[en] Bovine leukemia virus (BLV) Tax protein, a transcriptional activator of viral expression, is essential for viral replication in vivo. Tax is believed to be involved in leukemogenesis because of its second function, immortalization of primary cells in vitro. These activities of Tax can be dissociated on the basis of point mutations within specific regions of the protein. For example, mutation of the phosphorylation sites at serines 106 and 293 abrogates immortalization potential in vitro but maintains transcriptional activity. This type of mutant is thus particularly useful for unraveling the role of Tax immortalization activity during leukemogenesis independently of viral replication. In this report, we describe the biological properties of BLV recombinant proviruses mutated in the Tax phosphorylation sites (BLVTax106+293). Titration of the proviral loads by semiquantitative PCR revealed that the BLV mutants propagated at wild-type levels in vivo. Furthermore, two animals (sheep 480 and 296) infected with BLVTax106+293 developed leukemia or lymphosarcoma after 16 and 36 months, respectively. These periods of time are within the normal range of latencies preceding the onset of pathogenesis induced by wild-type viruses. The phenotype of the mutant-infected cells was characteristic of a B lymphocyte (immunoglobulin M positive) expressing CD11b and CD5 (except at the final stage for the latter marker), a pattern that is typical of wild-type virus-infected target cells. Interestingly, the transformed B lymphocytes from sheep 480 also coexpressed the CD8 marker, a phenotype rarely observed in tumor biopsies from chronic lymphocytic leukemia patients. Finally, direct sequencing of the tax gene demonstrated that the leukemic cells did not harbor revertant proviruses. We conclude that viruses expressing a Tax mutant unable to transform primary cells in culture are still pathogenic in the sheep animal model. Our data thus provide a clear example of the discordant conclusions that can be drawn from in vitro immortalization assays and in vivo experiments. These observations could be of interest for other systems, such as the related human T-cell leukemia virus type 1, which currently lack animal models allowing the study of the leukemogenic process.
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Bibliography
Adam E., Kerkhofs P., Mammerickx M., Burny A., Kettman R., Willems L. (1996) The CREB, ATF-1, and ATF-2 transcription factors from bovine leukemia virus-infected B lymphocytes activate viral expression. J. Virol. 70:1990-1999.
Adam E., Kerkhofs P., Mammerickx M., Kettmann R., Burny A., Droogmans L., Willems L. (1994) Involvement of the cyclic AMP-responsive element binding protein in bovine leukemia virus expression in vivo. J. Virol. 68:5845-5853.
Akagi T., Ono H., Nyunoya H., Shimotohno K. (1997) Characterization of peripheral blood T-lymphocytes transduced with HTLV-I Tax mutants with different trans-activating phenotypes. Oncogene 14:2071-2078.
Akashi K., Shibuya T., Nakamura M., Oogami A., Harada M., Niho Y. (1998) Large granular lymphocytic leukaemia with a mixed T-cell/B-cell phenotype. Br. J. Haematol. 100:291-294.
Birkebak T.A., Palmer G.H., Davis W.C., Knowles D.P., McElwain T.F. (1994) Association of GP51 expression and persistent CD5+ B-lymphocyte expansion with lymphomagenesis in bovine leukemia virus infected sheep. Leukemia 8:1890-1899.
Blattner W.A. (1999) Human retroviruses: Their role in cancer. Proc. Assoc. Am. Physicians 111:563-572.
Boris-Lawrie K., Altanerova V., Altaner C., Kucerova L., Temin H.M. (1997) In vivo study of genetically simplified bovine leukemia virus derivatives that lack tax and rex. J. Virol. 71:1514-1520.
Boros I.M., Tie F., Giam C.Z. (1995) Interaction of bovine leukemia virus transactivator Tax with bZip proteins. Virology 214:207-214.
Casoli C., Cimarelli A., Bertazzoni U. (1995) Cellular tropism of human T-cell leukemia virus type II is enlarged to B lymphocytes in patients with high proviral load. Virology 206:1126-1128.
Chevallier N., Berthelemy M., Le Rhun D., Laine V., Levy D., Schwartz-Cornil I. (1998) Bovine leukemia virus-induced lymphocytosis and increased cell survival mainly involve the CD11b+ B-lymphocyte subset in sheep. J. Virol. 72:4413-4420.
Ciminale V., Hatziyanni M., Felber B.K., Bear J., Hatzakis A., Pavlakis G.N. (2000) Unusual CD4+CD8+ phenotype in a Greek patient diagnosed with adult T-cell leukemia positive for human T-cell leukemia virus type I (HTLV-I). Leukocyte Res. 24:353-358.
