replication and apical budding of hiv-1 in mucous-secreting colonic epithelial cells.the human colonic adenocarcinoma cell line ht29 can be infected with various isolates of human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2). in some cases, the virus was able to perform its complete cycle of replication as demonstrated by the persistent production of mature viral particles in the cell-free culture supernatant. we have cultured ht29 cells chronically infected with the replicative strain hiv1-ndk in a chemically defined serum-free medium. under these conditions, the ce ...19921280683
mannosyl/n-acetyl-beta-d-glucosaminyl binding properties of the envelope glycoprotein of human immunodeficiency virus type 2.we have recently demonstrated that human immunodeficiency virus type 1 (hiv-1) recombinant envelope glycoprotein precursor gp160 (rgp160) behaves as a mannosyl/n-acetylglucosaminyl (glcnac) binding protein. if such a carbohydrate-binding property were of biological relevance it should be shared by other related primate immunodeficiency viruses such as hiv-2. the present study confirms this hypothesis and extends these findings by showing that hiv-2 recombinant gp140 (rgp140) specifically interac ...19921281021
epitopes of human immunodeficiency virus regulatory proteins tat, nef, and rev are expressed in normal human tissue.the expression of regulatory proteins tat, rev, and nef of human immunodeficiency virus type-1 (hiv-1) and tat of hiv-2 was studied in frozen sections of lymph nodes from hiv-1-infected individuals, and various tissues from uninfected persons. in hiv-1-positive lymph nodes, monoclonal antibodies to hiv-1-tat stained solitary cells in the germinal centers and interfollicular zones, and vascular endothelium. staining by an anti-nef monoclonal antibody was restricted to follicular dendritic cells, ...19921279980
mutagenesis of the glu-89 residue in human immunodeficiency virus type 1 (hiv-1) and hiv-2 reverse transcriptases: effects on nucleoside analog resistance.a glu-89-->gly alteration in the human immunodeficiency virus type 1 reverse transcriptase (rt) was previously shown to result in resistance to several dideoxynucleoside analogs and to phosphonoformic acid (pfa; foscarnet). this residue was altered to ala, val, ser, thr, gln, asp, asn, or lys, and the ddgtp and pfa sensitivities of the mutant rts were measured. replacements with ala, gly, val, and thr led to resistance to inhibition by ddgtp, while mutants with amino acid ser, gln, asn, asp, or ...19921279207
production of monoclonal antibodies to human immunodeficiency virus type-2.the rod strain of the human immunodeficiency virus type 2 (hiv-2) was used to produce monoclonal antibodies. virus grown in cem cells was partially purified by ultracentrifugation and solubilized in a buffer containing triton x-100. balb/c mice were inoculated intraperitoneally with 50 micrograms of solubilized virus preparations mixed 1:1 with complete freund's adjuvant. animals were boosted on day 28 and sacrificed on day 31. spleen cells from the immunized animals were fused with sp20/ag 14 m ...19921282263
cd4 activation of hiv fusion.the primary cellular receptor for the human immunodeficiency viruses type 1 (hiv-1) and type 2 (hiv-2) is the cd4 antigen. hiv infection of cd4+ cells is initiated by binding of the virus to the cell surface, via a high affinity interaction between cd4 and the hiv outer envelope glycoprotein, gp120. the development of model systems using soluble recombinant forms of cd4 (scd4) has allowed kinetic and thermodynamic analyses of cd4 binding to gp120, and study of the post-binding events leading to ...19921281202
selective inhibition of human immunodeficiency viruses by racemates and enantiomers of cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine.2',3'-dideoxy-5-fluoro-3'-thiacytidine (ftc) has been shown to be a potent and selective compound against human immunodeficiency virus type 1 in acutely infected primary human lymphocytes. ftc is also active against human immunodeficiency virus type 2, simian immunodeficiency virus, and feline immunodeficiency virus in various cell culture systems, including human monocytes. the antiviral activity can be prevented by 2'-deoxycytidine, but not by other natural nucleosides, suggesting that ftc mus ...19921283296
comparative purification of recombinant hiv-1 and hiv-2 reverse transcriptase: preparation of heterodimeric enzyme devoid of unprocessed gene product.a procedure for producing and purifying recombinant hiv-1 and hiv-2 reverse transcriptase (rt) is described. these enzymes are produced by escherichia coli-transformed with a plasmid containing the gene encoding for either the human immunodeficiency virus type 1 (hiv-1) or hiv-2 rt protein. both proteins are partially processed by host cell proteases giving rise to a mixture of heterodimeric and nonheterodimeric products, which are subsequently resolved to near homogeneity by chromatography on p ...19921283095
[the characteristics of the hiv isolated from hiv-infected persons and aids patients on the territory of the cis].hiv strains were isolated from hiv-infected patients and aids patients in cis. a total of 81 hiv isolates were obtained. the isolates were identified by using immunofluorescence and enzyme immunoassay, by determining the activity of reverse transcriptase, immunoblot, electron microscopy, polymerase chain reaction. of the 81 isolates 79 were hiv-1 and 2 hiv-2. the strains differed in their infectivity, the kinetics of virus antigen accumulation, and the spectrum of susceptible cell lines. the vir ...19921284212
potential anti-aids naphthalenesulfonic acid derivatives. synthesis and inhibition of hiv-1 induced cytopathogenesis and hiv-1 and hiv-2 reverse transcriptase activities.several naphthalenedi- and trisulfonic acids have been synthesized and evaluated for inhibitory potential against cytopathogenesis and purified recombinant human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) reverse transcriptase (rt). the most potent derivative that emerged from the anti-rt study was a small molecule 6 (mw = 840), a dipalmitoylated derivative of 2,7-naphthalenedisulfonic acid. analog 6 demonstrated 50% inhibitory concentration (ic50) values of 2.42 and 0.86 microm fo ...19921282569
significant anti-hiv activity of new modified polyanionic polymers in vitro.the anti-hiv activities of two new polyanionic polymers (am 242 and am 612) were investigated in cell culture-based and biochemical antiviral assays. these compounds inhibited the reverse transcriptases from hiv-1 and hiv-2, using enzyme purified from virions and either a ribosomal rna or gapped duplex dna as the template. with the ribosomal rna template, am 242 and am 612 had id50 values of 1.1 and 0.10 micrograms/ml against the hiv-1 reverse transcriptase. in vitro cell based assays determined ...19921294618
mechanism of anti-human immunodeficiency virus action of polyoxometalates, a class of broad-spectrum antiviral agents.various polyoxometalates proved inhibitory to the replication of a number of enveloped dna and rna viruses, i.e., herpesviruses (herpes simplex and cytomegalo), togaviruses (sindbis), paramyxoviruses (respiratory syncytial), rhabdoviruses (vesicular stomatitis), arenaviruses (junin and tacaribe), and retroviruses [human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2), simian immunodeficiency virus, and murine sarcoma virus]. the most potent compounds, i.e., jm1590 [k13[ce(siw11o39)2]. 2 ...19921282664
