Symposium on the health effects of gasoline: panel discussion on the state of the science.

The phenotype of peripheral blood lymphocytes of 27 renal cell carcinoma patients before and at the end of subcutaneously given rIL-2 therapy was determined by two colour flow cytometry. Therapy induced changes in peripheral blood leucocyte composition and phenotypes were comparable to those reported for intravenously given rIL-2. The present paper shows a correlation between the 'activation status' of the patient before therapy and eventual response. The therapeutical effects of recombinant interleukin-2 (rIL-2) therapy look promising in the case of renal cell carcinoma (RCC) and melanoma (Rosenberg et al., 1987; West et al., 1987). Most of the interleukin-2 therapies so far, involved the intravenous administration of high dose rIL-2, causing severe side effects. In our clinic, rIL-2 was administered subcuta-neously (s.c.) which avoided severe side effects, whereas clinical results were comparable to the ones involving intravenous (i.v.) administration of rIL-2 (Sleijfer et al., 1990; 1992). The immunomodulatory effects of subcutaneously administered rIL-2 still remain to be investigated. The present paper gives data on the 'activation status' of the main peripheral blood lymphocyte subpopulations (helper T cells, cytotoxic T cells and NK cells) in 27 RCC patients by determining the expression of the activation marker HLA-Dr on these lymphocytes before and after s.c. rIL-2 therapy (day 35 and day 40).