EXPRESSION OF GD3 DISIALOGANGLIOSIDE ANTIGEN ON PERIPHERAL T-LYMPHOCYTES IN PATIENTS WITH DISSEMINATED MALIGNANT-MELANOMA

Disialoganglioside antigens GD2 and GD3 are expressed on most melanoma cells. On melanoma surrounding T-cells in immunohistological sections , disialogangliosides can also be found, as well as in a small % of T- lymphocytes in peripheral blood from healthy persons. In order to find out if there is a difference in ganglioside expression on peripheral T-lymphocytes between melanoma patients and healthy persons, we examin ed the expression of CD3 as T-lymphocytic antigen and GD2 or GD3 antig ens, respectively, by flow cytometry. We used peripheral mononuclear b lood cells of 12 patients with advanced disseminated malignant melanom a and of 12 healthy control donors. For immunostaining, murine monoclo nal antibodies Leu-4, 14G2a and MB3.6 were used, recognizing CD3, GD2 and GD3. GD2 expression was found on only a low proportion of T-lympho cytes in patients and healthy persons (pat.: mean=1.2%+/-0.7%, co.: me an=0.4%+/- 0.4%). Disialoganglioside antigen GD3, however, could be de monstrated on an average of 8.4%+/-4.6% of patients' and on 4.0%+/-2.1 % of healthy persons' T-cells. There is a statistically significant di fference (P<0.01) between the data of patients' and control group. We conclude that there is a correlation between advanced malignant melano ma and expression of GD3 antigen on patients' peripheral T-lymphocytes . The immunological relevance of our findings is discussed.