[T-Lymphocyte regulation of contact sensitivity: effect of thymectomy in adult mice]

6 weeks after adult thymectomy (ATx) in the Mouse, the contact sensitivity reaction to dinitrofluorobenzene (DNFB) is enhanced. 4 to 7 months after ATx, this reaction is deeply, but incompletely depressed, whereas the concomitant antibody response is not affected. These results suggest that both a suppressor, and an amplifier, T lymphocytes, the life span of which is different after ATx, are involved in the regulation of contact sensitivity. The effect of circulating thymic factor on this reaction suggests that this factor acts exclusively, at least in short treatments, on the suppressor function.