title: Study of the cells proliferating in parent versus F hybrid mixed lymphocyte culture.
abstract: Caryotypic analysis of the cells dividing in mouse parent-hybrid MLC showed an F1 hybrid cell proliferation, which varied depending upon the source of lymphoid cells used: strong in spleen MLC (sometimes equal to that of the parental cells), less marked in lymph node cell MLC, and most often absent in MLC between cortisone-resistant (CR) thymocytes. MLC between parental spleen cells and F1 CR thymocytes showed, however, that in certain conditions of culture F thymocytes can also proliferate. Using parental or F1 spleen cells lacking T lymphocytes, it was found that F1 cell proliferation is entirely dependent upon the presence of parental T cells, but does not require the presence of T lymphocytes among the F1 cells. Immunofluorescence analysis of the blasts observed in one-way MLC showed that about 70% of the parental blasts were T blasts, and 25%B blasts (containing a high proportion of plasmablasts); among the F1 blasts, there was also the same percentage of B blasts and plasmablasts, but many of the T blasts bore only small amounts of T-cell antigen (MTLA), and there was also about 20%of unstained blasts, possibly T blasts bearing MTLA in amounts undetectable by immunofluorescence. The possibility is discussed that the F1 responding T cells belong to a subpopulation performing a suppressive function; MLC lacking F1 T cells showed increased [3H] thymidine incorporation. The proliferation and differentiation of parental and F1 B cells may result mainly from an unspecific, "polyclonal" triggering.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D005455:Fluorescent Antibody Technique; D006650:Histocompatibility Testing; D006824:Hybridization, Genetic; D008198:Lymph Nodes; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains; D008938:Mitosis; D011830:Radiation Effects; D013154:Spleen; D013601:T-Lymphocytes / Q000276:immunology; D013936:Thymidine / Q000378:metabolism; D013950:Thymus Gland; D013997:Time Factors; D014316:Tritium
chemical_list: D014316:Tritium; D004247:DNA; D013936:Thymidine