| early events in lymph nodes during infection with siv and fiv. | to elucidate the initial pathogenic events in lymphoid organs, the major reservoir of virus in hiv infection, follow-ups of viral load, pathological changes and target cells were performed in the rhesus macaque sivmac251 model and in the cat fiv model. lymph nodes (ln) obtained from animals sacrificed at early time points following experimental inoculation were analysed by in situ hybridization for virus load and by combined immunohistochemistry and in situ hybridization for virus cellular tropi ... | 1994 | 7800949 |
| signs of kupffer cell involvement in productive simian immunodeficiency virus infection in monkey liver. | the livers of 21 rhesus monkeys inoculated with sivmac251 were examined at 4 days to 39 months after infection. siv antigens were detected in the cytoplasm of kupffer cells (kc), macrophages and lymphocytes in two-thirds of the livers tested. the number of cells containing viral proteins substantially increased during the development of the disease, and kc were the main cell type displaying siv proteins at an advanced stage of infection. mature and immature lentiviral particles were found in cyt ... | 1994 | 7800950 |
| detection of siv in rhesus monkey thymus stroma cell cultures. | to clarify the pathogenesis of siv-induced thymus atrophy, the presence of siv within thymus stromal cell cultures (epithelial cells, idc, macrophages or fibroblasts) was investigated. the material studied consisted of 15 thymus specimens of rhesus macaques infected with sivmac251 (2-4 months postinoculation). no viral antigen was detected, either in the cultures, by immunohistochemistry, or in cell culture supernatants, by elisa (p17 antigen), and no viral rna was detected by in situ hybridizat ... | 1994 | 7800951 |
| development of malabsorption and nutritional complications in simian immunodeficiency virus-infected rhesus macaques. | to assess the development and cause of malabsorption in rhesus macaques following experimental simian immunodeficiency virus (siv) infection and to evaluate its impact on nutritional status. | 1994 | 7802976 |
| persistent infection with sivmac chimeric virus having tat, rev, vpu, env and nef of hiv type 1 in macaque monkeys. | a chimeric human and simian immunodeficiency virus carrying the tat, rev, vpu, env, and nef genes of human immunodeficiency virus type 1 was generated. the chimeric virus, nm-3n, grew competently in peripheral blood mononuclear cells from cynomolgus monkeys like the parental sivmac. two cynomolgus monkeys and one rhesus monkey inoculated with nm-3n raised antibodies to sivmac gag and hiv-1 env. the antibodies raised in the cynomolgus monkeys persisted for at least 1.7 years. the antibodies conta ... | 1994 | 7811533 |
| extracellular vpr protein increases cellular permissiveness to human immunodeficiency virus replication and reactivates virus from latency. | the vpr gene product of human immunodeficiency virus (hiv) and simian immunodeficiency virus is a virion-associated regulatory protein that has been shown using vpr mutant viruses to increase virus replication, particularly in monocytes/macrophages. we have previously shown that vpr can directly inhibit cell proliferation and induce cell differentiation, events linked to the control of hiv replication, and also that the replication of a vpr mutant but not that of wild-type hiv type 1 (hiv-1) was ... | 1995 | 7815499 |
| regions required for cd4 binding in the external glycoprotein gp120 of simian immunodeficiency virus. | the external domain of the envelope glycoprotein, gp120, of simian immunodeficiency virus (siv) has been expressed as a mature secreted product using recombinant baculoviruses and the expressed protein, which has an observed molecular mass of 110 kda, was purified by monoclonal antibody (mab) affinity chromatography. n-terminal sequence analysis showed a signal sequence cleavage identity similar to that of the gp120s of both human immunodeficiency virus type 1 (hiv-1) and hiv type 2. the express ... | 1995 | 7815501 |
| simian immunodeficiency virus sivmac chimeric virus whose env gene was derived from siv-encephalitic brain is macrophage-tropic but not neurovirulent. | we inoculated four rhesus macaques with molecularly cloned simian immunodeficiency virus sivmac239/17e env, a chimeric virus whose env gene was derived from the brain of an siv-encephalitic macaque. blood and lymphoid tissues had high frequencies of infected cells. the virus was neuroinvasive, but productive virus replication did not occur in the brain, and animals did not develop encephalitis. | 1995 | 7815523 |
| induction of aids by simian immunodeficiency virus from an african green monkey: species-specific variation in pathogenicity correlates with the extent of in vivo replication. | previous studies suggested that simian immunodeficiency viruses isolated from african green monkeys (sivagm) are relatively nonpathogenic. the report describes the isolation and biologic and molecular characterization of a pathogenic sivagm strain derived from a naturally infected african green monkey. this virus induced an aids-like syndrome characterized by early viremia, frequent thrombocytopenia, severe lymphoid depletion, opportunistic infections, meningoencephalitis, and death of five of e ... | 1995 | 7815563 |
| t-cell proliferation to subinfectious siv correlates with lack of infection after challenge of macaques. | to analyze correlates of protection in macaques exposed to siv. | 1994 | 7818809 |
| induction of resistance to 1-beta-d-arabinofuranosylcytosine in human h9 cell line by simian immunodeficiency virus. | we examined drug sensitivity of human t cell acute lymphoblastic leukemia h9 cells chronically infected with simian immunodeficiency virus (sivmac) and found that the retrovirus-infected h9 cells showed 8.2-fold resistance to 1-beta-d-arabinofuranosylcytosine (ara-c). in the infected cells, ara-ctp levels decreased to 20% of that found in uninfected h9 cells after 3 h incubation at ara-c concentration of 1 microm, and 8.1-fold increase of cytidine deaminase activity was observed in the infected ... | 1995 | 7826366 |
| phylogenesis and genetic complexity of the nonhuman primate retroviridae. | the three known groups of nonhuman primate retroviruses (simian immunodeficiency virus, simian t cell lymphotropic/leukemic virus type i, and simian foamy virus) are thought to have equivalent human counterparts. this is clearly the case with human immunodeficiency virus types 1 and 2, the causative agents of acquired immunodeficiency syndrome, and with human t cell lymphotropic/leukemia virus type i (htlv-i), which causes t cell leukemia and a progressive form of myelopathy (tropical spastic pa ... | 1994 | 7826692 |
