Publications

viral factors determine progression to aids in simian immunodeficiency virus-infected newborn rhesus macaques.	to evaluate how viral variants may affect disease progression in human pediatric aids, we studied the potential of three simian immunodeficiency virus (siv) isolates to induce simian aids in newborn rhesus macaques. the three virus isolates were previously shown to range from pathogenic (sivmac251 and sivmac239) to nonpathogenic (sivmac1a11) when inoculated intravenously into juvenile and adult rhesus macaques. six newborn macaques inoculated with pathogenic, uncloned sivmac251 developed persist ...	1995	7769679
repeated exposure of rhesus macaques to low doses of simian immunodeficiency virus (siv) did not protect them against the consequences of a high-dose siv challenge.	as part of an in vivo titration study of the macaque simian immunodeficiency virus (sivmac) strain 251/spl, macaques were inoculated intravenously with various dilutions of this infectious sivmac. seven animals received dilutions from 10(-3) to 10(-6) of sivmac251/spl. two monkeys infected with the 10(-3) dilution of sivmac exhibited a productive infection as indicated by seroconversion, detection of genomic rna and proviral dna and positive virus isolation. these animals showed a cytotoxic t ce ...	1995	7782761
emergence of antigenic variants of simian immunodeficiency virus (sivmac) in a seronegative macaque after sivmac239 infection.	infection with the macaque strain of the simian immunodeficiency virus (sivmac) induces simian immunodeficiency syndrome in rhesus macaques. this report describes the isolation and identification of antigenic variants of sivmac in one of the infected monkeys (macaque #22803). eight naive rhesus monkeys were inoculated with a titered viral stock of the molecularly cloned sivmac239. standard serological analysis revealed that all but two were seroconverted. western blot analysis confirmed the sero ...	1994	7787884
zidovudine treatment prolongs survival and decreases virus load in the central nervous system of rhesus macaques infected perinatally with simian immunodeficiency virus.	to assess the potential therapeutic effects of zidovudine, rhesus macaques were inoculated with simian immunodeficiency virus (siv) strain smm/b670 at birth and infused either continuously or intermittently with zidovudine for 6-7 months. zidovudine did not prevent infection but did significantly increase survival time, which was associated with lower serum p26 viral core antigen levels, a lower virus burden in the cerebrospinal fluid (csf), and lower csf quinolinic acid levels than in untreated ...	1995	7797947
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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-a01. lysis of peptide-pulsed targets by bulk pbl effector cells from sivmac-infected, mamu-a01+ monkeys was signifi ...	1994	7989780
induction of humoral and cellular immunity to simian immunodeficiency virus: what are the requirements for protection?	in an effort to produce a strong humoral and cellular immune response that might protect against simian immunodeficiency virus (siv) infection, groups of five rhesus macaques each were immunized intramuscularly at 0, 2 and 6 months with 100 micrograms of an inactivated preparation of siv/delta b670 in either an oil-in-water emulsion with ribi detox, containing mycobacterial cell wall skeleton and monophosphoryl lipid a (cws/mpl) (group a) or a water-in-oil emulsion with incomplete freund's adjuv ...	1994	7998424
major histocompatibility complex class i-associated vaccine protection from simian immunodeficiency virus-infected peripheral blood cells.	to evaluate the effectiveness of vaccine protection from infected cells from another individual of the same species, vaccinated rhesus macaques (macaca mulatta) were challenged with peripheral blood mononuclear cells from another animal diagnosed with acquired immune deficiency syndrome (aids). half of the simian immunodeficiency virus (siv)-vaccinated animals challenged were protected, whereas unprotected vaccinates progressed as rapidly to aids. protection was unrelated to either total antibod ...	1994	8046353
early events in tissues during infection with pathogenic (sivmac239) and nonpathogenic (sivmac1a11) molecular clones of simian immunodeficiency virus.	the extent of virus replication, tissue distribution, localization of virus within tissues, and the presence of pathological lesions was examined early after experimental infection of rhesus monkeys with simian immunodeficiency virus (siv). three strains of siv were used: molecularly cloned pathogenic sivmac239; molecularly cloned nonpathogenic sivmac1a11; and uncloned pathogenic sivmac. the major targets of infection in all animals at 2 weeks postinoculation were the thymus and spleen. the dist ...	1994	8053500
[the immunological manifestations and cytological characteristics of infection caused by the simian immunodeficiency virus (siv) in rhesus monkeys].	the results of immunological and morphological studies of asian macaques (macaca mulatta) infected by simian immunodeficiency virus (siv) are summarized in this review of literature. this virus causes development of the immunodeficiency disease that closely resembles human aids. immunological parameters (cd count, antibody response etc.) are described promoting prediction of progression of immunodeficiency in monkeys. the morphological features of injury of internal organs indicate that siv-indu ...	1993	8066812
