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1.
The human T-lymphotropic retrovirus HTLV-III/LAV encodes a trans-activator that increases viral gene expression. We expressed this trans-activator in animal cells and studied its structural and functional characteristics. The putative trans-activator protein was immunoprecipitated from overproducing stable cell lines and shown to migrate as a 14-kilodalton polypeptide on sodium dodecyl sulfate-polyacrylamide gels. S1 nuclease mapping experiments showed that the trans-activator increases the levels of steady-state messenger RNA transcribed from the viral long terminal repeat promoter. Sequences within the R region of the HTLV-III/LAV long terminal repeat are essential for trans-activation. Quantitations of messenger RNA and protein showed that the protein increase was greater than the messenger RNA increase in CV1 and HeLa cells, indicating that more than one mechanism was responsible for the trans-activation and that cell type-specific factors may determine the final level of trans-activation. 相似文献
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Characterization of long terminal repeat sequences of HTLV-III 总被引：30，自引：0，他引：30
B Starcich L Ratner S F Josephs T Okamoto R C Gallo F Wong-Staal 《Science (New York, N.Y.)》1985,227(4686):538-540
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W Wachsman A J Cann J L Williams D J Slamon L Souza N P Shah I S Chen 《Science (New York, N.Y.)》1987,235(4789):674-677
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Induction of HTLV-III/LAV from a nonvirus-producing T-cell line: implications for latency 总被引：42，自引：0，他引：42
T Folks D M Powell M M Lightfoote S Benn M A Martin A S Fauci 《Science (New York, N.Y.)》1986,231(4738):600-602
When the human T-cell line A3.01 is infected with HTLV-III/LAV, the virus associated with the acquired immune deficiency syndrome (AIDS), most of the cells are killed. However, a small number of cells that lack the Leu-3 surface marker survive. Under normal conditions these surviving cells do not produce virus, nor can they be infected by the virus, but they can be induced to produce virus by treatment with 5-iodo-2'-deoxyuridine. This response can be induced for as long as 3 months after the initial infection, suggesting that the cells may harbor a latent form of HTLV-III/LAV. 相似文献
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Antibodies reactive with human T-lymphotropic retroviruses (HTLV-III) in the serum of patients with AIDS 总被引：125，自引：0，他引：125
M G Sarngadharan M Popovic L Bruch J Schüpbach R C Gallo 《Science (New York, N.Y.)》1984,224(4648):506-508
In cats, infection with T-lymphotropic retroviruses can cause T-cell proliferation and leukemia or T-cell depletion and immunosuppression. In humans, some highly T4 tropic retroviruses called HTLV-I can cause T-cell proliferation and leukemia. The subgroup HTLV-II also induces T-cell proliferation in vitro, but its role in disease is unclear. Viruses of a third subgroup of human T-lymphotropic retroviruses, collectively designated HTLV-III, have been isolated from cultured cells of 48 patients with acquired immunodeficiency syndrome (AIDS). The biological properties of HTLV-III and immunological analyses of its proteins show that this virus is a member of the HTLV family, and that it is more closely related to HTLV-II than to HTLV-I. Serum samples from 88 percent of patients with AIDS and from 79 percent of homosexual men with signs and symptoms that frequently precede AIDS, but from less than 1 percent of heterosexual subjects, have antibodies reactive against antigens of HTLV-III. The major immune reactivity appears to be directed against p41, the presumed envelope antigen of the virus. 相似文献
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Infection of HTLV-III/LAV in HTLV-I-carrying cells MT-2 and MT-4 and application in a plaque assay 总被引：120，自引：0，他引：120
The human T-cell lines MT-2 and MT-4 carry the human T-cell leukemia virus type I (HTLV-I). When MT-2 and MT-4 were infected with HTLV-III, the probable etiologic agent of the acquired immune deficiency syndrome (AIDS), rapid cytopathogenic effects and cytotoxicity were observed that made it possible to titrate the biologically active virus in a plaque-forming assay. The cytopathogenic effects were preceded by the rapid induction and increase of HTLV-III antigens as revealed by immunofluorescence and immunoprecipitation. Activities of HTLV-III were neutralized by the human antibodies against the virus when immunofluorescence and plaque assays were used. Essentially the same results were obtained with the lymphadenopathy-associated virus (LAV1). 相似文献
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Antigens encoded by the 3'-terminal region of human T-cell leukemia virus: evidence for a functional gene 总被引：47，自引：0，他引：47
T H Lee J E Coligan J G Sodroski W A Haseltine S Z Salahuddin F Wong-Staal R C Gallo M Essex 《Science (New York, N.Y.)》1984,226(4670):57-61
Antibodies in sera from patients with adult T-cell leukemia-lymphoma or from healthy carriers of type I human T-cell leukemia virus (HTLV) recognize an antigen of approximately 42 kilodaltons (p42) in cell lines infected with HTLV-I. Radiolabel sequence analysis of cyanogen bromide fragments of p42 led to the conclusion that this antigen is encoded in part by LOR, a conserved portion of the "X" region that is flanked by the envelope gene and the 3' long terminal repeat of HTLV-I. It is possible that this novel product mediates the unique transformation properties of the HTLV family. 相似文献
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Trans-activator gene of human T-lymphotropic virus type III (HTLV-III) 总被引：204，自引：0，他引：204
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cis- and trans-acting transcriptional regulation of visna virus 总被引：23，自引：0，他引：23
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Isolation of a new virus, HBLV, in patients with lymphoproliferative disorders 总被引：116，自引：0，他引：116
S Z Salahuddin D V Ablashi P D Markham S F Josephs S Sturzenegger M Kaplan G Halligan P Biberfeld F Wong-Staal B Kramarsky 《Science (New York, N.Y.)》1986,234(4776):596-601
