Mitogen-induced lymphocyte proliferation and systemic immune activation in cancer patients.

Proliferative response of lymphocytes to mitogens is known to be decreased in cancer patients. Depressed proliferation of lymphocytes in other disorders has been linked to systemic inflammatory response.Lymphocyte proliferation in response to phytohemagglutinin (PHA) and concanavalin A, as well as urinary neopterin, plasma interferon-gamma and interleukin-4, were investigated in 41 patients with solid tumors.The proliferative response to PHA was significantly depressed in cancer patients at most of the concentrations examined. Urinary neopterin and plasma interferon-gamma were significantly elevated in cancer patients, whereas interleukin-4 was undetectable in all the subjects. A negative correlation was observed between urine neopterin and lymphocyte proliferative response to mitogens.Lymphocyte proliferative response to PHA is significantly diminished in cancer patients, and this depression appears to be partly linked to systemic inflammatory response. Plasma interferon-gamma was significantly increased in cancer patients, whereas interleukin-4 was undetectable.