with avirulent sivmac1a11. the former developed rapidly fatal simian aids and died within 26 wk of age, whereas the latter remained clinically normal. infant monkeys that developed rapidly progressive disease had rapid declines in cd4+ cells and were unable to mount igg and iga antibody responses to siv or to an unrelated antigen ... | 1996 | 8848337 |
| safety of 9-(2-phosphonylmethoxyethyl)adenine (pmea) in patients with human immunodeficiency virus infection: a pilot study. | the compound 9-(2-phosphonylmethoxyethyl)adenine (pmea) is a potent inhibitor of a number of viruses in vitro such as human immunodeficiency virus types 1 and 2, herpes simplex virus types 1 and 2, hepatitis b virus, cytomegalovirus, and epstein-barr virus. pmea also proved to be effective in vivo against feline immunodeficiency virus in cats and simian immunodeficiency virus in rhesus monkeys. in an open, non-placebo-controlled trial, the safety of weekly doses of pmea in 10 patients with acqui ... | 1996 | 8861829 |
| localization of simian immunodeficiency virus nucleic acid and antigen in brains of fetal macaques inoculated in utero. | neurological dysfunction has been shown to be associated with human immunodeficiency virus (hiv) infection. the incidence of these abnormalities is greater in hiv-infected children when compared with adults, and the patterns of neurological disease are also known to differ from those observed in the adult population. the reasons for these differences are unclear but are most likely related to the immaturity of the host's immune and central nervous systems at the time of infection. this is though ... | 1996 | 8863658 |
| the effect of recombinant human interferon alpha b/d compared to interferon alpha 2b on siv infection in rhesus macaques. | the model of simian immunodeficiency virus (siv) infection in rhesus macaques was used to evaluate the effects of recombinant human interferon alpha, hu ifn-alpha 2b and hu ifn-gamma b,d, at two doses. administration began 1 day prior to infection and was continued for 90 days postinfection. both interferons suppressed siv antigenemia during the treatment period. following treatment animals were monitored for 4 years for rate of disease progression. neither ifn prolonged the asymptomatic period ... | 1996 | 8863990 |
| the relationship between the interferon alpha response and viral burden in primary siv infection. | the interferon alpha (ifn-alpha) response of rhesus macaques was investigated during primary infection with pathogenic and attenuated simian immunodeficiency virus (siv). ifn-alpha was detected in the serum of animals as early as day 4 after inoculation of sivmac251, but remained barely detected in animals infected with the attenuated virus sivmac251 delta nef. the peak of ifn-alpha secretion preceded that of antigenemia in animals infected with pathogenic virus, indicating that the ifn-alpha re ... | 1996 | 8870849 |
| the v3 domain of sivmac251 gp120 contains a linear neutralizing epitope. | antisera to 21 synthetic peptides containing hydrophilic sequences of simian immunodeficiency virus strain mac251 (sivmac251) gp120 and gp32 were tested for the ability to neutralize sivmac251. goat antisera raised to peptides sp-1 and sp-1v containing the carboxy-terminal portion of the v3 domain of sivmac251 gp120 between amino acids 327 and 339 inhibited syncytium formation (90% inhibition at a 1/1024 dilution) and cell killing of cemx174 cells by sivmac251 (50%) inhibition of cell killing at ... | 1996 | 8874502 |
| cytotoxic t-lymphocyte responses to cytomegalovirus in normal and simian immunodeficiency virus-infected rhesus macaques. | disseminated cytomegalovirus (cmv) infection is a frequent occurrence in human immunodeficiency virus-infected humans and in simian immunodeficiency virus (siv)-infected rhesus macaques. rhesus macaques are a suitable animal model with which to study in vivo interactions between cmv and aids-associated retroviruses. since cytotoxic t lymphocytes (ctl) play a major role in control of viral infections, we have characterized cmv-specific ctl responses in siv-infected and uninfected rhesus macaques. ... | 1996 | 8892893 |
| expression of inflammatory cytokines and inducible nitric oxide synthase in brains of siv-infected rhesus monkeys: applications to hiv-induced central nervous system disease. | human immunodeficiency virus type 1 (hiv-1) infection of the central nervous system (cns) can lead to severe impairments in cognition, behavior, and motor skills. the mechanism(s) by which hiv-1 induces cns disease are not well understood. recent evidence suggests that expression of inducible nitric oxide synthase (inos) and nitric oxide (no) may contribute to hiv-1-induced neurologic disease. we sought to determine if these factors were present in the cns of rhesus monkeys with simian immunodef ... | 1996 | 8900532 |
| the nef gene from a long-term hiv type 1 nonprogressor. | we examined the nef gene of hiv-1 in a long-term nonprogressor to look for evidence suggesting an attenuated virus. the nef gene was previously shown to be required for induction of aids. simian immunodeficiency virus (siv) deleted in nef, while infectious, fails to sustain the high viral loads necessary for the induction of aids in infected adult rhesus monkeys. the human subject of this report was found to harbor virus (hiv-1 sur25) encoding open-nef reading frames. however, the nef genes of t ... | 1996 | 8906995 |
| 9-[2-(phosphonomethoxy)propyl]adenine therapy of established simian immunodeficiency virus infection in infant rhesus macaques. | the long-term therapeutic and toxic effects of 9-[2-(phosphonomethoxy)propyl]adenine (pmpa) were evaluated in simian immunodeficiency virus (siv)-infected newborn rhesus macaques. four untreated siv-infected newborn macaques developed persistently high levels of viremia, and three of the four animals had rapidly fatal disease within 3 months. in contrast, long-term pmpa treatment of four newborn macaques starting 3 weeks after virus inoculation resulted in a rapid, pronounced, and persistent red ... | 1996 | 8913470 |
| nature and sequence of simian immunodeficiency virus-induced central nervous system lesions: a kinetic study. | to determine the onsets and specificities of neuropathological features observed after simian immunodeficiency virus (siv) infection of macaques, brains of 19 clinically unaffected rhesus monkeys (group a) were examined after intervals ranging from 1 to 48 weeks post-infection and compared to 8 animals with aids (group b) as well as to 8 uninfected controls. based on morphological and virological parameters, seven patterns specific for siv infection of the central nervous system (cns) were disce ... | 1996 | 8922061 |
