the first decade of human retroviruses: a nomenclature for the clinician.the decade of the 1980s has provided at least 10 terms for human retroviruses, of which five are currently recognized as defining distinct human infectious disease agents. of these five, three are human t-cell lymphotropic viruses (htlv-i, htlv-ii, htlv-v) and two are human immunodeficiency viruses (hiv-1, hiv-2). hiv-1 and hiv-2 can cause the acquired immunodeficiency syndrome (aids), whereas htlv-i, htlv-ii, and htlv-v do not. htlv-i can cause a t-cell leukemia/lymphoma as well as a progressiv ...19911660967
[aids in africa].while aids (acquired immunodeficiency syndrome) certainly represents a worldwide health problem, the attention of many researchers and epidemiologists, besides the who itself, has recently focused on africa for the following reasons: 1) the etiologic agent of aids, the human immunodeficiency virus (hiv) (previously named htlv-iii or lav) is likely to have originated in africa. solid evidence has been accumulated that antibodies against hiv were present in african sera collected in the early 1960 ...19892483891
blood donors with indeterminate anti-p24gag reactivity in hiv-1 western blot: absence of infectivity to transfused patients and in virus culture.during a follow-up period of 23-40 months, 7 regular blood donors had persistently, and 4 had intermittently indeterminate anti-p24gag reactivity in human immunodeficiency virus (hiv)-1 western blot. serological testing and viral cultures revealed that these donors had no signs of infection for hiv-1, hiv-2, human t-cell lymphotropic virus (htlv)-4, and htlv-1. extensive interviewing and physical examination of these donors revealed neither risk factors, nor signs of hiv infection in the tested ...19892567091
serological survey of human immunodeficiency virus (hiv) in ethiopia.the presence of anti-human immunodeficiency virus 1 antibodies was tested in 5,565 serum samples from ethiopia of which 5,265 were collected from military recruits in the framework of a hepatitis b (hbv) seroepidemiological study performed on a national scale in 1985-1986; the remaining were 300 sera from a population of outpatients belonging to the arsi region. of the 5,565 sera, 121 (2.1%) were found to be repeatedly reactive by enzyme-linked immunosorbent assay (elisa) test for hiv-1 antibodi ...19892786052
relation of htlv-4 to simian and human immunodeficiency-associated viruses.human immunodeficiency virus type 1 (hiv-1) is the aetiologic agent of aids (acquired immune deficiency syndrome) in most countries and probably originated in central africa like the aids epidemic itself. evidence for a second major group of human immunodeficiency-associated retroviruses came from a report that west african human populations like wild-caught african green monkeys had serum antibodies that reacted more strongly with a simian immunodeficiency virus (stlv-3mac) (ref.6) than with hi ...19872823148
biological characterization of a simian immunodeficiency virus-like retrovirus (htlv-iv): evidence for cd4-associated molecules required for infection.we have analyzed a number of biological features of htlv-iv, a retrovirus indistinguishable from a macaque isolate of simian immunodeficiency virus (siv), and compared this virus with several strains of human immunodeficiency virus type 1 (hiv-1). although htlv-iv was found to be similar to hiv-1 in its tropism for cd4+ lymphocytes, its effects on cd4 expression and the ability of its externalized envelope molecule to form a complex directly with the cd4 molecule, a number of striking difference ...19882839686
analysis of false positive hiv-1 serologic testing in kenya.sera of 95 mothers and 129 children from nairobi, kenya, collected in 1976, and of 466 adults and 193 children of embu district, kenya, collected in 1984 and 1985, were analyzed for the presence of human immunodeficiency virus type 1 (hiv-1) antibodies. although no hiv-1 seropositivity was demonstrated by western blot analysis in both study groups, 7% of nairobi mothers and 10% of adult females from embu district had false positive results by enzyme immunoassay (eia) compared with less than 1% s ...19882840237
ultrastructure of human retroviruses.we compared the ultrastructure of the human retroviruses by thin-section electron microscopy of infected lymphocytes. virus particles form at the plasma membrane without involvement of a cytoplasmic precursor. budding forms of human t-cell leukemia virus types i and ii (htlv-i and -ii) consist of a crescent-shaped nucleoid separated from the envelope by an intermediate layer. mature forms of these viruses are about 100 nm in diameter. the nucleoid is electron lucent and almost completely fills t ...19882854553