| the proteins of lymphocyte- and macrophage-tropic strains of simian immunodeficiency virus are processed differently in macrophages. | since the pathogenesis of sivmac disease complex is thought to be explained by the tropism of the infecting virus for either cd4+ t-lymphocytes or macrophages or both types of cells, we compared the infection in primary macaque macrophages with molecularly cloned, lymphocyte-tropic sivmac239 and a cloned, macrophage-tropic chimeric virus (sivmac239/17e) whose env gene was derived from brain of a macaque (17e) dying from siv-induced encephalopathy. sivmac239/17e caused a productive, syncytial cyt ... | 1995 | 7831808 |
| antibodies to human and non-human primate cellular and culture medium components in macaques vaccinated with the simian immunodeficiency virus. | inactivated simian immunodeficiency virus (siv) grown in a human t-cell line induces protection from infection by the virus in macaques. however, observations that immunization with uninfected human t cells or with siv-1 prepared in human t cells can also induce protection, has raised the possibility that protective antigens could be of human cellular origin. sera from animals immunized with fixed infected and uninfected human t cells, as well as from animals immunized with partially purified ce ... | 1994 | 7835937 |
| comparison of rates of intracellular metabolism of zidovudine in human and primate peripheral blood mononuclear cells. | 3'-azido-3'-deoxythymidine (azt) is a drug of choice for the treatment of aids. on the basis of pharmacokinetic data, the nonhuman primate macaca nemestrina has been shown to be a suitable animal model for use in the study of the disposition of azt. however, since azt is activated to its metabolite, the azt triphosphate (azttp), intracellularly, we investigated the intracellular activation of azt in peripheral blood mononuclear cells (pbmcs) of healthy and simian immunodeficiency virus-infected ... | 1994 | 7840577 |
| viral dna burden and decline in percentage of cd4-positive cells in the lymphoid compartment of siv-infected macaques. | the decline in cd4+ cells and increased viral dna and rna burden in the blood of human immunodeficiency virus (hiv)-infected individuals have been used as closely related correlates of disease progression. however, little is known about levels of total or unintegrated viral dna in lymphoid tissue of hiv-infected patients and how they relate to cd4+ cell decline or disease progression. exploiting the similarities between hiv- and simian immunodeficiency virus (siv)-induced disease, we examined ly ... | 1994 | 7848682 |
| an animal model for antilentiviral therapy: effect of zidovudine on viral load during acute infection after exposure of macaques to simian immunodeficiency virus. | we analyzed the kinetics of the virological and immunological events that occurred in four azt-treated cynomolgus macaques during the acute infection that followed their exposure to the simian immunodeficiency virus (sivmac251) grown on monkey pbmcs in a cell-free stock solution. these events included changes in the cd4+ and cd8+ t lymphocyte subsets, p27 antigenemia, infectious serum virus, and cell-associated virus loads. the kinetics of these changes proved strikingly similar to those reporte ... | 1994 | 7848683 |
| isolation of simian immunodeficiency viruses from two sooty mangabeys in côte d'ivoire: virological and genetic characterization and relationship to other hiv type 2 and sivsm/mac strains. | to search for the presence of siv in sooty mangabeys and other monkey species in côte d'ivoire, west africa, and to compare viral isolates with hiv-2 strains from the same region. | 1994 | 7848684 |
| fine analysis of humoral antibody response to envelope glycoprotein of siv in infected and vaccinated macaques. | to characterize the serological response to siv envelope, induced by vaccination with different envelope immunogens or by siv infection, plasma samples from 11 cynomolgus macaques infected with simian immunodeficiency virus (siv) and from 16 macaques vaccinated with three different recombinant envelope proteins were analyzed by (1) elisa, using a variety of antigens including overlapping peptides encompassing the entire sequence of the envelope protein of siv, and (2) competition assays, using n ... | 1994 | 7848685 |
| mechanisms of hiv/siv mucosal transmission. | the division of aids (daids), national institute of allergy and infectious diseases (niaid), organized a workshop on hiv/siv pathogenesis and mucosal transmission on march 14-17, 1994, attended by over 300 participants. the purpose of the workshop was to foster research in the areas of hiv pathogenesis, mucosal transmission, and host factors modulating hiv infection and disease. this article summarizes workshop presentations that focused on mechanisms of hiv or siv mucosal transmission. the foll ... | 1994 | 7848686 |
| ultrastructural correlation between follicular dendritic cells and the frequency of virus-like particles during the lymph nodes reaction of siv/hiv 2 infected cynomolgus monkeys. | lymph nodes from 18 siv/hiv2 infected monkeys developing a severe aids-like disease were studied by electron microscopy. the lesions were correlated with the histopathologic staining and the anti-sivp28 immunostaining. the investigation of follicular dendritic cells (fdc) and associated retroviral particles was focused on the light zones of germinal centres during the follicular hyperplasia, fragmentation atrophy and depletion. fdcs were mostly developed in the first two stages, while the highes ... | 1993 | 7849288 |
| reactivation of human immunodeficiency virus type 2 in macaques after simian immunodeficiency virus sivmac superinfection. | by superinfection of human immunodeficiency virus type 2 (hiv-2) strain hiv-2ben-infected macaques with simian immunodeficiency virus (siv) strain sivmac, we investigated the mutual influences of an apathogenic and a pathogenic virus in vivo. four rhesus and two cynomolgus monkeys were infected with hiv-2ben in 1988 and 1989, respectively. virus could be reisolated from five of six animals 6 weeks after infection. the monkeys remained healthy over the next 2 to 3 years. pcr for viral rna became ... | 1995 | 7853490 |
| the central globular domain of the nucleocapsid protein of human immunodeficiency virus type 1 is critical for virion structure and infectivity. | the nucleocapsid protein ncp7 of human immunodeficiency virus type 1 (hiv-1) is a 72-amino-acid peptide containing two cchc-type zinc fingers linked by a short basic sequence, 29raprkkg35, which is conserved in hiv-1 and simian immunodeficiency virus. the complete three-dimensional structure of ncp7 has been determined by 1h-nuclear magnetic resonance spectroscopy (n. morellet, h. de rocquigny, y. mely, n. jullian, h. demene, m. ottmann, d. gerard, j. l. darlix, m. c. fournié-zaluski, and b. p. ... | 1995 | 7853517 |
| proline-rich (pxxp) motifs in hiv-1 nef bind to sh3 domains of a subset of src kinases and are required for the enhanced growth of nef+ viruses but not for down-regulation of cd4. | human immunodeficiency virus (hiv) and simian immunodeficiency virus nef proteins contain a conserved motif with the minimal consensus (pxxp) site for src homology region 3 (sh3)-mediated protein-protein interactions. nef pxxp motifs show specific binding to biotinylated sh3 domains of hck and lyn, but not to those of other tested src family kinases or less related proteins. a unique cooperative role of a distant proline is also observed. endogenous hck of monocytic u937 cells can be specificall ... | 1995 | 7859737 |