| similar abnormalities of idiotype and immunoglobulin light chain expression and of cell-mediated cytotoxicity in hiv-infected humans and simian immunodeficiency virus (siv)-infected rhesus macaques. | the pathogenesis of aids in simian immunodeficiency virus (siv)-infected rhesus macaques models the pathogenesis of human aids. we investigated whether certain immunological abnormalities associated with hiv infection and implicated in disease progression also occur in siv infection. we observed striking parallels between the rhesus macaque humoral immune response to siv and unusual features of the human humoral immune response to hiv infection. anti-siv envelope antibodies from siv-infected mac ... | 1996 | 8934652 |
| activation of pak by hiv and siv nef: importance for aids in rhesus macaques. | the primate lentiviruses, human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) and simian immunodeficiency virus (siv), encode a conserved accessory gene product, nef. in vivo, nef is important for the maintenance of high virus loads and progression to aids in siv-infected adult rhesus macaques. in tissue culture cells expressing nef, this viral protein interacts with a cellular serine kinase, designated nef-associated kinase. | 1996 | 8939608 |
| microglia-passaged simian immunodeficiency virus induces neurophysiological abnormalities in monkeys. | four rhesus macaques were inoculated intravenously with a cryopreserved stock of microglia obtained from a simian immunodeficiency virus (siv)-infected rhesus macaque. before infection, three of the four monkeys were trained and tested daily on a computerized neuropsychological test battery. after siv infection, behavioral testing continued to monitor deficits associated with disease progression. five additional age-matched, behaviorally trained monkeys served as controls. neurophysiological tes ... | 1996 | 8943077 |
| temporal association of interferon-alpha and p27 core antigen levels in sera of simian immunodeficiency virus infected monkeys. | we report the temporal association of interferon (ifn) and p27 core antigen production during experimental simian immunodeficiency virus delta b670 (siv) infection in rhesus monkeys. peak serum ifn-alpha levels (10(2.8-5.0)u/ml) occurred 10 days post infection (p.i.) and peak p27 levels (3.1-34.4 ng/ml) occurred 10-14 days p.i. acid-stable ifn-alpha (10(1.6-2.5)u/ml) was detected 3-5 days before p27 in sera from three monkeys and was detected with p27 (0.06-3.06 ng/ml) in four monkeys during the ... | 1996 | 8965677 |
| neuroinvasion by simian immunodeficiency virus coincides with increased numbers of perivascular macrophages/microglia and intrathecal immune activation. | during peak viremia and initial antibody response, rhesus macaques infected with pathogenic and nonpathogenic isolates of siv show distinct differences in viral load and tissue distribution. animals infected with pathogenic isolates of siv invariably have virus in the csf and brain parenchyma by two weeks postinoculation, whereas animals infected with nonpathogenic isolates do not. mechanisms underlying neuroinvasion by siv and hiv are unknown, but recruitment of latently infected mononuclear ce ... | 1996 | 8972425 |
| simian immunodeficiency virus-specific cytotoxic t-lymphocyte induction through dna vaccination of rhesus monkeys. | in view of the growing evidence that virus-specific cytotoxic t lymphocytes (ctl) play an important role in containing the early spread of human immunodeficiency virus type 1 (hiv-1) in infected individuals, novel vaccine strategies capable of eliciting hiv-1-specific ctl are being pursued in attempts to create an effective aids vaccine. we have used the simian immunodeficiency virus of macaques (sivmac)/rhesus monkey model to explore the induction of aids virus-specific ctl responses by dna vac ... | 1996 | 8523593 |
| cellular targets of infection and route of viral dissemination after an intravaginal inoculation of simian immunodeficiency virus into rhesus macaques. | we used the simian immunodeficiency virus (siv)/rhesus macaque model to study events that underlie sexual transmission of human immunodeficiency virus type 1 (hiv-1). four female rhesus macaques were inoculated intravaginally with sivmac251, and then killed 2, 5, 7, and 9 d later. a technique that detected polymerase chain reaction-amplified siv in situ showed that the first cellular targets for siv were in the lamina propria of the cervicovaginal mucosa, immediately subjacent to the epithelium. ... | 1996 | 8551225 |
| the t cell receptor gene usage by simian immunodeficiency virus gag-specific cytotoxic t lymphocytes in rhesus monkeys. | mhc class i-restricted ctl play an important role in limiting the spread of hiv-1 in the infected individual. elucidating the molecular interactions of ctl with the virus is, therefore, of central importance for characterizing the immune control of this infection. in exploring this ctl response, we have defined the tcr usage by sivmac gag-specific ctl in rhesus monkeys. thirty-nine ctl clones were generated from pbl of three sivmac-infected monkeys expressing the mhc class i mamu-a*01 gene produ ... | 1996 | 8568249 |
| does progesterone increase hiv risk? contraceptive update. | the recent finding that rhesus monkeys given progesterone were more likely to become infected after vaginal exposure to simian immunodeficiency virus than their nontreated counterparts has raised concerns about the effect of progestin-containing contraceptives on hiv risk. more research is needed to determine whether this finding extends to the progestins used in oral contraceptives, norplant, injectables, and the levonorgestrel-containing iud. family health international, in response to the a ... | 1996 | 12291587 |
| hormonal contraceptives and the risk of stds. | a recent national institutes of health (nih)-funded study indicating that rhesus monkeys implanted with long-acting progesterone pellets were more likely to become infected after vaginal exposure to simian immunodeficiency virus (siv) than their nontreated counterparts has raised concerns about the contribution of hormonal contraception to sexually transmitted disease (std) risk. 14 of 18 monkeys treated with progesterone, compared with only 1 of 10 controls, developed siv. researchers specula ... | 1996 | 12291588 |
| simian immunodeficiency virus-inoculated macaques acquire mycobacterium avium from potable water during aids. | during the terminal stages of aids, mycobacterium avium complex (mac) infection is the most common disseminated bacterial infection in rhesus macaques (macaca mulatta) experimentally inoculated with the simian immunodeficiency virus (siv). the source of mycobacterial infection in 15 siv-inoculated rhesus macaques housed in a biolevel 3 containment facility was investigated using a sensitive polymerase chain reaction typing technique. six animal isolates had banding profiles identical to that of ... | 1997 | 8985217 |
