Deletion Of Cd47 Protects From Murine Experimental Crohn'S Disease

established new model of antigen-specific transfer colitis we now show that CD44v7 expression on macrophages but not on T cells was crucial to protect mice from intestinal inflammation.Thus CD44v7 deleted recipient mice showed complete restoration of the gut mucosa, accompanied by decreased IFN-gamma and IL-17 secretion whereas antigen specific T cells, derived from D011.10 mice, mediated colitis after re-challenge In Vivo irrespective of CD44v7.In the CD44v7-/-recipient mice, significantly more FoxP3+ regulatory T cells were detected as compared to wild type recipients.In Vitro, coculture experiments with CD44v7-/-macrophages induced significantly more FoxP3+ regulatory T cells than wild type macrophages.LPS activation of wild type macrophages downregulated FoxP3+ T cells whereas CD44v7-/macrophages induced an upregulation of FoxP3.FoxP3+ regulatory T cells cocultured with CD44v7-/-macrophages showed a significantly higher suppressor potential compared to FoxP3+ regulatory T cells induced by wild type macrophages.Hence, in LPS-induced inflammation deletion of CD44v7 regulates tolerance induction.