Dietary porcine plasma protein attenuates inflammatory severity in the mdr1a-/- mouse model of colitis.

We have previously shown that spray-dried plasma (SDP) can modulate the immune response in a rat model of acute intestinal inflammation. We now examine the effects of SDP in mdra1-/- (KO) mice lacking the multiple drug resistance gene, that develop spontaneous colitis Animals were supplemented with SDP (8% w/w) or milk proteins (Control) from weaning until day 56. The permeability of the colon mucosa was analysed at functional and structural levels. The expression of different cytokines and the percentages of activated and regulatory T cells were also determined. Colonic permeability was increased in KO mice (P<0.05) in this was prevented by SDP supplementation (P<0.05). KO mice showed increased percentage of activated Th lymphocytes (P<0.05) that was attenuated by SDP (P<0.05). The expression of cytokines (TNFα, IFNγ, IL2, IL17), chemokines (MCP1, MIP1b) and iNOS in the colon was significantly increased but SDP could reduce them by 15-50% (P<0.05). Interestingly, SDP increased the expression of mucosal IL10 (P<0.05) as well as the percentage of regulatory Th lymphocytes in the lamina propria (P<0.05). We conclude that dietary supplementation with SDP is able to prevent in part the changes observed in the colon of mdr1 a KO mice during the development of colitis.