| 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 ... | 2008 | 17976676 |
| ancient dna identification of early 20th century simian t-cell leukemia virus type 1. | the molecular identification of proviruses from ancient tissues (and particularly from bones) remains a contentious issue. it can be expected that the copy number of proviruses will be low, which magnifies the risk of contamination with retroviruses from exogenous sources. to assess the feasibility of paleoretrovirological studies, we attempted to identify proviruses from early 20th century bones of museum specimens while following a strict ancient dna methodology. simian t-cell leukemia virus t ... | 2008 | 18296697 |
| 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 ... | 2009 | 18456423 |
| new insights into prevalence, genetic diversity, and proviral load of human t-cell leukemia virus types 1 and 2 in pregnant women in gabon in equatorial central africa. | human t-cell leukemia virus type 1 (htlv-1) is highly endemic in areas of central africa; mother-to-child transmission and sexual transmission are considered to be the predominant routes. to determine the prevalence and subtypes of htlv-1/2 in pregnant women in gabon, we conducted an epidemiological survey in the five main cities of the country. in 907 samples, the htlv-1 seroprevalence was 2.1%, which is lower than that previously reported. only one case of htlv-2 infection was found. the htlv- ... | 2008 | 18845819 |
| 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. | 2009 | 19187529 |
| simian t-lymphotropic virus diversity among nonhuman primates, cameroon. | cross-species transmission of retroviruses is common in cameroon. to determine risk for simian t-cell lymphotropic virus (stlv) transmission from nonhuman primates to hunters, we examined 170 hunter-collected dried blood spots (dbs) from 12 species for stlv. pcr with generic tax and group-specific long terminal repeat primers showed that 12 (7%) specimens from 4 nonhuman primate species were infected with stlv. phylogenetic analyses showed broad diversity of stlv, including novel stlv-1 and stlv ... | 2009 | 19193260 |
| one-step, multiplex, real-time pcr assay with molecular beacon probes for simultaneous detection, differentiation, and quantification of human t-cell leukemia virus types 1, 2, and 3. | a single-tube, multiplex, real-time pcr assay with molecular beacons was established in which various probes were used for the simultaneous detection, differentiation, and quantification of human t-cell leukemia virus types 1, 2, and 3 (htlv-1, htlv-2, and htlv-3, respectively) and of simian t-cell leukemia virus types 1 and 3 (stlv-1 and stlv-3, respectively). the quantitative amplification of the standards with mt4 (htlv-1) and c19 (htlv-2) cell lines and a molecular clone of htlv-3 was linear ... | 2009 | 19213697 |
| morphological characteristics of malignant t-cell lymphomas in baboons. | fifteen cases of generalized peripheral t-cell non-hodgkin's lymphoma in baboons were phenotyped immunologically and morphologically. using the updated kiel classification the cases included low-grade and high-grade lymphomas and low-grade lymphomas that had transformed into high-grade lymphomas. in the low-grade group there were seven cases of lymphocytic type, partly corresponding to chronic lymphocytic leukaemia of t type and to t-zone lymphoma in man. in addition there were four cases of pro ... | 1993 | 8385378 |
| incidence of lymphoma in a captive-bred colony of hamadryas baboons (papio hamadryas). | to assess the incidence of lymphoma and wasting-related deaths in the national baboon colony of australia and relate it to the presence of simian t-cell lymphotrophic virus 1 (stlv-1) infection. | 2009 | 19489781 |
| phylogenetic subtypes of human t-lymphotropic virus type i and their relations to the anthropological background. | isolates of human t-lymphotropic virus type i (htlv-i) were phylogenetically analyzed from native inhabitants in india and south america (colombia and chile) and from ainu (regarded as pure japanese descendants from the preagricultural "jomon" period). their genomes were partially sequenced together with isolates from gabon in central africa and from ghana in west africa. the phylogenetic tree was constructed from the sequence data obtained and those of previously reported htlv-i isolates and si ... | 1994 | 8302841 |
| identification of a novel motif responsible for the distinctive transforming activity of human t-cell leukemia virus (htlv) type 1 tax1 protein from htlv-2 tax2. | human t-cell leukemia virus type 1 (htlv-1) is a causative agent of adult t-cell leukemia (atl), whereas its relative htlv-2 is not associated with any malignancies including atl. htlv-1 tax1 transformed a t-cell line from interleukin (il)-2-dependent growth to il-2-independent growth, with an activity that was much more potent in comparison to htlv-2 tax2. this distinction was mediated by at least two tax1 specific functions, an interaction with host cellular factors through the pdz domain bind ... | 2009 | 19761585 |
| 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 ... | 2009 | 19968515 |
| diversity of stlv-1 strains in wild chimpanzees (pan troglodytes verus) from côte d'ivoire. | simian t-lymphotropic viruses type 1 (stlv-1) are regarded as a highly conserved group of viruses with genotypes clustering according to geographic regions rather than to infected species. in free living west african chimpanzees we have described a variety of stlv-1 strains and suggested that this diversity results from interspecies transmissions. here we present new data on stlv-1 infections in these chimpanzees with the presence of two new distinct clades, proposing the establishing of two new ... | 2010 | 20214935 |
