TRANSPLANTATION OF THYMIC TISSUE IN INBRED STRAINS OF MICE

Abstract

SUMMARY: Thymic tissue has been transplanted between donor and host mice of different ages. It has been found that thymic tissue more than a few days old loses weight rapidly when transplanted to a host, and that beyond this age loss of weight is independent of the age of either donor or host. For the first few days after birth the thymus gland is capable of growth when transplanted to a host and, unlike the host's own thymus, it is unaffected by the increased output of adrenocortical hormones which occurs during pregnancy. The behaviour of a thymic graft seems to be independent of the presence or absence of the host's own thymus gland. The presence of additional thymic tissue in a host appears to have no effect on body growth, weight of adrenal glands, gonads and superficial lymph nodes, or on the weight and histological condition of the thymus of the host.