Single-cell transcriptomic analysis of PBMCs derived from salmonella-challenged pigs 2681

Abstract Description Foodborne Salmonella is a human health concern through consumption of contaminated products. However the pig immune response to Salmonella is minimally understood. To delineate the cell-type specific immune response toSalmonella, we used scRNA-seq analysis of peripheral blood mononuclear cells(PBMCs, n = 103,075) collected from five young pigs inoculated with Salmonella enterica serovar I 4,{5},12:i:- at day 0, 2 and 8. Nine major cell types were identified, including monocytes, pDCs, B, T, and NK cells. Differentially expressed (DE) genes were identified due to time after infection in many cell types. Gene ontology (GO) enrichment analysis of DE genes identified immune response-associated GO terms. For genes DE at day 2 versus day 0, examples (n=DEGs) include monocytes (4,718) with significant positive enrichment (SPE) of “innate immune response”; pDCs (48) had SPE of “negative regulation of viral process”; B cells (5,880) had SPE of “response to bacterium”; and CD4+ T cells (7,753) had SPE of “cellular response to cytokine stimulus”. DE genes in monocytes (d8/d2, n = 7,148) had significant depletion of the GO term “regulation of innate immune response”. We also have preliminary evidence of differential abundance of monocytes and other cell types at day 2 versus 0, which had substantially returned to baseline by day 8. Cell-type specific transcriptomic responses to Salmonella in porcine PBMCs can be mined to identify pathways for targeted enhancement of host response. Funding Sources USDA –NIFA AFRI Grant 2022-67015-37055 Topic Categories Veterinary and Comparative Immunology (VET)