Coekerell G.L., Rovnak J., Green P.L., Chen I.S. (1996) A deletion in the proximal untranslated pX region of human T-cell leukemia virus type II decreases viral replication but not infectivity in vivo. Blood 87:1030-1035.
Coscoy L., Gonzalez-Dunia D., Tangy F., Syan S., Brahic M., Ozden S. (1998) Molecular mechanism of tumorigenesis in mice transgenic for the human T cell leukemia virus Tax gene. Virology 248:332-341.
Dequiedt F., Hanon E., Kerkhofs P., Pastoret P.P., Portetelle D., Burny A., Kettmann R., Willems L. (1997) Both wild-type and strongly attenuated bovine leukemia viruses protect peripheral blood mononuclear cells from apoptosis. J. Virol. 71:630-639.
Derse D. (1987) Bovine leukemia virus transcription is controlled by a virus-encoded trans-acting factor and by cis-acting response elements. J. Virol. 61:2462-2471.
Derse D., Mikovits J., Ruscetti F. (1997) X-I and X-II open reading frames of HTLV-I are not required for virus replication or for immortalization of primary T-cells in vitro. Virology 237:123-128.
Fang J., Kushida S., Feng R., Tanaka M., Kawamura T., Abe H., Maeda N., Onobori M., Hori M., Uchida K. (1998) Transmission of human T-cell leukemia virus type 1 to mice. J Virol 72:3952-3957.
Franchini G., Streicher H. (1995) Human T-cell leukaemia virus. Bailliere's. Clin. Haematol. 8:131-148.
Fujita M. (1995) Differences in sensitivity to induction of apoptosis among rat fibroblast cells transformed by HTLV-I tax gene or cellular nuclear oncogenes. Oncogene 11:15-20.
Furukawa S., Sasai K., Matsubara J., Yabuta K., Hiramatsu K., Yamamoto J., Shirai T., Okumura K. (1992) Increase in T cells expressing the gamma/delta receptor and CD4+CD8+ double-positive T cells in primary immunodeficiency complicated by human T-cell lymphotropic virus type I infection. Blood 80:3253-3255.
Gongora-Biachi R.A., Gonzalez-Martinez P., Castros-Sansores C., Pavia-Ruz N., Rudolph D.L., Lal R.B. (1993) Human T lymphotropic virus type II (HTLV-II) infection among female prostitutes in Yucatan, Mexico. Am. J. Med. Sci. 306:207-211.
Grassmann R., Berchtold S., Radant I., Alt M., Fleckenstein B., Sodroski J.G., Haseltine W.A., Ramstedt U. (1992) Role of human T-cell leukemia virus type I X region proteins in immortalization of primary human lymphocytes in culture. J. Virol. 66:4570-4575.
Grassmann R., Dengler C., Muller-Fleckenstein I., Fleckenstein B., McGuire K., Dokhelar M.C., Sodroski J.G., Haseltine W.A. (1989) Transformation to continuous growth of primary human T lymphocytes by human T-cell leukemia virus type I X-region genes transduced by a herpesvirus saimiri vector. Proc. Natl. Acad. Sci. USA 86:3351-3355.
Grossman W.J., Kimata J.T., Wong F.H., Zutter M., Ley T.J., Ratner L. (1995) Development of leukemia in mice transgenic for the tax gene of human T-cell leukemia virus type I. Proc. Natl. Acad. Sci. USA 92:1057-1061.
Habu K., Nakayama-Yamada J., Asano M., Saijo S., Itagaki K., Horai R., Yamamoto H., Sekiguchi T., Nosaka T., Hatanaka M., Iwakura Y. (1999) The human T cell leukemia virus type I-tax gene is responsible for the development of both inflammatory polyarthropathy resembling rheumatoid arthritis and noninflammatory ankylotic arthropathy in transgenic mice. J. Immunol. 162:2956-2963.
Hall A.P., Irvine J., Blyth K., Cameron E.R., Onions D.E., Campbell M.E. (1998) Tumours derived from HTLV-I tax transgenic mice are characterized by enhanced levels of apoptosis and oncogene expression. J. Pathol. 186:209-214.
Hinrichs S.H., Nerenberg M., Reynolds R.K., Khoury G., Jay G. (1987) A transgenic mouse model for human neurofibromatosis. Science 237:1340-1343.
Hollsberg P. (1999) Mechanisms of T-cell activation by human T-cell lymphotropic virus type I. Microbiol. Mol. Biol. Rev. 63:308-333.