| plasma viremia in macaques infected with simian immunodeficiency virus: plasma viral load early in infection predicts survival. | a reliable method for the quantitation of plasma viremia in nonhuman primates infected with simian immunodeficiency virus (siv) and related viruses is described. this method is based on an established quantitative-competitive pcr format and includes a truncated control for internal assay calibration. optimization of assay conditions has significantly improved amplification specificity, and interassay variability is comparable to that of commercially available assays for human immunodeficiency vi ... | 1997 | 8985348 |
| expression of gamma interferon by simian immunodeficiency virus increases attenuation and reduces postchallenge virus load in vaccinated rhesus macaques. | simian immunodeficiency virus (siv) infection of macaques is a model for human immunodeficiency virus (hiv) infection. we have previously reported the construction and characterization of an siv vector with a deletion in the nef gene (siv(delta nef)) and expressing gamma interferon (siv(hyifn)) (l. giavedoni and t. yilma, j. virol. 70:2247-2251, 1996). we now show that rhesus macaques vaccinated with siv(hyifn) have a lower viral load than a group similarly immunized with siv(delta nef). viral l ... | 1997 | 8995602 |
| 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 |
| a zidovudine-resistant simian immunodeficiency virus mutant with a q151m mutation in reverse transcriptase causes aids in newborn macaques. | the simian immunodeficiency virus (siv)-newborn rhesus macaque model of aids can be used to study directly the virulence of viral mutants which are resistant to antiviral drugs. a viral mutant called sivmac79a6.1, isolated from an siv-infected macaque after prolonged zidovudine treatment, was found to have a double-base-pair change at codon 151 of reverse transcriptase, resulting in a glutamine to methionine substitution (q151m). this mutation was associated with more than 100-fold increased res ... | 1997 | 9021180 |
| efficacy of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg) on an arc/aids rhesus macaque (macaca mulatta) infected with simian immunodeficiency virus. | the efficacy of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg) was investigated in vivo by using a male arc/aids rhesus macaque infected with simian immunodeficiency virus (sivmac251/32h). he was administered subcutaneously 6-cl-ddg (50 mg/kg b.w.) every 8 hr for 14 days when he showed clinical features of recurrent weight loss, severe diarrhea and neuropathy. the number of cd4+, cd8+ cells and total t cells increased rapidly after administration of 6-cl-ddg and a high level was maintained for 2 mon ... | 1997 | 9027477 |
| disseminated granulomatous disease in a simian immunodeficiency virus- and bacille calmette-guèrin-infected rhesus monkey. | 1997 | 9030386 | |
| induction of aids by simian immunodeficiency virus lacking nf-kappab and sp1 binding elements. | rhesus monkeys (macaca mulatta) were infected with five strains of simian immunodeficiency virus (siv) derived from sivmac239 containing deletions (delta) or substitutions (subst) in nf-kappab and sp1 binding sites. we have shown previously that mutations in these regions still allow efficient sivmac replication in primary lymphoid cell cultures (p. o. ilyinskii and r. c. desrosiers, j. virol. 70:3118-3126, 1996). two animals were inoculated intravenously with each mutant strain of sivmac239: de ... | 1997 | 9032318 |
| construction, replication, and immunogenic properties of a simian immunodeficiency virus expressing interleukin-2. | to study the effect of interleukin-2 (il-2) on simian immunodeficiency virus (siv) replication, pathogenesis, and immunogenicity, we replaced the nef gene of sivmac239 by the il-2 coding region. the virus, designated siv-il2, stably expressed high levels of il-2 in cell culture. in comparison to sivmac239, siv-il2 replicated more efficiently in peripheral blood mononuclear cells in the absence of exogenously added il-2. to determine whether this growth advantage would be of relevance in vivo, fo ... | 1997 | 9032357 |
| efficacy of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg) on rhesus macaque monkeys chronically infected with simian immunodeficiency virus (sivmac239). | to assess the therapeutic effects of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg), a lipophilic dideoxynucleoside analogue, three rhesus macaques chronically infected with simian immunodeficiency virus (sivmac239) were subcutaneously administered 25 mg/kg of the drug every 8 hours for 2 weeks. in two of three animals, the viral rna in plasma and the cell-associated viral load from peripheral blood mononuclear cells were markedly decreased and the number of cd4+ and cd8+ lymphocytes were increased ... | 1997 | 9420307 |
| cytokine gene transcription in simian immunodeficiency virus and human immunodeficiency virus-associated non-hodgkin lymphomas. | infection of rhesus monkeys with siv leads to aids-like symptoms. similar to human aids patients, some monkeys develop b cell non-hodgkin lymphoma (nhl). we determined transcription of cytokine genes regulating the activation of b and t cells, which play a role in intratumoral immune surveillance. therefore, we compared the transcription of the cytokine genes encoding il-2, il-4, il-6, il-10, ifn-gamma, tnf-alpha, and tgf-beta1, and the epstein-barr virus-encoded bcrf 1 gene, in cells from five ... | 1997 | 9430251 |
| the role of skin dendritic cells in the initiation of human immunodeficiency virus infection. | human immunodeficiency virus (hiv) can be transmitted by accidental puncture with needles containing hiv-contaminated blood. however, the molecular and cellular interactions that occur between hiv and cells of the skin following percutaneous needlestick injury are unknown. direct inoculation of exogenous virus into recipient blood vessels of the dermis is possible. in addition, skin dendritic cells (dc; e.g., epidermal langerhans cells, dermal dc, lymphatic veiled cells) may also play a role in ... | 1997 | 9845491 |
| threat to humans from virus infections of non-human primates. | several hundred distinct non human primate species are recognised, and they are likely to harbour a similar range of viruses to humans. simians such as cynomolgus and rhesus macaques, african green monkeys, and marmosets are widely used for biomedical research, but despite this extensive close contact very few simian viruses have been shown to pose a threat of infection or illness to humans. herpesvirus simiae is the best recognised zoonotic hazard of simians. it is an alphaherpes virus of asiat ... | 1997 | 10398488 |