hiv-1 and hiv-2 infection in children in abidjan, côte d'ivoire.we conducted a study of 1,003 well and hospitalized children, birth to 5 years old, in abidjan, côte d'ivoire, to determine the prevalence of hiv-1 and hiv-2 infection, evaluate risk factors for infection, and describe associated clinical characteristics. the overall seroprevalence was significantly higher for children in the hospital (10.8%) than for those attending the clinic (3.6%). hiv-1 was the predominant virus in both populations, comprising 87% (hospital) and 77% (clinic) of the seroreac ...19921313865
a comparison of regulatory features in primate lentiviruses.historically, research into the regulation of gene expression in primate lentiviruses has focused on human immunodeficiency virus type 1 (hiv-1), the primary cause of acquired immunodeficiency syndrome (aids) in humans. the increasing emergence of hiv-2 as a human pathogen, and the importance of the various simian immunodeficiency viruses (siv) as models for the treatment and prevention of hiv-1-induced disease, suggest that an understanding of gene regulation in these related viruses will becom ...19921315144
evidence for a lentiviral etiology in an epizootic of immune deficiency and lymphoma in stump-tailed macaques (macaca arctoides).a retrospective study determined that an epizootic of immune suppression and lymphoma in stump-tailed macaques (macaca arctoides) that began in 1976 was associated with a horizontally spread lentivirus infection. this conclusion was based on serology, epidemiology, pathology, and virus isolation. the lesions found in the stump-tailed macaques were more compatible with lesions seen in siv-infected rhesus than those seen in rhesus macaques infected with type d retroviruses. a lentivirus, isolated ...19921318381
[hepatitis c virus antibodies in patients and the normal population].with regard to the controversial issue of a reduction of transfusion-associated infections by non-remunerated donations, epidemiological data on the prevalence of hiv-1, hiv-2 and hepatitis c virus (hcv) are of particular interest in our country. we investigated four sample categories: (1) healthy employees and workers from hamburg; (2) hemodialysis patients; (3) hemato-oncological patients, and (4) blood donors, and tried to differentiate between the three disputed vectors of community-acquired ...19921284688
[study of antigenic structure of hiv-1 protein p24 using monoclonal antibodies].during the experiments 4 murine and 3 rat hybridomas producing monoclonal antibodies (mab) against the protein p24 of human immunodeficiency virus type 1 (hiv-1) have been obtained. using the immunoblotting technique, it was established that all the species of mab reacted with the same viral proteins which are derivatives of gag gene--p24 and p55. the properties of mab have been studied in competitive binding. their ability of binding to different fragments of the gag protein produced by the rec ...19921283723
monitoring for hiv-1, hiv-2, htlv-i sero-progression and sero-conversion in a population at risk in east africa.thirty-three individuals from east africa, at risk for acquiring sexually transmitted infections, were selected to be monitored over a five month period for evidence of sero-progression and/or sero-conversion for human immunodeficiency virus type-1 and type-2 (hiv-1, hiv-2), and human t cell leukemia virus type-1 (htlv-i). initially, all sera were reactive by at least one retroviral screening assay, but most produced negative or indeterminate results by western blot assays. five months after the ...19921294680
prevalence of markers for human immunodeficiency virus types 1 and 2, human t-lymphotropic virus type i, cytomegalovirus, and hepatitis b and c virus in multiply transfused thalassemia patients. the french study group on thalassaemia.the prevalence of markers for human immunodeficiency virus types 1 and 2 (hiv-1, hiv-2), human t-lymphotropic virus type i (htlv-i), hepatitis b virus (hbv) and hepatitis c virus (hcv), and cytomegalovirus (cmv) was evaluated in a population of 305 multiply transfused thalassemia patients in belgium, france, and italy (sicily). no patients were found positive for hiv-2 antibodies. two french patients were seropositive for hiv-1, having been infected before systematic blood screening. antibodies ...19921323885
seroreactivity to human t cell leukemia/lymphoma virus type 1 and related retroviruses in multiple sclerosis patients from denmark and the faroes.a total of 40 multiple sclerosis (ms) patients from denmark and 10 from the faroes were examined for antibodies with affinity to human t cell leukemia/lymphoma virus type 1 (htlv-i) and human immunodeficiency virus type 1 and 2 (hiv-1 and hiv-2). using elisa, ms patients and a group of healthy controls did not differ significantly in their reactivities to htlv-i. however, elevated reactivities were recorded with 5 ms sera, whereas only 2 of the sera from the controls produced highly values. ten ...19921325731
testing for antibodies to human immunodeficiency virus type 2 in the united states.the food and drug administration (fda) has recommended that all donated blood be screened for antibodies to human immunodeficiency virus type 2 (hiv-2) beginning no later than june 1, 1992. this article provides cdc recommendations for the diagnosis of hiv-1 and hiv-2 infections in persons being tested in settings other than blood centers and cdc/fda guidelines for serologic testing with combination hiv-1/hiv-2 screening enzyme immunoassays (eias). epidemiologic data indicate that the prevalence ...19921324395
the mannose-specific plant lectins from cymbidium hybrid and epipactis helleborine and the (n-acetylglucosamine)n-specific plant lectin from urtica dioica are potent and selective inhibitors of human immunodeficiency virus and cytomegalovirus replication in vitro.a series of four mannose(man)-, three n-acetylglucosamine (glcnac)n-, ten n-acetylgalactosamine/galactose(galnac/gal)-, one 5-acetylneuraminic acid (alpha-2,3-gal/galnac)- and one 5-acetylneuroaminic acid(alpha-2,6-gal/gal-nac)-specific plant agglutinins were evaluated for their antiviral activity in vitro. the mannose-specific lectins from the orchid species cymbidium hybrid (ca), epipactis helleborine (eha) and listera ovata (loa) were highly inhibitory to human immunodeficiency virus type 1 ( ...19921329650
mechanism of inhibition of the retroviral protease by a rous sarcoma virus peptide substrate representing the cleavage site between the gag p2 and p10 proteins.the activity of the avian myeloblastosis virus (amv) or the human immunodeficiency virus type 1 (hiv-1) protease on peptide substrates which represent cleavage sites found in the gag and gag-pol polyproteins of rous sarcoma virus (rsv) and hiv-1 has been analyzed. each protease efficiently processed cleavage site substrates found in their cognate polyprotein precursors. additionally, in some instances heterologous activity was detected. the catalytic efficiency of the rsv protease on cognate sub ...19921331099
computer analysis of the amino acid sequences in gp41 of apathogenic african green monkey (agm) virus, less pathogenic hiv-2 and highly pathogenic siv and hiv-1 lentiviruses.the bestfit computer program was used to compare the amino acid sequence of the gp160 envelope glycoprotein of an apathogenic agm and the pathogenic sivagm monkey lentiviruses. it was found that the gp120 envelope glycoproteins of these viruses resembled each other in their functional domains. however, an insert of 40 amino acids was found in the gp41 envelope glycoproteins of the pathogenic sivagm virus in the amino acid sequence between the membrane anchoring sequence and the carboxyterminus. ...19921335629