| antibody to the human interferon-alpha receptor reduces the loss of cd4+ t cells in macaques infected with the simian immunodeficiency virus, sivmac. | | 1994 | 7861032 |
| vaccine protection and reduced virus load from heterologous macaque-propagated siv challenge. | the efficacy of vaccine protection afforded by live attenuated vaccines was tested by heterologous sivtno8980 challenge following successful protection against homologous sivmac32h challenge. animals immunized with the attenuated sivmacbk28 molecular clone were asymptomatic and virus isolation negative by quantitative virus isolation prior to challenge. two groups of four animals previously immunized 5 years and 4 months (respectively) were challenged with 100 mid50 of sivtno8980, as was a third ... | 1994 | 7865285 |
| effect of mutations in rev gene of sivmac on virus replication. | the functional activity of sivmac251 rev was altered by introducing amino acid changes inside and chain termination mutations after the rev response element-binding region (rbr) of the protein. the effects of specific mutations were evaluated by transfecting proviral dnas into the hela cell line and into hela cells constitutively expressing either hiv-1 rev or htlv-1 rex proteins. cell-free supernatants from these transient expression assays were further characterized by infecting cd4-positive l ... | 1994 | 7865286 |
| immunization with virion-derived glycoprotein 130 from hiv-2 or siv protects macaques against challenge virus grown in human or simian cells or prepared ex vivo. | we have compared in the macaque model the efficacy of the virion-derived glycoprotein of hiv-2ben (hiv-2 gp130) with that of sivmac251/32h (siv gp130). the latter vaccination trial was in part combined with vaccinia virus (vv) priming. both antigen preparations induced a strong humoral, but a weak cellular, immune response. the first challenge was performed with autologous virus grown on a human t cell line. more than 50% of the monkeys immunized with hiv-2 gp130 (five of nine) and 63% of the mo ... | 1994 | 7865316 |
| comparative functional analysis of the various lentivirus long terminal repeats in human colon carcinoma cell line (sw480 cells) and feline renal cell line (crfk cells). | basal promoter activities of various lentiviral long terminal repeats (ltrs) in a human colon carcinoma cell line (sw480 cells) and a feline renal cell line (crfk cells) were examined by the chloramphenicol acetyltransferase (cat) assay using the ltr-cat reporter plasmids. in sw480 cells, the basal promoter activities induced by ltrs of visna virus, caprine arthritis-encephalitis virus (caev), and simian immunodeficiency virus (sivagm) were moderate, and those induced by ltrs of human immunodefi ... | 1994 | 7865591 |
| early helper t-cell dysfunction in simian immunodeficiency virus but not in human immunodeficiency virus type-2-infected macaques. | both naive and vaccinated macaques acquired a virus-specific proliferative helper t-cell reactivity in response to infection with the nonpathogenic human immunodeficiency virus type 2 (hiv-2). in contrast, macaques infected with the pathogenic simian immunodeficiency virus of the macaque strain (sivmac) did not develop a helper t-cell response. furthermore, a vaccine-induced preexisting t-cell reactivity was abrogated after sivmac infection in vaccine failures. these differences may reflect the ... | 1994 | 7869358 |
| effects of chronic zidovudine administration on cns function and virus burden after perinatal siv infection in rhesus monkeys. | continuous intravenous administration of zidovudine (azt) has been reported to improve cognitive function in hiv-infected pediatric patients (pizzo et al., 1988). the effects of long-term zidovudine treatment in the perinatally infected pediatric population, including antiviral efficacy and effects on cognitive and motor function has not been systematically examined. these questions were addressed in rhesus macaque infants infected at birth with sivsmm/b670, a primate model for infantile hiv inf ... | 1994 | 7874391 |
| neuronal substrates for siv encephalopathy. | prior to the onset of immunodeficiency disease, neurochemical and neuropathological events associated with motor and/or cognitive impairment can be identified in rhesus monkeys infected with simian immunodeficiency virus (siv). these are astrocytosis, up-regulation of mrna encoding the neuropeptide somatostatin (srif) and an increased expression of mhc class ii antigen. end-stage immunodeficiency disease has been associated with robust viral expression in the cns frequently observed as multinucl ... | 1994 | 7874394 |
| 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 |
| an early increase in somatostatin mrna expression in the frontal cortex of rhesus monkeys infected with simian immunodeficiency virus. | motor and cognitive impairment is common in human immunodeficiency virus disease in humans and simian immunodeficiency virus (siv) disease in rhesus monkeys. we have examined peptide neurotransmitter expression in the frontal cortex of siv-infected rhesus monkeys to identify alterations in cortical neurons that might explain this impairment. a 2-fold higher number of preprosomatostatin (srif) mrna-positive interneurons was observed in layer iv of frontal cortex in two separate cohorts of siv-inf ... | 1995 | 7877985 |
| functional analysis of the vpx, vpr, and nef genes of simian immunodeficiency virus. | the role of the vpx, vpr, and nef genes in the replication of simian immunodeficiency virus (siv) was investigated using point and deletion mutations in these genes. the effects on replication kinetics of single or combined mutants--vpx, vpr, vpx-vpr, vpx-nef, vpr-nef, and vpx-vpr-nef--in established lymphoid cemx174 and mt-4 cells were negligible, except that the postinfection appearance of vpx-nef, vpr-nef, and vpx-vpr-nef progeny virus was slightly delayed in mt-4 cells. the vpx, but not the ... | 1995 | 7882097 |
| 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 |
| a vaccine-elicited, single viral epitope-specific cytotoxic t lymphocyte response does not protect against intravenous, cell-free simian immunodeficiency virus challenge. | protection against simian immunodeficiency virus (siv) challenge was assessed in rhesus monkeys with a vaccine-elicited, single siv epitope-specific cytotoxic t-lymphocyte (ctl) response in the absence of siv-specific antibody. strategies were first explored for eliciting an optimal siv gag epitope-specific ctl response. these studies were performed in rhesus monkeys expressing the major histocompatibility complex (mhc) class i gene mamu-a*01, a haplotype associated with a predominant siv ctl ep ... | 1995 | 7884874 |