| genotyping of human t cell lymphotropic virus type i using australo-melanesian topotype-specific oligonucleotide primer-based polymerase chain reaction: insights into viral evolution and dissemination. | sequence variants of human t cell lymphotropic virus type i (htlv-i), genetically distinct from cosmopolitan strains of htlv-i from japan, the americas, the caribbean, and africa, have been discovered among melanesians in papua new guinea and the solomon islands and among australian aboriginals. by using oligonucleotide primer pairs derived from sequences unique to the gp46- and gp21-encoding regions of the env gene of the melanesian htlv-i variants, htlv-i strains from widely separated geograph ... | 1994 | 7995973 |
| highly active antiretroviral treatment against stlv-1 infection combining reverse transcriptase and hdac inhibitors. | approximately 3% of all human t-lymphotropic virus type 1 (htlv-1)-infected persons will develop a disabling inflammatory disease of the central nervous system known as htlv-1-associated myelopathy/tropical spastic paraparesis, against which there is currently no efficient treatment. as correlation exists between the proviral load (pvl) and the clinical status of the carrier, it is thought that diminishing the pvl could prevent later occurrence of the disease. we have conducted a study combining ... | 2010 | 20587783 |
| short communication: epidemiological evidence that simian t-lymphotropic virus type 1 in macaca fuscata has an alternative transmission route to maternal infection. | serological inspection of simian t-lymphotropic virus type 1 was conducted for a wild colony of macaca fuscata, which was captured in the middle honshu, japan. the increase of positive rate after the juvenile stage with the positive rate reaching 100% (or 35/35) in youngster and adult stages, was observed. this finding suggests that, in contrast with human t-lymphotropic virus type 1, horizontal transmission play an important role in increasing prevalence of stlv-1 with age among m. fuscata. | 2011 | 20854200 |
| [large-cell anaplastic malignant cd30/ki-1-positive t-type lymphoma, associated with stlv-1 virus (baboon malignant lymphoma model]. | large-cell anaplastic malignant lymphoma of t-type (t-lcal) as an original form among human non-hodgkin's malignant lymphomas in updated kiel classification (1988) was defined. in human pathology t-lcal presents a considerable diagnostic difficulties and is not associated with htlv except some cutaneous forms. comparative examination was carried out in 5 cases of baboon t-lcal as a part of long-term investigation of the lymphoma outbreak in sukhumi monkey stock. in tumor-bearing baboons routine ... | 1995 | 7615247 |
| human retroviruses: a common virology. | there are five known human retroviruses: human t-lymphotropic virus-i (htlv-i), htlv-ii, htlv-v, human immunodeficiency virus-1 (hiv-1), and hiv-2. these are related to animal lentiviruses. the simian retroviruses, simian t-lymphotropic virus-i (stlv-i) and stlv-iii are related closely to htlv-i and hiv-2 respectively. htlv-i and htlv-ii and, possibly, htlv-v are transforming agents that immortalize the cd4 cell. in contrast, hiv-1 and hiv-2 cause this cell to lyse, resulting in immunodeficiency ... | 1989 | 2520546 |
| evaluation of a htlv-1 subunit vaccine in prevention of experimental stlv-i infection in macaca nemestrina. | pig-tailed macaques were vaccinated with a human t-cell lymphotropic virus type i (htlv-i) subunit vaccine. vaccinates and controls were challenged with simian t-cell lymphotropic virus type i (stlv-i)-infected cells. vaccination yielded antibody responses to htlv-i and stlv-i gag and env precursors. controls developed htlv-i and stlv-i antibody to gag and tax protein. immunization produced syncytium inhibiting antibody and cellular cytotoxicity to virus-infected cells. reverse transcriptase act ... | 1990 | 2172541 |
| 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 ... | 2011 | 21994771 |
| animal models on htlv-1 and related viruses: what did we learn? | retroviruses are associated with a wide variety of diseases, including immunological, neurological disorders, and different forms of cancer. among retroviruses, oncovirinae regroup according to their genetic structure and sequence, several related viruses such as human t-cell lymphotropic viruses types 1 and 2 (htlv-1 and htlv-2), simian t cell lymphotropic viruses types 1 and 2 (stlv-1 and stlv-2), and bovine leukemia virus (blv). as in many diseases, animal models provide a useful tool for the ... | 2012 | 23049525 |
| simian t cell leukemia virus type-1-specific killer t cells in naturally infected african green monkey carriers. | studies were made on the cellular immunity of 13 african green monkeys (cercopithecus aethiops) naturally infected with simian t cell leukemia virus type 1 (stlv-1), closely related to human t cell leukemia virus type 1. they were classified into 3 groups: 1) progressed carrier, 2) carrier, and 3) normal control. this grouping was made according to their hematologic features, i.e., number of peripheral white blood cells, existence of blastoid cells, presence of stlv-1 ag on pbl and anti-stlv-1 a ... | 1990 | 2155962 |