susceptibility of human monoclonal antibody-producing b cell lines to infection by human immunodeficiency immortalized b cell clones, five of which secreted specific human monoclonal antibodies (mabs) against hepatitis b, tetanus toxoid, and rhesus d antigens, were evaluated for their susceptibility to infection by human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2). infection was confirmed in three human mab-producing lines by detection of infectious virus and p24 antigen in culture supernates, by immunofluorescence, and by detection of viral dna in cells by polymerase chain reaction ...19921335786
side-chain derivatives of biologically active nucleosides. 1. side-chain analogs of 3'-azido-3'-deoxythymidine (azt).starting from 3-o-mesyl-1,2-o-isopropylidene-alpha-d-allofuranose (9) the anomeric mixtures of the requisite carbohydrates 1,2-di-o-acetyl-6-o-benzoyl-5-deoxy-3-o-mesyl-d-allofuranoses++ + 17a alpha/beta, 1,2-di-o-acetyl-5,6-di-o-benzoyl-3-o-mesyl-d-allofuranoses 17b alpha/beta, and 1,2-di-o-acetyl-5,6-di-o-benzoyl-3-o-mesyl-l-talofuranoses 17c alpha/beta were synthesized. 1,2-di-o-acetyl-5-o-benzoyl-6-deoxy-3-o-mesyl-d-allofuranoses++ + 17d alpha/beta and the corresponding l-talofuranoses 17e a ...19921323681
synthetic "interface" peptides alter dimeric assembly of the hiv 1 and 2 proteases.retroviral proteases are obligate homodimers and play an essential role in the viral life cycle. dissociation of dimers or prevention of their assembly may inactivate these enzymes and prevent viral maturation. a salient structural feature of these enzymes is an extended interface composed of interdigitating n- and c-terminal residues of both monomers, which form a four-stranded beta-sheet. peptides mimicking one beta-strand (residues 95-99), or two beta-strands (residues 1-5 plus 95-99 or 95-99 ...19921338945
comparison of indirect immunofluorescence and membrane fluorescence assays for the differentiation of antibodies to human immunodeficiency virus types 1 and 2.serum samples from 20 human immunodeficiency virus type 1 (hiv-1)- and 30 hiv-2-infected and 7 dually infected individuals were reacted by using the indirect immunofluorescence assay (ifa) and membrane fluorescence assay in order to determine whether these methods were useful for typing hiv-1 and hiv-2 antibodies. although 41 of 50 (82%) of the hiv-1- and hiv-2-positive specimens cross-reacted to some extent with the heterologous antigen in the ifa, the antigen with the higher titer correlated c ...19921328285
influence of carbohydrate moieties on the immunogenicity of human immunodeficiency virus type 1 recombinant gp160.the role of carbohydrates in the immunogenicity of human immunodeficiency virus type 1 (hiv-1) glycoproteins (gp160 and gp120) remains poorly understood. we have analyzed the specificity and neutralizing capacity of antibodies raised against native gp160 or against gp160 deglycosylated by either endo f-n glycanase, neuraminidase, or alpha-mannosidase. rabbits immunized with these immunogens produced antibodies that recognized recombinant gp160 (rgp160) from hiv-1 in a radioimmunoassay and in an ...19921347797
identification and evaluation of new primer sets for the detection of lentivirus proviral dna.we have developed sets of degenerate oligonucleotides designed to detect pol gene sequences from any member of the lentivirus subfamily when used as primers in amplification techniques such as the polymerase chain reaction (pcr). this pan-lentivirus-specific primer set (plsps) consists of primers, lv1, lv2, and lv3, based on conserved regions common to lentiviruses only. our protocol is based on primary amplification with lv1 and lv2 followed by secondary amplification with a nested primer set b ...19921337258
solid phase synthesis of the proteinase of bovine leukemia virus. comparison of its specificity to that of hiv-2 proteinase.the 126-residue proteinase (pr) of bovine leukemia virus (blv) was synthesized by solid-phase peptide synthesis and its activity was shown using various oligopeptide substrates representing cleavage sites in blv, human t-cell leukemia virus type 1 (htlv-1), murine leukemia virus (mulv) and human immunodeficiency virus type 1 (hiv-1). the specificity of the blv pr was also compared to that of chemically synthesized human immunodeficiency virus type 2 (hiv-2) pr. many of the peptides were cleaved ...19921325379
virological and polymerase chain reaction studies of hiv-1/hiv-2 dual infection in côte d'ivoire.dual serological reactivity to the human immunodeficiency virus (hiv) types 1 and 2 is common in côte d'ivoire. to assess whether dual infection is the reason for dual seropositivity we sought hiv-1 and hiv-2 proviral dna in primary uncultured peripheral blood mononuclear cells from selected seropositive patients in côte d'ivoire with the polymerase chain reaction (pcr). pcr on primary lymphocytes in 36 dually seropositive samples revealed the presence of both hiv-1 and hiv-2 proviral dna in 12 ...19921353807
sulfated alkyl oligosaccharides with potent inhibitory effects on human immunodeficiency virus infection.compounds with medium relative molecular masses active against human immunodeficiency virus (hiv) were synthesized. sulfated alkyl oligosaccharides such as sulfated octadecyl maltohexaoside, sulfated dodecyl laminaripentaoside and sulfated dodecyl laminari-oligomer caused 50% inhibition of virus infection in the ec50 range of 0.4-0.7 microgram/ml in vitro using the mt-4 cell line and hiv-1htlv-iiib virus isolate, though sulfated oligosaccharides without alkyl groups showed low anti-hiv activitie ...19921351727
prevalence of hiv-1 and hiv-2 mixed infections in côte d'ivoire.we have investigated the cause of dual serological reactivity to human immunodeficiency virus (hiv) types 1 and 2, a common occurrence in west africa. serum specimens from 111 individuals from côte d'ivoire classified by commercial western blot as hiv-1 (n = 15), hiv-2 (32), and dually reactive (64) were further tested by more specific serological tests (a synthetic peptide enzyme immunoassay [pepti-lav 1/2] and western blots prepared from antigen in which oligomeric forms of the transmembrane p ...19921353806
human immunodeficiency virus (hiv) type 1 can superinfect hiv-2-infected cells: pseudotype virions produced with expanded cellular host studies on viral interference, cloned t-cell lines chronically infected with human immunodeficiency virus (hiv) type 1 or hiv-2 were inoculated with several strains of these two aids retrovirus subtypes. hiv-2uc1-infected cells, which still express the cd4 receptor, could be superinfected with a variety of hiv-1 and hiv-2 strains. this event was accompanied by cytopathic effects in the cells and production of pseudotype virions with an expanded cellular host range. hiv-1- or hiv-2-infected cl ...19921346069
[the spread of human immunodeficiency virus infection (hiv-1/hiv-2) and of hepatitis b and c in non-drug-addicted prostitutes. extremadura].the proportion of cases of aids in extremadura, in which sexual transmission has existed, is comparatively lower than the national one. the possibilities of the infection introduction in the general population may increase the relative importance of this way of transmission in the future. penetration of hiv is unknown in prostitutes living and working in the autonomous community of extremadura, as a collective associated to virus sexual transmission and to other socio-cultural risk factors invol ...19921366224
