Quantitative proteomic analysis of host epithelial cells infected by Salmonella enterica serovar Typhimurium.

Systems-level analyses have the capability to offer new insight into host-pathogen interactions on the molecular level. Using Salmonella infection of host epithelial cells as a model system, we previously analyzed intracellular bacterial proteome as a window into pathogens' adaptations to their host environment [Infect. Immun. 2015; J. Proteome Res. 2017]. Herein we extended our efforts to quantitatively examine protein expression of host cells during infection. In total, we identified more than 5000 proteins with 194 differentially regulated proteins upon bacterial infection. Notably, we found marked induction of host integrin signaling and glycolytic pathways. Intriguingly, up-regulation of host glucose metabolism concurred with increased utilization of glycolysis by intracellular Salmonella during infection. In addition to immunoblotting assays, we also verified the up-regulation of PARP1 in the host nucleus by selected reaction monitoring and immunofluorescence studies. Furthermore, we provide evidence that PARP1 elevation is likely specific to Salmonella infection and independent of one of the bacterial type III secretion systems. Our work demonstrates that unbiased high-throughput proteomics can be used as a powerful approach to provide new perspectives on host-pathogen interactions.