title: Concanavalin A-mediated polyclonal helper assay of normal thymocytes and its use for the analysis of ontogeny.
abstract: A concanavalin A (Con A)-mediated polyclonal helper assay system was established by using the thymus cells or splenic T cells as a source of helper T cells. When splenic B cells were cocultured with thymus cells or splenic Lyt-2- T cells in the presence of an optimal dose of Con A, B Cells were polyclonally activated and differentiated into immunoglobulin-secreting cells. This Con A-mediated helper activity was completely inhibited by the addition of alpha-methyl-D-mannoside and could not be substituted by culture supernatant of Con A-stimulated thymocytes or splenic T cells. Almost all the activity of the thymus cells was carried by peanut agglutinin low binding population. Genetic restriction between T and B cells was not observed in this helper function. In ontogeny, Con A-mediated helper activity in the thymus was first detected at a few days after birth and reached the adult level at about 1 week of age. The polyclonal helper assay system developed in the present study provides a sensitive system to analyse the helper function of thymus cells and also to delineate the early phase of the differentiation of helper T cell population.
mesh_terms: D000367:Age Factors; D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology*; D007075:Immunoglobulin M / Q000096:biosynthesis; D008211:Lymphocyte Cooperation / Q000528:radiation effects; D008285:Major Histocompatibility Complex; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011952:Receptors, Concanavalin A / Q000502:physiology; D011975:Receptors, Mitogen / Q000032:analysis; D013154:Spleen / Q000166:cytology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000254:growth & development / Q000276:immunology*; D013997:Time Factors
chemical_list: D007075:Immunoglobulin M; D011952:Receptors, Concanavalin A; D011975:Receptors, Mitogen; C038223:peanut agglutinin receptor; D003208:Concanavalin A