mucosal infection of neonatal rhesus monkeys with cell-free siv.	although the mechanisms for maternal transmission are unknown, approximately half of the infants congenitally infected with the human immunodeficiency virus type 1 (hiv-1) seem to become infected late in gestation or during delivery. previously, we have developed a rhesus monkey model for congenital infection by injecting cell-free simian immunodeficiency virus (siv) directly into amniotic fluid. our results suggested that fetal infection may have occurred via skin or mucous membrane exposure. m ...	1994	8068415
intravaginal inoculation of rhesus macaques with cell-free simian immunodeficiency virus results in persistent or transient viremia.	the simian immunodeficiency virus (siv)-rhesus macaque model of heterosexual human immunodeficiency virus transmission consists of atraumatic application of cell-free sivmac onto the intact vaginal mucosa of mature female rhesus macaques. this procedure results in systemic infection, and eventually infected animals develop the clinical signs and pathologic changes of simian aids. to achieve 100% transmission with the virus stocks used to date, multiple intravaginal inoculations are required. the ...	1994	8083977
mucosal model of genital immunization in male rhesus macaques with a recombinant simian immunodeficiency virus p27 antigen.	human immunodeficiency virus (hiv) can be transmitted through infected seminal fluid or vaginal or rectal secretions during heterosexual or homosexual intercourse. to prevent mucosal transmission and spread to the regional lymph nodes, an effective vaccine may need to stimulate immune responses at the genitourinary mucosa. in this study, we have developed a mucosal model of genital immunization in male rhesus macaques, by topical urethral immunization with recombinant simian immunodeficiency vir ...	1994	8107223
incomplete protection, but suppression of virus burden, elicited by subunit simian immunodeficiency virus vaccines.	we compared the efficacy of immunization with either simian immunodeficiency virus (siv) env glycoprotein (env), env plus gag proteins (gag-env), or whole inactivated virus (wiv), with or without recombinant live vaccinia vector (vv) priming, in protecting 23 rhesus macaques (six vaccine and two control groups) from challenge with sivmac251 clone bk28. vaccination elicited high titers of syncytium-inhibiting and anti-env (gp120/gp160) antibodies in all vaccinated macaques and anti-gag (p27) anti ...	1994	8107246
upstream u3 sequences in simian immunodeficiency virus are selectively deleted in vivo in the absence of an intact nef gene.	major transcriptional control elements are located within the u3 region of the long terminal repeats (ltrs) of lentivirus and other retroviral genomes. the nef auxiliary gene of simian immunodeficiency virus (siv) and human immunodeficiency virus overlaps about 70% of the 450- to 560-bp-long u3 region present in these primate lentiviruses. we analyzed viral dna sequences present in rhesus monkeys infected with a mutant of sivmac containing a 182-bp deletion in the region of nef that does not ove ...	1994	8107267
cytopathologic and neurochemical correlates of progression to motor/cognitive impairment in siv-infected rhesus monkeys.	neurochemical, pathologic, virologic, and histochemical correlates of simian immunodeficiency virus (siv)-associated central nervous system (cns) dysfunction were assessed serially or at necropsy in rhesus monkeys that exhibited motor and cognitive deficits after siv infection. some infected monkeys presented with signs of acquired immunodeficiency disease (aids) at the time of sacrifice. seven of eight animals exhibited motor skill impairment which was associated with elevated quinolinic acid i ...	1994	8120538
molecular and biological characterization of simian immunodeficiency virus macaque strain 32h proviral clones containing nef size variants.	the proviral genome of the 32h reisolate of simian immunodeficiency of macaques (sivmac32h) has been cloned and sequenced. including both long terminal repeats, it is 10277 base pairs in length and contains open reading frames for all known siv genes (gag, pol, vif, vpx, vpr, tat, rev, env and nef). this is the first report of an infectious sivmac molecular clone which contains no premature termination codons. three molecular clones of sivmac32h have been constructed differing in sequence only w ...	1994	8126450
simian immunodeficiency virus as a model for vaccination against hiv. induction in rhesus macaques of gag- or nef-specific cytotoxic t lymphocytes by lipopeptides.	the protection against infection by hiv probably requires the induction of both neutralizing abs and ctl responses. vaccination by attenuated hiv is hardly acceptable and the use of viral genes inserted in recombinant living vectors needs further development, especially with respect to safety. the peptidic vaccination is a promising approach but free peptides are usually poorly immunogenic. because potent immune responses have been obtained in mice with modified peptides such as lipopeptides, we ...	1994	8133061
immunopathogenic events in acute infection of rhesus monkeys with simian immunodeficiency virus of macaques.	infection of the rhesus monkey with simian immunodeficiency virus of macaques (sivmax) was employed to explore the early immune events associated with the initial containment of an acute aids virus infection. in nine rhesus monkeys infected intravenously with uncloned sivmac strain 251, high-level p27 plasma antigenemia was usually detected transiently from approximately day 7 through day 21 following virus inoculation. sivmac replication in lymph nodes measured by in situ rna hybridization clos ...	1994	8139022
