More Active Intestinal Immunity Developed by Obese Mice Than Non-Obese Mice After Challenged by.

Abstract

Obese mice presented lower mortality to non-fatal pneumonia induced by() than the non-obese mice. However, it remained obscure whether the intestine contributed to the protective effect of obese mice with infection. The 64 non-obese (NOB) mice were divided into NOB-uninfected and NOB-groups, while 64 high-fat diet-induced obesity (DIO) mice were divided into DIO-uninfected and DIO-groups. Mice ingroups were intranasally instilled with 40 &#x3bc;l(4.0 &#xd7;10colony-forming units [CFUs]), while uninfected groups with the same volume of phosphate buffer saline (PBS). The T subsets of Intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) in the intestine were collected for flow cytometry analysis at 0, 12, 24, and 72 h post-infection, also the duodenum and colon were harvested to survey histopathological change. The results showed that the percentage of CD3T cells in LPLs in DIO-group was significantly lower than that in the DIO-uninfected group after infection (< 0.05). The percentage of CD4T cells in IELs in NOB-was significantly lower than that in DIO-after infection (< 0.05). The percentage of CD8T cells in LPLs in NOB-was significantly lower than that in DIO-at 12 and 24 h (< 0.05). The immunoglobulin A (IgA)cells in DIO-uninfected were higher than that in NOB-uninfected at all time points (< 0.05). The IgAcells in DIO-were higher than that in DIO-uninfected at 12, 24, and 72 h (< 0.05). The results revealed that the level of intestinal mucosal immunity in obese mice was more active than that in non-obese mice.