title: Macrophage requirement for the in vitro response to an insolubilized T-independent antigen.
abstract: The role of macrophages in the in vitro response of mouse spleen cells to the insolubilized, T-independent antigen trinitrophenylated polyacrylamide (TNP-PAA) is demonstrated by the following points. The response is abolished by filtration on Sephadex G-10 and can be restored by the addition of splenic adherent cells, deficient in either B or T cells, or by 2-mercaptoethanol (2ME). It is suppressed upon elimination of phagocytic cells by silica, and restored by 2-ME. 2-ME can restore a normal response from zero, in cultures depleted of both adherent and phagocytic cells, and is efficient in the absence of mature T cells. Experiments in microcultures show that large numbers of macrophages can stimulate a supra-optimal response from B cells. This response is only obtained in the presence of the antigen, and is specific for TNP. These results show that microphages, probably by their polyclonal B-cell activator (PBA) property, play a role in the specific response to TNP-PAA. This prompts us to discuss the respective roles in the B-cell response of this PBA activity and of the interaction of the antigen with the specific B-cell receptors.
mesh_terms: D000818:Animals; D000941:Antigens; D001402:B-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D007104:Immune Adherence Reaction; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000276:immunology*; D008297:Male; D008623:Mercaptoethanol / Q000494:pharmacology; D051379:Mice; D008811:Mice, Inbred DBA; D010587:Phagocytosis / Q000187:drug effects; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D014301:Trinitrobenzenes / Q000494:pharmacology
chemical_list: D000941:Antigens; D014301:Trinitrobenzenes; D008623:Mercaptoethanol