| multiple isolates and characteristics of human t-cell leukemia virus type ii. | human t-cell leukemia (or lymphotropic) virus type ii (htlv-ii) was isolated from eight htlv-seropositive patients, six of whom were also infected with human immunodeficiency virus, by cocultivation of peripheral blood mononuclear cells (pbmcs) with bjab, a continuous b-cell line. restriction endonuclease mapping of the proviruses demonstrated consistent differences among isolates, and two distinct physical map patterns were observed. the results suggest the existence of two closely related mole ... | 1992 | 1347796 |
| transformation of animal cells with human t-cell leukemia virus type ii. | human t-cell leukemia virus type ii (htlv-ii) was tested for its ability to transform normal animal cells. the htlv-ii-infected human t-cell line, htlv-iia was lethally x-irradiated and cocultivated with normal leukocytes of rabbit and crab-eating monkey and spleen cells of hamster. the transformed cell lines, designated ra-iia, si-iia and ham-iia, were established. these cell lines were shown to be infected with htlv-ii by the polymerase chain reaction method combined with the digoxigenin-enzym ... | 1990 | 2118885 |
| detection of provirus in an htlv-ii producer cd8+ t cell line by polymerase chain reaction combined with digoxigenin-elisa method. | a human t-cell leukemia virus type ii (htlv-ii) producer cell line, designated htlv-iia, was established by cocultivation with leukocytes from an anti-human t-cell leukemia type i (htlv-i) antibody-positive white male intravenous drug abuser and a healthy japanese female. the cell line was examined for viral antigens by the indirect immunofluorescence method. the cytoplasm of over 80% of the cells was brilliantly stained. cytogenetically, the cell line has a normal female karyotype. electron mic ... | 1990 | 2142150 |
| genotypic characteristics of htlv-ii isolates from amerindian and non-indian populations. | the amerindian human t-cell lymphotropic virus type ii isolate htlv-iig12 has been demonstrated to be an htlv-iib with several unique features, including several restriction enzyme site changes, a distinctive pre-gag region, a stop codon within the pol gene, and an extended tax protein. in this study, htlv-ii isolates from amerindian and non-indian populations were characterized by restriction enzyme site analysis to determine the prevalent htlv-ii subtype. in addition, dna amplification by the ... | 1995 | 7483286 |
| identification of human t cell lymphotropic virus type iia infection in the kayapo, an indigenous population of brazil. | human t cell lymphotropic virus type ii (htlv-ii) infection is endemic in a number of indigenous populations in north, central, and south america. in the present study we have employed serological and molecular methods to identify htlv-ii infection in indian communities in the amazon region of brazil. sera (1324) from 25 different indian communities were analyzed by elisa and western blot. one hundred and four samples (7.8%) from a number of culturally distinct and geographically unrelated popul ... | 1995 | 7546908 |
| nucleotide sequence and restriction fragment length polymorphism analysis of the long terminal repeat of human t cell leukemia virus type ii. | molecular studies have demonstrated the existence of two major subtypes of human t cell leukemia virus type ii: htlv-iia and htlv-iib. in attempts to further classify this family of viruses we have carried out nucleotide sequence and restriction fragment length polymorphism (rflp) analysis of the long terminal repeat (ltr), a region that has been shown in previous studies to have the greatest intra- and intersubtype genomic divergence. analysis of the nucleotide sequences suggested the existence ... | 1995 | 7576919 |
| identification of iia and iib molecular subtypes of human t-cell lymphotropic virus type ii among italian injecting drug users. | the molecular characterization of two human t-cell lymphotropic virus type ii (htlv-ii) isolates, gu and va, obtained from italian injecting drug users (idus) has indicated that these isolates belong to the htlv-iib subtype. to establish whether italian idus are also infected by the htlv-iia variant, sequencing of the gp21 env gene of proviral dna from further patients was carried out. two new isolates, bo and md, were found, which presented a divergence of 0.4-0.7% from the iia prototype htlv-i ... | 1995 | 7697450 |
| a rapid and sensitive method of identification of htlv-ii subtypes. | there are 2 subtypes of human t-cell lymphoma/leukemia virus type ii (htlv-ii), a and b. htlv-ii is increasingly associated with rare forms of lymphocytic neoplasia and a neurodegenerative disorder, characterized by hyperspasticity and ataxia. we have used pcr to amplify, clone and sequence 140 bp of the pol gene from many isolates of htlv-iia and htlv-iib from around the world. analysis of these and other published sequence established that all htlv-iia sequences contained a unique hinf i site ... | 1995 | 7714483 |