hiv infection at outcome of pregnancy in the paris area, france.the prevalence of hiv infection in women at end of pregnancy, irrespective of outcome, was determined in a comprehensive survey of both women and medical centres during successive 4-week periods in four areas of the paris region, france. blood samples were tested anonymously for antibodies to human immunodeficiency virus (hiv)-1 and hiv-2. of the 11,593 blood samples 0.40% (95% confidence interval [ci] 0.28-0.51) were positive for hiv-1 and 0.02% (95% binomial interval [bi] 0.002-0.065) for hiv- ...19921355808
detection of human immunodeficiency virus type 2 in brain tissue.infection due to human immunodeficiency virus (hiv) type 2 is believed to cause a clinical picture similar to that of hiv-1, although extensive data are not available. in 2 patients with west african exposure and neurologic symptoms, hiv-2 was detected in the central nervous system using dna and rna polymerase chain reaction, in situ hybridization, and immunohistology. in the first patient, the neurologic disease was most likely due to productive infection with hiv-2. in the second, a combinatio ...19921356128
prevention of hiv-2 and siv infections in cynomolgus macaques by prophylactic treatment with 3'-fluorothymidine.the aim of this study was to determine the usefulness of human immunodeficiency virus type 2 (hiv-2) for in vivo evaluation of antiviral drugs in monkeys and to study if prophylactic treatment with 3'-fluorothymidine (flt) could prevent infection against a low challenge dose of hiv-2 or simian immunodeficiency virus (siv). protection against infection was assessed by virus isolation and polymerase chain reaction (pcr) on monkey peripheral blood mononuclear cells (pbmc) as well as by antibody and ...19921355658
role of mycoplasma infection in the cytopathic effect induced by human immunodeficiency virus type 1 in infected cell addition to previously reported tetracycline analogs, other antibiotics known for antimycoplasmal activities inhibited the cytopathic effect in cem cl13 cells infected with human immunodeficiency virus type 1 (hiv-1) or hiv-2 but were unable to block virus replication. a contaminating mycoplasma was isolated from our cem cl13 cells and identified as a strain of mycoplasma fermentans. following infection of lymphoblastoid (cem) or promonocytic (u937 and thp1) cell lines with hiv-1, cytopathic ...19921371767
the effects of cysteine mutations on the reverse transcriptases of human immunodeficiency virus types 1 and 2.chemical modification of hiv-1 and hiv-2 (human immunodeficiency virus, types 1 and 2) reverse transcriptases (rt) with three thiol reactive compounds selectively inhibits the rnase h function of the enzyme. hiv-1 rt has 2 cysteines (at positions 38 and 280); hiv-2 rt has 3 (38, 280, 445). both of the cysteines in hiv-1 rt are in the polymerase domain. to investigate the role of the cysteines in the structure and function of the hiv rts, we have converted each cysteine to serine and made combina ...19921370463
detection of viral surface antigens on hiv-2ben infected human tumor cell lines by flow cytometry.the human monocytic cell line u-937 clone 2 and two t-cell lines cem and molt-4 clone 8 were infected with hiv-2ben, a recent isolate of hiv-2. infection and subsequent antigen expression on the cell surface was monitored by flow cytometry using a rabbit-anti-serum against tween-ether-treated hiv-2ben and a fluorescein-isothiocyanate-conjugated igg against rabbit-igg. the sensitivity of the three cell lines to infection with hiv-2ben correlated with the percentages of cd4-expressing cells but no ...19921374306
the effect of bioreactor configuration on production of hiv and cell-virus an attempt to establish a bioreactor system for generation of hiv that is practicable, efficient, biologically contained, and capable of scale up, the production of two strains of this virus was examined in suspension culture and the 'porosphere' fixed bed system. hiv 1 and hiv 2 were grown successfully in both these types of reactor. the porosphere reactor theoretically appears to offer a better environment for hiv production, but evidence for significantly improved yields from this system, ...19901367042
resistance of human immunodeficiency virus type 1 reverse transcriptase to tibo derivatives induced by site-directed mutagenesis.the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is the target enzyme for the tetrahydro-imidazo[4,5,1-jk][1,4]- benzodiazepin-2(1h)one and thione (tibo) derivatives, a class of highly potent and selective anti-hiv agents that specifically inhibit hiv-1 but not hiv-2 replication. the amino acid sequence divergence may be held responsible for the differential sensitivity of hiv-1 rt and hiv-2 rt to the tibo derivatives. using site-directed mutagenesis, we have introdu ...19921374986
cross-neutralization of human immunodeficiency virus type 1 and 2 and simian immunodeficiency virus contrast to infrequent and low-titer cross-neutralization of human immunodeficiency virus type 1 (hiv-1) isolates by hiv-2- and simian immunodeficiency virus (siv)-positive sera, extensive cross-neutralization of hiv-2nih-z, sivmac251, and sivagm208k occurs with high titer, suggesting conservation of epitopes and mechanism(s) of neutralization. the v3 regions of hiv-2 and siv isolates, minimally related to the hiv-1 homolog, share significant sequence homology and are immunogenic in monkeys a ...19921374810
identification of b-cell antigenic sites on hiv-2 gp125.synthetic peptides were used to identify continuous antigenic sites on the external envelope glycoprotein gp125 of human immunodeficiency virus (hiv)-2. initially, seven hiv-2-positive human serum samples were screened with 172 sequential nonapeptides containing a six-amino-acid overlap. this represents the entire gp125 molecule of hiv-2isy. the antibody reactivity was found to be mainly restricted to 14 regions within gp125. following these results, 33 longer peptides, 15-24 amino acids in leng ...19921370692
2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino-1'',2''- oxathiole-2'',2'-dioxide)pyrimidine (tsao) nucleoside analogues: highlyselective inhibitors of human immunodeficiency virus type 1 that are targeted at the viral reverse transcriptase.a series of pyrimidine nucleoside analogues containing [2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide)]-beta-d-ribofuranose as the pentose were found to inhibit human immunodeficiency virus type 1 [hiv-1(iiib)] replication at a concentration of 0.06-0.8 microm but were not cytotoxic at a 1000- to 10,000-fold higher concentration. these nucleoside derivatives were also effective against various other hiv-1 strains, including those resistant to 3' ...19921374900
pcr amplification of large genomic fragments from human and simian immunodeficiency virus infected cell lines.polymerase chain reaction (pcr) has been used to amplify the large fragments from viral genomic dna of siv from wild caught, asymptomatic erythrocebus monkeys from western africa (senegal) and also from hiv-2 infected cell lines. by using consensus primer sequences from highly conserved stretches of gag, pol and env genes, two halves of the viral genome of hiv-2 and siv (isolated from west african erythrocebus monkeys) have amplified by pcr. one half spans 5200 bp from within the u3 region of th ...19921375701
kinetics of inhibition of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase by the novel hiv-1-specific nucleoside analogue [2',5'-bis-o-(tert-butyldimethylsilyl)-beta-d-ribofuranosyl]-3'-spiro-5 "- (4"-amino-1",2"-oxathiole-2",2"-dioxide)thymine (tsao-t).[2',5'-bis-o-(tert-butyldimethylsilyl)-beta-d-ribofuranosyl]-3'-spiro- 5"-(4"-amino-1",2"-oxathiole-2", 2"-dioxide)thymine (tsao-t) is a representative of a novel class of nucleoside analogues that are endowed with a potent and specific activity against human immunodeficiency virus (hiv) type 1 and are targeted at the hiv-1 reverse transcriptase (rt). inhibition of hiv-1 rt by tsao-t was reversible and noncompetitive with respect to dgtp as the substrate and poly(c).oligo(dg) as the template/pri ...19921376314
