Host response to challenge with SA7-induced autochthonous tumor cells.

Abstract

AbstractThe fate of SA7‐induced autochthonous tumor transplants in inbred hamsters (strain LSH) was determined. It was found that the host response to tumor autografts was not uniform. Out of a series of 30 such transplants, evidence for host resistance was found in 12 instances. Conversely, in six cases the tumor cell inoculum grew only or more rapidly in the autochthonous host. In three tests the challenge tumor growth rate was similar in both autochthonous and control (s), and in nine trials neoplasms did not develop in either recipient. In the last category the failure of the tumor cells to grow was most likely due to host resistance rather than to poor transplantability because it was found that SA7 tumor lines which were poorly oncogenic or non‐oncogenic in adult animals invariably produced lethal tumors in infant hamsters. It was concluded that a) hamsters can manifest autochthonous tumor immunity to SA7‐induced neoplasms and b) one factor which contributed to the diversity of the host response was the size of the primary tumor prior to and shortly after grafting.