| phylogenetic relationship and geographic distribution of multiple human t-cell lymphotropic virus type ii subtypes. | the current env-based subtyping of human t-cell lymphotropic virus type ii (htlv-ii) identifies only two heterogenetic groups, htlv-iia and htlv-iib. to better understand the genetic diversity and phylogeny of htlv-ii, we examined the most divergent genomic region of htlv-ii, the long terminal repeat, by using restriction fragment length polymorphism (rflp) and sequence analysis. long terminal repeat sequences were amplified from peripheral blood mononuclear cells by pcr and digested with seven ... | 1995 | 7815525 |
| isolation and genomic analysis of human t lymphotropic virus type ii from ghana. | an htlv-ii was isolated from a ghanaian female patient with arc and anti-htlv-ii antibody by cocultivation of pbmc with molt-4 cells. a part of the 5' ltr of this virus was sequenced. sequence homology between this virus and the corresponding sequence of mo, the prototype of htlv-ii, is 97.4%. furthermore, this virus is a member of the htlv-iia group, which was proposed by hall et al. this is the first report of an htlv-ii sequence from africa confirmed not only by serological evidence, but also ... | 1993 | 7904168 |
| characterization of human t-lymphotropic virus type i- and ii-infected t-cell lines: antigenic, phenotypic, and genotypic analysis. | eighteen long-term t-cell lines were established from peripheral blood mononuclear cells of individuals infected with human t-lymphotropic virus type i (htlv-i) or ii (htlv-ii). these cell lines (10 htlv-i and 8 htlv-ii), representing diverse pathologic profiles and geographic regions, have been in culture for over 6 months and have constitutively produced p24gag antigen. antigenic characterization of the cell lines by western blot analysis demonstrated that all but one produced gag (p24) and en ... | 1993 | 8105609 |
| human t lymphotropic virus type ii (htlv-ii) infection among female prostitutes in yucatan, mexico. | the antibodies to human t-lymphotropic virus type i/ii (htlv-i/ii) were determined in non-intravenous drug-using female prostitutes from merida yucatan, mexico. serum specimens from 282 female prostitutes collected during 1990 were tested initially by enzyme immunoassay and further confirmed by western blot assays. of these, 5 (1.8%, 95% confidence interval 0.2 to 3.3) were shown to be htlv-i/ii positive (reactivity to p24gag and gp68/r21eenv). all five specimens were shown to be infected with h ... | 1993 | 8213887 |
| nucleotide sequence analysis of human t cell leukemia virus, type ii (htlv-ii) isolates. | a study by hall et al. (j virol 1992;66:2456-2463; ref. 11) has suggested the existence of two closely related molecular subtypes of htlv-ii, which were tentatively designated htlv-iia and htlv-iib. to confirm this nucleotide sequence analysis of 986 bp of the env gene region encoding the entire surface glycoprotein, gp46, and the amino terminus of the transmembrane glycoprotein, gp21, of 10 htlv-ii isolates was carried out. the results clearly established the existence of two subtypes and demon ... | 1993 | 8217342 |
| identification and characterization of an extended tax protein in human t-cell lymphotropic virus type ii subtype b isolates. | the tax gene sequence of human t-cell lymphotropic virus type ii isolate g12 (htlv-iig12) was found to encode an extended tax protein when compared with that of htlv-iimot. in vitro transcription-translation of the htlv-iig12 tax gene produced a 40-kda tax protein that specifically reacted with serum specimens from htlv-ii-infected individuals. limited sequence analysis demonstrated that isolates with an extended tax protein were all htlv-ii subtype b (htlv-iib). therefore, the extended tax prot ... | 1993 | 8230487 |
| identification of human t cell leukemia virus type iib infection in the wayu, an aboriginal population of colombia. | human t cell leukemia virus type ii (htlv-ii) is endemic in a number of native american populations and high rates of infection have also been demonstrated in intravenous drug abusers (ivdas). studies of virus isolates in the latter population have shown the existence of two closely related subtypes of the virus, htlv-iia and htlv-iib. to characterize the viruses present in native americans, we analyzed by nucleotide sequence analysis the proviruses from the wayu, an aboriginal population residi ... | 1993 | 8294210 |