| progression to aids in the absence of a gene for vpr or vpx. | rhesus monkeys (macaca mulatta) were experimentally infected with strains of simian immunodeficiency virus (siv) derived from sivmac239 lacking vpr, vpx, or both vpr and vpx genes. these auxiliary genes are not required for virus replication in cultured cells but are consistently conserved within the sivmac/human immunodeficiency virus type 2/sivsm group of primate lentiviruses. all four rhesus monkeys infected with the vpr deletion mutant showed an early spike in plasma antigenemia, maintained ... | 1995 | 7884883 |
| mode of action of sdz nim 811, a nonimmunosuppressive cyclosporin a analog with activity against human immunodeficiency virus (hiv) type 1: interference with hiv protein-cyclophilin a interactions. | cyclosporins, in particular the nonimmunosuppressive derivative sdz nim 811, exhibit potent anti-human immunodeficiency virus type 1 (hiv-1) activity in vitro. sdz nim 811 interferes at two stages of the viral replication cycle: (i) translocation of the preintegration complex to the nucleus and (ii) production of infectious virus particles. immunosuppressive activity is not correlated with anti-hiv-1 activity of cyclosporins. however, binding to cyclophilin a, the major cellular receptor protein ... | 1995 | 7884893 |
| chimeric macaque/human fab molecules neutralize simian immunodeficiency virus. | a collection of simian immunodeficiency virus (siv) neutralizing recombinant fab fragments was generated using the combinatorial antibody library approach. functional antibody fragments efficiently expressed in escherichia coli were identified only in the form of chimeric macaque heavy chain gamma 1 and human light chain kappa. the gamma 1 and kappa chains were derived from a clinically healthy long-term surviving sivsm-infected cynomolgus macaque and from an asymptomatic hiv-2 seropositive indi ... | 1995 | 7886953 |
| progression to aids in macaques is associated with changes in the replication, tropism, and cytopathic properties of the simian immunodeficiency virus variant population. | human immunodeficiency virus type 1 (hiv-1) typically evolves from a macrophage-tropic, noncytopathic virus at early asymptomatic stages of infection to a t-cell-tropic, cytopathic, and syncytia-inducing virus population as humans progress to aids. this suggests that changes in virus phenotype may influence disease. because simian immunodeficiency virus (siv) infection in macaques is a common model system for hiv-1 pathogenesis, we determined whether siv infection in macaques that develop simian ... | 1995 | 7886956 |
| protection of rhesus macaques from siv infection by immunization with different experimental siv vaccines. | the immunogenicity and efficacy of an inactivated whole sivmac (32h) preparation adjuvanted with muramyl dipeptide (siv-mdp) and a gp120-enriched sivmac (32h) iscom preparation (siv-iscom), were compared by immunizing four rhesus macaques (macaca mulatta) four times with siv-mdp and four others in the same way with siv-iscom. two monkeys immunized with whole inactivated measles virus (mv) adjuvanted with mdp (mv-mdp) and two monkeys immunized with mv-iscom served as controls. in the siv-iscom-im ... | 1994 | 7887023 |
| early stages of feline immunodeficiency virus infection in lymph nodes and spleen. | analysis of the early stages of infection within the lymphoid organs is crucial for the understanding of the physiopathology of hiv infection. such analysis can only be performed using animal models. cats were infected with two strains of fiv and killed at regular intervals for a classic pathologic study along with a quantification of the viral load by in situ hybridization in the spleen and the lymph nodes. the pathological study showed a persistent follicular reaction, which peaked 15 days pos ... | 1994 | 7888233 |
| pathogenicity of live, attenuated siv after mucosal infection of neonatal macaques. | adult macaques do not develop disease after infection with a nef deletion mutant of the simian immunodeficiency virus (siv) and are protected against challenge with pathogenic virus. this finding led to the proposal to use nef-deleted viruses as live, attenuated vaccines to prevent human acquired immunodeficiency syndrome (aids). in contrast, neonatal macaques developed persistently high levels of viremia after oral exposure to and siv nef, vpr, and negative regulatory element (nre) deletion mut ... | 1995 | 7892606 |
| antibodies to the putative siv infection-enhancing domain diminish beneficial effects of an siv gp160 vaccine in rhesus macaques. | to demonstrate that antibodies against amino acids (aa) 603-622 of the siv gp41 transmembrane glycoprotein enhance infection of siv in vivo. | 1995 | 7893438 |
| bone marrow monocyte/macrophages are an early cellular target of pathogenic and nonpathogenic isolates of simian immunodeficiency virus (sivmac) in rhesus macaques. | hematopoietic abnormalities are a common complication of human immunodeficiency virus infection in humans. however, the pathogenesis of these abnormalities remains unclear. simian immunodeficiency virus (siv) infection of rhesus macaques is a well-recognized animal model for acquired immunodeficiency syndrome. our previous studies have determined that in early siv infection, rhesus macaques develop peripheral blood and bone marrow pathologic changes within the first 14 days after intravenous ino ... | 1995 | 7898051 |
| plasma amino acid dysregulation after lentiviral infection. | the absence of aids-like symptoms in hiv-infected chimpanzees and siv-infected african green monkeys (agms) may provide important clues about the pathogenic mechanism of aids and about mechanisms of resistance. hiv-infected persons and siv-infected rhesus macaques have, on the average, markedly decreased cysteine, cystine, and glutathione levels and elevated plasma glutamate concentrations. glutamate inhibits the membrane transport of cystine and a combination of low plasma glutamate and high cy ... | 1993 | 7903043 |
| the importance of nef in the induction of human immunodeficiency virus type 1 replication from primary quiescent cd4 lymphocytes. | the viral regulatory gene, nef, is unique to the human immunodeficiency viruses (hiv) and their related primate lentiviruses. expression of the nef gene has been shown to be essential to the maintenance of high levels of virus replication and the development of pathogenesis in the animal model of simian immunodeficiency virus (siv) infection. in contrast to this in vivo model, the use of standard t cell culture systems to study nef function in vitro has produced a spectrum of contradictory resul ... | 1994 | 7903679 |
| the role of cd4 in hiv binding and entry. | the primary cellular receptor for the human and simian immunodeficiency viruses hiv-1, hiv-2 and siv is the cd4 antigen (sattentau et al. 1988; sattentau & weiss 1988). hiv infection of cd4+ cells is initiated by binding of the virus to the cell surface, via a high-affinity interaction between the first domain of cd4 and the hiv outer envelope glycoprotein, gp120. the use of a soluble recombinant form of cd4 (scd4) as a receptor mimic has simplified the analysis of receptor binding and post-bind ... | 1993 | 7904348 |