| dual simian foamy virus/human immunodeficiency virus type 1 infections in persons from côte d'ivoire. | zoonotic transmission of simian retroviruses in west-central africa occurring in primate hunters has resulted in pandemic spread of human immunodeficiency viruses (hivs) and human t-lymphotropic viruses (htlvs). while simian foamy virus (sfv) and simian t- lymphotropic virus (stlv)-like infection were reported in healthy persons exposed to nonhuman primates (nhps) in west-central africa, less is known about the distribution of these viruses in western africa and in hospitalized populations. we s ... | 2016 | 27310836 |
| production of a recombinant human t-cell leukemia virus type-i trans-activator (tax1) antigen and its utilization for generation of monoclonal antibodies against various epitopes on the tax1 antigen. | a 42-kda recombinant protein, px141, consisting of the trans-activator protein encoded by human t-cell leukemia virus (htlv-1) (tax1 antigen) and the amino-terminal fusion peptide of 12 amino acid residues of the alpha-peptide encoded by the plasmid puc19 was produced. in order to investigate the immunogenicity of the tax1 antigen, mice were immunized with the purified px141 and 4 anti-tax1 monoclonal antibodies (mabs) designated taxy-1, taxy-6, taxy-7 and taxy-8 were generated, and their reacti ... | 1991 | 1710610 |
| development of a monoclonal antibody-based p24 capsid antigen detection assay for htlv-i, htlv-ii, and stlv-i infection. | a monoclonal antibody-based antigen capture enzyme-linked immunosorbent assay (elisa) was developed and employed to detect p24 capsid antigen from human t-cell lymphotropic viruses type i and ii (htlv-i, htlv-ii), simian t-cell lymphotropic virus type i (stlv-i)-infected cell lines, and from mononuclear cell cocultures of htlv-infected humans and stlv-i infected monkeys. a monoclonal antibody specific for htlv p24 and p53 capsid antigens was coated onto 96-well microtiter plates to capture htlv/ ... | 1992 | 1318063 |
| [mechanisms of viral emergence and interspecies transmission: the exemple of simian foamy viruses in central africa]. | a large proportion of viral pathogens that have emerged during the last decades in humans are considered to have originated from various animal species. this is well exemplified by several recent epidemics such as those of nipah, severe acute respiratory syndrome, avian flu, ebola, monkeypox, and hantaviruses. after the initial interspecies transmission per se, the viruses can disseminate into the human population through various and distinct mechanisms. some of them are well characterized and u ... | 2013 | 26137812 |
| new insights in htlv-i phylogeny by sequencing and analyzing the entire envelope gene. | the htlv-i envelope plays a major role in the process of target cell infection. it is implied in the recognition of the viral receptor(s), penetration of the viral genetic material, and induction of host immunity to the virus. it is thus important to study the genetic variability of the viral env gene as well as its variation in terms of evolution. in a new approach to these features, we sequenced the entire env gene of 65 htlv-i isolates originating from gabon, french guiana, west indies, and i ... | 2005 | 15665642 |
| three spontaneous lymphomas in a colony of cotton-top tamarins (saguinus oedipus). | cotton-top tamarins are well known for their prevalence to idiopathic colitis and adenocarcinomas. at the same time, information on the incidence of spontaneous lymphomas in this highly endangered species is rare. records, 212 in total, of cotton-top tamarins (saguinus oedipus) necropsied at the german primate centre between 1979 and 1998 were viewed to establish the prevalence of lymphoid neoplasms. neoplastic lymphoid cell growth was mentioned in three necropsy records. immunohistology was per ... | 2001 | 11990532 |
| molecular and phylogenetic analyses of 16 novel simian t cell leukemia virus type 1 from africa: close relationship of stlv-1 from allenopithecus nigroviridis to htlv-1 subtype b strains. | a serological survey searching for antibodies reacting with human t-cell leukemia virus type 1 (htlv-1) antigens was performed on a series of 263 sera/plasma obtained from 34 monkey species or subspecies, originating from different parts of africa. among them, 34 samples exhibited a typical htlv-1 western blot pattern. polymerase chain reaction was performed with three primer sets specific either to htlv-1/stlv-1 or htlv-2 and encompassing gag, pol, and tax sequences, on genomic dna from periphe ... | 2001 | 11531406 |
| dating the origin of the african human t-cell lymphotropic virus type-i (htlv-i) subtypes. | to investigate the origin of the african ptlv-i virus, we phylogenetically analyzed the available htlv-i and stlv-i strains. we also attempted to date the presumed interspecies transmissions that resulted in the african htlv-i subtypes. molecular-clock analysis was performed using the tamura-nei substitution model and gamma distributed rate heterogeneity based on the maximum-likelihood topology of the combined long-terminal-repeat and env third-codon-position sequences. since the molecular clock ... | 2001 | 11264418 |