| endemic human t cell leukemia virus type ii infection in southwestern us indians involves two prototype variants of virus. | human t cell leukemia virus (htlv) type ii is endemic in certain american indians, and high rates of infection occur in intravenous drug users (ivdus). north american ivdus are infected with two distinct variants, htlv-iia and -iib. if ivdus became infected as a result of interaction with members of an american indian population, both viral forms should be demonstrable in such populations. nucleotide sequence analysis of 630 bases of the env gene encoding the gp21 protein was done on dna from 12 ... | 1993 | 8354915 |
| molecular analysis of human t-cell lymphotropic virus type ii from wayuu indians of colombia demonstrates two subtypes of htlv-iib. | studies of the genetic heterogeneity of human t-cell lymphotropic virus type ii (htlv-ii) have revealed the presence of two genetic subtypes, termed htlv-iia and htlv-iib. the htlv-iib subtype encodes an immunodominant epitope present at the c-terminus of the extended tax protein and, by using an ltr-based, restriction fragment-length polymorphism (rflp) assay, can be further classified into iib60-iib5, with htlv-iib1 (central amerindian-like) and htlv-iib5 (north amerindian-like) being characte ... | 1995 | 8560775 |
| genetic variants of human t-lymphotrophic virus type ii in american indian groups. | the human t-lymphotropic virus type ii (htlv-ii) is found in many new world indian groups in north and south america and may have entered the new world from asia with the earliest migration of ancestral amerindians over 15,000 years ago. to characterize the phylogenetic relationships of htlv-ii strains infecting geographically diverse indian populations, we used polymerase chain reaction to amplify htlv-ii sequences from lymphocytes of seropositive amerindians from brazil (kraho, kayapo, and kax ... | 1996 | 8614983 |
| [nucleotide sequence and restriction fragment length polymorphism (rflp) analysis of the long terminal repeat of human t-cell lymphotropic virus type ii (htlv-ii)]. | molecular studies have demonstrated the existence of two major subtypes of human t-cell lymphotropic virus type ii, htlv-iia and htlv-iib. in attempts to further classify this family of viruses we have carried out nucleotide sequence and restriction fragment length polymorphism (rflp) analysis of the long terminal repeat (ltr), a region which has been shown in previous studies to have the greatest intra-and inter-subtype genomic divergence. analysis of the nucleotide sequences suggested the exis ... | 1996 | 8641678 |
| complete nucleotide sequence of the italian human t-cell lymphotropic virus type ii isolate gu and phylogenetic identification of a possible origin of south european epidemics. | the complete nucleotide sequence of a human t-cell lymphotropic virus type ii isolate (htlv-ii-gu) from an italian injecting drug user was obtained, representing the first entire sequence of a european htlv-ii isolate. the htlv-ii-gu genome was more similar to the htlv-iib-nra isolate (98.4%) and htlv-iib-g12 (98.2%) than to htlv-iia-mo (95.2%). the classification of htlv-ii-gu as subtype iib was confirmed by restriction analysis. just as for htlv-iia strain mo, htlv-iib-gu cultured lymphocytes ... | 1996 | 8683207 |
| endemicity and phylogeny of the human t cell lymphotropic virus type ii subtype a from the kayapo indians of brazil: evidence for limited regional dissemination. | long terminal repeat (ltr)-based restriction fragment length polymorphism (rflp) analysis of human t cell lymphotropic virus type ii (htlv-ii) from 17 seropositive kayapo indians from brazil showed that all 17 samples contained a unique htlv-iia subtype (a-ii). additional rflp screening demonstrated the presence of this subtype in two of three brazilian blood donors and a mexican prostitute and her child. in contrast, 129 samples from blood donors and intravenous drug users (idus) from the unite ... | 1996 | 8743089 |
| the phylogeny and molecular epidemiology of human t-cell lymphotropic virus type ii. | phylogenetic analysis of long terminal repeat (ltr) sequences from 29 human t-cell lymphotropic virus type ii (htlv-ii) strains from endemic and nonendemic populations led to the proposition of three htlv-iia phylogroups (a-i, a-ii, and a-iii) and four htlv-iib phylogroups (b-i, b-ii, b-iii, b-iv). b-i and b-ii represented sequences from u.s. and european intravenous drug users, and b-iv included amerindian sequences from the guaymi and wayuu. interestingly, sequences from an african pygmy and s ... | 1996 | 8797729 |