| is cd4 sufficient for hiv entry? cell surface molecules involved in hiv infection. | hiv-1, hiv-2 and siv each bind to cd4 as the first step in virus entry. however, alternative receptors may also be used. hiv-1 binds to glycolipids with terminal galactosylceramide residues on neural cells; opsonized virus binds to fc receptors; hiv-2 can infect certain cd4-negative cells. further receptors may also play a role in cd4-mediated infection, including cell adhesion molecules and possibly cell surface proteinases. after binding to cd4, immunodeficiency viruses require secondary molec ... | 1993 | 7904349 |
| mhc-i non-restricted cytotoxic activity in macaca sylvana experimentally inoculated with hiv2 and siv/mac. | the anti-retrovirus cell-mediated immunity was repeatedly investigated in seven monkeys (macaca sylvana). four of these animals were injected with cell-free supernatants containing human immunodeficiency viruses: two monkeys received hiv1 bru (2.5 x 10(6) cpm), two received hiv2 rod (1.5 x 10(6) cpm). two additional animals were injected with a cell-free supernatant containing simian immunodeficiency virus siv/mac 251 (1.5 x 10(6) cpm) and the last animal served as control. the four macaques inf ... | 1993 | 7905683 |
| the simian immunodeficiency virus nef protein promotes degradation of cd4 in human t cells. | expression of the nef protein encoded by human and simian immunodeficiency viruses results in the specific down-regulation of cd4 from the cell surface in both lymphoid and non-lymphoid cells. in this report, we examine the biosynthesis and cell surface expression of cd4 in the human t cell line, cem-ss, that has been stably transduced with the siv nef gene. quantification of cd4 in nef-expressing cells reveals that the steady state level of cd4 is significantly reduced as compared to control tr ... | 1994 | 7905875 |
| cytotoxic t-cell response and aids-free survival in simian immunodeficiency virus-infected macaques. | to determine whether cytotoxic t lymphocytes have a beneficial effect during infection with the simian immunodeficiency virus (siv) in macaques. | 1993 | 7909229 |
| expression of biologically active envelope glycoprotein from the acutely pathogenic simian immunodeficiency virus sivsmmpbj. | the full-length envelope (env) gene from the most acutely pathogenic primate lentivirus described so far, the simian immunodeficiency virus sivsmmpbj14 was expressed by a recombinant vaccinia virus vector (vv-env4) and was completely characterized as a previous step for its use as an immunogen in vaccination trials. radioimmunoprecipitation and western blot experiments indicated that sivsmmpbj gp160 precursor was processed into gp120 and gp41 subunits, and that gp120 was released into the medium ... | 1994 | 7911608 |
| cd8+ t lymphocytes of african green monkeys secrete an immunodeficiency virus-suppressing lymphokine. | following natural and experimental infection by simian immunodeficiency virus sivagm of african green monkeys (agms), the natural host, there is no evidence for the development of an immunodeficiency. within the framework of our studies on human immunodeficiency virus (hiv)/siv pathogenesis, we investigated the influence of cd8 t lymphocytes on sivagm replication in agm cd4 t lymphocytes in vitro. the following observations were made: (i) peripheral blood mononuclear cells from both seronegative ... | 1994 | 7913749 |
| an acutely lethal simian immunodeficiency virus stimulates expansion of v beta 7- and v beta 14-expressing t lymphocytes. | sivsmmpbj14, a variant simian immunodeficiency virus isolated from a pig-tailed macaque, stimulates the proliferation of macaque t lymphocytes in vitro and induces an acutely lethal disease in macaques characterized, in part, by lymphadenopathy and splenomegaly. to determine whether sivsmmpbj14 exhibits superantigen-like activity, in vitro and in vivo studies of t-cell receptor v beta repertoire were undertaken using pcr-based quantitative methods. whereas in vitro phytohemagglutinin stimulation ... | 1994 | 7914369 |
| malignant lymphoma associated with experimentally induced feline immunodeficiency virus infection. | a malignant low-grade b-cell lymphoma, primarily in the kidney, is described in a specific-pathogen-free cat experimentally infected with feline immunodeficiency virus (fiv) and free of feline leukaemia virus. at the time of diagnosis the cat showed a marked reduction of circulating cd4+ t lymphocytes, was 2 years old, and had been infected for 18 months. fiv was isolated both from peripheral blood mononuclear cells and the neoplastic tissue. dna of fiv gag gene was detected in several specimens ... | 1994 | 7914523 |
| the role of upstream u3 sequences in the pathogenesis of simian immunodeficiency virus-induced aids in rhesus monkeys. | the nef reading frame overlaps about 70% of the u3 region of the 3' long terminal repeat (ltr) in primate lentiviruses. we investigated the functional role of these overlapping u3 sequences by analyzing the properties of three mutant forms of the pathogenic sivmac239 clone. in mutant uscon, 90 of 275 bp in the upstream sequences (us) of u3 were changed in a conservative fashion without changing the predicted nef coding sequence. in mutant usnon, 101 of 275 bp in this region were changed in a non ... | 1994 | 7914551 |
| variable course of primary simian immunodeficiency virus infection in lymph nodes: relation to disease progression. | to investigate the dynamics of spread of simian immunodeficiency virus (siv) in the lymphoid organs, we sequentially analyzed the viral burden in lymph nodes (ln) of eight rhesus macaques inoculated intravenously with a high or low dose of the pathogenic sivmac 251 isolate. for each animal, four axillary or inguinal ln were collected during the first weeks of infection and a fifth ln was taken 6 or 8 months later to estimate disease progression. measurement of siv rna by in situ hybridization sh ... | 1994 | 7916061 |
| serum antibodies from ms patients do not recognize htlv-i, hiv-1, hiv-2 and siv. | a retroviral aetiology has been proposed for multiple sclerosis (ms). although there is as yet no definitive evidence of viral involvement, there have been preliminary reports of antiretroviral antibody detection in sera from ms patients. such sera have, for example, been found to react with htlv-i. we here describe investigations involving various immunological techniques which attempt to confirm the virus-specific nature of these antibodies against a range of human and macaque retroviruses. se ... | 1994 | 7917220 |
| analysis of cytotoxic t lymphocyte responses to siv proteins in siv-infected macaques using antigen-specific stimulation with recombinant vaccinia and fowl poxviruses. | methods to analyze cd8+ ctl responses to simian immunodeficiency virus (siv)-encoded proteins are essential to understand lentivirus immunopathogenesis and protective immune responses. recombinant infectious shuttle vectors are useful for analyzing ctl responses to many viruses, including hiv. therefore, ctl responses in siv-infected macaca fascicularis to siv env and siv gag/pol were evaluated using specific antigen stimulation with recombinant vaccinia (rvv) and fowl poxviruses (rfpv) containi ... | 1994 | 7917517 |
