Response of cows with lymphoma to the intradermal injection of tumor cell antigens and phytohemagglutinin.

Tumor cell-membrane antigens did not elicit specific intradermal reactions in cows with lymphoma and were therefore not effective in identifying animals with tumor. Sixty-two percent (8/13) of cows with lymphoma in the advanced stages of disease responded poorly to the intradermal injection of a nonspecific mitogen (PHA-M) and normal lymphoid cell extracts. This finding may explain the lack of response to the tumor cell extracts that some cows with lymphoma and indicates the presence of immune deficits in animals with lymphoma. Six of eight animals with tumor and poor cutaneous sensitivity had sera that inhibited the blastogenesis of normal lymphocytes. The presence of this inhibitory material is associated with the presence of tumor, not with bovine leukemia virus infection and partially accounts for the relative cutaneous anergy in cattle with lymphoma.