| malignant lymphoma induction in rabbits by intravenous inoculation of epstein-barr-virus-related herpesvirus from htlv-ii-transformed cynomolgus leukocyte cell line (si-iia). | malignant lymphomas, which were usually of t-cell type, were induced in 10 of 13 (77%) male rabbits (japanese white, 8/10; new zealand white, 2/3) inoculated i.v. with htlv-ii-transformed simian (cynomolgus) leukocyte cell line (si-iia) cells. of 7 rabbits injected with cell-free pellets from si-iia cultures, 5 also developed malignant lymphoma (15-28 days). lymphoma development was completely inhibited by inactivation of cell-free pellets from si-iia culture with ethyl ether and was almost supp ... | 1995 | 8847148 |
| nucleotide sequence and restriction fragment-length polymorphism analysis of human t-cell lymphotropic virus type ii (htlv-ii) in southern europe: evidence for the htlv-iia and htlv-iib subtypes. | human t-cell lymphotropic virus type ii (htlv-ii) has been subtyped into two major groups, iia and iib, according to molecular studies involving env gene sequencing. subsequently, this retrovirus was further subclassified by examining the long terminal repeat (ltr), the most divergent genomic region. sequence analysis and restriction fragment-length polymorphism (rflp) applied to the ltr region identified either four or five groups within the iia subtype (depending on the restriction enzyme sets ... | 1996 | 8948378 |
| comparative performances of enzyme-linked immunosorbent, western blot, and polymerase chain reaction assays for human t-lymphotropic virus type ii infection that is endemic among indians of the gran chaco region of south america. | human t-cell lymphoma/leukemia viruses types i and ii (htlv-i and htlv-ii) are related exogenous human retroviruses. the former is definitely pathogenic while disease association with the latter is unclear. there are two subtypes of htlv-ii, a and b. currently, enzyme-linked immunosorbent assays (elisas) based on htlv-i antigens are used to screen for the presence of htlv-i and -ii antibodies. confirmation and subtyping are accomplished by western blot (wb) or elisas based on htlv-i whole viral ... | 1997 | 9024490 |
| nucleotide sequence variation of human t-lymphotropic virus type ii in vietnam. | a high rate of human t-lymphotropic virus type ii (htlv-ii) infection has been documented in intravenous drug abusers (ivdas) in south vietnam. we have investigated the molecular characteristics of the virus and have shown that one htlv-ii subtype is predominant in ho chi minh city. this molecular subtype, htlv-iib, was identified in a number of south vietnamese by nucleotide sequence analysis of the long terminal repeat (ltr) region. htlv-iia was not found. these findings suggest that htlv-iib ... | 1997 | 9369924 |
| evolutionary rate and genetic heterogeneity of human t-cell lymphotropic virus type ii (htlv-ii) using isolates from european injecting drug users. | seven new italian and two new british htlv-ii isolates were obtained from injecting drug users and the entire long terminal repeat (ltr) region was sequenced. restriction analysis showed that all the italian isolates are of the iib subtype, whereas the british isolates are of the iia subtype. to understand whether the further differentiation of each two principal htlv-ii subtypes in several subgroups could be statistically supported by phylogenetic analysis, the neighbor-joining, parsimony, and ... | 1998 | 9545470 |
| identification and molecular characterization of human t lymphotropic virus type ii infections in intravenous drug abusers in the former south vietnam. | previous serological studies have demonstrated that some 60% of intravenous drug abusers (ivdas) in urban areas of the former south vietnam are infected with htlv-ii. in the present report we have attempted to characterize the viruses using restriction fragment length polymorphism (rflp) and nucleotide sequence analysis of the provirus long terminal repeat (ltr) region. rflp analysis of nine samples demonstrated that all were infected with the htlv-iib subtype. the htlv-iia subtype was not detec ... | 1998 | 9566557 |
| detection of htlv-iia blood donors in an urban area of the amazon region of brazil (belém, pa). | the human lymphotropic viruses type i (htlv-i) and type ii (htlv-ii) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. htlv-i is endemic in a number of different geographical areas and is associated with several clinical disorders. htlv-ii is endemic in several indian groups of the americas and intravenous drug abusers in north and south america, europe and southeast asia. during the year of 1995, all ... | 1998 | 9608238 |
| high rate of human t lymphotropic virus type iia infection in hiv type 1-infected intravenous drug abusers in ireland. | serological and molecular analyses of a cohort of hiv-1-infected intravenous drug abusers (ivdas) (n = 103) in dublin, ireland have demonstrated that 15 of 103 (14.6%) were infected with htlv-ii, which is the highest infection rate yet recorded for any european country. restriction fragment length polymorphism (rflp) analysis of the env region of the provirus demonstrated that the infection involved only the htlv-iia subtype; the htlv-iib subtype was not detected. phylogenetic analysis of the nu ... | 1999 | 10357465 |
