IL-10-deficient mice develop spontaneous colitis, a disease due to chronic inflammation in the gastrointestinal (GI) tract. However, when these mice are housed in germ-free conditions, in which they lack all commensal microbes in their GI tract, no colitis was observed. In addition, one would expect germ-free IL-10-deficient mice to also show: A) Evidence of enhanced systemic immune activation compared to conventionally housed il10^-/- mice B) Enlarged mesenteric lymph nodes compared to conventionally housed il10^-/^- mice C) Elevated numbers of FoxP3+ T cells in the lamina propria compared to conventionally housed il10^-/- mice D) Increased production of IgG antibodies compared to conventionally housed il10^-/- mice E) Reduced production of IgA antibodies compared to conventionally housed il10^-/- mice

Question

Quizplus · Accepted Answer

Germ-free conditions lead to reduced exposure to antigens, which would normally stimulate the production of IgA antibodies in the gut to protect against pathogens. Since IL-10-deficient mice in germ-free conditions lack commensal microbes, there would be less need for IgA production, resulting in reduced IgA antibody levels compared to those housed in conventional conditions with normal microbial exposure.

IL-10-Deficient Mice Develop Spontaneous Colitis, a Disease Due to Chronic