Kazanji M., Moreau J.P., Mahieux R., Bonnemains B., Bomford R., Gessain A., De The G. (1997) HTLV-I infection in squirrel monkeys (Saimiri sciureus) using autologous, homologous, or heterologous HTLV-I-transformed cell lines. Virology 231:258-266.
Kettmann R., Burny A., Callebaut I., Droogmans L., Mammerickx M., Willems L., Portetelle D. (1994) Bovine leukemia virus., J. A. Levy (ed.), The Retroviridae,Plenum Press, New York, N.Y; 3:39-81.
Kimata J.T., Wong F.H., Wang J.J., Ratner L. (1994) Construction and characterization of infectious human T-cell leukemia virus type 1 molecular clones. Virology 204:656-664.
Koelliker D.D., Steele P.E., Hurtubise P.E., Flessa H.C., Sheng Y.P., Swerdlow S.H. (1994) CD8-positive B-cell chronic lymphocytic leukemia: A report of two cases. Am. J. Clin. Pathol. 102:212-216.
Kucerova L., Altanerova V., Altaner C., Boris-Lawrie K. (1999) Bovine leukemia virus structural gene vectors are immunogenic and lack pathogenicity in a rabbit model. J. Virol. 73:8160-8166.
Lagarias D.M., Radke K. (1989) Transcriptional activation of bovine leukemia virus in blood cells from experimentally infected, asymptomatic sheep with latent infections. J. Virol. 63:2099-2107.
Lal R.B., Owen S.M., Rudolph D.L., Dawson C., Prince H. (1995) In vivo cellular tropism of human T-lymphotropic virus type II is not restricted to CDS+ cells. Virology 210:441-447.
Land H. (1995) Transformation of primary rat embryo cells. Methods Enzymol 254:37-41.
Land H., Parada L.F., Weinberg R.A. (1983) Tumorigenic conversion of primary embryo fibroblasts requires at least two cooperating oncogenes. Nature 304:596-602.
Lydy S.L., Conner M.E., Marriott S.J. (1998) Relationship between anti-Tax antibody responses and cocultivatable virus in HTLV-I-infected rabbits. Virology 250:60-66.
Macchi B., Graziani G., Zhang J., Mastino A. (1993) Emergence of double-positive CD4/CD8 cells from adult peripheral blood mononuclear cells infected with human T cell leukemia virus type I (HTLV-I). Cell Immunol. 149:376-389.
Martin M.P., Biggar R.J., Hamlin-Green G., Staal S., Mann D. (1993) Large granular lymphocytosis in a patient infected with HTLV-II. AIDS Res. Hum. Retroviruses 9:715-719.
Matheise J.P., Delcommenne M., Mager A., Didembourg C.H., Letesson J.J. (1992) CD5+ B cells from bovine leukemia virus infected cows are activated cycling cells responsive to interleukin 2. Leukemia 6:304-309.
Matsumoto K., Shibata H., Fujisawa J.I., Inoue H., Hakura A., Tsukahara T., Fujii M. (1997) Human T-cell leukemia virus type 1 Tax protein transforms rat fibroblasts via two distinct pathways. J. Virol. 71:4445-4451.
Melrom R., Moss S., Brenner J. (1997) Bovine leukemia virus-gp51 antigen expression is associated with CD5 and IgM markers on infected lymphocytes. Vet. Immunol. Immunopathol. 59:113-119.
Mirsky M.L., Olmstead C.A., Da Y., Lewin H.A. (1996) The prevalence of proviral bovine leukemia virus in peripheral blood mononuclear cells at two subclinical stages of infection. J. Virol. 70:2178-2183.
Murakami K., Aida Y., Kageyama R., Numakunai S., Ohshima K., Okada K., Ikawa Y. (1994) Immunopathologic study and characterization of the phenotype of transformed cells in sheep with bovine leukemia virus-induced lymphosarcoma. Am. J. Vet. Res. 55:72-80.
Murakami K., Okada K., Ikawa Y., Aida Y. (1994) Bovine leukemia virus induces CD5-B cell lymphoma in sheep despite temporarily increasing CD5+ B cells in asymptomatic stage. Virology 202:458-465.
Murata K., Fujita M., Honda T., Yamada Y., Tomonaga M., Shiku H. (1996) Rat primary T cells expressing HTLV-tax gene transduced by a retroviral vector: In vitro and in vivo characterization. Int. J. Cancer 68:102-108.
Nerenberg M., Hinrichs S.H., Reynolds R.K., Khoury G., Jay G. (1987) The tat gene of human T-lymphotropic virus type 1 induces mesenchymal tumors in transgenic mice. Science 237:1324-1329.
