Additional Examples of Acquired Immunity in Thymectomized Animals

Abstract

The effect of neonatal thymectomy in mice on the development of immediate and delayed skin reactions was studied by Russe and Crowle (1965). CF₁ mice were either thymectomized within 24 hours after birth or treated with daily intraperitoneal injections of rabbit antimouse thymic lymphocyte serum for a period of 24 to 84 days; at the age of 4 to 6 weeks, these animals were given two weekly sensitizing injections of ovalbumin or BSA in complete Freund’s adjuvant. Thymectomized and serum-treated animals only developed severely impaired immediate and delayed hypersensitivity to these antigens as compared to nonoperated controls. This impairment, however, was temporary in both groups since upon reinjection of the sensitizing antigen or when sensitization was started at the age of 6 months, no difference was found between skin reactions of thymectomized, serumtreated, or nontreated mice.