prevalence of human t-lymphotropic retroviruses type iii (hiv) and type iv in ivory coast.serological investigations in the ivory coast indicate that, despite the rarity of overt acquired immunodeficiency syndrome (aids), human immunodeficiency virus (hiv) is widely prevalent. so also is human t-lymphotropic virus type iv (htlv-iv). the highest rates of hiv and htlv-iv seropositivity were observed in female prostitutes. these findings suggest that, like hiv, htlv-iv can be transmitted by heterosexual contact, and that the mobility of prostitutes may be an important factor in spread o ...19872880215
[retroviruses and the development of lymphoma].retroviruses are small, rna-containing enveloped viruses which are widely distributed in nature. they exist in many animal species as well as in man. exogenous virus strains are horizontally transmitted between individuals of a given species, like all other virus groups. endogenous virus strains have managed some time during evolution to infect germ line cells like oocytes and spermatocytes and are thus transmitted vertically from parents to offspring. several retrovirus strains possess oncogene ...19872890126
comparison of simian immunodeficiency virus isolates.information on the extent of genetic variability among non-human primate lentiviruses related to human immunodeficiency virus (hiv) is sorely lacking. here we describe the isolation of two molecular clones from the simian immunodeficiency virus (siv) and their use to derive restriction endonuclease maps of five siv isolates from rhesus macaques and one from a cynomolgus macaque. although similar, all six viral isolates are readily distinguishable; the single isolate from a cynomolgus macaque is ...19882893293
[clinical and virological study of a case of infection with the hiv-lav 2 virus].a case of aids due to hiv/lav2 is reported. the patient was a 32 year old man from guinea-bissau with no known risk factors. he had brain toxoplasmosis, oral thrush and chronic genital herpes. investigations for igg anti-hiv/lav1' (elisa, western blot, ripa) were negative. antibodies to hiv/lav2 were found and cultures of peripheral blood lymphocytes and cerebro-spinal fluid were positive. hiv/lav2 seems to be similar to stlv-iii (mac), stlv-iii (agm), and probably htlv-iv.19872893571
absence of antibodies to hiv-2/htlv-4 in six central african nations.we studied 1508 individuals from zaire, burundi, tanzania, zambia, kenya, and cameroon for antibodies to hiv-2/htlv-4. aids, arc, other disease or tumor patients and healthy people were sampled from 1984-1986. by radioimmunoprecipitation and sds/page analysis and/or western blot we failed to find any samples with specific antibodies to hiv-2/htlv-4 indicative of infection. in contrast, 363 of these 1508 individuals demonstrated antibodies to hiv-1/htlv-3b by the same serologic assays. hiv-2/htlv ...19872893632
the origins of hiv-1 and htlv-4/hiv-2.more sophisticated knowledge of the different strains of seemingly closely related retroviruses is essential to understanding acquired immunodeficiency syndrome (aids) and developing a successful vaccine. distinct exogenous human retroviruses include human immunodeficiency virus type 1 (hiv-1), the etiologic agent in aids; human t-lymphotropic virus type 1 (htlv-1), which has been linked with adult t-cell leukemia/lymphoma; and htlv-ii, a virus closely linked to htlv-i but not definitively impl ...19872894192
prevalence of hiv-1 and hiv-2/htlv-iv infections in luanda and cabinda, angola.a seroepidemiological study of human immune deficiency virus type 1 (hiv-1) and hiv-2/human t-lymphotropic virus type iv (hiv-2/htlv-iv) infections was performed in angola in october 1986. until then five cases of acquired immune deficiency syndrome (aids) had been registered in angola. during this study, another three cases with clinical aids were found and confirmed by hiv-1 serology. a total of 1,215 sera from groups of healthy persons and patients were tested for hiv-1 and hiv-2/htlv-iv anti ...19882905739
