Serum proteins in prostatic cancer. II. Effect on in vitro cell-mediated immunologic responsiveness

The sera from patients with prostatic cancer have been observed to posses an unidentified factor capable of inhibiting the migration of leukocytes and the proliferative response to the nonspecific mitogen, phytohemagglutinin. Observation of inhibition of these two suggested in vitro correlates fo cell-mediated immunologic responsiveness emphasizes (1) the importance to the adjunctive diagnosis and prognosis of patients with malignancy of identifying the presence of abnormal serum proteins, and (2) the role of humoral inhibitory or "immunoregulatory" factors as potential abrogators of mechanisms of host resistance, for example, immunologic surveillance, and thus the degree to whcih the host may respond to his tumor.