| development of neurologic diseases in a patient with primate t lymphotropic virus type 1 (ptlv-1). | virus transmission from various wild and domestic animals contributes to an increased risk of emerging infectious diseases in human populations. htlv-1 is a human retrovirus associated with acute t-cell leukemia and htlv-1-associated myelopathy/tropical spastic paraparesis (ham/tsp). htlv-1 originated from ancient zoonotic transmission from nonhuman primates, although cases of zoonotic infections continue to occur. similar to htlv-1, the simian counterpart, stlv-1, causes chronic infection and l ... | 2016 | 27519553 |
| enhancement of anti-stlv-1/htlv-1 immune responses through multimodal effects of anti-ccr4 antibody. | human t-cell leukemia virus type 1 (htlv-1) causes adult t-cell leukemia and inflammatory diseases. because anti-htlv-1 immune responses are critical for suppressing infected cells, enhancing cellular immunity is beneficial for the treatment of htlv-1-associated diseases. using simian t-cell leukemia virus type 1 (stlv-1) infected japanese macaques, we analyzed the immune responses to viral antigens and the dynamics of virus-infected cells. the chemokine receptor ccr4 is expressed on stlv-1 infe ... | 2016 | 27250643 |
| [a virus called htlv-1. epidemiological aspects]. | geographic distribution and transmission: htlv-1 is not an ubiquitous virus. 15 to 25 million subjects are estimated to be infected. endemic areas are recognized in southern japan, tropical africa, the caribbean, some areas in central and south america, and in few regions of the middle east and melanesia. in these endemic zones, 0.5 to 50% of the population, depending on age and gender, have specific antibodies against htlv-1 antigens. interhuman transmission can occur from mother to child by pr ... | 2000 | 11196061 |
| molecular characterization and phylogenetic analyses of a new simian t cell lymphotropic virus type 1 in a wild-caught african baboon (papio anubis) with an indeterminate stlv type 2-like serology. | stlv-1 viruses are closely related to htlv-1 and infect many african monkey species. seroreactivities of monkeys infected by stlv-1 are nearly identical to those of htlv-1-infected individuals. in some cases, stlv-1 are, sequence-wise, indistinguishable from htlv-1, and cannot be separated from them on the basis of phylogenetic analyses. htlv-2-related simian viruses have been rarely reported. such stlv-2 viruses, present in african bonobo (pan paniscus), possess a genomic organization related t ... | 2000 | 11153087 |
| different models, different trees: the geographic origin of ptlv-i. | using nucleotide sequences from three genomic regions of the human and simian t-cell lymphotropic virus type i (htlv-i/stlv-i)-consisting of 69 sequences from a 140-bp segment of the pol region, 98 sequences from a 503-bp segment of the ltr, and 154 sequences from a 386-bp segment of the env region-we tested two hypotheses concerning the geographic origin and evolution of stlv-i and htlv-i. first, we tested the assumption of equal rates of evolution along stlv-i and htlv-i lineages using a likel ... | 1999 | 10603262 |
| the prevalence of antibodies to simian t-cell leukaemia/lymphotropic virus (stlv-i) in non-human primate colonies in kenya. | retroviruses closely related to the human t-cell leukaemia/lymphotrophic virus type i (htlv-i) have been detected in several, non-human, primate species. these retroviruses are called simian t-lymphotrophic virus type i (stlv-i). infection with stlv-i has been associated with lymphoma and leukaemia in macaques, baboons, african green monkeys and gorillas. however, no stlv-i infection has been detected in new world primates, although stlv-ii has been detected in spider monkeys. when sera from 10 ... | 1999 | 10562831 |
| tcf1 and lef1 act as t-cell intrinsic htlv-1 antagonists by targeting tax. | human t-cell leukemia virus type 1 (htlv-1) is a delta-type retrovirus that induces malignant and inflammatory diseases during its long persistence in vivo. htlv-1 can infect various kinds of cells; however, htlv-1 provirus is predominantly found in peripheral cd4 t cells in vivo. here we find that tcf1 and lef1, two wnt transcription factors that are specifically expressed in t cells, inhibit viral replication through antagonizing tax functions. tcf1 and lef1 can each interact with tax and inhi ... | 2015 | 25646419 |
| [cytogenic characteristics and virogenic status of lymphoid cells from malignant baboon lymphomas]. | four lymphoid cell cultures obtained from papio hamadryads with malignant lymphomas were studied. the cultured cells produced two lymphotropic ebv-like herpes virus of papio (hvp) and t-lymphotropic monkey retrovirus stlv-1 (htlv-1 family) or hvp alone. more than 100 subcultured cell lines were shown to remain mixed b- and t-cellular, the levels of t cells of different subpopulations were 15-50%. cytogenetic investigations showed that one of the 4 cultures was tumorogenic and the others were der ... | 1999 | 10467886 |
| constitutive release of ifnγ and il2 from peripheral blood mononuclear cells of rhesus macaques (macaca mulatta) infected with simian t-lymphotropic virus type 1. | simian t-cell lymphotropic viruses (stlv), the nonhuman primate counterparts of human t-cell lymphotropic viruses (htlv), are endemic in many populations of african and asian monkeys and apes. although an etiologic link between stlv1 infection and lymphoproliferative disorders such as malignant lymphomas has been suggested in some nonhuman primate species, most stlv infections are inapparent, and infected animals remain clinically healthy. the retroviral transactivator, tax, is well known to inc ... | 2013 | 24326227 |