new human t-lymphotropic retrovirus related to simian t-lymphotropic virus type iii (stlv-iiiagm).this report describes serologic evidence for a virus similar to that known as simian t-lymphotropic virus type iii of african green monkeys (stlv-iiiagm) infecting apparently healthy people in senegal, west africa, and the isolation of virus from these individuals. serum samples from selected healthy west african people showed unusual serologic profiles when tested with antigens of htlv-iii/lav, the etiologic agent of aids, and of stlv-iiiagm. the samples reacted strongly with all of the major v ...19863006256
human t-lymphotropic virus type 4 and the human immunodeficiency virus in west africa.a new human t-lymphotropic virus (htlv-4) was recently described in healthy people from senegal. this virus has many properties in common with members of the human t-lymphotropic viruses, particularly the human immunodeficiency virus or hiv, the etiologic agent of acquired immune deficiency syndrome (aids), but does not appear to be associated with immunodeficiency-related disorders. in the present study, serum samples were obtained from 4248 individuals from six west african countries, includin ...19873033826
a new human retrovirus isolate of west african origin (sbl-6669) and its relationship to htlv-iv, lav-ii, and htlv-iiib.a new human retrovirus of west african origin (sbl-6669) has been isolated from a patient with immunological and clinical signs of immunodeficiency. using radioimmunoprecipitation assays (ripa) and western blot (wb) tests with human sera, the new virus isolate has been compared with htlv-iv, lav-ii, and the htlv-iiib prototype strain of the human immunodeficiency virus (hiv). the west african isolates appeared to be members of the same virus group since their glycoproteins were antigenically ind ...19873040053
cloning of htlv-4 and its relation to simian and human immunodeficiency viruses.although much is now known of the strain variation among the type-1 human immunodeficiency virus (hiv-1), which is the cause of aids (acquired immune deficiency syndrome) in the united states, europe, and central africa, much less is yet known about a second group of viruses that have been found in west africans. one member of this group, named human t-cell lymphotropic virus type 4 (htlv-4), has been isolated from healthy senegalese. another is the virus isolated from west africans with aids-li ...19873104797
enzyme immunoassays for the demonstration of antibodies to hiv-2sbl-6669 and htlv-iv (sivmac).enzyme-linked immunosorbent assays (elisa) were developed for the demonstration of antibodies to hiv-2 using disrupted virions of the sbl-6669 isolate of hiv-2 and the so-called human t-lymphotropic virus type iv (htlv-iv), recently found to be identical with the simian immunodeficiency virus (sivmac), as antigens. three hundred sera from west african subjects, attending an outward clinic in bissau for examination of suspected tuberculosis, were tested by these two assays as well as by a commerc ...19883134913
lack of cross-reaction in antibody-dependent cellular cytotoxicity between human immunodeficiency virus (hiv) and hiv-related west african strains.sera from individuals infected with human immunodeficiency virus (hiv) and hiv-related west african viruses can mediate high-titered, virus-specific antibody-dependent cellular cytotoxicity (adcc) in all stages of infection. no cross-reactive adcc can be detected between hiv and hiv-related west african strains lav-2, htlv-iv, and sbl-6669. because these two groups of viruses have antigenically distinct envelope glycoproteins, adcc-mediating antibodies are most likely directed against envelope a ...19883335784
evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors.blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (hiv) who showed atypical patterns of viral core protein reactivity on western blot were monitored for several months. characterization of their antibodies was performed by 1) use of recombinant hiv proteins; 2) determination of cross-reactivity to htlv-i, htlv-ii, and htlv-iv: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. nineteen of 20 d ...19883420668
a quantitative bioassay for hiv-1 based on trans-activation.a bioassay that is based on trans-activation has been developed for the detection and quantitation of the human immunodeficiency virus type 1 (hiv-1). indicator cell lines were constructed that contain the hiv-1 long terminal repeat ligated to the chloramphenicol acetyltransferase (cat) gene. infection of these cells by hiv activates the expression of cat protein. isolates of hiv-1 with divergent nucleotide sequences activated the indicator cell lines to a similar extent, approximately 500- to 1 ...19883422113