novel non-nucleoside inhibitors of hiv-1 reverse transcriptase. 2. tricyclic pyridobenzoxazepinones and dibenzoxazepinones.dibenz[b,f][1,4]oxazepin-11(10h)-ones (iii), pyrido[2,3-b][1,4]benzoxazepin-6(5h)-ones (iv), and pyrido[2,3-b]- [1,5]benzoxazepin-5(6h)-ones (v) were found to inhibit human immunodeficiency virus type 1 reverse transcriptase with ic50 values as low as 19 nm. a-ring substitution has a profound effect on activity, with appropriate substituents at the positions ortho and para to the lactam nitrogen providing dramatically enhanced potency. substitution in the c-ring is generally neutral or detriment ...19921375293
fidelity of the reverse transcriptase of human immunodeficiency virus type 2.the relatively low fidelity of human immunodeficiency virus type 1 reverse transcriptase (hiv-1 rt) was implicated as a major factor that contributes to the genetic variability of the virus. extension of mismatched 3' termini of the primer dna was shown to be a major determinant of the infidelity of hiv-1 rt. human immunodeficiency virus type 2 (hiv-2) also shows extensive genetic variations. therefore, we have analyzed the fidelity of the dna-dependent dna polymerase activity of hiv-2 rt and co ...19921378791
detection of a human intracisternal retroviral particle associated with cd4+ t-cell deficiency.a number of non-human-immunodeficiency-virus (hiv) type 1 disorders are associated with cd4+ t-cell deficiency and dysfunction. however, the etiopathogenesis of cd4+ t-cell immunodeficiency in these disease states remains unclear. human intracisternal retroviral (hicrv) particles were detected in a lymphoblastoid cell line exposed to mononuclear cells from a patient with severe cd4+ t-cell deficiency without risk factors for hiv infection. ultrastructurally, the hicrv is distinct from hiv-1, hiv ...19921380169
(-)-2'-deoxy-3'-thiacytidine is a potent, highly selective inhibitor of human immunodeficiency virus type 1 and type 2 replication in vitro.the (-)-enantiomer of 2'-deoxy-3'-thiacytidine (3tc) was found to be a potent and selective inhibitor of human immunodeficiency virus types 1 (hiv-1) and 2 (hiv-2) in vitro. we determined its antiviral activity against a number of laboratory strains of hiv-1 and hiv-2 in a range of cd4-bearing lymphocyte cell lines (mean 50% inhibitory concentration [ic50] range, 4 nm to 0.67 microm). 3tc was also active against a range of hiv-1 strains in peripheral blood lymphocytes (mean ic50 range, 2.5 to 90 ...19921380229
identification of a neutralizing domain in the external envelope glycoprotein of simian immunodeficiency virus.two murine monoclonal antibodies (mabs), designated matg2014 and matg2033, were generated. they are reactive with the external envelope glycoprotein gp130 of the simian immunodeficiency virus of macaque monkey (sivmac251), and display a cell-free virus neutralizing activity in vitro. in addition, matg2014 cross-reacts with hiv-2rod gp140. epitope mapping of these mabs was performed by screening and sivmac peptide library expressed in yeast and confirmed using synthetic peptides. matg2014 and mat ...19921380263
structure-function relationships of hiv-1 reverse transcriptase determined using monoclonal antibodies.the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is one of the main targets in approaches to the chemotherapy of aids. a detailed knowledge of structure-function relationships of this enzyme is a prerequisite for rational drug design. we have used monoclonal antibodies as tools to identify functionally important regions of the protein. the preparation of 23 murine monoclonal antibodies (mab) against hiv-1 reverse transcriptase and their different effects on the enzym ...19921378837
differential inhibitory effects of tibo derivatives on different strains of simian immunodeficiency virus.recently, several classes of compounds have been shown to be extremely selective inhibitors of human immunodeficiency virus type 1 (hiv-1) replication in vitro. these include the tetrahydro-imidazo[4,5,1-jk][1,4]-benzodiazepin-2(1h)-one and -thione (tibo), 1-(2-hydroxyethoxymethyl)-6-(phenylthio)-thymine (hept), dipyridodiazepinone, pyridinone and bis(heteroaryl)piperazine derivatives. the hallmark of these new antiviral compounds is a specific interaction with reverse transcriptase (rt) of hiv- ...19921378481
identification of the human immunodeficiency virus reverse transcriptase residues that contribute to the activity of diverse nonnucleoside inhibitors.the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is potently inhibited by a structurally diverse group of nonnucleoside compounds. these include pyridinone derivatives, tetrahydroimadazo[4,5,1-j,k][1,4]-benzodiazepin-2(1h)-one and -thione, and bi-rg-587 (nevirapine). the compounds act noncompetitively, by an unknown mechanism, with respect to template-primer and nucleotide substrates. despite a high degree of similarity between the hiv-1 and hiv-2 rts, the hiv-2 enzy ...19921380789
inhibition of human immunodeficiency virus and growth of infected t cells by the immunosuppressive drugs cyclosporin a and fk 506.the effects of the immunosuppressive drugs cyclosporin a and fk 506 were studied on cells chronically infected with human immunodeficiency virus type 1 (hiv-1) as well as on uninfected and newly infected cells. when cells chronically infected with hiv-1 or with hiv-2 were cocultivated with uninfected cells in the presence of cyclosporin a or fk 506 there was a delay in the formation of syncytia and of cytopathic effects. this inhibitory effect was not due to decreased membrane expression of cd4. ...19921381509
subtyping of human immunodeficiency virus isolates with a panel of monoclonal antibodies: identification of conserved and divergent epitopes on p17 and p25 core proteins.we have investigated the feasibility and significance of subtyping of human immunodeficiency virus (hiv) isolates with monoclonal antibodies (mab) raised against the core proteins of hiv. a panel of 37 mab tested for reactivity with hiv1 oligopeptides was used to analyse the antigenic relatedness among 14 hiv isolates which included 12 isolates of hiv1 from different geographical origins and 2 isolates of hiv2. three out of these 37 mab reacted with conserved epitopes expressed by all 14 hiv iso ...19921382219
the calanolides, a novel hiv-inhibitory class of coumarin derivatives from the tropical rainforest tree, calophyllum lanigerum.eight new coumarin compounds (1-8) were isolated by anti-hiv bioassay-guided fractionation of an extract of calophyllum lanigerum. the structures of calanolide a (1), 12-acetoxycalanolide a (2), 12-methoxycalanolide a (3), calanolide b (4), 12-methoxycalanolide b (5), calanolide c (6) and related derivatives 7 and 8 were solved by extensive spectroscopic analyses, particularly hmqc, hmbc, and difference noe nmr experiments. the absolute stereochemistry of calanolide a (1) and calanolide b (4) wa ...19921379639
identification of a gag protein epitope conserved among all four groups of primate immunodeficiency viruses by using monoclonal antibodies.five monoclonal antibodies (mabs) were raised against the gag proteins of simian immunodeficiency virus (siv) from african green monkey (sivagmtyo-7). two mabs reacted with the matrix protein p17 and the other three with the core protein p24. studies on the cross-reactivity of the mabs revealed that the anti-p24 mabs detected an epitope shared by the viruses belonging to the human immunodeficiency virus type 2 (hiv-2)/sivmac group and sivagmtyo-7 and sivagmtyo-5. the anti-p17 mabs recognized an ...19921383399