| characterization of simian immunodeficiency virus (siv) infected aa-2 cells by sem and immunoelectron microscopy. | the ultrastructural features of aa-2 cells infected with either of two strains of simian immunodeficiency virus (sivmne-e11s or sivsmm-pbj) were examined by scanning electron microscopy (sem). transformed cd4+ human b lymphocytes (aa-2) were inoculated with siv and observed at 2, 4, and 7 days post-inoculation (dpi). infected aa-2 cells were distinguished by the progressive loss of microvilli, and variable numbers of free or protruding spherical particles measuring 90-120nm in diameter along the ... | 1994 | 7919531 |
| survey of simian immunodeficiency virus among nonhuman primate populations. | | 1994 | 7924421 |
| mucosal transmission of simian immunodeficiency virus. | | 1994 | 7924422 |
| cd4+ t cell responses to simian immunodeficiency virus. | | 1994 | 7924425 |
| towards a vaccine against aids: lessons from simian immunodeficiency virus vaccines. | | 1994 | 7924428 |
| pathology of simian immunodeficiency virus induced disease. | | 1994 | 7924429 |
| sivsmmpbj14: an atypical lentivirus. | siv-pbj14 is atypical for a lentivirus in that infection of pig-tailed macaques usually does not result in long-term progressive disease; however, this model may potentially provide valuable information about the pathogenesis of hiv and the development of aids. by capitalizing on some of the unique properties of the virus and the model system discussed above, new insights may be gained in: (a) understanding pathogenic mechanisms of acute lentiviral infections, (b) dissecting lentivirus-host cell ... | 1994 | 7924430 |
| dna of lymphoma-associated herpesvirus (hvmf1) in siv-infected monkeys (macaca fascicularis) shows homologies to ebna-1, -2 and -5 genes. | we have characterized a new epstein-barr-virus(ebv)-like herpesvirus associated with lymphomas of siv-infected cynomolgus (macaca fascicularis) monkeys and propose that this virus is designated herpesvirus macaca fascicularis i (hvmfi). genomic regions in hvmf1 of potential significance for tumor pathogenesis were analyzed by southern blotting, pcr and sequencing, and compared with human ebv dna. virus from 7 siv-associated lymphomas and one lymphoma-derived cell line were shown to share homolog ... | 1994 | 7927931 |
| sexual transmission of sivagm in wild grivet monkeys. | this study reports the prevalence of simian immunodeficiency virus and the relationship of serostatus to age and sex among a wild population of ethiopian grivet monkeys (cercopithecus aethiops aethiops). seropositivity paralleled patterns of sexual activity, being nearly universal in females of reproductive age, and absent in all males except those that were fully adult. one female seroconverted between two capture seasons at an age consistent with first breeding. our findings support a predomin ... | 1994 | 7932633 |
| spontaneous renal lymphosarcoma in a juvenile cynomolgus monkey (macaca fascicularis). | spontaneous lymphosarcoma, likely of renal origin, was diagnosed in a naive, juvenile, male cynomolgus monkey (macaca fascicularis). histologically, renal architecture was effaced by dense infiltrating sheets of plump cells with indistinct borders and scant amphophilic cytoplasm. mitoses were uncommon. similar neoplastic infiltrates were also present in the right renal cortex, one adrenal medulla, the prostate, seminal vesicles, myocardium, and the pulmonary interstitium. serological tests were ... | 1994 | 7932641 |
| a partially attenuated simian immunodeficiency virus induces host immunity that correlates with resistance to pathogenic virus challenge. | three infectious, attenuated molecular clones of simian immunodeficiency virus (sivmac) were tested for viral and host determinants of protective immunity. the viruses differed in degree of virulence from highly attenuated to moderately attenuated to partially attenuated. levels of immune stimulation and antiviral immunity were measured in rhesus macaques inoculated 2 years previously with these viruses. monkeys infected with the highly attenuated or moderately attenuated viruses had minimal lym ... | 1994 | 7933084 |
| selective amplification of simian immunodeficiency virus genotypes after intrarectal inoculation of rhesus monkeys. | animal models for sexual transmission of human immunodeficiency virus can define the influences of virus type, dose, and route of inoculation on infection and clinical outcome. we used an uncloned simian immunodeficiency virus stock (sivmac) to inoculate cells in vitro and to inoculate rhesus monkeys by intravenous and intrarectal routes. the distribution of virus genotypes present in each of these infection examples was characterized by dna sequence analysis of viral long terminal repeats (ltrs ... | 1994 | 7933157 |
| biological, molecular, and structural analysis of a cytopathic variant from a molecularly cloned simian immunodeficiency virus. | | 1994 | 7933160 |
| establishing specific retrovirus-free breeding colonies of macaques: an approach to primary screening and surveillance. | for reasons of occupational safety and animal health, as well as to improve the quality of nonhuman primates used in biomedical research, the establishment and maintenance of specific retrovirus-free breeding colonies of macaques (genus macaca) are now high priorities. sensitive and specific screening tests are now available for use in identifying macaques infected with the exogenous simian retroviruses simian immunodeficiency virus (siv), simian t-lymphotropic virus (stlv), and simian type d re ... | 1994 | 7933966 |
| construction and use of integrative vectors to express foreign genes in mycobacteria. | we have constructed a mycobacterial integrative vector by placing two copies of the insertion sequence is900 flanking a kanamycin-resistance gene into a 'suicide' vector unable to replicate in mycobacteria. the mycobacterium leprae gene encoding the m. leprae 18 kda protein was cloned between the two copies of is900 to provide expression signals. constructs were introduced into mycobacterium species smegmatis, vaccae and bovis bcg by electroporation and selection for kanamycin resistance. the ex ... | 1993 | 7934874 |
| programmed cell death and aids: significance of t-cell apoptosis in pathogenic and nonpathogenic primate lentiviral infections. | we have proposed that inappropriate induction of programmed cell death (pcd) or apoptosis, a physiological cell-suicide process, may play a role in the pathogenesis of aids. this model has been supported by several reports of abnormal levels of pcd in vitro in both cd4+ and cd8+ t cells from human immunodeficiency virus type 1 (hiv-1)-infected persons. to further assess the significance of such a process in aids pathogenesis, in vitro pcd was compared in hiv-1-infected persons and in various pri ... | 1994 | 7937784 |
