Accelerated Breakdown of Immunological Tolerance Following Whole Body Irradiation

Abstract
Rats were made unresponsive to mouse erythrocytes or bovine serum albumin by a series of injections starting at birth. The unresponsiveness, though not always complete, remained constant in a given animal if antigen injections were continued. In animals irradiated with 550 or 600 r the tolerance usually broke down, with the formation of substantial amounts of antibody. Normal animals also irradiated at a similar age and given repeated injections of mouse erythrocytes formed excess antibody during the 5th to the 13th postirradiation week. By contrast, irradiated rats receiving a single injection of bovine serum albumin in Freund's adjuvant formed less antibody than did nonirradiated controls. The theoretical implications of the work are discussed.