title: Intestine-specific overexpression of IL-10 improves survival in polymicrobial sepsis.
abstract: Targeted IL-10 therapy improves survival in preclinical models of critical illness, and intestine-specific IL-10 decreases inflammation in models of chronic Inflammatory disease. We therefore sought to determine whether intestine-specific overexpression of IL-10 would improve survival in sepsis. Transgenic mice that overexpress IL-10 in their gut epithelium (Fabpi-IL-10 mice) and wild-type (WT) littermates (n = 127) were subjected to cecal ligation and puncture with a 27-gauge needle. The 7-day survival rate was 45% in transgenic animals and 30% in WT animals (P < or = 0.05). Systemic levels of IL-10 were undetectable in both groups of animals under basal conditions and were elevated to a similar degree in septic animals regardless of whether they expressed the transgene. Local parameter of injury, including gut epithelial apoptosis, intestinal permeability, peritoneal lavage cytokines, and stimulated cytokines from intraepithelial lymphocytes, were similar between transgenic and WT mice. However, in stimulated splenocytes, proinflammatory cytokines monocyte chemoattractant protein 1 (189 +/- 43 vs. 40 +/- 8 pg/mL) and IL-6 (116 +/- 28 vs. 34 +/- 9 pg/mL) were lower in Fabpi-IL-10 mice than WT littermates despite the intestine-specific nature of the transgene (P < 0.05). Cytokine levels were similar in blood and bronchoalveolar lavage fluid between the 2 groups, as were circulating LPS levels. Transgenic mice also had lower white blood cell counts associated with lower absolute neutrophil counts (0.5 +/- 0.1 vs. 1.0 +/- 0.2 10(3)/mm3; P < 0.05). These results indicate that gut-specific overexpression of IL-10 improves survival in a murine model of sepsis, and interactions between the intestinal epithelium and the systemic immune system may play a role in conferring this survival advantage.
authors.affiliation: Department of Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: Saju
authors.initials: S
authors.lastname: Rajan
authors.forename: Dinesh
authors.initials: D
authors.lastname: Vyas
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Clark
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Woolsey
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Clark
authors.forename: Richard S
authors.initials: RS
authors.lastname: Hotchkiss
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Buchman
authors.forename: Craig M
authors.initials: CM
authors.lastname: Coopersmith
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D004731:Endotoxins / Q000494:pharmacology; D005838:Genotype; D007150:Immunohistochemistry; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018805:Sepsis / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D013154:Spleen / Q000166:cytology / Q000378:metabolism; D016019:Survival Analysis; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D004731:Endotoxins; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10