sequence of simian immunodeficiency virus and its relationship to the human immunodeficiency viruses.the characterization of hiv-1 (htlv-iii/lav), the human retrovirus associated with aids (acquired immune deficiency syndrome) has led to the identification of a group of related human and simian retroviruses which also infect cd4-bearing t lymphocytes. simian t-lymphotropic virus type iii (simian immodeficiency virus) from macaques (stlv-iiimac) induces symptoms similar to those of aids in infected macaques, but isolates from african green monkeys (stlv-iiiagm) and mangabeys (stlv-iimm) appear t ...19873497350
the genome organization of stlv-3 is similar to that of the aids virus except for a truncated transmembrane protein.nucleotide sequence analysis of the 3' portion of the genome of simian t-lymphotropic virus type 3 from african green monkeys (stlv-3agm) reveals that it has the same general genome structure as the human immunodeficiency virus (hiv-1), the etiologic agent of aids. short segments of strong amino acid homology and similar predicted protein structure characterize the tat and art/trs open reading frames (orf) of both viruses. strong conservation of 3' orf and of another, cs-orf, for which no protei ...19873646094
molecular analysis of human immunoglobulin heavy chain variable region associated determinants recognized by anti-vh3 antibodies 7b4, b6 and d12.7b4, b6 and d12 are murine monoclonal antibodies (moab) that bind to some human immunoglobulin heavy chain products of the closely related v3-30, v3-30.3 and v3-33 genes from the vh3 family. b6 and d12 have additional reactivities with some immunoglobulins (ig) encoded by the v3-11 and v3-7 genes; d12 also reacts with some v3-43 gene ig. we show here, by site-directed mutagensis, that the lysine at position 57 in the complementarity-determining region 2 (cdr-2) of the v3-30 gene product is cruci ...200011013004
[the htl iv virus: a new human retrovirus without pathogen protection against the htlv iii/lav virus?].the aids epidemic has spread to central and eastern africa, however in western africa it appears to have spread very little, if at all. a study was conducted on 569 adult senegalese subjects at risk for aids to determine the prevalence of infection. aids was detected by enzyme linked immunosorbent assay, with confirmation by western blot. the methods used are described in detail. the seropositivity rates were 5% in prostitutes, 1.2% in patients with tuberculosis, and 0.8% in the controls. 2 ...198612281131
[new human retroviruses: htlv-3 and htlv-4].human t cell leukemia/lymphoma virus type 1 and 2 (htlv-1 and htlv-2), together with their simian counterparts (stlv-1, stlv-2 and stlv-3), belong to the primate t lymphotropic viruses group (ptlv). htlv-1 infects 15 to 20 million people worldwide, while stlv-1 is endemic in a number of simian species living in the old world. due to the high percentage of homologies between htlv-1 and stlv-1 strains, it has now been widely accepted that most htlv-1 subtypes arose from interspecies transmission b ...200516555510
no genetic evidence for involvement of deltaretroviruses in adult patients with precursor and mature t-cell neoplasms.the deltaretrovirus genus comprises viruses that infect humans (htlv), various simian species (stlv) and cattle (blv). htlv-i is the main causative agent in adult t-cell leukemia in endemic areas and some of the simian t-cell lymphotropic viruses have been implicated in the induction of malignant lymphomas in their hosts. blv causes enzootic bovine leukosis in infected cattle or sheep. during the past few years several new deltaretrovirus isolates have been described in various primate species. ...200717284327
short communication: absence of evidence of htlv-3 and htlv-4 in patients with large granular lymphocyte (lgl) leukemia.clonal disorders of large granular lymphocytes (lgl) result in leukemia due to the expansion of a discrete subset of either cd3(+) t cells or natural killer (nk) cells. it has been hypothesized that a viral antigen acts as the initial stimulus causing the expansion of these cells. the possible involvement of human t cell lymphotropic virus types 1 and 2 (htlv-1 and htlv-2) in this disease has been studied but no conclusive evidence has linked either virus with lgl leukemia. in this study, we exa ...200819102684