| characterization of simian t-cell leukemia virus type 1 in naturally infected japanese macaques as a model of htlv-1 infection. | human t-cell leukemia virus type 1 (htlv-1) causes chronic infection leading to development of adult t-cell leukemia (atl) and inflammatory diseases. non-human primates infected with simian t-cell leukemia virus type 1 (stlv-1) are considered to constitute a suitable animal model for htlv-1 research. however, the function of the regulatory and accessory genes of stlv-1 has not been analyzed in detail. in this study, stlv-1 in naturally infected japanese macaques was analyzed. | 2013 | 24156738 |
| quantification of human t-cell lymphotropic virus type 1 proviral load by quantitative competitive polymerase chain reaction. | the polymerase chain reaction (pcr) has been established as a highly sensitive technique for detection of viral dna or rna. however, due to inherent limitations of pcr the amount of amplified product often does not correlate with the initial amount of template dna. this is particularly true for pcr detection of viral infections that are characterized by low in vivo viral copy numbers in certain stages of the infection, such as human t-cell lymphotropic virus type 1 (htlv-1) and simian t-cell lym ... | 1998 | 9870588 |
| acute fulminant sarcocystosis in a captive-born rhesus macaque. | a captive-born juvenile female rhesus macaque (macaca mulatta) was acquired from a commercial breeder and placed in quarantine. within 8 days of arrival, the animal became anorexic, inactive, and dehydrated. subsequently, generalized edema and facial ecchymoses developed, and despite supportive therapy, the animal became moribund and was euthanatized. macroscopic examination showed diffuse stippling and streaking of the myocardium. histopathologic examination revealed multifocal to coalescing my ... | 1998 | 9823591 |
| two new human t-lymphotropic virus type i phylogenetic subtypes in seroindeterminates, a mbuti pygmy and a gabonese, have closest relatives among african stlv-i strains. | six new htlv-i strains from seroindeterminate individuals were analyzed: four from gabon, one from a mbuti efe pygmy in congo (formerly zaire), and one from a congolese patient residing in belgium. the ltr and env regions were sequenced and phylogenetic analyses were performed to characterize the new strains. nucleotide divergence and phylogeny results showed that four of the new strains belong to the htlv-ib central african subtype. the other two strains, one from the efe pygmy and one from gab ... | 1998 | 9657946 |
| isolation of sooty mangabey simian t-cell leukemia virus type i [stlv-i(sm)] and characterization of a mangabey t-cell line coinfected with stlv-i(sm) and simian immunodeficiency virus sivsmmpbj14. | it has been postulated that dual infections of humans with human immunodeficiency virus (hiv) and human t-cell leukemia/lymphotropic virus (htlv) may potentiate disease progression. counterparts of both of these pathogenic human retroviruses have been identified in various simian species indigenous to asia and africa, including sooty mangabey monkeys (cercocebus atys). using peripheral blood mononuclear cells (pbmc) from a mangabey naturally infected with both siv and stlv-i, t-cell lines were e ... | 1997 | 9281507 |
| molecular characterization and phylogenetic analyses of a new, highly divergent simian t-cell lymphotropic virus type 1 (stlv-1marc1) in macaca arctoides. | a serological survey of a captive colony of asian monkeys indicated that six macaca arctoides had antibodies to human t-cell leukemia/lymphotropic viruses (htlv). over a 4-year interval, sera from these animals continued to exhibit a peculiar western blot (wb) pattern resembling an htlv-2 pattern (p24gag reactivity of equal or greater intensity than that of p19gag and a strong reactivity to recombinant gp21) but also exhibiting, in five of six cases, a reactivity against mta-1, an htlv-1 gp46 pe ... | 1997 | 9223528 |
| htlv-1 p12i protein sequences from south america: truncated proteins and common genetic signatures. | p12 px orf-i (p12i) of simian t cell lymphotropic virus 1 from central and west africa is a 91-amino acid (aa) protein, contrasting with the known p12 sequences from human t cell lymphotropic virus type 1, which are 99 aa in length. an in silico sequence analysis shows a premature termination codon in htlv-1 p12i sequences from south american and japanese strains. a translation analysis indicated the presence of 86-aa and 81-aa p12i proteins, shorter than the 99-aa protein found in the majority ... | 2006 | 16706625 |
| t-cell tropism of simian t-cell leukaemia virus type 1 and cytokine profiles in relation to proviral load and immunological changes during chronic infection of naturally infected mandrills (mandrillus sphinx). | although a wide variety of non-human primates are susceptible to simian t-cell leukaemia virus type 1 (stlv-1), little is known about the virological or molecular determinants of natural stlv-1 infection. | 2009 | 19457158 |
| dynamic interaction between stlv-1 proviral load and t-cell response during chronic infection and after immunosuppression in non-human primates. | we used mandrills (mandrillus sphinx) naturally infected with simian t-cell leukemia virus type 1 (stlv-1) as a model for evaluating the influence of natural stlv-1 infection on the dynamics and evolution of the immune system during chronic infection. furthermore, in order to evaluate the role of the immune system in controlling the infection during latency, we induced immunosuppression in the infected monkeys. we first showed that the stlv-1 proviral load was higher in males than in females and ... | 2009 | 19557183 |
