A comparative study of natural cytotoxicity and the leukocyte migration inhibition in human melanoma stages I and II.

White blood cells (lymphocytes or leukocytes) obtained from patients suffering from localized skin melanoma and from persons without malignant diseases were tested in the microcytotoxicity assay and leukocyte migration inhibition test using indentical relevant and control targets and antigens. In both test systems the reactivities recorded were found to be independent of target/antigen effector cell combinations, indicating that these interactions were nonspecific. The nonspecific reactivities measured by microcytotoxicity assay (natural cytotoxicity) and the leukocyte migration inhibition test were compared by the simultaneous implementation of the two test systems using white cells from the same blood sample. No correlation between significant leukocyte migration inhibition and significant natural cytotoxicity was found. It is concluded that the leukocyte migration inhibition test as well as the microcytotoxicity assay were neither specific nor mutually supplementary in evaluation of tumor-directed immunity in localized malignant melanoma.