title: Colitis development during the suckling-weaning transition in mucin Muc2-deficient mice.
abstract: The mucin Muc2 is the structural component of the colonic mucus layer. Adult Muc2 knockout (Muc2(-/-)) mice suffer from severe colitis. We hypothesized that Muc2 deficiency induces inflammation before weaning of mother's milk [postnatal day (P) 14] with aggravation of colitis after weaning (P28). Muc2(-/-) and wild-type mice were killed at embryonic day 18.5 and P1.5, P7.5, P14, P21, and P28. Colonic morphology, influx of T cells, and goblet cell-specific protein expression was investigated by (immuno)histochemistry. Cytokine and Toll-like receptor (TLR) profiles in the colon were analyzed by quantitative RT-PCR. Muc2(-/-) mice showed an increased and persistent influx of Cd3ε-positive T cells in the colonic mucosa as of P1.5. This was accompanied by mucosal damage at P28 in the distal colon but not in the proximal colon. At P14, the proinflammatory immune response [i.e., increased interleukin (IL)-12 p35, IL-12 p40, and tumor necrosis factor-α, expression] in the distal colon of Muc2(-/-) mice presented with an immune suppressive response [i.e., increased Foxp3, transforming growth factor (TGF)-β1, IL-10, and Ebi3 expression]. In contrast, at P28, a proinflammatory response remained in the distal colon, whereas the immune suppressive response (i.e., Foxp3 and TGF-β1 expression) declined. The proximal colon of Muc2(-/-) mice did not show morphological damage and was dominated by an immune suppressive response at P14 and P28. Interestingly, changes in expression of TLRs and TLR-related molecules were observed in the distal colon at P14 and P28 and in the proximal colon only at P28. Colitis in Muc2(-/-) mice is limited before weaning by immune suppressive responses and exacerbates in the distal colon after weaning because of the decline in the immune suppressive response.
authors.affiliation: Laboratory of Pediatrics, Rotterdam, The Netherlands.
authors.forename: Nanda
authors.initials: N
authors.lastname: Burger-van Paassen
authors.forename: Maria
authors.initials: M
authors.lastname: van der Sluis
authors.forename: Janneke
authors.initials: J
authors.lastname: Bouma
authors.forename: Anita M
authors.initials: AM
authors.lastname: Korteland-van Male
authors.forename: Peng
authors.initials: P
authors.lastname: Lu
authors.forename: Isabelle
authors.initials: I
authors.lastname: Van Seuningen
authors.forename: Günther
authors.initials: G
authors.lastname: Boehm
authors.forename: Johannes B
authors.initials: JB
authors.lastname: van Goudoever
authors.forename: Ingrid B
authors.initials: IB
authors.lastname: Renes
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D003092:Colitis / Q000209:etiology* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D003106:Colon / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D020397:Goblet Cells / Q000502:physiology; D006130:Growth Disorders / Q000209:etiology; D016753:Interleukin-10 / Q000096:biosynthesis; D007378:Interleukins / Q000096:biosynthesis; D051379:Mice; D018345:Mice, Knockout; D055262:Mucin-2 / Q000172:deficiency*; D055264:Mucin-4 / Q000096:biosynthesis; D009077:Mucins / Q000096:biosynthesis; D053594:Myeloid Differentiation Factor 88 / Q000096:biosynthesis; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis; D000071165:Trefoil Factor-3; D014886:Weaning
chemical_list: D007378:Interleukins; C524659:Muc4 protein, mouse; D055262:Mucin-2; D055264:Mucin-4; D009077:Mucins; C507780:Myd88 protein, mouse; D053594:Myeloid Differentiation Factor 88; C493263:Tff3 protein, mouse; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2; D000071165:Trefoil Factor-3; D016753:Interleukin-10