| high prevalence, coinfection rate, and genetic diversity of retroviruses in wild red colobus monkeys (piliocolobus badius badius) in tai national park, cote d'ivoire. | simian retroviruses are precursors of all human retroviral pathogens. however, little is known about the prevalence and coinfection rates or the genetic diversity of major retroviruses-simian immunodeficiency virus (siv), simian t-cell lymphotropic virus type 1 (stlv-1), and simian foamy virus (sfv)-in wild populations of nonhuman primates. such information would contribute to the understanding of the natural history of retroviruses in various host species. here, we estimate these parameters for ... | 2010 | 20484508 |
| full-genome characterization of simian t-cell leukemia virus type 1 subtype b from a wild-born captivegorilla gorilla gorillawith t-cell lymphoma. | there are four lineages of primate t-cell lymphocytic viruses (human t-cell lymphocytic virus [htlv]/simian t-cell lymphocytic virus [stlv]), which are further divided into subtypes. to date, there is only one full-length htlv-1 subtype b genome available. here, we report the genome of a new stlv-1 subtype b from a 43-year-old male gorilla with t-cell lymphoma. | 2017 | 29074651 |
| frequent horizontal and mother-to-child transmission may contribute to high prevalence of stlv-1 infection in japanese macaques. | simian t-cell leukemia virus type 1 (stlv-1) is disseminated among various non-human primate species and is closely related to human t-cell leukemia virus type 1 (htlv-1), the causative agent of adult t-cell leukemia and htlv-1-associated myelopathy/tropical spastic paraparesis. notably, the prevalence of stlv-1 infection in japanese macaques (jms) is estimated to be > 60%, much greater than that in other non-human primates; however, the mechanism and mode of stlv-1 transmission remain unknown. ... | 2020 | 32576215 |
| prospects for the management of human t-cell lymphotropic virus type 1-associated myelopathy. | over the twenty-five years since the association of human t-cell lymphotropic virus type 1 infection with tropical spastic paraparesis, little progress has been made in the treatment of this chronic debilitating condition. the purpose of this review is to highlight the most informative results and to identify the most promising candidates for further study. although many small observational studies have been reported, only twice have the positive data been tested in randomized controlled studies ... | 2011 | 21799534 |
| in vivo dynamics and adaptation of htlv-1-infected clones under different clinical conditions. | human t-cell leukemia virus type 1 (htlv-1) spreads through cell contact. therefore, this virus persists and propagates within the host by two routes: clonal proliferation of infected cells and de novo infection. the proliferation is influenced by the host immune responses and expression of viral genes. however, the detailed mechanisms that control clonal expansion of infected cells remain to be elucidated. in this study, we show that newly infected clones were strongly suppressed, and then stab ... | 2021 | 33524072 |
| [human retrovirus htlv-1: descriptive and molecular epidemiology, origin, evolution, diagnosis and associated diseases.] | human t-cell leukemia/lymphoma virus type 1 (htlv-1) was the first oncogenic human retrovirus discovered in 1980. it is estimated that around 10-20 million people are infected with htlv-1 worldwide. however, htlv-1 is not a ubiquitous virus. indeed, htlv-1 is present throughout the world with clusters of high endemicity including mainly southern japan, the caribbean region, parts of south america and intertropical africa, with foci in the middle east and australia. the origin of this puzzling ge ... | 2011 | 21796326 |
| 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 ... | 2011 | 21827287 |
| simian immunodeficiency virus seroreactivity in inhabitants from rural cameroon frequently in contact with non-human primates. | central african tropical forests are home to several species of non-human primates (nhps), infected by simian immunodeficiency virus (siv). it is well-known that hiv-1 epidemic is due to cross-transmission and adaptation of siv to humans. the main goal of this work was to investigate if a nhp bite is a risk factor for siv acquisition. a cross-sectional study was performed in rural cameroon on 246 bitten individuals (mostly by adult nhps), matched, according to sex, age, and ethnicity (bantus and ... | 2017 | 28135660 |
| quantifying transmission by stage of infection in the field: the example of siv-1 and stlv-1 infecting mandrills. | the early stage of viral infection is often followed by an important increase of viral load and is generally considered to be the most at risk for pathogen transmission. most methods quantifying the relative importance of the different stages of infection were developed for studies aimed at measuring hiv transmission in humans. however, they cannot be transposed to animal populations in which less information is available. here we propose a general method to quantify the importance of the early ... | 2015 | 25296992 |