| transduction of cd34+ hematopoietic progenitor cells with an antitat gene protects t-cell and macrophage progeny from aids virus infection. | transduction of hematopoietic stem cells with genes that inhibit human immunodeficiency virus (hiv) replication has the potential to reconstitute immune function in individuals with aids. we evaluated the ability of an autoregulated gene, antitat, to inhibit replication of simian immunodeficiency virus (siv) and hiv type 1 (hiv-1) in hematopoietic cells derived from transduced progenitor cells. the antitat gene expresses an antiviral rna encoding polymeric tat activation response elements in com ... | 1997 | 9060627 |
| replication-competent chimeric lenti-oncovirus with expanded host cell tropism. | baboon bone marrow was grafted into human immunodeficiency virus type 1-infected patients in the course of recent trials for aids treatment. since the baboon genome harbors multiple copies of an endogenous oncovirus, chimeric lenti-oncoviruses could emerge in the xenotransplant recipient. to analyze the potential replication competence of hybrid viruses between different genera of retroviruses, we replaced most of the env gene of simian immunodeficiency virus with the env gene of an amphotropic ... | 1997 | 9060704 |
| an hiv-1 infection-related idiotype/clonotype (1f7) is expressed on antibodies directed to envelope glycoprotein in simian immunodeficiency virus- and chimeric simian/human immunodeficiency virus-infected rhesus monkeys. | an antiidiotypic/clonotypic marker, designated 1f7, is restricted to antibodies directed to human immunodeficiency virus type 1 (hiv-1) envelope, core, and reverse transcriptase proteins. 1f7-id is shared by more than 70% of hiv-infected individuals, arising early and persisting throughout all disease stages. to study the specificity and biological function of this cross-reactive idiotypic marker, and to explore its potential in therapeutics, we have sought an appropriate animal model. 1f7-id+ a ... | 1997 | 9085123 |
| transmission and establishment of a persistent infection of enterocytozoon bieneusi, derived from a human with aids, in simian immunodeficiency virus-infected rhesus monkeys. | enterocytozoon bieneusi is closely linked with chronic diarrhea and wasting in aids. although reported >10 years ago, little is known about the infection and the disease it induces in humans. duodenal e. bieneusi spores from an aids patient were orally transmitted to 2 simian immunodeficiency virus-infected rhesus monkeys. both animals began shedding spores within a week of inoculation, as confirmed by microscopy and polymerase chain reaction, and continued until euthanatized 7 and 8 months late ... | 1997 | 9086173 |
| the nef gene products of both simian and human immunodeficiency viruses enhance virus infectivity and are functionally interchangeable. | adult rhesus macaques infected with nef-defective simian immunodeficiency virus (siv) exhibit extremely low levels of steady-state virus replication, do not succumb to immunodeficiency disease, and are protected from experimental challenge with pathogenic isolates of siv. similarly, rare humans found to be infected with nef-defective human immunodeficiency virus type 1 (hiv-1) variants display exceptionally low viral burdens and do not show evidence of disease progression after many years of inf ... | 1997 | 9094638 |
| identification of an enterocytozoon bieneusi-like microsporidian parasite in simian-immunodeficiency-virus-inoculated macaques with hepatobiliary disease. | enterocytozoon bieneusi is a common opportunistic pathogen of human patients with acquired immune deficiency syndrome (aids) causing significant morbidity and mortality. in a retrospective analysis utilizing conventional histochemical techniques, in situ hybridization, polymerase chain reaction, and ultrastructural examination, we identified 18 simian-immunodeficiency-virus-infected macaques (16 macaca mulatta, 1 m. nemestrina, and 1 m. cyclopis) with enterocytozoon infection of the hepatobiliar ... | 1997 | 9094995 |
| early treatment with 9-(2-phosphonylmethoxyethyl)adenine reduces virus burdens for a prolonged period in siv-infected rhesus macaques. | we evaluated the effects of a reverse transcriptase inhibitor, 9-(2-phosphonylmethoxyethyl)adenine (pmea), on simian immunodeficiency virus (siv) infection in rhesus macaques (macaca mulatta). four macaques were given pmea (20 mg/kg) subcutaneously on days 1 and 2 and inoculated with virus on day 2. drug treatment was continued for 30 consecutive days, after which the virus burdens and course of infection were monitored for a further 6 months. four control animals that did not receive pmea all d ... | 1997 | 9115811 |
| live attenuated siv vaccines are not effective in a postexposure vaccination model. | live attenuated simian immunodeficiency virus (siv) vaccines, like nef deletion mutants, have been the most effective vaccines tested in the siv/macaque model so far. the efficacy of live attenuated siv vaccines in therapeutic vaccination and postexposure prophylaxis has not been determined. inoculation of macaques with a pathogenic challenge virus and an attenuated siv vaccine at the same time mimics postexposure vaccination, whereby vaccination with the attenuated virus is performed as rapidly ... | 1997 | 9135877 |
| oral immunization with simian immunodeficiency virus p55gag and cholera toxin elicits both mucosal iga and systemic igg immune responses in nonhuman primates. | rhesus macaques were orally immunized with a mucosal vaccine consisting of two different concentrations (1 mg vs 250 microg) of recombinant siv p55gag (p55) with or without cholera toxin (ct, 50 microg) as a mucosal adjuvant. the plasma from macaques receiving the higher dose of p55 (1 mg) and ct had higher p55-specific igg and iga ab titers compared with macaques that received the lower dose of p55 (250 microg) and ct. further, high levels of p55-specific igg and iga abs were present in externa ... | 1997 | 9164952 |
| synergistic neutralization of a chimeric siv/hiv type 1 virus with combinations of human anti-hiv type 1 envelope monoclonal antibodies or hyperimmune globulins. | a panel of 14 human igg monoclonal antibodies (mabs) specific for envelope antigens of the human immunodeficiency virus type 1 (hiv-1), 2 high-titer human anti-hiv-1 immunoglobulin (hivig) preparations, and 15 combinations of mabs or mab/hivig were tested for their ability to neutralize infection of cultured human t cells (mt-2) with a chimeric simian immunodeficiency virus (shiv-vpu+), which expressed hiv-1 iiib envelope antigens. eleven mabs and both hivigs were neutralizing. when used alone, ... | 1997 | 9168233 |