functional analysis of novel selective mutants of the reverse transcriptase of human immunodeficiency virus type 1.we have generated by site-directed mutagenesis plasmids that induce the synthesis of specific mutants of the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1). these recombinant mutants of hiv-1 rt, designed on the basis of our previous studies of hiv-1 and hiv-2 rts, were analyzed for structure-function relationship by assessing their rna-dependent and dna-dependent dna polymerase as well as the ribonuclease h activities. three groups of mutants were studied. 1) we have ...19921382052
fidelity of the rna-dependent dna synthesis exhibited by the reverse transcriptases of human immunodeficiency virus types 1 and 2 and of murine leukemia virus: mispair extension frequencies.human immunodeficiency viruses type 1 and 2 (hiv-1 and hiv-2, respectively) exhibit extensive genetic variations. it was postulated that much of this genetic variability stems from the low fidelity of the reverse transcription step. both hiv reverse transcriptases (rts) were shown to be particularly error-prone during the in vitro dna-dependent dna synthesis relative to other retroviral rts. extension of mismatched 3'-termini of the primer dna was shown to be a major determinant in the infidelit ...19921382590
human and murine monoclonal antibodies directed against a conserved sequence from gp41 (aa583-599) of human immunodeficiency virus type 1.human spleen cells from an hiv-seropositive donor were immunized in vitro with the aa583-599 peptide conjugated to an heptalysyl core. this sequence was derived from the putatively hiv-immunosuppressive region of hiv1 gp41. the same conjugated peptide was used to immunize mice. one human and one mouse igm monoclonal antibody (mab) directed against the aa583-599 peptide were obtained. the two mab had distinct patterns of reactivity against a panel of 42 peptides with modified sequences. neither o ...19921381515
anti-human immunodeficiency virus activity of a novel synthetic peptide, t22 ([tyr-5,12, lys-7]polyphemusin ii): a possible inhibitor of virus-cell fusion.more than 40 peptides associated with tachyplesin and polyphemusin, which are highly abundant in hemocyte debris of the horseshoe crabs tachypleus tridentatus and limulus polyphemus, were synthesized. among these peptides, we found that a novel compound, which was called t22 ([tyr-5,12, lys-7]polyphemusin ii), strongly inhibited the human immunodeficiency virus type 1 (hiv-1)-induced cytopathic effect and viral antigen expression. its 50% effective concentration was 0.008 micrograms/ml, while it ...19921384424
sulfonic acid polymers as a new class of human immunodeficiency virus inhibitors.four sulfonic acid polymers [poly(4-styrenesulfonic acid)(pss), poly(anetholesulfonic acid)(pas), poly(vinylsulfonic acid)(pvs), poly(2-acrylamido-2-methyl-1-propanesulfonic acid)(pamps)] have been found to inhibit the cytopathicity of hiv-1 and hiv-2 in mt-4 cells at concentrations that are not toxic to the host cells. the sulfonic acid polymers also inhibited syncytium formation in co-cultures of molt-4 cells with hiv-1- or hiv-2-infected hut-78 cells. they also inhibited binding of anti-gp120 ...19921384428
[study of the antigenic structure of human immunodeficiency virus using synthetic peptides].in a search for synthetic peptide antigens fit to detect anti-hiv antibodies, a set of algorithms were used to predict the probable antigenic determinants of gag, pol, env and nef proteins of hiv-1 and hiv-2. over forty peptides were synthesized by the solid-phase method. the reactivity of the peptide antigens was evaluated in elisa on panels of hiv-1/2-positive sera. application of the synthetic peptides for the early hiv diagnostics was examined.19921384509
transient stimulation of granulopoiesis and drastic inhibition of erythropoiesis in hiv-2-infected long-term liquid bone marrow cultures.impaired hematopoiesis is commonly associated with human immunodeficiency virus hiv-1 and hiv-2-related aids. hiv-1 infection of hematopoietic progenitors has been studied, whereas hiv-2 infection of these cells is less well documented. in this work, we studied myeloid and erythroid progenitor production and differentiation in long-term bone marrow (ltbm) cultures after hiv-2 infection. a nonadherent fraction from these cultures containing the hematopoietic progenitors is nonproductively infecte ...19921383491
hiv-2 infections in a rural senegalese a community study in rural senegal, 22 human immunodeficiency virus type-2 (hiv-2) seropositive cases and 64 matched controls were examined clinically and evaluated immunologically. the presence of clinical signs was highly correlated with hiv-2 seropositivity: 9 anti-hiv-2 positive patients and 5 controls presented with clinical signs (odd ratio [or] = 8.2, confidence limits [cl] 2-35). the main symptom associated with hiv-2 seropositivity was a chronic cough (or = 18.5, cl 1.8-899). the pre ...19921402831
inhibition of human immunodeficiency virus infection in human colon epithelial cells by recombinant interferon-gamma.pretreatment of human colon epithelial cells ht29 by recombinant gamma interferon (ifn)-gamma was found to protect the cells from infection with various isolates of human immunodeficiency virus (hiv)-1 and hiv-2, as assessed by co-cultivation with human t lymphoblastoid cells and gene amplification by polymerase chain reaction technique. additionally, ifn-gamma induced a dose-dependent inhibition of hiv-1 and hiv-2 production in chronically infected ht29 cells. in situ hybridization studies demo ...19921396956
discovery and characterization of an hiv-1 tat 5-3335, 7-chloro-5-(2-pyrryl)-3h-1,4-benzo-diazepin-2-(h)-one, has been shown to inhibit gene expression controlled by the human immunodeficiency virus-1 (hiv-1) ltr promoter. the inhibition was specific for the viral transcriptional transactivator tat. the compound did not inhibit the basal activity of the hiv-1 ltr or the activity of promoters not responsive to tat. consistent with its mode of action, ro 5-3335 inhibited hiv-1 replication (ic50 = 0.1-1 microm) by reducing viral rna synthesi ...19921397654
activity and dimerization of human immunodeficiency virus protease as a function of solvent composition and enzyme concentration.the activity of human immunodeficiency virus 1 (hiv-1) protease has been examined as a function of solvent composition, incubation time, and enzyme concentration at 37 degrees c in the ph 4.5-5.5 range. glycerol and dimethyl sulfoxide inhibit the enzyme, while polyethylene glycol and bovine serum albumin activate the enzyme. when incubated at a concentration of 50-200 nm, the activity of the protease decreases irreversibly with an apparent first-order rate constant of 4-9 x 10(-3) min-1. the pre ...19921400318
mutational analysis of the integrase protein of human immunodeficiency virus type 2.purified integrase protein (in) can nick linear viral dna at a specific site near the ends and integrate nicked viral dna into target dna. we have made a series of 43 site-directed point mutants of human immunodeficiency virus type 2 in and assayed purified mutant proteins for the following activities: site-specific cleavage of viral dna (donor cut), integration (strand transfer), and disintegration. in general, the different activities were similarly affected by the mutations. we found three mu ...19921409671