pathology and localization of simian immunodeficiency virus in the reproductive tract of chronically infected male rhesus macaques.	despite the fact that human immunodeficiency virus (hiv) is transmitted by sexual contact, the biology of this mode of transmission remains largely undefined. hiv is present in semen in both cell-free and cell-associated forms and can be isolated from asymptomatic individuals and aids patients. the source of hiv in semen and the target cells for hiv transmission to men are unknown. epidemiologic studies have shown that in men, the presence of an intact foreskin is associated with increased risk ...	1994	8139266
primary acute simian immunodeficiency virus infection of intestinal lymphoid tissue is associated with gastrointestinal dysfunction.	human immunodeficiency virus (hiv)-associated intestinal abnormalities can occur before immunodeficiency or infection with opportunistic enteropathogens. rhesus macaques infected with simian immunodeficiency virus (siv) develop an aids-like illness that frequently includes enteropathy. the development of enteropathy and its association with siv infection in the intestinal tract was examined. by 1 week after infection, siv-infected macrophages and t lymphocytes were detected in gut-associated lym ...	1994	8169404
immune responses induced by prototype vaccines for aids in rhesus monkeys.	a battery of assay systems was used to profile both humoral and cell-mediated immune responses induced by immunization with candidate vaccines consisting of recombinant simian immunodeficiency virus (siv) glycoproteins rgp110 (nondenatured) with saf-m adjuvant (gp110 + saf-m) or rgp140 (denatured) with freund's adjuvant (gp140 + fa). all of the monkeys became infected after intravenous challenge. however, 16 days following infection, viral antigenemia was reduced in both groups of vaccinates com ...	1994	8179961
intrathecal synthesis of igg in simian immunodeficiency virus (siv)-infected rhesus macaques (macaca mulatta).	we examined cerebrospinal fluid (csf) and serum from 25 simian immunodeficiency (siv)-infected rhesus macaques for the presence of siv-specific immunoglobulin g (igg) and for intrathecal synthesis of igg. siv-specific igg was present in csf from almost 50% of the macaques. in approximately half of these animals the siv-specific igg appeared to be derived from serum by leakage across a disrupted blood-brain barrier, whereas in the remaining animals there was evidence of intrathecal igg synthesis. ...	1994	8179966
the "v3" domain is a determinant of simian immunodeficiency virus cell tropism.	thirty-one different mutant forms of simian immunodeficiency virus (sivmac) were created with changes in the region of env corresponding to the v3 domain of hiv-1. sixteen of these mutants had one amino acid change, 12 had two changes, two had three changes, and one had four changes in the sivmac "v3" loop. the ability of the mutant viruses to replicate in cemx174 cells, rhesus monkey peripheral blood mononuclear cells, and rhesus monkey alveolar macrophages was investigated. ten of the mutant v ...	1994	8189506
in vitro susceptibility of macaca nemestrina to human herpesvirus 6: a potential animal model of coinfection with primate immunodeficiency viruses.	human herpesvirus 6 (hhv-6), a lymphotropic herpesvirus, has been suggested as a potential cofactor in the acquired immunodeficiency syndrome (aids). previous studies indicate that hhv-6 has a restricted range of susceptible species. in this study, we tested the in vitro susceptibility to hhv-6 of macaca nemestrina (pig-tailed macaque), a species that has been found to be infectable by human immunodeficiency virus type i in vivo and that develops an aids-like syndrome following simian immunodefi ...	1994	8198870
reduced virus load in rhesus macaques immunized with recombinant gp160 and challenged with simian immunodeficiency virus.	as a safe alternative to inactivated and live-attenuated whole-virus siv vaccines, we have evaluated the potential of sivmac239 gp160 expressed by recombinant vaccinia virus (vsivgp160) and baculovirus (bsivgp160) to protectively immunize rhesus macaques against intravenous (i.v.) infection with pathogenic sivmac isolates. macaques were immunized with live vsivgp160 and/or bsivgp160 protein partially purified from insect cells. the challenge viruses, propagated in rhesus peripheral blood mononuc ...	1994	8198872
titration and characterization of two rhesus-derived sivmac challenge stocks.	simian immunodeficiency virus infection of macaques is a model for human immunodeficiency virus infection of humans. in vivo-titrated stocks of siv are essential for the utilization of this model for vaccine development. the elicitation of anti-human cell antibodies by some vaccines prepared in human cells and the related protective effects of the vaccine produced in human cells suggest a need for new macaque-derived siv stocks. here we describe the titration and characterization of two stocks o ...	1994	8198874
increased replication of simian immunodeficiency virus in cem x174 cells by morphine sulfate.	infection with simian immunodeficiency virus induces cytopathic effects on cem x174 cells in vitro. syncytium formation of siv-infected cem x174 cells was significantly enhanced in the presence of morphine sulfate, with a concomitant increase in the activity of cellular reverse transcriptase and in the expression of siv p27 core antigen. parallel establishment of the viability of the morphine-treated cells indicates that the short-acting opioid protects against cell lysis induced by siv so that ...	1993	8216245
virus isolation and quinolinic acid in primary and chronic simian immunodeficiency virus infection.	in this 2.5-year study of simian immunodeficiency virus (sivsm) infection in rhesus monkeys, quinolinic acid (quin) levels and virus isolation determinations were made in serial cerebrospinal fluid (csf) and blood samples to evaluate the relationship between these parameters over the course of infection.	1993	8216973