| evolution of envelope-specific antibody responses in monkeys experimentally infected or immunized with simian immunodeficiency virus and its association with the development of protective immunity. | previous studies of attenuated simian immunodeficiency virus (siv) vaccines in rhesus macaques have demonstrated the development of broad protection against experimental challenge, indicating the potential for the production of highly effective immune responses to siv antigens. however, the development of this protective immune status was found to be critically dependent on the length of time postvaccination with the attenuated virus strain, suggesting a necessary maturation of immune responses. ... | 1997 | 9188572 |
| impaired mitogen-driven proliferation and cytokine transcription of lymphocytes from macaques early after simian immunodeficiency virus (siv) infection. | altered cytokine transcription might play an important role in the pathogenesis of human immunodeficiency virus (hiv) infection in humans. the infection of rhesus macaques with simian immunodeficiency virus (siv) provides a relevant animal model for hiv infection. therefore, we evaluated the cyokine transcription of phytohemagglutinin (pha)-stimulated lymphocytes in the early phase after infection of four rhesus macaques with pathogenic siv-mac239. to determine transcription of interleukin (il)- ... | 1997 | 9210280 |
| texture analysis of cerebral white matter in siv-infected macaque monkeys. | image texture analysis is used in a wide variety of applications in medical research. neurovirulent simian immunodeficiency virus (siv) infection in monkeys is considered a good model for hiv-1 infection in humans and causes neuropathological changes in white matter which can include diffuse myelin pallor, subtle white matter astrocytosis, perivascular macrophage infiltrates, and microglial nodules with multinucleated giant cells. the ability of image texture analysis to quantify these changes w ... | 1997 | 9210575 |
| simian immunodeficiency viruses containing mutations in the long terminal repeat nf-kappa b or sp1 binding sites replicate efficiently in t cells and pha-stimulated pbmcs. | the long terminal repeats (ltrs) of primate lentiviruses contain conserved binding sites for the nf-kappa b and sp1 cellular transcription factors. in order to study the role that these sites play in simian immunodeficiency virus (siv) replication, we have introduced mutations that disrupt either the nf-kappa b or sp1 binding sites in the ltr of an infectious molecular clone of sivmac239. an additional mutation also disrupted the sf3 transcription factor binding site that overlaps the nf-kappa b ... | 1997 | 9213395 |
| siv/hiv-1 hybrid virus expressing the reverse transcriptase gene of hiv-1 remains sensitive to hiv-1-specific reverse transcriptase inhibitors after passage in rhesus macaques. | we have previously described an animal model for the therapy of human immunodeficiency virus type 1 (hiv-1) infection with hiv-1-specific reverse transcriptase (rt) inhibitors based on a simian immunodeficiency virus (siv), in which the rt gene of siv was replaced by the rt gene of hiv-1. in vitro, replication of the hybrid virus, rt-shiv, was delayed compared with parental siv. rt-shiv could induce aids-like symptoms and pathologic alterations in rhesus macaques. characterization of re-isolates ... | 1997 | 9215647 |
| cytomegalovirus and simian immunodeficiency virus coinfection: longitudinal study of antibody responses and disease progression. | antibody titers to rhesus cytomegalovirus (rhcmv) were prospectively analyzed over a period of 68 weeks in a longitudinal serosurvey of 17 rhcmv-seropositive rhesus macaques (macaca mulatta) experimentally coinfected with simian immunodeficiency virus (siv). these were compared with anti-rhcmv titers in 18 animals that were also naturally infected with rhcmv but not infected with siv. fluctuations in anti-rhcmv antibody titers were observed within 5 weeks of siv inoculation, and two distinct pat ... | 1997 | 9215648 |
| 1h magnetic resonance spectroscopy reveals neuronal injury in a simian immunodeficiency virus macaque model. | infection with human immunodeficiency virus (hiv) commonly results in neurologic disease called the aids dementia complex. neuronal loss and injury have been found in the hiv brain, but the underlying mechanisms are not understood. the simian immunodeficiency virus (siv)-infected macaque is an excellent animal model for hiv infection, but neuronal loss has not been demonstrated. to determine whether neuronal damage occurs in the siv brain, we quantified the neuronal marker n-acetylaspartate (naa ... | 1997 | 9215650 |
| a humanized form of a cd4-specific monoclonal antibody exhibits decreased antigenicity and prolonged plasma half-life in rhesus monkeys while retaining its unique biological and antiviral properties. | certain monoclonal antibodies (mabs) directed against cd4 can efficiently block hiv-1 replication in vitro. to explore cd4-directed passive immunotherapy for prevention or treatment of aids virus infection, we previously examined the biological activity of a nondepleting cd4-specific murine mab, mu5a8. this mab, specific for domain 2 of cd4, blocks hiv-1 replication at a post-gp120-cd4 binding step. when administered to normal rhesus monkeys, all cd4+ target cells were coated with antibody, yet ... | 1997 | 9223409 |
| a role for natural simian immunodeficiency virus and human immunodeficiency virus type 1 nef alleles in lymphocyte activation. | a t-lymphoid cell line termed 221 was derived from a rhesus monkey infected with herpesvirus saimiri. growth of 221 cells was dependent on the addition of interleukin-2 (il-2) to the culture medium. in the absence of il-2, 221 cells arrested in g0-g1 but did not die. simian immunodeficiency virus (siv) replicated efficiently in il-2-stimulated 221 cells whether or not the nef gene was present. in the absence of il-2, nef-containing siv replicated 8 to 100 times more efficiently in 221 cells than ... | 1997 | 9223503 |
| characteristics of the cd8+ lymphocytosis during primary simian immunodeficiency virus infections. | to investigate the source of the expanded blood cd8+ subsets during an acute primary simian immunodeficiency virus (siv) infection of macaques and the potential role of these cells in disease progression. | 1997 | 9223729 |
| identification of mhc-mamu-dqb1 allele combinations associated with rapid disease progression in rhesus macaques infected with simian immunodeficiency virus. | 1997 | 9233476 | |