| isolation, cloning, and complete nucleotide sequence of a phenotypically distinct brazilian isolate of human t-lymphotropic virus type ii (htlv-ii). | analysis of human t-lymphotropic virus type ii (htlv-ii) isolates from north america and europe have demonstrated the existence of two molecular subtypes of the virus, htlv-iia and htlv-iib. recently, studies on htlv-ii infections in brazil have revealed isolates that are related phylogenetically to the htlv-iia subtype but have a htlv-iib phenotype with respect to the transactivating protein, tax. to more clearly define this relationship, htlv-ii was isolated from peripheral blood of an ivda fr ... | 2000 | 10814579 |
| htlv-ii infection associated with a chronic neurodegenerative disease: clinical and molecular analysis. | htlv ii is a retrovirus endemic in some amerindian tribes and spread worldwide with a high prevalence among intravenous drug abusers. it has three different genetic subtypes a, b, and d, defined mainly by the long terminal repeat (ltr) region. htlv ii has been associated with a neurodegenerative disease in few cases. we describe the first well-documented case in brazil where the virus is endemic in isolated ethnic groups. the patient is a 55-year-old woman with a chronic and painful syndrome cha ... | 2002 | 11782936 |
| comparison of creb- and nf-kappab-mediated transactivation by human t lymphotropic virus type ii (htlv-ii) and type i (htlv-i) tax proteins. | the function of the transactivator protein tax from htlv-ii subtype a, subtype b, brazilian subtype c, and african subtype d isolates was compared to that of tax from an htlv-i isolate. htlv-ii subtypes a, b, and c were less active in the transactivation of a nf-kappab reporter compared to htlv-i tax in 293t but not jurkat t cells. in both cell types there were no significant differences between the functions of htlv-ii b, c, and d and htlv-i tax proteins on either a full-length htlv-i ltr or a ... | 2002 | 12033776 |
| molecular epidemiology of human t-lymphotropic virus type ii infection in amerindian and urban populations of the amazon region of brazil. | molecular characterization of human t-cell lymphotropic virus ii (htlv-ii) isolates in north america and europe has shown the existence of two principal subtypes of the virus, htlv-iia and htlv-iib. subsequent studies on htlv-ii isolates from brazil have suggested the existence of a unique variant phylogenetically related to htlv-iia but phenotypically similar to htlv-iib with respect to the transactivatory protein, tax. this variant has been designated htlv-iic. to better clarify the variabilit ... | 2002 | 12495078 |
| molecular evidence of htlv-ii subtype b among an urban population living in south brazil. | human t cell lymphotropic virus type ii (htlv-ii) is a deltaretrovirus endemic in indian populations living in central and south america, among pygmies tribes from central africa, and epidemic among injecting drug users (idus) in the united states, europe, southeast asia, and south america. to date only the htlv-iia subtype has been demonstrated among brazilians (amazon basin indians, blood donors, and idus). we analyzed htlv-ii isolates from 12 individuals living in the urban area of porto aleg ... | 2006 | 16623631 |
| molecular characterization of human t-cell lymphotropic virus type 2 (htlv-ii) from people living in urban areas of sao paulo city: evidence of multiple subtypes circulation. | background: in brazil, human t-cell lymphotropic virus type i and type ii (htlv-i and htlv-ii) are co-circulating and possess approximately 65% homology, which results in high cross-reactivity in serological tests. based on the detection of eia and western blot (wb) tests, htlv serodiagnosis yields indeterminate results in high-risk population, with the true determination of htlv-ii prevalence requiring a combined serological and molecular analysis. molecular analysis of htlv-ii isolates has sho ... | 2007 | 17177305 |
| human t cell lymphotropic virus type 2a strains among hiv type 1-coinfected patients from brazil have originated mostly from brazilian amerindians. | the human t cell lymphotropic virus type 2 (htlv-2) is found mainly in amerindians and in intravenous drug users (idus) from urban areas of the united states, europe, and latin america. worldwide, htlv-2a and htlv-2b subtypes are the most prevalent. phylogenetic analysis of htlv-2 isolates from brazil showed the htlv-2a subtype, variant -2c, which spread from indians to the general population and idus. the present study searched for the types of htlv-2 that predominate among hiv-1-coinfected pat ... | 2013 | 23484539 |