different patterns of neuropathological disease in rhesus monkeys infected by simian immunodeficiency virus, and their relation to the humoral immune response.	the brains of 21 rhesus monkeys inoculated with sivmac251 were examined after intervals ranging from 3 to 27 months and compared with five uninoculated controls. eighteen animals became infected and individually exhibited several distinct patterns of disease. nine (50%) had largely intramural leptomeningeal venous infiltrates (lmvi) without multinucleate giant cells (mgc) or foamy macrophages. three (17%) had only mgc lesions, involving the cerebral parenchyma. one had both patterns and five (33 ...	1993	8232754
the human immunodeficiency virus-1 nef gene product: a positive factor for viral infection and replication in primary lymphocytes and macrophages.	considerable controversy and uncertainty have surrounded the biological function of the human immunodeficiency virus (hiv)-1 nef gene product. initial studies suggested that this early, nonstructural viral protein functioned as a negative regulatory factor; thus, it was proposed to play a role in establishing or maintaining viral latency. in contrast, studies in simian immunodeficiency virus (siv)mac-infected rhesus monkeys have suggested that nef is not a negative factor but rather plays a cent ...	1994	8270859
langerhans cells in oral mucosa of rhesus monkeys before and after infection by simian retrovirus-1 and simian immunodeficiency virus.	to study the influence of experimental infection with simian retrovirus-1 and simian immunodeficiency virus on the number and distribution of langerhans cells in oral mucosa of rhesus monkeys, 10 monkeys were intravenously inoculated with simian retrovirus-1, 7 with simian immunodeficiency virus, and 2 were mock-inoculated. biopsies were taken from gingiva and cheek pouch before infection and at 1 (simian immunodeficiency virus group only), 4, and 7 months after infection. langerhans cells were ...	1993	8284080
spermatogenesis and hormone levels in rhesus macaques inoculated with simian immunodeficiency virus.	the presence of sperm in testicular tissue of rhesus macaques that died as a result of infection with simian immunodeficiency virus (siv) was related to age and body weight. depressed testosterone levels were not associated with elevated lh levels. the data suggest that azoospermia in the siv-infected macaques was due to cachexia and not a direct effect of virus on the testis, supporting a similar hypothesis regarding azoospermia in men infected with human immunodeficiency virus.	1993	8289223
severe pulmonary pneumocystosis in simian acquired immunodeficiency syndrome induced by simian immunodeficiency virus: its characterization by the polymerase-chain-reaction method and failure of experimental transmission to immunodeficient animals.	pneumocystis carinii (pc) infection was observed in three of five rhesus monkeys infected with simian immunodeficiency virus (sivmac251). they showed severe symptoms similar to those associated with human acquired immunodeficiency syndrome (aids). histopathology revealed severe pulmonary pneumocystosis in one of three pc-positive monkeys, and anti-pc antibodies were detected in sera from two of the three monkeys. localization of pc organisms in various organs of the monkeys was examined by the p ...	1993	8295897
new advances in vaccine delivery systems.	successful application of the next generation of vaccines will require that protection be induced with a minimal number of administrations, and that a practical approach to inducing immunity at mucosal surfaces be developed. for these reasons, vaccine-containing microspheres were formulated from the biodegradable and biocompatible copolymer poly(dl-lactide-co-glycolide) [dl-plg]. subcutaneous immunization of mice with 1- to 10-microns microspheres containing a toxoid vaccine of staphylococcal en ...	1993	8303306
in vitro and in vivo infection of rhesus monkey microglial cells by simian immunodeficiency virus.	the observation that microglial cells in brain tissue are probably a major target for human immunodeficiency virus (hiv) infection has raised interest in the pathogenic role of this cell population for the development of neuro-aids. since it is very difficult to obtain microglia from normal or diseased human brain we studied microglial cells isolated from fresh brain tissue of uninfected and simian immunodeficiency virus (siv) infected rhesus monkeys (macacca mulatta) in comparison to peripheral ...	1993	8337831
serum inhibitors precede the development of saids.	rhesus macaque monkeys infected with the simian immunodeficiency virus develop a syndrome mimicking aids in humans. we have demonstrated previously that sera from individuals infected with human immunodeficiency virus type 1 inhibit the proliferation of lymphocytes from healthy noninfected subjects and that this phenomenon is associated with the development of clinical aids. we have also shown that sera from monkeys infected with siv also have such inhibitors. in this body of work, we attempted ...	1993	8340901
alterations of thymus cortical epithelium and interdigitating dendritic cells but no increase of thymocyte cell death in the early course of simian immunodeficiency virus infection.	the role of the thymus in the pathogenesis of simian acquired immunodeficiency syndrome was investigated in 18 juvenile rhesus monkeys (macaca mulatta). the thymus was infected from the first week post-sivmac inoculation, but the amount of virus-positive cells was very low (< 1 in 10(4) t cells) as demonstrated by polymerase chain reaction and in situ hybridization. first morphological alteration was a narrowing of the cortex at 12 and 24 wpi. morphometry revealed no increase of pyknotic t cells ...	1993	8362972
