title: Lack of suppressive activity of human primary melanoma cells on the activation of autologous lymphocytes.
abstract: Previous studies have indicated that primary but not metastatic melanomas were able to stimulate the proliferation of autologous (Auto) peripheral blood lymphocytes (PBL) in 73% of cases. On the other hand, 57% of the metastatic melanomas were shown to be suppressive when melanoma cells (Me) were admixed with Auto-PBL stimulated with allogeneic (Allo) PBL or interleukin 2 (IL-2) at the beginning of a 6-day incubation period. Here, we report that the suppressive activity of Me is a functional characteristic associated with a particular stage of the disease. In fact, we found that none of the 11 primary tumors tested were able to inhibit the proliferative response of Auto-PBL to Allo-PBL or IL-2 at all the doses of tumor cells used. The generation of lymphocytes cytotoxic against Auto-Me or K562 was also not inhibited. Of the 11 primary tumors checked for suppression, 8 were able to stimulate Auto-PBL in a primary mixed lymphocyte tumor culture. We conclude that opposite functions, stimulation and inhibition of autologous lymphocyte responses are characteristics of primary and metastatic Me, respectively.
authors.affiliation: Department of Experimental Medicine, University of Rome La Sapienza, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Taramelli
authors.forename: A
authors.initials: A
authors.lastname: Mazzocchi
authors.forename: C
authors.initials: C
authors.lastname: Clemente
authors.forename: G
authors.initials: G
authors.lastname: Fossati
authors.forename: G
authors.initials: G
authors.lastname: Parmiani
mesh_terms: D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology; D008545:Melanoma / Q000276:immunology / Q000473:pathology* / Q000556:secondary; D014407:Tumor Cells, Cultured / Q000276:immunology / Q000637:transplantation