Further Studies on the Relation Between Germinal Centers and Cell-Mediated Injury

Abstract

In the first conference on germinal centers in immune response, we presented evidence suggesting that germinal centers and plasma cell proliferation in the medulla were associated with the humoral antibody response, whereas proliferation of lymphocytes in the para-cortical areas of the lymph node, the area containing the mobile pool of small lymphocytes, was associated with specific cell-mediated immunity or delayed hypersensitivity [1]. It was also suggested that these two systems in the lymph node were distinct, both functionally and anatomically. Further studies over the past two years have confirmed this work and continued to emphasize the biologically distinct nature of these two systems in lymphoid tissue. These include the effect of antilymphocyte serum, which has a preferential effect in suppressing cell-mediated immunity rather than humoral antibody production, and deep X-irradiation in a dose that suppresses antibody production without affecting the ability of the animal to show delayed hypersensitivity. Finally, functional differences between these areas of tissue have been found in guinea pig, rat, mouse, and man by a histochemical study of the distribution of activity of the enzymes 5-nucleotidase, alkaline phosphatase, and ATPase in stimulated lymph nodes.