CD3+ CD56+ NKT-like cells have been shown to produce substantial amounts of pro-inflammatory cytokines and to mediate lysis of malignant cells. Using flow cytometry, we evaluated the absolute NKT-like cell count in peripheral blood from individuals in a reference population and the median number was 0.085 x 10(9)/l. The average number of NKT-like cells in patients with disseminated cancer was 2.65 fold higher than in the reference population. The number of CD3+ CD56+ cells in solid tumour patients who achieved complete remission was comparable to the reference population. In breast cancer patients with initially (prior to therapy) increased number of NKT-like cells, we observed a trend toward longer disease-free survival. Thus we conclude that CD3+ CD56+ NKT-like cells have potential to suppress tumour evasion and are expanded in peripheral blood of some epithelial tumour patients.

Department of Laboratory Medicine Masaryk Memorial Cancer Institute Brno Czech Republic

Assessment of Immune Response Following Dendritic Cell-Based Immunotherapy in Pediatric Patients With Relapsing Sarcoma