| immunological alterations and associated diseases in mandrills (mandrillus sphinx) naturally co-infected with siv and stlv. | mandrills are naturally infected with simian t-cell leukaemia virus type 1 (stlv-1) and simian immunodeficiency virus (siv)mnd. in humans, dual infection with human immunodeficiency virus (hiv) and human t-cell lymphotropic virus type 1 (htlv-1) may worsen their clinical outcome. we evaluated the effect of co-infection in mandrills on viral burden, changes in t-cell subsets and clinical outcome. the siv viral load was higher in siv-infected mandrills than in co-infected animals, whereas the stlv ... | 2014 | 24725945 |
| new stlv-3 strains and a divergent sivmus strain identified in non-human primate bushmeat in gabon. | human retroviral infections such as human immunodeficiency virus (hiv) or human t-cell lymphotropic virus (htlv) are the result of simian zoonotic transmissions through handling and butchering of non-human primates (nhp) or by close contact with pet animals. recent studies on retroviral infections in nhp bushmeat allowed for the identification of numerous simian immunodeficiency viruses (siv) and simian t-cell lymphotropic viruses (stlv) to which humans are exposed. nevertheless, today, data on ... | 2012 | 22462797 |
| serological and molecular methods to study epidemiological aspects of human t-cell lymphotropic virus type 1 infection. | we estimated that at least 5-10 million individuals are infected with htlv-1. importantly, this number is based on the study of nearly 1.5 billion people living in known human t-cell lymphotropic virus type 1 (htlv-1) endemic areas, for which reliable epidemiological data are available. however, for some highly populated regions including india, the maghreb, east africa, and some regions of china, no consistent data are yet available which prevents a more accurate estimation. thus, the number of ... | 2017 | 28357658 |
| bushmeat hunting and zoonotic transmission of simian t-lymphotropic virus 1 in tropical west and central africa. | simian t-lymphotropic virus 1 (stlv-1) enters human populations through contact with non-human primate (nhp) bushmeat. we tested whether differences in the extent of contact to stlv-1 infected nhp bushmeat foster regional differences in prevalence of human htlv-1. using serological and pcr assays, we screened humans and nhp at two sub-saharan african sites where subsistence hunting was expected to be less (taï region, côte d'ivoire, civ) or more developed (bandundu region, democratic republic of ... | 2017 | 28298599 |
| detailed phylogenetic analysis of primate t-lymphotropic virus type 1 (ptlv-1) sequences from orangutans (pongo pygmaeus) reveals new insights into the evolutionary history of ptlv-1 in asia. | while human t-lymphotropic virus type 1 (htlv-1) originates from ancient cross-species transmission of simian t-lymphotropic virus type 1 (stlv-1) from infected nonhuman primates, much debate exists on whether the first htlv-1 occurred in africa, or in asia during early human evolution and migration. this topic is complicated by a lack of representative asian stlv-1 to infer ptlv-1 evolutionary histories. in this study we obtained new stlv-1 ltr and tax sequences from a wild-born bornean orangut ... | 2016 | 27245152 |
| cellular immune responses against simian t-lymphotropic virus type 1 target tax in infected baboons. | there are currently 5 million to 10 million human t-lymphotropic virus type 1 (htlv-1)-infected people, and many of them will develop severe complications resulting from this infection. a vaccine is urgently needed in areas where htlv-1 is endemic. many vaccines are best tested in nonhuman primate animal models. as a first step in designing an effective htlv-1 vaccine, we defined the cd8(+) and cd4(+) t cell response against simian t-lymphotropic virus type 1 (stlv-1), a virus closely related to ... | 2016 | 26984729 |
| modes of transmission of simian t-lymphotropic virus type 1 in semi-captive mandrills (mandrillus sphinx). | non-human primates (nhps) often live in inaccessible areas, have cryptic behaviors, and are difficult to follow in the wild. here, we present a study on the spread of the simian t-lymphotropic virus type 1 (stlv-1), the simian counterpart of the human t-lymphotropic virus type 1 (htlv-1) in a semi-captive mandrill colony. this study combines 28 years of longitudinal monitoring, including behavioral data, with a dynamic mathematical model and bayesian inference. three transmission modes were susp ... | 2015 | 26143560 |
| a severe bite from a nonhuman primate is a major risk factor for htlv-1 infection in hunters from central africa. | htlv-1 infection is endemic to central african populations. the risk factors for htlv-1 acquisition in humans via the interspecies transmission of stlv-1 (its simian counterpart) remain largely unknown. | 2015 | 25722199 |
| origin of htlv-1 in hunters of nonhuman primates in central africa. | of 78 gabonese individuals who had received bites from nonhuman primates (nhps) while hunting, 7 were infected with human t lymphotropic virus (htlv-1). five had been bitten by gorillas and were infected with subtype b strains; however, a 12-year-old girl who was severely bitten by a cercopithecus nictitans was infected with a subtype d strain that was closely related to the simian t lymphotropic virus (stlv-1) that infects this monkey species. her mother was infected with a subtype b strain. th ... | 2015 | 25147276 |
| delayed seroconversion to stlv-1 infection is associated with mutations in the pol and rex genes. | simian t-cell lymphoma/leukemia virus-1 (stlv-1) infection of non-human primates can serve as a model for human t-cell lymphoma/leukemia virus infection. | 2013 | 24025129 |