A novel human B-lymphotropic virus (HBLV) was isolated from the peripheral blood leukocytes of six individuals: two HTLV-III seropositive patients from the United States (one with AIDS-related lymphoma and one with dermatopathic lymphadenopathy), three HTLV-III seronegative patients from the United States (one with angioimmunoblastic lymphadenopathy, one with cutaneous T-cell lymphoma, and one with immunoblastic lymphoma), and one HTLV-III seronegative patient with acute lymphocytic leukemia from Jamaica. All six isolates were closely related by antigenic analysis, and sera from all six virus-positive patients reacted immunologically with each virus isolate. In contrast, only four sera from 220 randomly selected healthy donors and none from 12 AIDS patients without associated lymphoma were seropositive. The virus selectively infected freshly isolated human B cells and converted them into large, refractile mono- or binucleated cells with nuclear and cytoplasmic inclusion bodies. HBLV is morphologically similar to viruses of the herpesvirus family but is readily distinguishable from the known human and nonhuman primate herpesviruses by host range, in vitro biological effects, and antigenic features. 相似文献
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Detection, isolation, and continuous production of cytopathic retroviruses (HTLV-III) from patients with AIDS and pre-AIDS 总被引：450，自引：0，他引：450
A cell system was developed for the reproducible detection of human T-lymphotropic retroviruses (HTLV family) from patients with the acquired immunodeficiency syndrome (AIDS) or with signs or symptoms that frequently precede AIDS (pre-AIDS). The cells are specific clones from a permissive human neoplastic T-cell line. Some of the clones permanently grow and continuously produce large amounts of virus after infection with cytopathic (HTLV-III) variants of these viruses. One cytopathic effect of HTLV-III in this system is the arrangement of multiple nuclei in a characteristic ring formation in giant cells of the infected T-cell population. These structures can be used as an indicator to detect HTLV-III in clinical specimens. This system opens the way to the routine detection of HTLV-III and related cytopathic variants of HTLV in patients with AIDS or pre-AIDS and in healthy carriers, and it provides large amounts of virus for detailed molecular and immunological analyses. 相似文献
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Suramin protection of T cells in vitro against infectivity and cytopathic effect of HTLV-III 总被引：24，自引：0，他引：24
H Mitsuya M Popovic R Yarchoan S Matsushita R C Gallo S Broder 《Science (New York, N.Y.)》1984,226(4671):172-174
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Expression of the pX gene of HTLV-I: general splicing mechanism in the HTLV family 总被引：43，自引：0，他引：43
Human T-cell leukemia virus type I (HTLV-I) is an etiological agent of adult T-cell leukemia. A viral gene pX encodes for p40X and it has been proposed that this protein trans-activates the viral long terminal repeat and possibly some cellular genes; this activation may be associated with T-cell transformation. The mechanism of pX gene expression and the primary structure of p40X are now reported. Two-step splicing generates the 2.1-kilobase pX mRNA; the initiator methionine for env becomes part of the pX protein. These splicing signals are conserved among all members of the HTLV family except for the acquired immune deficiency syndrome-associated viruses. 相似文献
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Human immunodeficiency virus type 1 (HIV-1) gene expression is activated by Tat, a virally encoded protein. Tat trans-activation requires viral (trans-activation--responsive; TAR) RNA sequences located in the R region of the long terminal repeat (LTR). Existing evidence suggests that Tat probably cooperates with cellular factors that bind to TAR RNA in the overall trans-activation process. A HeLa complementary DNA was isolated and characterized that encodes a TAR RNA-binding protein (TRBP). TRBP activated the HIV-1 LTR and was synergistic with Tat function. 相似文献
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G M Shaw M E Harper B H Hahn L G Epstein D C Gajdusek R W Price B A Navia C K Petito C J O'Hara J E Groopman 《Science (New York, N.Y.)》1985,227(4683):177-182
Unexplained debilitating dementia or encephalopathy occurs frequently in adults and children with the acquired immune deficiency syndrome (AIDS). Brains from 15 individuals with AIDS and encephalopathy were examined by Southern analysis and in situ hybridization for the presence of human T-cell leukemia (lymphotropic) virus type III (HTLV-III), the virus believed to be the causative agent of AIDS. HTLV-III DNA was detected in the brains of five patients, and viral-specific RNA was detected in four of these. In view of these findings and the recent demonstration of morphologic and genetic relatedness between HTLV-III and visna virus, a lentivirus that causes a chronic degenerative neurologic disease in sheep, HTLV-III should be evaluated further as a possible cause of AIDS encephalopathy. 相似文献
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Sequence homology and morphologic similarity of HTLV-III and visna virus, a pathogenic lentivirus 总被引：59，自引：0，他引：59
M A Gonda F Wong-Staal R C Gallo J E Clements O Narayan R V Gilden 《Science (New York, N.Y.)》1985,227(4683):173-177
A study was conducted of the genetic relation between human T-cell lymphotropic retroviruses and visna virus. The human T-cell lymphotropic viruses include those associated with T-cell malignancies (HTLV-I and HTLV-II) as well as the etiologic agent of the acquired immune deficiency syndrome (HTLV-III). Visna virus, a slowly replicating and pathogenic but nononcogenic retrovirus of sheep, is a member of the subfamily Lentivirinae. Results obtained by molecular hybridization and heteroduplex analysis indicated that a greater extent of nucleotide sequence homology exists between HTLV-III and visna virus than between HTLV-III and any of the other viruses. The homology observed under conditions of low stringency spanned the entire genome, but was strongest in the gag/pol region. The morphogenesis and fine structure of HTLV-III and visna virus also demonstrated striking similarities. The data provide strong evidence for a close taxonomic and thus evolutionary relation between HTLV-III and the Lentivirinae subfamily. 相似文献