ETHANOL ACTIVATES IMMUNE RESPONSE IN LYMPHOBLASTOID CELLS

The short term effects of alcohol on gene expression in brain tissue cannot directly be studied in humans. Because neuroimmune signaling is altered by alcohol, immune cells are a logical, accessible choice to study and might provide biomarkers. RNAseq was used to study the effects of 48 h exposure to ethanol on lymphoblastoid cell lines (LCLs) from 20 alcoholics and 20 controls. Ethanol exposure resulted in differential expression of 4,577 of the 12,526 genes detectably expressed in the LCLs (FDR = 0.05); 55% of these showed increased expression. Cells from alcoholics and controls responded similarly. Ingenuity pathway analysis identified several pathways in which expression was altered: NFkB, neuroinflammation, IL8, and dendritic cell maturation pathways were activated, consistent with increased signaling by NFkB, TNF, IL1, IL4, IL18, TLR4, and LPS. Signaling by Interferons A and B decreased, as did EIF2 signaling, phospholipase C signaling and Glycolysis. Baseline gene expression patterns were similar in LCLs from alcoholics and controls. At relaxed stringency (p<0.05), 438 genes differed, 223 of which were also affected by ethanol. There was a suggestion of compensation because baseline differences (no ethanol) were in the opposite direction of differences due to ethanol exposure in 75% of these genes. Ingenuity Pathway analysis Identified pathways wAldosterone, phospholipase C, and opioid signaling as significant. The pattern of expression was consistent with increased signaling by several cytokines including interferons, and TLR2 and 3 in alcoholics. Expression of genes in the cholesterol biosynthesis pathway including the rate-limiting enzyme HMGCR was lower in alcoholics. Overall design: LCLs from 20 alcoholics and 20 controls treated or not with 75mM ethanol for 48h