Title Pten gene deletion in intestinal epithelial cells enhances susceptibility to Salmonella Typhimurium infection in mice
Author Cody Howe1, Jonathon Mitchell1, Su Jin Kim1,2, Eunok Im1,2, and Sang Hoon Rhee1,3
Address 1Department of Biological Sciences, Oakland University, Rochester, Michigan, 48309, USA, 2College of Pharmacy, Pusan National University, Busan 46241, Republic of Korea, 3Division of Digestive Diseases, David Geffen School of Medicine, University of California Los Angeles, CA, 90095, USA
Bibliography Journal of Microbiology, 57(11),1012–1018, 2019,
DOI 10.1007/s12275-019-9320-3
Key Words immune responses, intestinal epithelial cells, Pten, Toll-like receptor
Abstract Although phosphatase and tensin homolog (PTEN) is typically considered a tumor-suppressor gene, it was recently suggested that PTEN regulates TLR5-induced immune and inflammatory responses in intestinal epithelial cells (IECs), suggesting an immunomodulatory function of PTEN in the gut. However, this alternative function of PTEN has not yet been evaluated in an in vivo context of protection against enteropathogenic bacteria. To address this, we utilized IECrestricted Pten knockout (PtenΔIEC/ΔIEC) and littermate Pten+/+ mice. These mice were subjected to the streptomycin-pretreated mouse model of Salmonella infection, and subsequently given an oral gavage of a low inoculum (2 × 104 CFU) of Salmonella enterica serovar Typhimurium (S. Typhimurium). This bacterial infection not only increased the mortality of PtenΔIEC/ΔIEC mice compared to Pten+/+ mice, but also induced deleterious gastrointestinal inflammation in PtenΔIEC/ΔIEC mice manifested by massive histological damage to the intestinal mucosa. S. Typhimurium infection upregulated pro-inflammatory cytokine production in the intestine of PtenΔIEC/ΔIEC mice compared to controls. Furthermore, bacterial loads were greatly increased in the liver, mesenteric lymph node, and spleen of PtenΔIEC/ΔIEC mice compared to controls. Together, these results suggest that IEC-restricted Pten deficiency renders the host greatly susceptible to Salmonella infection and support an immuneregulatory role of PTEN in the gut.