Analysis of the natural killer mediated immune response in metastatic renal cell carcinoma patients

Metastatic renal cell carcinomas (MRCC) are considered as immunogeneic tumors on the basis of the clinical responses observed in patients treated by IL-2. However, renal cell carcinoma patients are also characterized by alterations of the immune response that may compromise the immunotherapeutic approaches. In our study, we have studied the phenotype and the functional capacities of peripheral NK cells in a panel of neprectomized metastatic renal cell carcinoma patients. NK cells were harvested by negative immunoselection from fresh peripheral blood samples. In most of MRCC patients analysed (23/28), the expression of NCR (NKp46 and NKp30) was similar to that of donors. Lytic capacities by activated immunoselected NK cells from MRCC patients assessed against K562 and 3 renal tumor cell lines were in the range of that observed in NK cells from normal donors. FILA-1^- renal tumor cells UOK23 were killed with a good efficiency, whereas HLA-1 renal tumor cells were more resistant. Although LFA-1/ICAM-1 interaction potentiates RCC cell lysis, HLA-1/NKR interaction clearly decreased RCC cell susceptibility to NK cells. In addition, proliferation of NK cells from MRCC patients in response to cytokines was altered.