ancient, independent evolution and distinct molecular features of the novel human t-lymphotropic virus type 4.human t-lymphotropic virus type 4 (htlv-4) is a new deltaretrovirus recently identified in a primate hunter in cameroon. limited sequence analysis previously showed that htlv-4 may be distinct from htlv-1, htlv-2, and htlv-3, and their simian counterparts, stlv-1, stlv-2, and stlv-3, respectively. analysis of full-length genomes can provide basic information on the evolutionary history and replication and pathogenic potential of new viruses.200919187529
discovery and significance of new human t-lymphotropic viruses: htlv-3 and htlv-4.human t-lymphotropic virus type 1 (htlv-1) and type 2 (htlv-2) were discovered approximately 30 years ago and they are associated with various lymphoproliferative and neurological diseases. the estimated number of infected people is 10-20 million worldwide. in 2005, two new htlv-1/htlv-2-related viruses were detected, htlv-3 and htlv-4, from the same geographical area of africa. in the last 4 years, their complete genomic sequences were determined and some of their characteristic features were s ...200919968515
prevalence of syphilis, human immunodeficiency virus, hepatitis b virus, and human t-lymphotropic virus infections and coinfections during prenatal screening in an urban northeastern brazilian evaluate prevalences of treponema pallidum, human immunodeficiency virus (hiv), human t-lymphotropic virus (htlv), and hepatitis b virus (hbv) infections and coinfections during prenatal screening in an urban northeastern brazilian population through a large dataset.201526255887
zoonotic transmission of two new strains of human t-lymphotropic virus type 4 in hunters bitten by a gorilla in central africa.molecular screening of 300 at-risk people from central africa identified 2 human t-lymphotropic virus (htlv)-4-infected individuals. a zoonotic origin of infection was suggested, as both individuals reported being severely bitten by a gorilla during hunting activities. one strain was highly divergent and was designated as the htlv-4 subtype-b prototype.201627325689
human t lymphotropic virus type 1 (htlv-1): molecular biology and oncogenesis.human t lymphotropic viruses (htlvs) are complex deltaretroviruses that do not contain a proto-oncogene in their genome, yet are capable of transforming primary t lymphocytes both in vitro and in vivo. there are four known strains of htlv including htlv type 1 (htlv-1), htlv-2, htlv-3 and htlv-4. htlv-1 is primarily associated with adult t cell leukemia (atl) and htlv-1-associated myelopathy/tropical spastic paraparesis (ham/tsp). htlv-2 is rarely pathogenic and is sporadically associated with n ...201021994719
HTLV-3/STLV-3 and HTLV-4 viruses: discovery, epidemiology, serology and molecular aspects.Human T cell leukemia/lymphoma virus Type 1 and 2 (HTLV-1 and HTLV-2), together with their simian counterparts (STLV-1, STLV-2), belong to the Primate T lymphotropic viruses group (PTLV). The high percentage of homologies between HTLV-1 and STLV-1 strains, led to the demonstration that most HTLV-1 subtypes arose from interspecies transmission between monkeys and humans. STLV-3 viruses belong to the third PTLV type and are equally divergent from both HTLV-1 and HTLV-2. They are endemic in several ...201121994771
making sense out of antisense transcription in human t-cell lymphotropic viruses (htlvs).retroviral gene expression generally depends on a full-length transcript that initiates in the 5' long terminal repeat (ltr), which is either unspliced or alternatively spliced. we and others have demonstrated the existence of an antisense transcript initiating in the 3' ltr of the human t-cell leukemia virus type 1 (htlv-1) that is involved in the production of hbz (htlv-1 basic leucine zipper (bzip) factor). hbz is a fos-like factor capable of inhibiting tax-mediated activation of the htlv-1 l ...201121994742
human t-cell lymphotropic virus type 3 (htlv-3)- and htlv-4-derived antisense transcripts encode proteins with similar tax-inhibiting functions but distinct subcellular localization.the human t-cell lymphotropic virus (htlv) retrovirus family is composed of the well-known htlv type 1 (htlv-1) and htlv-2 and the most recently discovered htlv-3 and htlv-4. like other retroviruses, htlv-1 and htlv-2 gene expression has been thought to be orchestrated through a single transcript. however, recent reports have demonstrated the unique potential of both htlv-1 and htlv-2 to produce an antisense transcript. furthermore, these unexpected and newly identified transcripts lead to the s ...201121917984