| encephalomyelitis due to a sarcocystis neurona-like protozoan in a rhesus monkey (macaca mulatta) infected with simian immunodeficiency virus. | a captive-born rhesus monkey (macaca mulatta) experimentally infected with simian immunodeficiency virus developed neurologic abnormalities approximately seven months postinoculation. a chronic necrotizing encephalomyelitis with intralesional protozoal schizonts was diagnosed histologically. the protozoa was identified as sarcocystis neurona based on its morphologic characteristics by light and electron microscopic examination, the developmental stages of the schizonts, and positive staining wit ... | 1994 | 7943553 |
| optic nerve morphometry following axonal degeneration from saids in rhesus monkeys. | in order to further study aids (acquired immunodeficiency syndrome) related neuropathologic findings, specifically progressive diffuse leuko-encephalopathy (pdl) and optic neuropathy, ten macaque monkeys (macaca mulatta) were infected with simian immunodeficiency virus (siv), observed for varying periods, and then sacrificed and tissue prepared for analysis. a marked difference from human aids pathology was found: in all monkeys, there was significant peripheral axonal dropout, as opposed to rel ... | 1994 | 7956315 |
| localization of viral protein x in simian immunodeficiency virus macaque strain and analysis of its packaging requirements. | simian immunodeficiency virus (siv) and human immunodeficiency virus type 2 (hiv-2) encode the accessory viral protein x (vpx) known to be incorporated into virions in amounts comparable to those of the gag proteins. the localization of vpx within sivmac-infected hut-78 cells and sivmac virions was studied by immunoelectron microscopy. vpx appeared to be associated with extracellular virions as well as budding viral particles at the surface of infected cells. immunolabelling of purified viral co ... | 1994 | 7964605 |
| effects of vif mutations on cell-free infectivity and replication of simian immunodeficiency virus. | to investigate the function of the vif protein of the simian immunodeficiency virus (siv), mutations were introduced into the sivmac239 vif gene without affecting the reading frames of other overlapping genes. the phenotypes of these mutant viruses were examined with respect to viral replication and the expression and processing of viral proteins. transfection of vif-mutant proviral dna into established t cell lines resulted in a significant delay in the onset of virus replication compared to th ... | 1994 | 7965633 |
| early activation of pbmc and appearance of antiviral cd8+ cells influence the prognosis of siv-induced disease in rhesus macaques. | we studied 15 macaques inoculated with siv and identified three phases of infection. phase 1 was characterized by activated lymphocytes in blood and infected cells in the csf. in phase 2, activated cells were not detected but virus was recovered from mitogen-stimulated pbmc, while in phase 3, virus was recovered from mitogen-stimulated pbmc only after depletion of cd8+ lymphocytes, indicating effective control of the virus in peripheral blood. early development of phase 3 status correlated with ... | 1994 | 7966224 |
| cellular immune responses in rhesus macaques infected rectally with low dose simian immunodeficiency virus. | monkeys infected rectally with low dose simian immunodeficiency virus (siv) were resistant to high dose challenge with siv. peripheral blood mononuclear cells (pbmc) from two of four challenged monkeys were unable to support siv replication in vitro unless cultures were depleted of cd8+ lymphocytes. monkeys that had survived high dose rectal infection with siv also suppressed virus replication in cultured pbmc. pbmc from uninfected monkeys supported virus replication in both unfractionated and c ... | 1994 | 7966226 |
| 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 |
| passive immunization of macaques against siv infection. | passive immunization with plasma from an inactivated-whole sivmac vaccine protected monkey conferred complete or partial protection to rhesus macaques challenged intravenously 4 or 18 hours later with 10 aid50 of homologous cell-free virus. in contrast, passive immunization with inactivated plasma or purified immunoglobulin (ig) from sivmac infected asymptomatic monkeys failed to protect any recipients similarly challenged and may have enhanced infection and accelerated disease. administered 24 ... | 1994 | 7966232 |
| comparison of the efficacy of azt and pmea treatment against acute sivmne infection in macaques. | the antiretroviral drugs azidothymidine (azt) and 9-(-2-phosphonyl-methoxyethyl)adenine (pmea) were individually tested for prevention of simian immunodeficiency virus (sivmne) infection in macaques (macaca fascicularis). macaques were pretreated with either drug before inoculation with sivmne, and drug treatment was continued for four weeks. the virus, antibody, and clinical status of the macaques was monitored for up to 36 weeks following inoculation. while azt prophylaxis resulted in reduced ... | 1994 | 7966233 |
| primary cultures of rhesus placental syncytiotrophoblasts are permissive for siv infection. | primary cultures of rhesus syncytiotrophoblasts incubated with sivdeltab670, sivmac251, or sivmac239 produced readily detectable virus in the supernatant for up to three weeks after infection. at four weeks, cells generally failed to release virus but placental cell lysates and placental cells cocultured for 24 hours with uninfected cem x 174 cells were able to transmit infection. the presence of virus was confirmed by electron microscopy and pcr amplification of viral sequences from trophoblast ... | 1994 | 7966236 |
| immunization with whole inactivated vaccine protects from infection by siv grown in human but not macaque cells. | homologous sivsm stocks were generated by passage of a macaque isolate of sivsm (sivsm/e660) in human cem x 174 cells or macaque peripheral blood mononuclear cells. macaques were immunized with whole inactivated siv vaccine consisting of virus generated by transfection of cem x 174 cells with the sivsmh4 clone and were challenged with either cell-free stock. only vaccinees challenged with virus generated in human cells were protected from infection. this confirms the species-specificity of whole ... | 1994 | 7966237 |
| infectivity of titered doses of simian immunodeficiency virus clone e11s inoculated intravenously into rhesus macaques (macaca mulatta). | the macaque infectious dose (mid) of a single-cell clone of simian immunodeficiency virus isolated from a pig-tailed macaque (siv/mne clone e11s) was determined in rhesus macaques (macaca mulatta). twenty-one macaques were inoculated with 10-fold dilutions of the virus stock (three or four animals per dose). the virologic and clinical status of these animals was monitored for 26 weeks. the 25% mid (mid25) occurred at a 10(5)-fold dilution of the viral stock. | 1994 | 7966238 |
