INDOMETHACIN ENHANCEMENT OF IMMUNOCOMPETENCE IN MELANOMA PATIENTS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 90  (1) , 77-84
Abstract
Lymphocyte responses to the mitogens concanavalin (Con) A and phytohemagglutinin (PHA) are important in vitro parameters of immunocompetence in cancer patients. The tempo and intensity of this response is regulated by monocytes. The blood lymphocyte response to 1 or both of these mitogens was significantly depressed in 32 of 33 melanoma patients compared to 29 normal control subjects. These responses were significantly enhanced when the drug indomethacin, a prostaglandin synthetase inhibitor, was added to cultures of peripheral blood mononuclear cells (PBMC) from the melanoma patients but not from the normal control subjects. At a 1 .mu.g/ml dose of Con A the mean response of melanoma patients increased from 56 to 81% of the normal mean response; at 20 .mu.g/ml PHA the mitogen response increased from 57 to 77% of normal when PMBC were incubated with indomethacin (P < 0.001). Indomethacin enhanced the mitogen responses of melanoma patients by 35-85%; it increased the response in normal subjects by only 5-15%. The mitogen response of monocyte-depleted ER+ [erythrocyte rosette positive] lymphocytes for melanoma patients was equivalent to that of normal control subjects with no enhancement in the presence of indomethacin. The enhancement by indomethacin in melanoma patients was not significantly influenced by their stage of disease, age or the proportion of blood monocytes. The decreased levels of cellular immunocompetence in these melanoma patients as measured by their lymphocyte proliferative responses to mitogens appears to be associated with an abnormality in monocyte function that is partially corrected by indomethacin.