Objective: To investigate in vitro natural killer (NK) cell activity and expression of signal-transducing zeta chains in patients with cervical cancer.
Patients and methods: Experiments were performed with frozen lymphocytes from patients at all disease stages and from healthy controls. Thawed NK were activated by overnight incubation in interferon-gamma (IFN-gamma); activity against two target cell lines was assessed by 4-h (51)Cr release assay. Targets chosen were K562, an erythroleukemic cell line, and a cervical carcinoma cell line designated 808. T and NK cell zeta chain expression was measured by flow cytometry.
Results: Patients' NK were found to be as cytotoxic as those of normal controls against cell lines K562 and 808. Patient T and NK cells did not show significant down-regulation of the zeta chain.
Conclusions: We have found no evidence to suggest that loss of zeta chains is a mechanism for immunocompromise in patients with cervical carcinoma. IFN-recoverable patient NK activity is not reduced compared to matched controls. This may be clinically relevant since NK are active against cells exhibiting class I human leukocyte antigen (HLA) down-regulation and many cervical cancers show loss of HLA.