M2 Polarization and Inhibition of Host Cell Glycolysis Contributes Intracellular Survival of Salmonella Strains in Chicken Macrophage HD-11 Cells

Salmonella is a group of facultative, gram-negative bacteria. Recently, new evidence indicated that could reprogram the host metabolism to increase energy or metabolites available for intracellular replication. In this study, using a chicken-specific kinomic immunometabolism peptide array analysis, we found that infection by Enteritidis induced significant phosphorylation changes in many key proteins of the glycolytic pathway in chicken macrophage HD-11 cells, indicating a shift in glycolysis caused by infection. Nitric oxide production and changes of glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) represented by extracellular acidification rate (ECAR) and oxygen consumption rate (OCR), respectively, were measured in chicken macrophages infected with three strains ( . Enteritidis, Heidelberg, and . Senftenberg). The infection reduced glycolysis and enhanced OXPHOS in chicken macrophages as indicated by changes of ECAR and OCR. strains differentially affected macrophage polarization and glycolysis. Among three strains tested, . Enteritidis was most effective in downregulating glycolysis and promoting M2 polarization as measured by ECAR, ORC, and NO production; while . Senftenberg did not alter glycolysis and may promote M1 polarization. Our results suggested that downregulation of host cell glycolysis and increase of M2 polarization of macrophages may contribute to increased intracellular survival of Enteritidis.