Monitoring of nonspecific cell-mediated immunity in cancer patients. I. Frequent dissociation between the responses of skin tests to recall antigens and in vitro lymphocyte transformation.

No correlation was found between in vivo delayed hypersensitivity responses in cancer patients and in vitro lymphocyte transformation by mitogens or antigens, even when the same antigen [purified protein derivative of tuberculin (PPD)] was used for both the in vivo and in vitro testing. However, there was a good correlation between the in vitro lymphocyte transformation tests with PPD and with the mitogens phytohemagglutinin and pokeweed mitogen.