title: Role of dendritic cell-mediated abnormal immune response in visceral hypersensitivity.
abstract: The role of dendritic cells (DCs) in irritable bowel syndrome (IBS) is unclear. This study tested the hypothesis that intestinal DCs induced visceral hypersensitivity in IBS rats through mast cell (MC) activation. The IBS rat model was established by combining colorectal distension with restraint stress. The number of CD103-positive cells in colon was higher in the IBS group. Expression of PAR-2, IL-4 and IL-9 in the colonic mucosa was higher in the IBS group. Mesenteric lymph node DCs (MLNDCs) and splenic CD4(+)/CD8(+) T cells were isolated and purified by a magnetic labeling-based technique; they were cultured alone or co-cultured (T4+DC/T8+DC). The coculture of MLNDCs and CD4(+) T cells had the highest IL-4 secretion in the IBS group, while IL-9 expression was higher in the cultures containing CD8(+) T cells. Our findings indicate that an increased number of DCs in the colon stimulated CD4(+) T cells to secrete high levels of IL-4, which led to the activation of MCs and subsequently resulted in visceral hypersensitivity.
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Meng
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Bin
authors.initials: B
authors.lastname: Lu
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Li
authors.initials: L
authors.lastname: Chu
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Lina
authors.initials: L
authors.lastname: Meng
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006, P R China.
authors.forename: Yihong
authors.initials: Y
authors.lastname: Fan
keywords: Immune; dendritic cells; visceral hypersensitivity