| two orphan seven-transmembrane segment receptors which are expressed in cd4-positive cells support simian immunodeficiency virus infection. | clinical isolates of primate immunodeficiency viruses, including human immunodeficiency virus type 1 (hiv-1), enter target cells by sequential binding to cd4 and the chemokine receptor ccr5, a member of the seven-transmembrane receptor family. hiv-1 variants which use additional chemokine receptors are present in the central nervous system or emerge during the course of infection. simian immunodeficiency viruses (siv) have been shown to use ccr5 as a coreceptor, but no other receptors for these ... | 1997 | 9236192 |
| cyclosporin a modulation of early virologic and immunologic events during primary simian immunodeficiency virus infection in rhesus monkeys. | virologic and immunologic effects of immunomodulation during primary simian immunodeficiency virus (siv) infection were examined in monkeys treated with cyclosporin or vehicle for 32 days beginning 5 days before siv inoculation. duration of antigenemia decreased in 5 of 7 treated monkeys, 2 having delayed onset and peak of antigenemia. although proviral dna levels in blood and lymph nodes and infected cell numbers in lymph nodes were transiently decreased, levels were similar to those in control ... | 1997 | 9237702 |
| association of simian immunodeficiency virus nef with cellular serine/threonine kinases is dispensable for the development of aids in rhesus macaques. | the nef gene of simian immunodeficiency virus (siv) is essential for high viral load and induction of aids in rhesus monkeys. a mutant form of the sivmac239 nef, which contains changes in a putative sh3-binding domain (amino acids 104 and 107 have been changed from pxxp to axxa), does not associate with cellular serine/threonine kinases, but is fully active in cd4 downregulation and associates with the cellular tyrosine kinase src. infection of two rhesus macaques with sivmac239 containing the m ... | 1997 | 9256276 |
| siv/deltab670 transmission across oral, colonic, and vaginal mucosae in the macaque. | the primary mode of human immunodeficiency virus (hiv) transmission worldwide is by exposure to the virus at vaginal, rectal, and oral mucosal surfaces. to understand hiv/simian immunodeficiency virus (siv) transmission events at mucosal portals of entry, we used the siv-macaque model to determine if mucosal surfaces function as barriers and select for particular viral genotypes. rhesus macaques were inoculated intravaginally, intracolonically, intrarectally, or orally with the complex primary v ... | 1997 | 9271183 |
| immunization of macaca mulatta with aroa attenuated salmonella typhimurium expressing the sivp27 antigen. | attenuated bacteria expressing foreign antigens stimulate both systemic and mucosal immune responses to the recombinant protein. we studied the infection of rhesus macaques with an attenuated salmonella typhimurium expressing the simian immunodeficiency virus p27 capsid protein. juvenile rhesus macaques were inoculated by intragastric intubation with doses ranging from 3 to 9 x 10(9) viable aroa attenuated s. typhimurium. the bacterial infection was self-limiting with no overt clinical signs. sa ... | 1997 | 9271188 |
| a model for the maturation of protective antibody responses to siv envelope proteins in experimentally immunized monkeys. | studies using live attenuated virus vaccines in the simian immunodeficiency virus (siv) rhesus macaque model have demonstrated broad protection against experimental challenge. protection in these studies was found to be critically dependent on the length of time postvaccination, suggesting that protective immunity involves a necessary maturation of immune responses. the current study characterizes the evolution of protective envelope-specific antibody responses from monkeys inoculated with the h ... | 1997 | 9271189 |
| neutralization sensitivity of cell culture-passaged simian immunodeficiency virus. | cemx174- and c8166-45-based cell lines which contain a secreted alkaline phosphatase (seap) reporter gene under the control of a tat-responsive promoter derived from either sivmac239 or hiv-1(nl4-3) were constructed. basal levels of seap activity from these cell lines were low but were greatly stimulated upon transfection of tat expression plasmids. infection of these cell lines with simian immunodeficiency virus (siv) or human immunodeficiency virus type 1 (hiv-1) resulted in a dramatic increas ... | 1997 | 9311879 |
| gene gun-based nucleic acid immunization alone or in combination with recombinant vaccinia vectors suppresses virus burden in rhesus macaques challenged with a heterologous siv. | gene gun-based dna immunization alone or in combination with recombinant vaccinia vectors was evaluated for the ability to elicit protective immune responses in rhesus macaques challenged with a pathogenic, heterologous simian immunodeficiency virus (siv). six monkeys primed with seven consecutive doses of dna encoding sivmac239 gp120 and gp160 (dna + dna) were divided into two groups. three of these animals received another dna booster immunization and the remaining three received a booster imm ... | 1997 | 9315483 |
| live, attenuated simian immunodeficiency virus vaccines elicit potent resistance against a challenge with a human immunodeficiency virus type 1 chimeric virus. | three rhesus macaques, previously immunized with sivdelta3 or sivdelta2, each an attenuated derivative of sivmac239, and two naive monkeys were challenged with 30,000 50% tissue culture infective doses of shiv, an siv/human immunodeficiency virus type 1 (hiv-1) chimeric virus bearing the dual-tropic envelope of hiv-1dh12. by several criteria, including virus isolation, serological assays, and pcr (both dna and reverse transcriptase), shiv levels were reduced to barely detectable levels in the ci ... | 1997 | 9343164 |
| an adenovirus-simian immunodeficiency virus env vaccine elicits humoral, cellular, and mucosal immune responses in rhesus macaques and decreases viral burden following vaginal challenge. | six female rhesus macaques were immunized orally and intranasally at 0 weeks and intratracheally at 12 weeks with an adenovirus type 5 host range mutant (ad5hr)-simian immunodeficiency virus sivsm env recombinant and at 24 and 36 weeks with native sivmac251 gp120 in syntex adjuvant. four macaques received the ad5hr vector and adjuvant alone; two additional controls were naive. in vivo replication of the ad5hr wild-type and recombinant vectors occurred with detection of ad5 dna in stool samples a ... | 1997 | 9343211 |