lignified materials as medicinal resources. v. anti-hiv (human immunodeficiency virus) activity of some synthetic lignins.a class of synthetic lignins (dehydrogenation polymers of p-coumaric acid, ferulic acid, and caffeic acid) inhibited cytopathogenicity of hiv-1 and hiv-2 infection. the ratio of cytotoxic to anti-hiv (human immunodeficiency virus) doses depended strongly on conditions during polymer preparation. the activity increased when polymers were treated with reducing agent nabh4, whereas it decreased when treated with oxidizing agent ceric ammonium nitrate. the polymers inhibited expression of hiv-specif ...19921423763
chimeric gag-v3 virus-like particles of human immunodeficiency virus induce virus-neutralizing antibodies.a 41-kda unprocessed human immunodeficiency virus 2 (hiv-2) gag precursor protein that has a deletion of a portion of the viral protease assembles as virus-like particles by budding through the cytoplasmic membrane of recombinant baculovirus-infected insect cells. we have constructed six different combinations of chimeric genes by coupling the truncated hiv-2 gag gene to the neutralizing domain (v3) or the neutralizing and the cd4 binding domains (v3+cd4bd) of gp120 env gene sequences from hiv-1 ...19921438241
arteriopathy in macaques infected with simian immunodeficiency arteriopathy characterized by intimal and medial thickening and fibrosis was seen in 19 of 85 rhesus monkeys infected with simian immunodeficiency virus (siv), a lentivirus with morphologic, genetic, and biologic similarities to hiv-1 and hiv-2.19921405492
sulfation of the human immunodeficiency virus envelope glycoprotein.sulfation is a posttranslational modification of proteins which occurs on either the tyrosine residues or the carbohydrate moieties of some glycoproteins. in the case of secretory proteins, sulfation has been hypothesized to act as a signal for export from the cell. we have shown that the human immunodeficiency virus type 1 (hiv-1) envelope glycoprotein precursor (gp160) as well as the surface (gp120) and transmembrane (gp41) subunits can be specifically labelled with 35so42-. sulfated hiv-1 env ...19921433500
[the detection and quantitative determination of antigens to the human immunodeficiency virus types 1 and 2].three modifications of elisa test system for hiv antigen detection are described. they are based on igg from hiv-1 and hiv-2-infected human sera and monoclonal antibodies against hiv-1 p24 used as immunosorbents. the peroxidase/anti-hiv-igg conjugate was used in all the test systems. a possibility of quantitative detection of viral antigen in native culture fluids, lysates, and purified virus preparations was demonstrated. the test system for hiv-1 antigen detection cannot be used for hiv-2 anti ...19921441438
worldwide survey of aids vaccine challenge studies in nonhuman primates: vaccines associated with active and passive immune protection from live virus aids vaccine surveillance system (avss) was designed and implemented to track the rapidly growing international database supporting the development of promising aids vaccines. both preclinical nonhuman primate (nhp) and clinical human trials are tracked by the avss. this report presents summary data generated from the avss on the nhp aids vaccine/live virus challenge studies only. summary data on more than 100 preclinical hiv/siv vaccines are presented within the framework of 1) 13 arbitrary ...19921433265
prevalence and risk determinants of human immunodeficiency virus type 2 (hiv-2) and human immunodeficiency virus type 1 (hiv-1) in west african female prostitutes.the authors studied the prevalence and risk determinants for human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) in female prostitutes from dakar (1985-1990), ziguinchor (1987-1990), and kaolack (1987-1990), senegal, west africa. each cohort showed a distinct distribution of hivs: 10.0% hiv-2 and 4.1% hiv-1 in dakar, 38.1% hiv-2 and 0.4% hiv-1 in ziguinchor, and 27.4% hiv-2 and 1.3% hiv-1 in kaolack. in 1,275 female prostitutes from dakar, increase years of sexual activity and a histo ...19921442755
identification of infection of an australian resident with the human immunodeficiency virus type 2 (hiv-2).to present the first confirmed case of human immunodeficiency virus infection type 2 (hiv-2) in an australian resident.19921447996
prevalence of human immunodeficiency virus-infection among pregnant women attending ante-natal clinic in maiduguri, north-eastern nigeria.a seroepidemiological survey conducted among 1,059 pregnant women in maiduguri, north-eastern nigeria from september, 1988 to april, 1990 showed that 5 women or 0.47% were positive for hiv antibodies. three of the women (0.28%) were positive for hiv-1 while 2 others (0.19%) were positive for hiv-2; this is consistent with the known fact that both viruses are active in west africa, a sub-region of which nigeria is part. detailed information available on 4 of the 5 seropositive women and their hus ...19921455529
virus-specific cytotoxic t-lymphocytes in hiv-2-infected cynomolgus macaques.specific cytotoxic t-lymphocytes (ctl) are induced in humans or monkeys after infection with hiv-1 or sivmac, respectively. since, like hiv-1, hiv-2 causes aids, our objective was to determine the characteristics of the hiv-2-specific ctl response.19921466839
continued monitoring for human immunodeficiency virus type 2 infections in california. 19921471252
[adducts of 3'-azido-2,3'-dideoxythymidine 5'-phosphate or 5'-phosphonate as inhibitors of cytopathic effect and transformation of cells under the influence of retroviruses in cell culture].inhibition of hiv-1- or hiv-2-induced cytopathicity and (moloney) murine sarcoma virus (msv)-induced cell transformation by amino acid and amino alcohol adducts of either 3'-azido-2',3'-dideoxythymidine 5'-monophosphate (aztmp) or 5'-hydrogenphosphonate (azthp) were investigated. both types of nucleotide adducts inhibited replication of hiv-1 and hiv-2 in mt-4 cells at a 1.5- to 3-fold higher ec50 (50% effective concentration) than azt; and, also, selectivity indexes of these adducts were approx ...19921470177
htlv among israeli intravenous drug abusers.since human t lymphotropic virus (htlv) infection was recently described in israel and other middle eastern countries, we have investigated the presence of htlv type 1 and type 2 in a group of 299 intravenous (iv) drug abusers who were seen at a large methadone clinic in the tel aviv area in 1986-1987. we found that 1.3% were seropositive to htlv. further testing revealed that htlv1 was the only htlv serotype. in addition, no coinfection hiv1/htlv1 and no hiv2 infection were detected. since all ...19921468865
cellular proteins bound to immunodeficiency viruses: implications for pathogenesis and vaccines.cellular proteins associated with immunodeficiency viruses were identified by determination of the amino acid sequence of the proteins and peptides present in sucrose density gradient-purified human immunodeficiency virus (hiv)-1, hiv-2, and simian immunodeficiency virus (siv). beta 2 microglobulin (beta 2m) and the alpha and beta chains of human lymphocyte antigen (hla) dr were present in virus preparations at one-fifth the concentration of gag on a molar basis. antisera to hla dr, beta 2 m, as ...19921470916
detection of hiv-1 infections by pcr: evaluation in a seropositive subject study the polymerase chain reaction (pcr) performance in detecting human immunodeficiency virus (hiv) infections, we tested 53 hiv-1 seropositive patients and 29 hiv-1 seronegative subjects for four different hiv-1 dna regions. fifty-one seropositive patients were found positive by pcr with at least one primer pair, but two were repeatedly negative for all primers. weekly blood samples from 12 seropositive subjects all detected positive for at least one primer pair, but for three patients an ...19921480185