identification and molecular characterization of new simian t-cell lymphotropic viruses (stlv) in nonhuman primates bushmeat from the democratic republic of congo.four types of htlv have been described (htlv-1 to 4) with three of them having closely related simian virus analogues named stlv-1, 2 and 3. to assess the risk of cross-species transmissions of stlvs from non-human primates to humans in the democratic republic of congo, a total of 330 samples, derived from primate bushmeat, were collected at remote forest sites where people rely on bushmeat for subsistence. stlv prevalences and genetic diversity were estimated by pcr and sequence analysis of tax ...201121827287
the human htlv-3 and htlv-4 retroviruses: new members of the htlv family.human t cell leukemia/lymphoma virus type 1 and 2 (htlv-1 and htlv-2), together with their simian counterparts (stlv-1, stlv-2), belong to the primate t lymphotropic viruses group (ptlv). htlv-1 infects 15 to 20million people worldwide, while stlv-1 is endemic in a number of simian or ape species living in africa or asia. the high percentage of homologies between htlv-1 and stlv-1 strains, led to the demonstration that most htlv-1 subtypes arose from interspecies transmission between monkeys and ...200918456423
identification and molecular characterization of new stlv-1 and stlv-3 strains in wild-caught nonhuman primates in cameroon.humans and simian species are infected by deltaretroviruses (htlv and stlv respectively), which are collectively called primate t-cell lymphotropic viruses (ptlvs). in humans, four types of htlv have been described (htlv-1 to -4) with three of them having closely related simian virus analogues named stlv-1, 2 and 3. in this study, our aim was to search for a simian htlv-4-related virus and to document and characterize further the diversity of stlv infections in wild primate populations. we scree ...200817976676
immunogenic nature of a pol gene product of htlv-iii/lav.the present studies were initiated to define the coding region of a 34 kilodalton (kd) protein (p34) frequently observed with antibodies from htlv-iii/lav-infected people by immunoblotting and radioimmunoprecipitation (rip) techniques. we have directly mapped this viral protein to the pol gene of htlv-iii/lav by radiolabeled amino acid sequence analysis. this region at the 3' end of the pol gene is predicted to encode the endonuclease/integrase of the virus. the seroprevalence rate of antibodies ...19873024760
a stlv-iii related human retrovirus, htlv-iv: analysis of cross-reactivity with the human immunodeficiency virus (hiv).a category of viruses has been identified which is related to human immunodeficiency virus (hiv) but is more closely related to a group of simian retroviruses (stlv-iii). these viruses named htlv-iv, lav-ii, or sbl-6669, are prevalent in west-africa. in this study, we analysed the cross-reactivity at the protein level between htlv-iv and hiv (htlv-iiib). the results indicate that most people infected with htlv-iv have antibodies that react to the major gag protein of hiv p 24. there is also a hi ...19872444614
a gorilla reservoir for human t-lymphotropic virus type 4.of the seven known species of human retroviruses only one, human t-cell lymphotropic virus type 4 (htlv-4), lacks a known animal reservoir. we report the largest screening for simian t-cell lymphotropic virus (stlv-4) to date in a wide range of captive and wild non-human primate (nhp) species from cameroon. among the 681 wild and 426 captive nhps examined, we detected stlv-4 infection only among gorillas by using htlv-4-specific quantitative polymerase chain reaction. the large number of samples ...201426038495
human t-cell leukemia virus type 3 (htlv-3) and htlv-4 antisense-transcript-encoded proteins interact and transactivate jun family-dependent transcription via their atypical bzip motif.human t-cell leukemia virus types 3 and 4 (htlv-3 and htlv-4) are recently isolated retroviruses. we have previously characterized htlv-3- and htlv-4-encoded antisense genes, termed aph-3 and aph-4, respectively, which, in contrast to hbz, the htlv-1 homologue, do not contain a typical bzip domain (m. larocque é halin, s. landry, s. j. marriott, w. m. switzer, and b. barbeau, j. virol. 85:12673-12685, 2011, doi:10.1128/jvi.05296-11). as hbz differentially modulates the transactivation potential ...201424872589
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