Background: While a method of assaying natural killer (NK) cell activity by measuring the amount of interferon (IFN)-γ released from NK cells has been proposed, no data are available about the factors that influence IFN-γ levels related to NK cell activity. NLR has recently been reported to be a predictor of several diseases. In the present study, we investigated the pre-analytical variables for NK cell activity using measurements of IFN-γ and the relationship between NLR and NK cell activity.
Methods: The NK cell activity was assessed with the measurement of IFN-γ after stimulation with an NK cell-specific stimulant (NK Vue™ , ATgen, Sungnam, Korea). One hundred and six adult volunteers were recruited and analysis of their complete blood count data and serum C-reactive protein was done. Blood sample from 59 of the participants was also used for analysis of lymphocyte subpopulations.
Result: Natural killer cell activity varied widely (range, 44.2-1775.6 pg/mL). NK cell activity was higher in females than in males (P = 0.014). NK cell activity decreased with increasing NLR (P = 0.004, r = -0.32) but NK cell activity showed no significant association with NK cell count or other lymphocyte subpopulations. NK cell activity levels according to CRP quartile were significantly different (P = 0.025).
Conclusion: We have observed that NK cell activity when assessed by IFN-γ level measurement was negatively correlating with NLR. This result can be helpful in interpreting or predicting NK cell activity in the clinical environment.
Keywords: NK cell; NK cell activity; immunoregulation; interferon gamma; neutrophil-to-lymphocyte ratio.
© 2018 Wiley Periodicals, Inc.