inhibition of hiv by an anti-hiv protease synthetic peptide blocks an early step of viral replication.the processing of the human immunodeficiency virus (hiv) gag and gag-pol precursor proteins by the virus-encoded protease is an essential step in maturation of infectious virus particles. like most retroviral proteases, the hiv protease belongs to the aspartyl-protease family and can be inhibited by specific inhibitors. twenty-four synthetic peptides known to be inhibitors of human renin were tested for inhibition of hiv replication in tissue cultures. one of them, a synthetic peptide analogue, ...19921480823
activation of the human immunodeficiency virus type 2 enhancer is dependent on purine box and kappa b regulatory elements.human immunodeficiency virus type 2 (hiv-2) displays several features which distinguish it from hiv-1. among the differences in these two viruses are the responses of their enhancer regions to t-cell activation. for example, stimulation of hiv-1 transcription is largely dependent on two kappa b regulatory elements. in contrast, the hiv-2 enhancer has a single kappa b site and contains additional cis-acting sequences responsive to induction. one of these sites, previously termed cd3r, is a purine ...19921501284
high level of surface cd4 prevents stable human immunodeficiency virus infection of t-cell transfectants.cd4 is the principal receptor for the human immunodeficiency virus (hiv). we have isolated and studied cd4-expressing tumor cell clones made by expressing cd4 in the t-cell tumor line hsb. two clones, one designated hsbcd4, a clone expressing low levels of cd4, and the other, hsb10xcd4, a high-expresser cd4+ clone, were studied for their ability to bind and replicate hiv. in contrast to many other cd4+ cells that down-modulate cd4 following hiv infection, the hsb10xcd4 clones continued to expres ...19921501285
3'-spiro nucleosides, a new class of specific human immunodeficiency virus type 1 inhibitors: synthesis and antiviral activity of [2'-5'-bis-o-(tert-butyldimethylsilyl)-beta-d-xylo- and -ribofuranose]-3'-spiro-5"-[4"-amino-1",2"-oxathiole 2",2"-dioxide] (tsao) pyrimidine nucleosides.a series of 3'-spiro nucleosides have been synthesized and evaluated as anti-hiv-1 agents. reaction of o-mesylcyanohydrins of furanos-3'-ulosyl nucleosides with base afforded [1-[2',5'-bis-o- (tert-butyldimethylsilyl)-beta-d-xylo- and -ribofuranosyl]]-3'-spiro-5"- [4"-amino-1",2"-oxathiole 2",2"-dioxide] derivatives of thymine, uracil and 4-n-acetylcytosine 11 and 12. desilylation of 11 and 12 gave the full deprotected 3'-spiro xylo- and ribofuranosyl nucleosides 13 and 14 or the partially 5'-o- ...19921495006
identification and characterization of fusion and processing domains of the human immunodeficiency virus type 2 envelope glycoprotein.the envelope glycoprotein of the human immunodeficiency virus type 2 (hiv-2) is synthesized as a polyprotein precursor which is proteolytically processed to produce the mature surface and transmembrane envelope glycoproteins. the processed envelope glycoprotein species are responsible for the fusion between the viral envelope and the host cell membrane during the infection process. the envelope glycoprotein also induces syncytium formation between envelope-expressing cells and receptor-bearing c ...19921501283
infection of cultured human adrenal cells by different strains of determine whether human adrenal cells can be infected by hiv.19921492929
[2',5'-bis-o-(tert-butyldimethylsilyl)]-3'-spiro-5''-(4''-amino-1'',2''-oxathiole-2'',2''-dioxide) (tsao) derivatives of purine and pyrimidinenucleosides as potent and selective inhibitors of human immunodeficiency virus type 1.the [2',5'-bis-o-(tert-butyldimethylsilyl)]-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide) (tsao) derivatives of ribofuranosylthymine, uridine, 5-bromouridine, 5-methylcytidine, inosine, and adenosine are potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) but not of other retroviruses (hiv-2, simian immunodeficiency virus, or moloney murine sarcoma virus). the 50% effective concentration (ec50) of the most active tsao congeners for inhibition of hiv-1 rep ...19921510396
mapping of immunodominant epitopes of the hiv-1 and hiv-2 integrase proteins by recombinant proteins and synthetic peptides.different parts of the human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2) integrase proteins were expressed as trpe fusion proteins in escherichia coli and used to screen human sera. in the immunoblot, all hiv/integrase-positive human sera tested reacted with the carboxy-terminal third of the integrase protein. furthermore, they crossreacted with the same part of the heterologous protein. half (50%) of the hiv-1/integrase-positive sera additionally detected antigenic epitopes in th ...19921520543
human immunodeficiency virus type ii (hiv-2) testing: a perspective.testing of blood for antibodies to the human immunodeficiency virus type 2 (hiv2) has begun. a major benefit of this testing will be the elimination of the exclusion of blood donors on the basis of geographic origin. will this test be helpful? present anti-hiv1 testing detects between 60 to 90 percent of those samples containing the hiv2 antibody. a food and drug administration (fda) licensed enzyme immunoassay for hiv1/hiv2 antibodies became available for clinical use in march of 1992. (there i ...19921524400
a novel ets-related transcription factor, elf-1, binds to human immunodeficiency virus type 2 regulatory elements that are required for inducible trans activation in t cells.human immunodeficiency virus type 1 (hiv-1) and hiv-2 are structurally related retroviruses which both cause aids in humans. although both viruses establish latency in quiescent human-peripheral-blood t cells, the asymptomatic phase of hiv-2 infection may be more prolonged than that of hiv-1. the latent phases of both hiv-1 and hiv-2 infection have been shown to be disrupted by t-cell activation, a process that requires host cell transcription factors. in the case of hiv-1, the transcription fac ...19921527846
early appearance of simian immunodeficiency virus (siv) antigen and antibodies as variables in evaluating antiviral drugs in macaques.siv infection in macaques has become an important animal model for hiv-1 infection in humans. an antibody assay was therefore developed and compared to a commercially available antigen assay with respect to their usefulness to monitor the course of simian immunodeficiency virus (siv) infection in cynomolgus monkeys. a peptide, jb6t, consisting of 21 amino acids with the sequence nswgcafrqvchttvpwvnds corresponding to a segment in the env protein of human immunodeficiency virus (hiv) type 2 was u ...19921533400
computer predictions of functional, topogenic, and antigenic domains in human immunodeficiency virus-2 envelope glycoprotein.the gp160 of hiv-2 was studied with the aid of computer programs that provide the hydrophilicity, surface probability, flexibility, and antigenicity index of the amino-acid sequence in a polypeptide chain. such analyses allow the identification of hydrophobic amino-acid domains in the polypeptide chain that may serve as putative proteolytic cleavage signals and putative antigenic domains. it was possible to define the function of hydrophobic domains in the polypeptide chain that serve as signals ...19921549912
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