An interaction map of circulating metabolites, immune-related gene networks and their genetic regulation (#35)
The interaction between metabolism and the immune system plays a central role in many cardiometabolic diseases. However, the extent to which this interplay contributes to disease risk in natural populations remains largely unknown. Here, we integrated blood transcriptomic, metabolomic, and genomic profiles from two population-based cohorts (combined N=2,168), including a subset of 333 individuals with follow-up sampling after seven years. Through gene co-expression network analysis, we identified networks enriched for diverse immune functions including cytotoxicity, viral response, B cell, platelet, neutrophil, and mast cell/basophils related activity, which topologically replicated between cohorts. We then performed association analysis of these 8 immune-related modules with 158 circulating metabolites and CRP, showing that each of these modules were significantly associated with diverse metabolites including lipoprotein subclasses, lipids, fatty acids, amino acids, and CRP. Further, for five of these modules, genome-wide scans revealed module expression quantitative trait loci with both cis and trans effects. The strongest module QTL was rs1354034, intronic to ARHGEF3, which affected the platelet activity module (meta-P-value = 7.35 x 10-28). Finally, we assessed the long-term stability of these interactions, finding that the metabolite associations for a mast cell and basophil-related module and the trans QTL effects of rs1354034 were largely maintained over a seven-year period. Taken together, this study provides a detailed map of natural variation at the immuno-metabolic interface in human blood and its genetic basis. The catalogue of immunometabolic interactions presented here may help explain differential disease susceptibility between individuals and guide subsequent mechanistic experiments.