Newbound G.C., Andrews J.M., O'Rourke J.P., Brady J.N., Lairmore M.D. (1996) Human T-cell lymphotropic virus type 1 Tax mediates enhanced transcription in CD4+ T lymphocytes. J. Virol. 70:2101-2106.
Ohata J., Matsuoka M., Yamashita T., Tojo A., Tani K., Asano S. (1999) CD4/CD8 double-positive adult T cell leukemia with preceding cytomegaloviral gastroenterocolitis. Int. J. Hematol. 69:92-95.
Ohya O., Tomaru U., Yamashita I., Kasai T., Morita K., Ikeda H., Wakisaka A., Yoshiki T. (1997) HTLV-I induced myeloneuropathy in WKAH rats: Apoptosis and local activation of the HTLV-pX and TNF-alpha genes implicated in the pathogenesis. Leukemia 11(SUPPL. 3):255-257.
Powers M.A., Radke K. (1992) Activation of bovine leukemia virus transcription in lymphocytes from infected sheep: Rapid transition through early to late gene expression. J. Virol. 66:4769-4777.
Pozzatti R., Vogel J., Jay G. (1990) The human T-lymphotropic virus type I tax gene can cooperate with the ras oncogene to induce neoplastic transformation of cells. Mol. Cell. Biol. 10:413-417.
Ressler S., Connor L.M., Marriott J. (1996) Cellular transformation by human T-cell leukemia virus type I. FEMS Microbiol. Lett. 140:99-109.
Robek M.D., Ratner L. (1999) Immortalization of CD4(+) and CD8(+) T lymphocytes by human T-cell leukemia virus type 1 Tax mutants expressed in a functional molecular clone. J. Virol. 73:4856-4865.
Rosin O., Koch C., Schmitt I., Semmes O.J., Jeang K.T., Grassmann R. (1998) A human T-cell leukemia virus Tax variant incapable of activating NF-kappaB retains its immortalizing potential for primary T-lymphocytes. J Biol. Chem. 273:6698-6703.
Ross T.M., Narayan M., Fang Z.Y., Minella A.C., Green P.L. (2000) Human T-cell leukemia virus type 2 tax mutants that selectively abrogate NF-κB or CREB/ATF activation fail to transform primary human T cells. J. Virol. 74:2655-2662.
Ross T.M., Pettiford S.M., Green P.L. (1996) The tax gene of human T-cell leukemia virus type 2 is essential for transformation of human T lymphocytes. J. Virol. 70:5194-5202.
Saggioro D., D'Agostino D.M., Chieco-Bianchi L. (1999) Analysis of Tax-expressing cell lines generated from HTLV-I tax-transgenic mice: Correlation between c-myc overexpression and neoplastic potential. Exp. Cell Res. 247:525-533.
Schatzl H., Tschikobava M., Rose D., Voevodin A., Nitschko H., Sieger E., Busch U., Von Der Helm K. (1993) The Sukhumi primate monkey model for viral lymphomogenesis: High incidence of lymphomas with presence of STLV-I and EBV-like virus. Leukemia 7(SUPPL. 2).
Schwartz I., Bensaid A., Polack B., Perrin B., Berthelemy M., Levy D. (1994) In vivo leukocyte tropism of bovine leukemia virus in sheep and cattle. J. Virol. 68:4589-4596.
Seto A., Isono T., Ogawa K. (1991) Infection of inbred rabbits with cell-free HTLV-1. Leukocyte Res. 15:105-110.
Smith M.R., Greene W.C. (1991) Type I human T cell leukemia virus tax protein transforms rat fibroblasts through the cyclic adenosine monophosphate response element binding protein/activating transcription factor pathway. J. Clin. Investig. 88:1038-1042.
Stone D.M., Hof A.J., Davis W.C. (1995) Up-regulation of IL-2 receptor alpha and MHC class II expression on lymphocyte subpopulations from bovine leukemia virus infected lymphocytotic cows. Vet. Immunol. Immunopathol. 48:65-76.
Sun B., Fang J., Yagami K., Kushida S., Tanaka M., Uchida K., Miwa M. (1999) Age-dependent paraparesis in WKA rats: Evaluation of MHC k-haplotype and HTLV-1 infection. J. Neurol Sci. 167:16-21.
Tanaka A., Takahashi C., Yamaoka S., Nosaka T., Maki M., Hatanaka M. (1990) Oncogenic transformation by the tax gene of human T-cell leukemia virus type I in vitro. Proc. Natl. Acad. Sci. USA 87:1071-1075.
