Macrophage-Bound Antigens

[摘要] Macrophage-antigen is quite effective in activating T cells which are involved in mediating delayed hypersensitivity (DH) and in helping B cells produce antibodies. In this study we determined if this property was unique to macrophages by immunizing guinea pigs with antigen bound to macrophages, lymphocytes, thymocytes or hepatoma cells. Cells from unimmunized guinea pigs were incubated in vitro for 60 to 90 min with 125I tetanus toxoid or guinea pig albumin conjugated with orthanilic acid (GPA.OA), washed, and then injected into syngeneic unimmunized guinea pigs.Macrophages took up 10 to 18 times more antigen than the other cells. To compensate for this difference in uptake, we injected equal doses of antigen rather than cells. Even with injection of fewer macrophages, macrophage-antigen was more effective than lymphocyte-antigen and soluble antigen in inducing DH and in priming for production of antibodies. Thymocyte-antigen and hepatoma antigen were ineffective in inducing immunity. Only macrophage-antigen was capable of activating T cells when guinea pigs were immunized by the intracardiac route or when weakly immunogenic GPA.OA was used.These observations, with those of the previous paper, suggest that an initial interaction of antigen with macrophages but not with immunocompetent lymphocytes, immature thymocytes or hepatoma cells leads to activation of T cells involved in mediating DH and in helping B cells to form antibodies.

[学科分类] 生物科学（综合）