| mucosal immunization with a live, virulence-attenuated simian immunodeficiency virus (siv) vaccine elicits antiviral cytotoxic t lymphocytes and antibodies in rhesus macaques. | an effective aids vaccine must protect against sexual transmission of human immunodeficiency virus (hiv). therefore, vaccine regimens which stimulate antiviral immunity in the genital tract as well as in peripheral blood and systemic lymphoid tissues are needed. here, we describe a method of immunization by direct inoculation of the vaginal submucosa with a live attenuated siv, sivmac1a11. immunization by this route generated low levels of siv-specific igg and iga antibodies in serum and vaginal ... | 1994 | 7966240 |
| enhanced responsiveness to nuclear factor kappa b contributes to the unique phenotype of simian immunodeficiency virus variant sivsmmpbj14. | infection with a variant of simian immunodeficiency virus, sivsmmpbj14, leads to severe acute disease in macaques. this study was designed to investigate the functional significance of previously described mutations in the viral long terminal repeat (ltr) and to elucidate their contribution to the unique phenotype of sivsmmpbj14. ltr-directed transcription was measured by using luciferase reporter constructs that were transiently transfected into cultured cells. in a wide range of cell types, th ... | 1994 | 7966569 |
| neurovirulent simian immunodeficiency virus replicates productively in endothelial cells of the central nervous system in vivo and in vitro. | the perivascular location of human immunodeficiency virus-infected cells suggests that the virus enters the central nervous system (cns) by traversing the blood-brain barrier (bbb). in this study, the simian immunodeficiency virus (siv) macaque model was used to determine whether siv infects cns endothelial cells. siv rna was detected in capillary endothelial cells in brain sections from animals parenterally inoculated with a neurovirulent strain of siv by double immunohistochemistry and in situ ... | 1994 | 7966612 |
| infection of a yellow baboon with simian immunodeficiency virus from african green monkeys: evidence for cross-species transmission in the wild. | many african primates are known to be naturally infected with simian immunodeficiency viruses (sivs), but only a fraction of these viruses has been molecularly characterized. one primate species for which only serological evidence of siv infection has been reported is the yellow baboon (papio hamadryas cynocephalus). two wild-living baboons with strong sivagm seroreactivity were previously identified in a tanzanian national park where baboons and african green monkeys shared the same habitat (t. ... | 1994 | 7966642 |
| physical interaction of the hiv-1 nef protein with beta-cop, a component of non-clathrin-coated vesicles essential for membrane traffic. | nef is a 27-kda myristylated protein conserved in most human immunodeficiency virus (hiv)-1, hiv-2, and simian immunodeficiency virus isolates. simian immunodeficiency virus nef is required in macaques for both high viral load and full pathological effects. nef down-regulates the cell surface expression of cd4 by a post-translational mechanism that is not yet fully elucidated. we have used the yeast two-hybrid system to identify cellular proteins that interact with nef. a cdna was isolated which ... | 1994 | 7982906 |
| characterization of nef sequences in long-term survivors of human immunodeficiency virus type 1 infection. | studies with the simian immunodeficiency virus have shown that nef deletion results in a low level of viremia and a lack of disease progression in monkeys. given the similarity of this clinical profile to that observed in long-term survivors of human immunodeficiency virus type 1 (hiv-1) infection, we sought to examine the nef gene in 10 patients who are clinically healthy and immunologically normal despite 12 to 15 years of infection. pcr and dna sequencing were used to determine nef sequences ... | 1995 | 7983771 |
| high-titer immune responses elicited by recombinant vaccinia virus priming and particle boosting are ineffective in preventing virulent siv infection. | eighteen rhesus monkeys were vaccinated with recombinant vaccinia viruses expressing sivmac antigens in 3 separate rounds of experiments. twelve of the monkeys were primed with a trivalent vaccinia virus recombinant expressing gag, pol, and env polypeptides that can assemble into siv pseudovirion particles and boosted with siv particles in adjuvant. four of the monkeys were primed with different vaccinia virus recombinants expressing env or gag+env followed by siv particle boosts; two received v ... | 1994 | 7986589 |
| induction of antigen-specific killer t lymphocyte responses using subunit sivmac251 gag and env vaccines containing qs-21 saponin adjuvant. | subunit vaccines based on recombinant proteins have proved useful for inducing antibody responses and they are safe for widespread use because they do not contain any live components. unfortunately, they do not typically induce the types of cell-mediated immune responses required to control viral pathogens; specifically, they do not induce cd8+ cytotoxic t lymphocyte (ctl) responses. to increase the immunogenicity of recombinant proteins, we have used the qs-21 saponin adjuvant in subunit vaccin ... | 1994 | 7986590 |
| macrophage function in simian aids. killing defects in vivo are independent of macrophage infection, associated with alterations in th phenotype, and reversible with ifn-gamma. | infection of macrophages (m phi) in vitro with m phi-tropic isolates of simian immunodeficiency virus (siv) did not affect killing of cryptococcus neoformans up to 16 days after inoculation (p < 0.05). conversely, alveolar m phi from animals with siv-induced aids killed c. neoformans less efficiently (10.4 +/- 2.8% killing) and, when stimulated with phorbol myristate, produced less superoxide anion (o2-; 0.15 +/- 0.02 o2-/h/mg m phi protein) than m phi from uninfected monkeys (21.8 +/- 1.6% kill ... | 1994 | 7989775 |
| the repertoire of cytotoxic t lymphocytes in the recognition of mutant simian immunodeficiency virus variants. | the importance of the repertoire of a primed, aids virus-specific population of ctl in the recognition of emerging mutant viruses was assessed in simian immunodeficiency virus (siv)-infected rhesus monkeys. these studies were done by using the well-characterized ctl recognition of the sivmac gag peptide 11c (p11c) epitope in rhesus monkeys expressing the mhc class i molecule mamu-a*01. lysis of peptide-pulsed targets by bulk pbl effector cells from sivmac-infected, mamu-a*01+ monkeys was signifi ... | 1994 | 7989780 |
| bicyclic imidazo derivatives, a new class of highly selective inhibitors for the human immunodeficiency virus type 1. | in the search for new antiviral agents against human immunodeficiency virus, different members of two imidazoheterocycle families (imidazothiazoles, imidazopyridines) have been found to display potent inhibitory effects on the replication of hiv-1. three of these derivatives, which show significant anti-hiv-1 activity, have been chosen for further studies. the analysis of these compounds and their comparison to azt and tibo revealed that these bicyclic imidazo derivatives represent a class of hi ... | 1994 | 7993073 |