Interactions of Sensitized Lymphoid Cells and Homologous Target Cells in Tissue Culture and in Grafts: an Electron Microscopic and Immunofluorescence Study

摘要

The interactions in tissue culture and in graft of sensitized BALB/c spleen cells and homologous L929 fibroblasts have been studied by light microscopy, electron microscopy and immunofluorescence. The system is slightly modified from that introduced by Rosenau and Moon (2–3).Spleen cells become adherent to L cells. While erythrocytes, granulocytes, lymphocytes and monocytes and other cell types in the spleen cell suspension adhere to the L cells, the population of initially adherent cells is effectively restricted to plasma cells and lymphocytes (11). Lymphocytes are predominantly the adherent cells at the outset, but plasma cells increase to about 50% of adherent cells in 24 to 48 hr. The peak in plasma cell number coincides with the period of rapid lysis of L cells. Lymphocytes containing polyribosomes, numerous mitochondra, and segments of granular endoplasmic reticulum are frequently observed. Cells containing globulin are revealed by immunofluorescence. Such cells increase in a manner parallel to that of plasma cells. Most immunofluorescent cells, as viewed under phase contrast, moreover, appear to be plasma cells.I advance the hypothesis that in this system, which is representative of the homograft reaction and perhaps of other instances attributed to delayed hypersensitivity, a class of lymphocytes becomes plasma cells. The plasma cells are secretory cells. They secrete a type or types of antibody or toxin that may itself damage the L cells. But complement may also be produced by adherent plasma cells and, in conjunction with the antibody or toxin, may cause lysis of the homologous cells.