EFFECTS OF X‐IRRADIATION ON ANTIGEN LOCALIZATION IN LYMPHOID FOLLICLES

Publisher Website
Google Scholar
Abstract
Summary: The effects of whole body X‐irradiation before or after the injection of 125I‐labelled Salmonella flagellar antigens on (a) antibody production and (b) antigen distribytion through the lymphoid system were investigated.Whole body X‐irradiation (450 R) caused marked depression of both γM and γG responses if given one day before antigen. With a high dose of the strongest antigen, but not with a low dose or with the weaker antigen, two further observations were made: (a) colchicine could restore antibody‐forming capacity, and (b) X‐ray given after antigen actually caused an enhanced immune response.X‐irradiation caused subtle but important changes in antigen localization. The anatomical structure, presumably cytoplasmic fibrils, in the lymphoid follicles responsible for antigen trapping was remarkably radioresistant. Little damage could be observed with doses less than 1250 R, and it took 8000 R to destroy the structure completely. However, the follicular mechanism was not functionally intact. Spleen antoradiographs and whole organ counts showed a lowered capacity of the web to retain antigen. Lymph node autoradiographs showed abnormal persistence of labelling in a subsinus rim of cortical phagocytes. This was interpreted to indicate an X‐ray induced Interference with antigen migration.X‐irradiation had no observable effect on the sinus macrophages of the lymph node medulla. This once again suggests that their function is less specialized than that of the follicular antigen‐retaining cells.
Funding Information
  • U.S. Public Health Service