| origin of human t-lymphotropic virus type 1 in rural côte d'ivoire. | simian t-lymphotropic virus type 1 (stlv-1) strains occasionally infect humans. however, the frequency of such infections is unknown. we show that direct transmission of stlv-1 from nonhuman primates to humans may be responsible for a substantial proportion of human t-lymphotropic virus type 1 infections in rural côte d'ivoire, where primate hunting is common. | 2012 | 22516514 |
| the ecology of primate retroviruses - an assessment of 12 years of retroviral studies in the taï national park area, côte d׳ivoire. | the existence and genetic make-up of most primate retroviruses was revealed by studies of bushmeat and fecal samples from unhabituated primate communities. for these, detailed data on intra- and within-species contact rates are generally missing, which makes identification of factors influencing transmission a challenging task. here we present an assessment of 12 years of research on primate retroviruses in the taï national park area, côte d'ivoire. we discuss insights gained into the prevalence ... | 2014 | 25010280 |
| simian t-cell lymphotropic virus type i alters the proviral load and biodistribution of simian retrovirus type 2 in co-infected macaques, supporting advancement of immunosuppressive pathology. | the infection dynamics and pathology of a retrovirus may be altered by one or more additional viruses. to investigate this further, this study characterized proviral load, biodistribution and the immune response in macaca fascicularis naturally infected with combinations of simian retrovirus type 2 (srv-2) and simian t-cell lymphotropic virus type i (stlv-i). as the mesenteric lymph node (mln) and the spleen have been implicated previously in response to retroviral infection, the morphology and ... | 2013 | 23197576 |
| low rates of transmission of srv-2 and stlv-i to juveniles in a population of macaca fascicularis facilitate establishment of specific retrovirus-free colonies. | prevalence of simian retrovirus-2 (srv-2) and simian t lymphotropic virus type i (stlv-i), was unknown in 337 captive cynomolgus macaques. | 2009 | 19320800 |
| spontaneous and experimental malignancies in non-human primates. | contrary to earlier established opinion that tumors in monkeys are found rarely, now the large material confirms that monkey tumors are frequent phenomenon. tumor incidence clearly increases with age. frequencies of benign and malignant tumors of various locations and histogenesis are slightly different. tumors of hematopoietic system are the most frequent. sporadic cases and enzootic outbreaks of lymphomas are described for different kinds of monkeys, including apes, and probably are caused by ... | 2014 | 24392944 |
| simian t-lymphotropic virus-associated lymphoma in 2 naturally infected baboons: t-cell clonal expansion and immune response during tumor development. | two young female baboons naturally infected with simian t-lymphotropic virus type 1 (stlv1) were euthanized due to chronic respiratory disease that was unresponsive to treatment. massive lymphocytic infiltration of the lung interstitium suggested a diagnosis of stlv-associated lymphoma. in each case, the diagnosis was confirmed through inverse pcr (ipcr) that detected monoclonally integrated stlv1 provirus in cellular dna extracted from lymphoma tissue and peripheral blood cells (pbc). one domin ... | 2013 | 23759532 |
| spontaneous malignant lymphoma and leukemia in a simian t-lymphotropic virus type i (stlv-i) antibody positive olive baboon. | | 1990 | 2153868 |
| stlv-1 infection of papio anubis: tax sequence heterogeneity and t cell recognition. | natural infection of baboons with simian t lymphotropic virus (stlv) is a potentially useful model system for study of vaccination against the human virus htlv. here we expand the number of available full-length stlv-1 baboon sequences from one to three and relate t cell responses that recognize the immunodominant tax protein to the tax sequences present in two individual baboons. continuously growing t cell lines were established from two baboons, 12141 and 12752. next-generation sequencing (ng ... | 2017 | 28724769 |
| absence of accessory genes in a divergent simian t-lymphotropic virus type 1 isolated from a bonnet macaque (macaca radiata). | primate t-lymphotropic viruses type 1 (ptlv-1) are complex retroviruses infecting both human (htlv-1) and simian (stlv-1) hosts. they share common epidemiological, clinical and molecular features. in addition to the canonical gag, pol, env retroviral genes, ptlv-1 purportedly encodes regulatory (i.e. tax, rex, and hbz) and accessory proteins (i.e. p12/8, p13, p30). the latter have been found essential for viral persistence in vivo. | 2019 | 31283766 |
| nonhuman primate retroviruses from cambodia: high simian foamy virus prevalence, identification of divergent stlv-1 strains and no evidence of siv infection. | nonhuman primates (nhps) carry retroviruses such as simian immunodeficiency viruses (siv), simian t-cell lymphotropic viruses (stlv) and simian foamy viruses (sfv). here, we revisited nhps from cambodia to assess the prevalence and diversity of these retroviruses using updated viral detection tools. we screened blood from 118 nhps consisting of six species (macaca fascicularis (n=91), macaca leonine (n=8), presbytis cristata (n=3), nycticebus coucang (n=1), hylobates pileatus (n=14), and pongo p ... | 2013 | 23612320 |