Association between blood flow and inflammatory state in a T-cell transfer model of inflammatory bowel disease in mice

Background: Adoptive transfer of naive T-lymphocyte subsets into lymphopenic mice initiates chronic gut inflammation that mimics several aspects of inflammatory bowel disease (IBD). Patients with IBD can have profound alterations in intestinal blood flow, but whether the same is true in the T-cell transfer model has yet to be determined. Methods: In the current study, chronic intestinal inflammation was induced in recombinase-activating gene-1-deficient (RAG−/−) mice by adoptive transfer of CD4+ T-lymphocytes obtained from interleukin-10 deficient (IL-10−/−) mice. Results: Four weeks later, widespread colonic inflammation was observed in the reconstituted recipients, in contrast to 2 control sets of mice injected with a different subset of lymphocytes or with vehicle alone. We observed that the resulting pathology induced in the reconstituted RAG−/− mice was divided distinctly into 2 subsets: 1 with blood flow near normal with very high inflammation scores, and the other with severely attenuated blood flow but with much lower signs of inflammation. Colonic and ileal blood flow rates in the latter subset of CD4+ mice averaged only ≈30% compared to the mice with higher inflammation scores. The lower blood flow rates were associated with greatly reduced red blood cell concentrations in the tissue, suggesting a possible loss of vascular density. Conclusions: In this model of chronic intestinal inflammation, mild inflammation was associated with significant decreases in blood flow. Inflamm Bowel Dis 2009