| immunoglobulin v(h) usage during primary infection of rhesus monkeys with chimeric simian-human immunodeficiency viruses. | it has been suggested that naive immunoglobulins encoded by the v(h)3 gene family interact aberrantly with human immunodeficiency virus type 1 (hiv-1) gp120 via a superantigenic epitope, causing initial expansion and eventual depletion of v(h)3-expressing b cells. however, this possibility has not been prospectively assessed during an aids virus infection. we determined v(h) family usage in rhesus monkeys during primary infection with chimeric viruses expressing hiv-1 envelopes on a simian immun ... | 1997 | 9343216 |
| no reactivation of attenuated immunodeficiency viruses in rhesus macaques after vaccinia virus-induced immune activation. | live-attenuated simian immunodeficiency virus (siv) protects macaques against challenge with pathogenic siv. to evaluate the safety of such vaccines, an investigation of whether or not nef-deleted siv could be reactivated in vivo by immune activation of the host was conducted. in addition, monkeys infected with apathogenic siv/hiv-1 chimeric viruses, and two control monkeys that had suppressed replication of pathogenic siv were examined. during the infection virus became undetectable or persiste ... | 1997 | 9349473 |
| correlation of major histocompatibility complex with opportunistic infections in simian immunodeficiency virus-infected rhesus monkeys. | the role of the major histocompatibility complex (mhc) in the pathogenesis of aids is complex because of compounding variables within the virus, host, and environment. important variables can be controlled by using the experimental animal model of aids induced by simian immunodeficiency virus in rhesus monkeys (macaca mulatta). we studied whether the mhc type influenced which opportunistic infections arose in an individual monkey. several associations were found. for example, cytomegalovirus was ... | 1997 | 9354765 |
| simian immunodeficiency virus burden in tissues and cellular compartments during clinical latency and aids. | in the course of human immunodeficiency virus infection or of the related simian immunodeficiency virus (siv), progression to aids is associated with high virus burdens in blood. how virus burden in the bloodstream is related to virus burden in tissue reservoirs was addressed in an animal model of rhesus macaques infected with siv. in situ hybridization and quantitative image analysis were used to quantitate virus burden. animals who developed aids had high levels of virus production and storage ... | 1997 | 9359719 |
| simian immunodeficiency virus: a model for neuroaids. | in addition to its profound effects on the immune system, hiv also infects the cns and can cause abnormalities in infected individuals ranging from mild cognitive and motor disorders to frank dementia. we have been actively investigating the molecular and cellular mechanisms underlying the cns manifestations of lentivirus infection through the comparative evaluation of brain pathophysiology under a number of parallel interrelated strategies. here we describe our ongoing studies with the siv/rhes ... | 1997 | 9361303 |
| effects of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg) in surface lymph nodes of rhesus monkeys (macaca mulatta) chronically infected with simian immunodeficiency virus (sivmac239). | we studied the effects of 6-chloro-2',3'-dideoxyguanosine (6-cl-ddg), an antiretroviral drug, in surface lymph nodes of rhesus monkeys (macaca mulatta) chronically infected with simian immunodeficiency virus (siv). the rhesus monkeys were treated with 25 mg/kg of 6-cl-ddg every 8 hr for 2 weeks. we performed sequential biopsies of the surface lymph nodes three times: before, during, and after the drug treatment. the 6-cl-ddg dramatically decreased the number of infectious virus (measured by limi ... | 1997 | 9362037 |
| a recombinant prime, peptide boost vaccination strategy can focus the immune response on to more than one epitope even though these may not be immunodominant in the complex immunogen. | rhesus monkeys were successfully vaccinated using a strategy of priming with a candidate envelope subunit vaccine and boosting with synthetic peptides. priming was carried out with recombinant hiv-1 sf2 envelope glycoprotein incorporated into iscoms, following the attachment of a lipid tail. peptides, covalently linked to iscoms, representing linear sequences with the v2 and v3 regions, were used to boost functional antibodies-to neutralizing epitopes in both of these regions. injections with th ... | 1997 | 9364697 |
| 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 |
| cd4-independent binding of siv gp120 to rhesus ccr5. | ccr5 and cd4 are coreceptors for immunodeficiency virus entry into target cells. the gp120 envelope glycoprotein from human immunodeficiency virus strain hiv-1(yu2) bound human ccr5 (ccr5hu) or rhesus macaque ccr5 (ccr5rh) only in the presence of cd4. the gp120 from simian immunodeficiency virus strain sivmac239 bound ccr5rh without cd4, but ccr5hu remained cd4-dependent. the cd4-independent binding of sivmac239 gp120 depended on a single amino acid, asp13, in the ccr5rh amino-terminus. thus, cc ... | 1997 | 9367961 |
| identification of the v1 region as a linear neutralizing epitope of the simian immunodeficiency virus sivmac envelope glycoprotein. | the sequence variability of viral structure polypeptides has been associated with immune escape mechanisms. the v1 region of simian immunodeficiency virus (siv) is a highly variable region of the sivmac env gene. here, we describe the v1 region as a linear neutralizing epitope. v1 region-specific neutralizing antibodies (nab) were first demonstrated in a rabbit infected with a recombinant vaccinia virus carrying the env gene of human immunodeficiency virus type 2 strain ben (hiv-2ben). since we ... | 1997 | 9371609 |
| direct demonstration of retroviral recombination in a rhesus monkey. | recombination may be an important mechanism for increasing variation in retroviral populations. retroviral recombination has been demonstrated in tissue culture systems by artificially creating doubly infected cells. evidence for retroviral recombination in vivo is indirect and is based principally on the identification of apparently mosaic human immunodeficiency virus type 1 genomes from phylogenetic analyses of viral sequences. we infected a rhesus monkey with two different molecularly cloned ... | 1997 | 9371629 |
