Abstract
Gene expression in peripheral blood mononuclear cells (PBMCs) isolated from subjects before and after a 3-week walnut supplementation was examined for differentially expressed genes by RNA-seq. Significant gene expression changes were observed following walnut consumption with gene enrichment analysis showing significant overlap with genes previously associated with a robust memory B cell response following vaccination. An in-depth clustering analysis of the data revealed that a relatively large subpopulation of the subjects (11/19) showed a stronger and more uniform response to walnut consumption. This group of individuals showed an even more extensive overlap with genes associated with memory B cell production, with a significant overlap also observed for genes activated by an influenza vaccine adjuvant. The genes altered by walnut included numerous kinases and transcription factors, yet a deconvolution analysis did not reveal changes in the major PBMC cell types. Our findings show that a walnut supplementation can change gene expression in PBMCs in a manner consistent with a more responsive adaptive immune response without affecting the cellular composition of the blood.