title: Lectin effects on thymic suppression of hemagglutinin production in vitro by spleen fragments from Xenopus laevis, the South African clawed toad.
abstract: Suppression of hemagglutinin (HA) production was studied in co-cultures of thymus and spleen fragments from the South African clawed toad, Xenopus laevis. Concanavalin (Con)A and peanut (PNA) and wheatgerm (WGA)agglutinins were tested in conjunction with, or as a substitute for antigenic induction of thymus suppression. While thymuses from animals injected with PNA or WGA and antigen expressed suppressor function, those treated with Con A and antigen did not. Spleen fragments from animals challenged with PNA or WGA and antigen were resistant to suppression by normal thymus in reciprocal co-cultures; those receiving Con A and antigen alone were equally suppressible. All three lectins can substitute for antigen in the induction of thymus suppression. However, only PNA and WGA induce suppressor function in Xenopus spleen. Since WGA can induce splenic suppression in adult thymectomized animals, it is now possible to distinguish thymic and peripheral aspects of suppression of HA in this primitive vertebrate.
mesh_terms: D000818:Animals; D046508:Culture Techniques; D004912:Erythrocytes / Q000276:immunology; D006388:Hemagglutinins / Q000096:biosynthesis; D007108:Immune Tolerance; D037102:Lectins / Q000494:pharmacology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology*; D014982:Xenopus laevis / Q000276:immunology*
chemical_list: D006388:Hemagglutinins; D037102:Lectins