Tarsis S.L., Yu M.T., Parks E.S., Persaud D., Munoz J.L., Parks W.L. (1998) Human T-lymphocyte transformation with human T-cell lymphotropic virus type 2. J. Virol. 72:841-846.
Tomaru U., Ikeda H., Ohya O., Abe M., Kasai T., Yamasita I., Morita K., Wakisaka A., Yoshiki T. (1996) Human T lymphocyte virus type I-induced myeloneuropathy in rats: Implication of local activation of the pX and tumor necrosis factor-alpha genes in pathogenesis. J. Infect. Dis. 174:318-323.
Uchiyama T. (1997) Human T cell leukemia virus type I (HTLV-I) and human diseases. Annu. Rev. Immunol. 15:15-37.
Van Den Broeke A., Bagnis C., Ciesiolka M., Cleuter Y., Gelderblom H., Kerkhofs P., Griebel P., Mannoni P., Burny P. (1999) In vivo rescue of a silent Tax-deficient bovine leukemia virus from a tumor-derived ovine B-cell line by recombination with a retrovirally transduced wild-type tax gene. J. Virol. 73:1054-1065.
Willems L., Gegonne A., Chen G., Burny A., Kettmann R., Ghysdael J. (1987) The bovine leukemia virus p34 is a transactivator protein. EMBO J. 6:3385-3389.
Willems L., Grimonpont C., Heremans H., Rebeyrotte N., Chen G., Portetelle D., Burny A., Kettmann R. (1992) Mutations in the bovine leukemia virus Tax protein can abrogate the long terminal repeat-directed transactivating activity without concomitant loss of transforming potential. Proc. Natl. Acad. Sci. USA 89:3957-3961.
Willems L., Grimonpont C., Kerkhofs P., Capiau C., Gheysen D., Conrath K., Roussef R., Mamoun R., Portetelle D., Burny A., Adam E., Lefebvre L., Twizere J.C., Heremans H., Kettmann R. (1998) Phosphorylation of bovine leukemia virus Tax protein is required for in vitro transformation but not for transactivation. Oncogene 16:2165-2176.
Willems L., Heremans H., Chen G., Portetelle D., Billiau A., Burny A., Kettmann R. (1990) Cooperation between bovine leukaemia virus transactivator protein and Ha-ras oncogene product in cellular transformation. EMBO J. 9:1577-1581.
Willems L., Kerkhofs P., Attenelle L., Burny A., Portetelle D., Kettmann R. (1997) The major homology region of bovine leukaemia virus p24gag is required for virus infectivity in vivo. J. Gen. Virol. 78:637-640.
Willems L., Kettmann R., Burny A. (1991) The amino acid (157-197) peptide segment of bovine leukemia virus p34tax encompass a leucine-rich globally neutral activation domain. Oncogene 6:159-163.
Willems L., Kettmann R., Dequiedt F., Portetelle D., Voneche V., Cornil I., Kerkhofs P., Burny A., Mammerickx M. (1993) In vivo infection of sheep by bovine leukemia virus mutants. J. Virol. 67:4078-4085.
Willems L., Burny A., Collete D., Dangoisse O., Gatot J.S., Kerkhofs P., Lefebvre L., Merezak M., Portetelle D., Twizere J.C., Kettmann R. (1999) Bovine leukemia virus as a model for human T-cell leukemia virus. Curr. Top. Virol. 1:139-167.
Yamaoka S., Inoue H., Sakurai M., Sugiyama T., Hazama M., Yamada T., Hatanaka M. (1996) Constitutive activation of NF-kappa B is essential for transformation of rat fibroblasts by the human T-cell leukemia virus type I Tax protein. EMBO J. 15:873-887.
Yamaoka S., Tobe T., Hatanaka M. (1992) Tax protein of human T-cell leukemia virus type I is required for maintenance of the transformed phenotype. Oncogene 7:433-437.
Yoshida M. (1996) Molecular biology of HTLV-I: Recent progress. J. Acquir. Immune Defic. Syndr. Hum. Retrovirol. 13(SUPPL. 1).
Yoshida M. (1997) Howard Temin Memorial Lectureship: Molecular biology of HTLV-1: Deregulation of host cell gene expression and cell cycle. Leukemia 11(SUPPL. 3):1-2.
Zhao T.M., Robinson M.A., Bowers F.S., Kindt T.J. (1996) Infectivity of chimeric human T-cell leukemia virus type I molecular clones assessed by naked DNA inoculation. Proc. Natl. Acad. Sci. USA 93:6653-6658.
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