protection of monkeys by a split vaccine against sivmac depends upon biological properties of the challenge virus.	to investigate the role of the anti-cellular immune response in the protection of rhesus macaques against infection with the simian immunodeficiency virus sivmac. to determine the biological differences between siv challenge stocks grown either on human t-cell lines or on monkey peripheral blood mononuclear cells (mpbmc).	1993	8363756
viral determinants of simian immunodeficiency virus (siv) virulence in rhesus macaques assessed by using attenuated and pathogenic molecular clones of sivmac.	to identify viral determinants of simian immunodeficiency virus (siv) virulence, two pairs of reciprocal recombinants constructed from a pathogenic (sivmac239) and a nonpathogenic (sivmac1a11) molecular clone of siv were tested in rhesus macaques. a large 6.2-kb fragment containing gag, pol, env, and the regulatory genes from each of the cloned (parental) viruses was exchanged to produce one pair of recombinant viruses (designated sivmac1a11/239gag-env/1a11 and sivmac239/1a11gag-env/239 to indic ...	1993	8371353
evidence of horizontal transmission of pneumocystis carinii pneumonia in simian immunodeficiency virus-infected rhesus macaques.	this retrospective study used sensitive immunohistochemical methods to detect pneumocystis carinii infections in fixed lung tissues collected from 107 simian immunodeficiency virus (siv)-infected and 10 noninfected rhesus macaques during a 4-year period. p. carinii were detected in 51% of 85 terminally ill siv-infected macaques but in only 2 of 22 macaques killed at earlier stages of siv infection. p. carinii were not detected in any siv-infected macaques held in isolators or in uninfected contr ...	1993	8376830
differences in the b and t cell immune response to the envelope glycoprotein 130 (gp130) of the macaque strain of simian immunodeficiency virus (sivmac), induced by immunization of rhesus macaques with virus-derived or vaccinia virus-expressed gp130.	rhesus macaques were immunized with purified virus-derived simian immunodeficiency virus of macaques (sivmac) 251/32h glycoprotein 130 (gp130) or primed with recombinant vaccinia virus (vv) expressing the env gene of the sivmac bk28 clone and boosted subsequently with virus-derived gp130. high antibody titres of at least 10(4) against recombinant gp140 were induced with both vaccines. analysis of the antibody specificity with a peptide elisa revealed that different linear epitopes were recognize ...	1993	8376957
importance of vpr for infection of rhesus monkeys with simian immunodeficiency virus.	the importance of the vpr gene for simian immunodeficiency virus (siv) replication, persistence, and disease progression was examined by using the infectious pathogenic molecular clone called sivmac239. the atg start codon of the vpr gene was converted to ttg by site-specific mutagenesis. the constructed vpr- mutant virus is identical with the parental sivmac239/nef-stop virus with the exception of this one nucleotide. these viruses replicated with similar kinetics and to similar extents in rhes ...	1993	8380472
immunization with lentivirus-like particles elicits a potent siv-specific recall cytotoxic t-lymphocyte response in rhesus monkeys.	an effective acquired immunodeficiency syndrome (aids) vaccine should be capable of eliciting human immunodeficiency virus (hiv)-specific cytotoxic t-lymphocyte (ctl) responses. we have explored the use of lentivirus-like particles produced in mammalian cells infected with a recombinant vaccinia virus to immunize for the induction of ctl in the simian immunodeficiency virus (siv)/rhesus monkey model for aids. siv-like particles in a threonyl-mdp-based adjuvant did not elicit a high frequency of ...	1993	8384466
analysis of the rhesus cytomegalovirus immediate-early gene promoter.	a cytomegalovirus (cmv) isolate has been recovered from a rhesus macaque (macaca mulatta) experimentally infected with simian immunodeficiency virus. the full-length immediate-early gene (ie) was cloned from a genomic library of this primary rhesus cmv isolate (rhcmv) using the african green monkey (agm) cmv ie gene as probe. the promoter region and the first non-coding exon of the rhcmv ie gene have been sequenced. nucleotide sequence comparisons from positions -733 to +625 (relative to the sta ...	1993	8389084
conserved t-cell receptor repertoire in simian immunodeficiency virus-infected rhesus monkeys.	studies to assess the possibility that the hiv may encode a superantigen that plays a role in the depletion of functional cd4+ lymphocytes in the infected individual have yielded discrepant results. the problem in performing conclusive examinations of this issue may be attributed, at least in part, to the difficulty of prospectively studying individuals from before their infection until the time of profound cd4+ lymphocyte loss. to determine whether the aids virus deletes particular subpopulatio ...	1993	8393899
simian immunodeficiency virus-specific cytotoxic t lymphocytes in rhesus monkeys: characterization and vaccine induction.	an effective hiv vaccine should be capable of eliciting virus-specific cytotoxic t lymphocytes (ctl). we have characterized the cellular and molecular features of a simian immunodeficiency virus of macaques (sivmac) gag-specific ctl response in rhesus monkeys. we have shown that sivmac-infected rhesus monkeys expressing the major histocompatibility complex (mhc) class i molecule mamu-a*01 develop a sivmac gag-specific ctl response which recognizes a 9 amino acid fragment of the gag protein in as ...	1993	8394161