| transfer of the hiv-1 cyclophilin-binding site to simian immunodeficiency virus from macaca mulatta can confer both cyclosporin sensitivity and cyclosporin dependence. | hiv-1 specifically incorporates the peptidyl prolyl isomerase cyclophilin a (cypa), the cytosolic receptor for the immunosuppressant cyclosporin a (csa). hiv-1 replication is inhibited by csa as well as by nonimmunosuppressive csa analogues that bind to cypa and interfere with its virion association. in contrast, the related simian immunodeficiency virus sivmac, which does not interact with cypa, is resistant to these compounds. the incorporation of cypa into hiv-1 virions is mediated by a speci ... | 1997 | 9380739 |
| [contribution of animal models in the understanding of aids encephalopathy]. | the neuropathology associated with hiv (human immunodeficiency virus) infection is one of the major complications of this disease. the virological and cellular mechanisms by which hiv infection induces motor and cognitive disorders remain unknown. this lack of understanding of the pathophysiology is partly due to the difficulty of experimental analysis in man because only post-mortem samples from terminal phases of the disease and cerebrospinal fluid samples are available. two animal models, ver ... | 1997 | 9382613 |
| intracellular immunization of rhesus cd34+ hematopoietic progenitor cells with a hairpin ribozyme protects t cells and macrophages from simian immunodeficiency virus infection. | evaluation of candidate genes for stem cell gene therapy for acquired immunodeficiency syndrome (aids) has been limited by the difficulty of supporting in vitro t-cell differentiation of genetically modified hematopoietic progenitor cells. using a novel thymic stromal culture technique, we evaluated the ability of a hairpin ribozyme specific for simian immunodeficiency virus (siv) and human immunodeficiency virus type 2 (hiv-2) to inhibit viral replication in t lymphocytes derived from transduce ... | 1997 | 9389699 |
| intestinal manifestations of experimental siv-infection in rhesus monkeys (macaca mulatta): a histological and ultrastructural study. | intestinal lesions were studied in 32 rhesus monkeys experimentally infected with different strains of simian immunodeficiency virus sivmac (251/32h, 251/32h-spl and 251/mpbl) by light microscopy, transmission and scanning electron microscopy. a spectrum of primary and secondary manifestations of siv-infection were detected. primary changes included 'siv-enteropathy' in 12 monkeys and virus-induced syncytial giant cell formation (gcf) of the intestine in two animals. a primary virus-induced ente ... | 1997 | 9394615 |
| cd4-independent, ccr5-dependent infection of brain capillary endothelial cells by a neurovirulent simian immunodeficiency virus strain. | brain capillary endothelial cells (bcecs) are targets of cd4-independent infection by hiv-1 and simian immunodeficiency virus (siv) strains in vitro and in vivo. infection of bcecs may provide a portal of entry for the virus into the central nervous system and could disrupt blood-brain barrier function, contributing to the development of aids dementia. we found that rhesus macaque bcecs express chemokine receptors involved in hiv and siv entry including ccr5, ccr3, cxcr4, and strl33, but not ccr ... | 1997 | 9405683 |
| the liver in aids. | deficits in cell-mediated immunity in aids result in a wide variety of hepatic complications, including granulomas, cytomegalovirus hepatitis, multimicrobial aids cholangiopathy, kaposi's sarcoma, and lymphoma. kupffer cells are the major hepatic target cell population for human immunodeficiency virus-1 (hiv-1), and rhesus monkeys with simian immunodeficiency virus infection have served as a model for ultrastructural analysis of viral clearance by these cells. the majority of patients with estab ... | 1997 | 9408969 |
| infection of macaque monkeys with simian immunodeficiency virus: an animal model for neuro-aids. | due to the worldwide aids pandemic, hiv-1 has become the major factor for central nervous system (cns) diseases. two major disorders of the cns caused by hiv-1 have been described, a meningoencephalitis which occurs in 30-50% of patients early after infection and the aids dementia complex (adc, also known as hiv-associated dementia) which is characterized by a predominantly subcortical dementia. the pathophysiology of these clinical syndromes still remains an enigma. however, since monocytes/mac ... | 1997 | 9450228 |
| siv infection of macaques: a model for studying aids and drug abuse. | rhesus monkeys (macaca mulatta) and the simian immunodeficiency virus (siv) were used as an animal model system to evaluate longitudinally the effects of opioid dependence on the development of aids. results have shown that in addition to weakening the host's t cell and pmn functions, chronic opioid treatment of sivmac239-infected animals caused (a) an increased virus replication rate, (b) an increased rate of viral mutation, (c) a nascent humoral (antibody) response against mutated autologous s ... | 1997 | 26735947 |
| the rhesus macaque ccr3 chemokine receptor is a cell entry cofactor for hiv-2, but not for hiv-1. | the eotaxin receptor (ccr3) is a cd4-associated coreceptor for human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2). by comparison with other chemokine receptors, such as ccr5 and cxcr4, the primary sequences of human ccr3 and its rhesus macaque homolog were markedly different in their extracellular domains. human cd4+ cells expressing ccr3 from either human or macaque origin could be infected by hiv-2, with apparently similar efficiency, but only cells expressing human ccr3 could be i ... | 1998 | 9454694 |
| targeted lymph-node immunization with whole inactivated simian immunodeficiency virus (siv) or envelope and core subunit antigen vaccines does not reliably protect rhesus macaques from vaginal challenge with sivmac251. | sexual transmission of hiv is the most common route of hiv transmission throughout the world. to prevent sexually transmitted hiv infection, a vaccine is urgently needed. a previous report demonstrated the targeted immunization of the iliac lymph nodes with simian immunodeficiency virus (siv) subunits protects rhesus macaques from rectal challenge with siv. we sought to determine whether this immunization strategy could protect rhesus macaques from vaginal challenge with siv. | 1998 | 9456249 |
| reduction in siv replication in rhesus macaques infused with autologous lymphocytes engineered with antiviral genes. | simian immunodeficiency virus (siv) infection of nonhuman primates is one of the most relevant animals models of hiv infection in humans. to test a potential anti-hiv gene therapy strategy in this model, cd4-enriched lymphocytes from three rhesus macaques were subjected to retrovirally mediated gene transfer with a vector expressing an antisense tat/rev gene. this group of animals and three control macaques were subsequently infected with sivmac239. blood and lymph nodes from all macaques were s ... | 1998 | 9461191 |