Further evidence for depletion of peripheral blood natural killer cells in patients with schizophrenia: A computational deconvolution study.

Dysregulation of innate and adaptive immunity is increasingly being recognized as one of core characteristics of schizophrenia pathophysiology. Several studies have revealed that patients with schizophrenia present various alterations in the levels of distinct leukocyte subpopulations. However, studies addressing this point have provided mixed results. Therefore, in this study we translated a computational deconvolution algorithm in order to estimate counts of distinct leukocyte subpopulations in peripheral blood of patients with schizophrenia. Our analysis was based on publicly available data from peripheral blood DNA methylation profiling in 711 schizophrenia patients and 713 healthy controls (2 independent samples). In both datasets, there were significantly lower levels of CD8 and NK cells together with significantly higher levels of granulocytes. However, the levels of CD8 cells were insignificant after controlling for age and sex differences in one dataset. Our results indicate that patients with schizophrenia present innate immunity dysregulation in terms of NK cells depletion and increased levels of granulocytes. Longitudinal studies of various clinical subgroups of schizophrenia patients are required in order to disentangle whether our findings reflect trait- or state-dependent alterations.