a simple method to distinguish between simian immunodeficiency virus isolates by restriction analysis of pcr products.	a simple method to distinguish between simian immunodeficiency virus (siv) isolates of experimentally infected rhesus macaques is reported. peripheral blood mononuclear cells (pbmc) were prepared from a rhesus macaque infected with sivstm isolated originally from a stump-tailed macaque, or from a rhesus monkey infected with sivsm from a sooty mangabey monkey. pbmc were cocultivated with cem x 174 cells and a region of the siv envelope (env) gene was amplified by the polymerase chain reaction (pc ...	1993	8397819
analysis of simian immunodeficiency virus sequence variation in tissues of rhesus macaques with simian aids.	one rhesus macaque displayed severe encephalomyelitis and another displayed severe enterocolitis following infection with molecularly cloned simian immunodeficiency virus (siv) strain sivmac239. little or no free anti-siv antibody developed in these two macaques, and they died relatively quickly (4 to 6 months) after infection. manifestation of the tissue-specific disease in these macaques was associated with the emergence of variants with high replicative capacity for macrophages and primary in ...	1993	8411355
immune response of rhesus macaques to recombinant simian immunodeficiency virus gp130 does not protect from challenge infection.	simian immunodeficiency virus (siv) infection of rhesus macaques is a model for human immunodeficiency virus (hiv) infection in humans. inactivated and modified live whole-virus vaccines have provided limited protective immunity against siv in rhesus macaques. because of safety concerns in the use of inactivated and live whole-virus vaccines, we evaluated the protective immunity of vaccinia virus recombinants expressing the surface glycoprotein (gp130) of sivmac and subunit preparations of gp130 ...	1993	8416384
simian immunodeficiency virus infection via amniotic fluid: a model to study fetal immunopathogenesis and prophylaxis.	the rising prevalence of infection with the human immunodeficiency virus type 1 (hiv-1) in young women will increase the number of infected children worldwide. because hiv-1 seems to be transmitted mostly intrapartum, fetal infection probably occurs mainly via skin or mucous membrane exposure. a model for this route of fetal infection has been established in primates. after injecting the simian immunodeficiency virus (siv) into amniotic fluid during late gestation, six of seven rhesus monkeys we ...	1993	8433276
simian immunodeficiency virus-specific cd8+ lymphocyte response in acutely infected rhesus monkeys.	to assess the possible role of cytotoxic t lymphocytes (ctls) in containing the spread of human immunodeficiency virus in acutely infected individuals, the temporal evolution of the virus-specific cd8+ lymphocyte response was defined in simian immunodeficiency virus of macaques (sivmac)-infected rhesus monkeys. a brief period of sivmac plasma antigenemia was seen 9 to 16 days following intravenous infection with sivmac, ending as the absolute number of cd8+ peripheral blood lymphocytes (pbls) in ...	1993	8437240
self-limiting infection by int/nef-double mutants of simian immunodeficiency virus.	simian immunodeficiency virus (sivmac) infectious for rhesus monkeys was altered by site-directed mutagenesis of genes influencing in vivo replication and persistence with the long-term goal to develop attenuated lentiviruses with limited replication capacity in vivo. double mutants of sivmac (termed delta-int 1 to 3) were generated by introducing frameshift and deletion mutations into the nef gene and into the pol gene region coding for the integrase protein. delta-int/delta-nef viruses formed ...	1993	8438561
immunization with recombinant bcg-siv elicits siv-specific cytotoxic t lymphocytes in rhesus monkeys.	because the transmission of hiv is likely to occur through cell-associated virus, an effective hiv vaccine should be capable of eliciting hiv-specific ctl. we have employed the simian immunodeficiency virus (siv)/rhesus monkey model to explore the use of the attenuated tuberculosis bacillus, calmette guérin bacillus (bcg), as a vaccine vehicle to elicit aids virus-specific ctl. bcg was engineered to express sivmac gag under the control of hsp70 regulatory sequences. immunization with this rbcg-s ...	1993	8454878
in vivo administration to rhesus monkeys of a cd4-specific monoclonal antibody capable of blocking aids virus replication.	monoclonal antibodies (mabs) specific for cd4 are potent inhibitors of hiv replication in vitro. these agents may be useful prophylactically or in chronic hiv infection if they can be administered without inducing immunosuppression. in the present study, we explored the safety of a cd4-specific murine mab in rhesus monkeys. the mab 5a8, which binds to domain 2 of the cd4 molecule, inhibits aids virus replication noncompetitively at a postvirus binding step. this antibody, which had a similar aff ...	1993	8471310
cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus.	the pattern of expression of gfap immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (siv). blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. strong gfap immunoreactivity was found in astrocytic cells in both uninfected and siv-infected juvenile macaque in the ...	1993	8477048
