[Circulating K and NK cells in malignant melanoma using monoclonal antibodies]

K-Cells and NK-Cells are specialized lymphocytes eliciting antibody-dependent cellular cytotoxicity (ADCC) which may play an important part in the immunologic surveillance of various tumors. On the other hand, their cytotoxic impact on neoplastic tissue may be reduced by the tumor itself. By means of monoclonal antibodies (anti-leu 7 = HNK 1), we determined the number of circulating killer cells (K-cells) and natural killer cells (NK-cells) in the peripheral blood of 35 patients with malignant melanoma (MM). Our studies did not reveal any differences in the amount of circulating K-cells or NK-cells between patients with MM at various clinical stages (n = 35) and a control group of healthy persons (n = 29); neither could there be detected any relation towards the age of the patients in both groups. In the advanced clinical stages III and IV of MM (n = 7), however, the number of circulating leu 7-positive cells was obviously increased. Statistically significant (p less than 0.01) was the increase in MM-pT (greater than 3 mm), compared to MM-pT.