title: Increased endogenous retroviral gene expression is a consequence of lymphocyte activation.
abstract: Plasma cells of line 151(5) chickens have been shown to express elevated levels of endogenous retroviral envelope glycoprotein (VEG), measured relative to levels expressed by both immature B cells and resting peripheral B lymphocytes. In this study we analyzed the relationship between peripheral blood lymphocyte (PBL) maturation and the level of VEG expression. A culture system was developed that would support maturation of pokeweed mitogen-activated peripheral B lymphocytes. As analyzed by cytofluorometry, both Ig+ and Ig- lymphoblasts present in the pokeweed mitogen-stimulated cultures expressed detectable levels of VEG in contrast to bursacytes and PBL. Similarly, Ig- blasts, which were present in concanavalin A-stimulated cultures of PBL and presumed to represent activated T cells, were also positive for the expression of VEG. Immature T cells, i.e., thymocytes, although negative by immunofluorescence analysis, expressed VEG at levels that were detectable by radioimmunochemical techniques. These results indicate that T cells as well as B cells constitutively express VEG, and that mitogenic activation of the resting lymphocyte induces an increase in VEG expression.
mesh_terms: D000818:Animals; D001353:Avian Leukosis / Q000276:immunology; D001402:B-Lymphocytes / Q000032:analysis / Q000276:immunology; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D002645:Chickens; D005434:Flow Cytometry; D008213:Lymphocyte Activation; D011043:Pokeweed Mitogens / Q000494:pharmacology; D012190:Retroviridae / Q000235:genetics* / Q000276:immunology; D013601:T-Lymphocytes / Q000032:analysis / Q000276:immunology; D014759:Viral Envelope Proteins / Q000235:genetics*
chemical_list: D011043:Pokeweed Mitogens; D014759:Viral Envelope Proteins