early phenotypic and functional alterations in lymphocytes from simian immunodeficiency virus infected macaques.	phenotypic and functional changes in lymphocytes from rhesus monkeys (macaca mulatta) were investigated during the first 6 months after infection with siv mac 32h. animals preimmunized with keyhole limpet hemocyanin (klh) were sacrificed 1, 3, 6, 12, and 24 weeks post infection. subset composition and function of lymphocytes from blood, spleen, lymph node and thymus were analysed. in addition to a rapid decline in cd4/cd8 ratios, a massive reduction in cd29+ cd4+ cells was seen in the periphery. ...	1993	8506614
simian immunodeficiency virus infection of the gastrointestinal tract of rhesus macaques. functional, pathological, and morphological changes.	gastrointestinal dysfunction and wasting are frequent complications of human immunodeficiency virus (hiv) infection. nutrient malabsorption, decreased digestive enzymes and hiv transcripts have been documented in jejunal mucosa of hiv-infected patients; however, the pathogenesis of this enteropathy is not understood. rhesus macaques infected with simian immunodeficiency virus (siv) also exhibit diarrhea and weight loss; therefore, we investigated the use of this animal model to study hiv-associa ...	1993	8506946
simian immunodeficiency virus mutants resistant to serum neutralization arise during persistent infection of rhesus monkeys.	we previously described the pattern of sequence variation in gp120 following persistent infection of rhesus monkeys with the pathogenic simian immunodeficiency virus sivmac239 molecular clone (d.p.w. burns and r.c. desrosiers, j. virol. 65:1843, 1991). sequence changes were confined largely to five variable regions (v1 to v5), four of which correspond to human immunodeficiency virus type 1 (hiv-1) gp120 variable regions. remarkably, 182 of 186 nucleotide substitutions that were documented in the ...	1993	8510218
biochemical and immunological characterization of micellar complexes of the envelope glycoprotein of a simian immunodeficiency virus isolated from an african green monkey.	the external envelope glycoprotein gp130 of a simian immunodeficiency virus isolated from an african green monkey (sivagmtyo-7) was purified as micellar complexes. the molecular weight of the gp130 micelles was about 700 k. on electron microscopy, the micelles appeared as spherical particles with a diameter of 15 to 20 nm. such aggregates consisted of about 4 to 5 gp130 monomers. hyperimmune sera raised in rabbits and rhesus monkeys against these gp130 micelles exhibited titers between 10(5) and ...	1993	8514839
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
follicular dendritic cells productively infected with immunodeficiency viruses transmit infection to t cells.	lymphoid organs have been proposed to function as the major reservoir for the human immunodeficiency virus type 1 (hiv-1). within lymphatic tissues germinal centers represent foci of rapidly proliferating b cells governed by the interaction between b and t cells and follicular dendritic cells (fdc). accumulating evidence suggests an important role of fdc in the pathophysiology of the acquired immunodeficiency syndrome. direct proof for the infectibility of fdc with hiv-1 has been lacking until r ...	1995	8577313
protection from hiv-1 envelope-bearing chimeric simian immunodeficiency virus (shiv) in rhesus macaques infected with attenuated siv: consequences of challenge.	to determine whether prior infection with simian immunodeficiency virus (siv)bk28 protects macaques from subsequent exposure to an hiv-1 envelope chimeric siv (shiv). also, to determine the consequences of viral challenge on cd4 numbers and virus load on the current siv infection.	1995	8605046
simian immunodeficiency virus (siv) gp130 oligomers protect rhesus macaques (macaca mulatta) against the infection with sivmac32h grown on t-cells or derived ex vivo.	the efficacy of three sivmac32h gp130 vaccines was compared in rhesus monkeys. three rhesus monkeys were each immunized over a period of 20 weeks with a total of 600 microgram virion-derived gp130 oligomers (o-gp130) mixed with keyhole limpet hemocyanin and emulsified with incomplete freund's adjuvant. three other monkeys were infected with 5 x 10(8) pfu of vaccinia virus wild type (vv-wt) while three additional animals received an equivalent dose of vv expressing the gp130 of sivmac (vv-gp130). ...	1996	8607276
efficient transcription and replication of simian immunodeficiency virus in the absence of nf-kappab and sp1 binding elements.	ten mutants of the simian immunodeficiency virus (siv) sivmac239 bearing deletions (delta) or substitutions (subst) in the nf-kappab and/or sp1 binding elements were created, and the replicative capacities of the mutants were analyzed. all mutants, including one extensively mutagenized strain entirely missing the nf-kappab and four spl binding elements, replicated with wild-type kinetics and to a wild-type level in peripheral blood mononuclear cell cultures in 50 to 100% of the experiments. one ...	1996	8627791
an env gene derived from a primary human immunodeficiency virus type 1 isolate confers high in vivo replicative capacity to a chimeric simian/human immunodeficiency virus in rhesus monkeys.	to explore the roles played by specific human immunodeficiency virus type 1 (hiv-1) genes in determining the in vivo replicative capacity of aids viruses, we have examined the replication kinetics and virus-specific immune responses in rhesus monkeys following infection with two chimeric simian/human immunodeficiency viruses (shivs). these viruses were composed of simian immunodeficiency virus sivmac239 expressing hiv-1 env and the associated auxiliary hiv-1 genes tat, vpu, and rep. virus replic ...	1996	8627800
polymyositis, arthritis, and uveitis in a macaque experimentally infected with human t lymphotropic virus type i.	to establish a simian model of human t lymphotropic virus type i (htlv-i) infection and disease.	1996	8630109
