[A study of effective administration of recombinant interferon-gamma in renal cell carcinoma regarding immunological...

Immunological effect of recombinant interferon gamma (IFN-gamma) was studied in 18 cases of renal cell carcinoma. Sixteen of them were administered IFN-gamma as post-operative adjuvant therapy. Two of them were administered IFN-gamma for metastatic renal cell carcinoma. All of them were followed for at least 1 year. We divided the patients into two groups. One group subcutaneously received IFN-gamma every other day for 16 days, then 4 weeks later every week for one year (group A), and the other group, received alternate subcutaneous IFN-gamma every other day for 16 days and every week for 4 weeks (group B). For immunological testing, peripheral blood lymphocytes were obtained before treatment on day 1, 2 weeks later, 6 months later and 12 months later. The cells were tested for natural killer activity (NK), antibody dependent cellular cytotoxicity (ADCC), positive lymphocytes of CD3, CD4, CD8 and CD11b. Both ADCC and NK activity were increased after therapy, especially in group B. CD3, CD4 and CD8 positive lymphocytes were increased by means of IFN-gamma. On the other hand, CD11b-positive lymphocytes could not be elicited in group B. Tumor regression was observed in 2 cases of metastatic renal cell carcinomas. When clinical responses were observed, both ADCC and NK were elicited as compared with the pretreatment values. Our findings indicated that ADCC and NK could be elicited in group B.