Retroviral transformation in vitro of chicken T cells expressing either alpha/beta or gamma/delta T cell receptors by reticuloendotheliosis virus strain T.

Abstract

Exposure of normal juvenile chicken bone marrow cells to the replication defective avian reticuloendotheliosis virus strain T (REV-T) (chicken syncytial virus [CSV]) in vitro resulted in the generation of transformed cell lines containing T cells. The transformed T cells derived from bone marrow included cells expressing either alpha/beta or gamma/delta T cell receptors (TCRs) in proportions roughly equivalent to the proportions of TCR-alpha/beta and TCR-gamma/delta T cells found in the normal bone marrow in vivo. Essentially all TCR-alpha/beta-expressing transformed bone marrow-derived T cells expressed CD8, whereas few, if any, expressed CD4. In contrast, among TCR-gamma/delta T cells, both CD8+ and CD8- cells were derived, all of which were CD4-. Exposure of ex vivo spleen cells to REV-T(CSV) yielded transformed polyclonal cell lines containing > 99% B cells. However, REV-T(CSV) infection of mitogen-activated spleen cells in vitro resulted in transformed populations containing predominantly T cells. This may be explained at least in part by in vitro activation resulting in dramatically increased levels of T cell REV-T(CSV) receptor expression. In contrast to REV-T(CSV)-transformed lines derived from normal bone marrow, transformed lines derived from activated spleen cells contained substantial numbers of CD4+ cells, all of which expressed TCR-alpha/beta. While transformed T cells derived from bone marrow were stable for extended periods of in vitro culture and were cloned from single cells, transformed T cells from activated spleen were not stable and could not be cloned. We have therefore dissociated the initial transformation of T cells with REV-T(CSV) from the requirements for long-term growth. These results provide the first demonstration of efficient in vitro transformation of chicken T lineage cells by REV-T(CSV). Since productive infection with REV-T(CSV) is not sufficient to promote long-term growth of transformed cells, these results further suggest that immortalization depends not only upon expression of the v-rel oncogene but also on intracellular factor(s) whose expression varies according to the state of T cell physiology and/or activation.

Multiple mutations contribute to the oncogenicity of the retroviral oncoprotein v-Rel

“…Moreover, vRel-transformed cell lines, established by in vitro infection of chicken spleen cells and which do not shed helper virus, can induce fatal tumors with as few as 100 cells when injected into histocompatible chickens (Lewis et al, 1981). Cells transformed in vitro by v-Rel have been reported to have characteristics of immature pre-B/pre-T cells (Beug et al, 1981;Chen et al, 1988;Morrison et al, 1991;Zhang et al, 1989), abnormal B cells (Chen et al, 1988), immature and mature B cells (Benatar et al, 1991(Benatar et al, , 1992Boehmelt et al, 1995;Keller et al, 1979;Lewis et al, 1981;Sasaki and Koyama, 1989;Shibuya et al, 1982;Zhang et al, 1991), T cells (Barth et al, 1990;Marmor et al, 1993;Schat et al, 1992), myeloid cells (Barth et al, 1990;Morrison et al, 1991), erythroid cells (Morrison et al, 1991), and pre-dendritic cells (Boehmelt et al, 1995).…”

“…Therefore, the transforming and immortalizing activities of v-Rel may both depend on, for example, the ability of v-Rel to increase gene expression, but the sets of genes that cause each e ect may be distinct or partially overlapping. In addition, it appears that there are cellular factors that a ect the ability of v-Rel to immortalize avian lymphoid cells (Marmor et al, 1993).…”

Administration ofSalmonella enteritidis‐immune lymphokine to day‐old turkeys by subcutaneous, oral, and nasal routes: A comparison of effects onSalmonella enteritidisliver invasion, peripheral blood heterophilia and heterophil activation

“…The procedure used to transform the chicken splenic T cells for these experiments was adapted from Marmor et al (1993). Avian reticuloendotheliosis virus was purchased from the American Type Culture Collection (ATCC) (VR-770, Rockville, MD 20852).…”

The drug monosodium luminol (GVT®) preserves thymic epithelial cell cytoarchitecture and allows thymocyte survival in mice infected with the T cell-tropic, cytopathic retrovirus ts1

“…HAART therapies, like those currently in use for treatment of HIV-AIDS, may not restore thymopoiesis even assuming that normal Tprogenitor cells are produced and sent to the thymus from the bone marrow in these patients [66]. This means that naïve T cell exhaustion, thought to be one cause of HIV-1 immunosuppression [9][10][11] might still occur under HAART treatment. For the same reasons, bone marrow or hematopoietic stem cell transplantation, once considered as potential treatments for T cell exhaustion in HIV-AIDS [66][67][68], may not repopulate the thymus either, unless there is a functioning and non-toxic (e.g., low-ROS) microenvironment there in which the stem cells can differentiate to become T cells.…”

“…Interestingly, although HIV-1 and the lentivirus simian immunodeficiency virus (SIV) use CD4 as their surface receptor on T cells, other T cell-tropic retroviruses do not [5][6][7]. Despite this, thymic atrophy, selective infection and killing of CD4+ T-lineage cells, or neoplastic transformation of thymocytes, are common characteristics of diseases caused by these viral agents [8][9][10][11][12][13][14]. At present, the cause of T cell death after infection by these viruses is unknown.…”