restriction of hiv-1 (subtype b) replication at the entry step in rhesus macaque cells.	human immunodeficiency virus type 1 (hiv-1) is restricted for replication in rhesus macaque cells and does not establish infection in this species. the block to productive infection of macaque peripheral blood mononuclear cells (pbmc) in culture was investigated. a chimeric virus shiv containing hiv-1 tat, rev, and env and all other genes from a simian immunodeficiency virus clone pathogenic in macaques (i.e., sivmec239) replicated efficiently in macaque pbmc. thus, the attachment step, involvin ...	1996	8638416
in vitro t lymphopoiesis of human and rhesus cd34+ progenitor cells.	differentiation of hematopoietic progenitor cells into t lymphocytes generally occurs in the unique environment of the thymus, a feature that has hindered efforts to model this process in the laboratory. we now report that thymic stromal cultures from rhesus macaques can support t-cell differentiation of human or rhesus cd34+ progenitor cells. culture of rhesus or human cd34+ bone marrow-derived cells depleted of cd34+ lymphocytes on rhesus thymic stromal monolayers yielded cd3+cd4+cd8+, cd3+cd4 ...	1996	8639759
vaccination of pregnant macaques protects newborns against mucosal simian immunodeficiency virus infection.	simian immunodeficiency virus (siv) infection of newborn rhesus macaques is a rapid, sensitive animal model of human pediatric aids. newborn macaques were readily infected by uncloned sivmac following oral-conjunctival exposure and had persistently high viremia and rapid development of aids. in contrast, when 3 pregnant macaques were vaccinated against siv, 2 of the newborns that had transplacentally acquired antiviral antibodies were protected against mucosal siv infection at birth. these resul ...	1996	8648204
vaccine protection by a triple deletion mutant of simian immunodeficiency virus.	twelve rhesus monkeys were vaccinated with sivmac316 delta nef (lacking nef sequences), and 12 were vaccinated with sivmac239 delta3 (lacking nef, vpr, and upstream sequences in u3). sivmac316 and sivmac239 differ by only eight amino acids in the envelope; these changes render sivmac316 highly competent for replication in macrophages. seventeen of the animals developed persistent infections with the vaccine viruses. seven of the 24 vaccinated animals, however, developed infections that were appa ...	1996	8648707
patterns of viral replication correlate with outcome in simian immunodeficiency virus (siv)-infected macaques: effect of prior immunization with a trivalent siv vaccine in modified vaccinia virus ankara.	the dynamics of plasma viremia were explored in a group of 12 simian immunodeficiency virus (siv)-infected rhesus macaques (macaca mulatta) that had received prior immunization with either nonrecombinant or trivalent (gag-pol, env) siv-recombinant vaccinia viruses. three distinct patterns of viral replication observed during and following primary viremia accounted for significant differences in survival times. high-level primary plasma viremia with subsequently increasing viremia was associated ...	1996	8648709
simian immunodeficiency virus dna vaccine trial in macaques.	an experimental vaccine consisting of five dna plasmids expressing different combinations and forms of simian immunodeficiency virus-macaque (sivmac) proteins has been evaluated for the ability to protect against a highly pathogenic uncloned sivmac251 challenge. one vaccine plasmid encoded nonreplicating sivmac239 virus particles. the other four plasmids encoded secreted forms of the envelope glycoproteins of two t-cell-tropic relatives (sivmac239 and sivmac251) and one monocyte/macrophage-tropi ...	1996	8648735
the effect of simian immunodeficiency virus infection in vitro and in vivo on the cytokine production of isolated microglia and peripheral macrophages from rhesus monkey.	microglia are the major target for human immunodeficiency virus (hiv) infection within the central nervous system. because only a few cells are productively infected, it has been suggested that an aberrant cytokine production by this cell population may be an indirect mechanism leading to the development of neurological disorders in hiv-infected patients. therefore we decided to study the secretion pattern of several interleukins (il) by microglial cells and peripheral blood macrophages isolated ...	1996	8661383
prolonged infection in rhesus macaques with simian immunodeficiency virus (sivmac239) results in animal-specific and rarely tissue-specific selection of nef variants.	we analyzed the sequence of nef genes from different tissues of three rhesus macaques that had been infected with molecularly cloned sivmac239 for 88 to 92 weeks. comparison of the predicted amino acid sequences revealed that each macaque had selected out specific amino acid substitutions and that most of this variation (70%) was confined to four regions, amino acids 39 to 75, 90 to 105, 153 to 167, and 191 to 217, comprising 36% of the protein. the nef genes in these animals underwent extensive ...	1996	8661405
whole body positron emission tomography imaging of simian immunodeficiency virus-infected rhesus macaques.	pathogenesis of simian immunodeficiency virus (siv) infection in rhesus macaques begins with acute viremia and then progresses to a distributed infection in the solid lymphoid tissues, which is followed by a process of cellular destruction leading to terminal disease and death. blood and tissue specimens show the progress of infection at the cellular level but do not reveal the pattern of infection and host responses occurring throughout the body. the purpose of this investigation was to determi ...	1996	8692831
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