Effects of gene silence on immune function of colonic dendritic cells in rats with irritable bowel syndrome visceral hypersensitivity / 中华消化杂志

ABSTRACT

Objective To explore the role and mechanism of protein disulfide isomerase A3 (PDIA3) in abnormal colonic mucosa immune response of irritable bowel syndrome (IBS) rats with visceral hypersensitivity.Methods A total of 48 SD rats were divided into blank control group (n=12),empty virus group (IBS-1) (n=12),PDIA3 silencing group (IBS-2) (n=12) and model control group(IBS-3) (n=12).The expression of CD103 in ileocecus colonic tissues was detected by immunohistochemistry.Dendritic cells (D C) of mesenteric lymph node were isolated by flow cytometry.CD4+/CD8+ T cells of spleen were separated by immune-magnetic beads sorting technique.DC and CD4+/CD8+ T cells were co-cultured.The proliferation ability of lymphocytes promoted by DC was measured by methyl thiazolyl tetrazolium (MTT).The secretion levels of interlcukin (IL) 4 and IL-9 of CD4+/CD8+ T cells stimulated by DC were determined by enzyme linked immunosorbent assay (ELISA) method.Independent sample t-test was performed for statistical analysis.Results The cell number of CD103 positive DC of rats colon of blank control group,IBS-3 group was 6.25±1.14 and 10.83± 1.03(t=10.07,P＜0.05);that of IBS-2 group was 7.42 ± 0.90,and compared with that of IBS-3 group,the difference was statistically significant (t=-9.25,P ＜ 0.05).The MTT value of CD4+ T cells proliferation stimulated by DC of blank control group and IBm3 group was 0.54±0.01 and 0.60±0.01 (t=3.373,P＜0.05);that of IBS-2 group was 0.53±0.01,and compared with that of IBS-3 group,the difference was statistically significant (t =-3.139,P ＜ 0.05).The MTT value of CD8+ T cells proliferation stimulated by DC was 0.52±0.01 and 0.59±0.00(t=3.539,P＜0.01);that of IBS-2 group was 0.54±0.01,and compared with that of IBS-3 group,the difference was statistically significant (t=-3.183,P＜0.05).The level of IL-4 secreted by CD4+T cells promoted by DC of blank control group and IBS-3 group was 10.24±0.09 and 16.61±1.00 (t=3.222,P＜0.05);that of IBS-2 group was 11.75±0.54,and compared with that of IBS-3 group,the difference was statistically significant (t=-3.539,P＜0.01).The level of IL-9 secreted by CD4+T cells stimulated by DC of blank control group and IBS-3 group was 15.86±10.19 and 43.51±11.32 (t=4.529,P＜0.05);that of IBS-2 group was 29.05±2.09,and compared with that of IBS-3 group,the difference was statistically significant (t=-6.841,P＜0.01).The level of IL-4 secreted by CD8+T cells promoted by DC of blank control group and IBS-3 group was 7.35±0.12 and 13.91±0.57 (t=19.557,P＜0.01);that of IBS-2 group was 8.63± 0.24,and compared with that of IBS-3 group,the difference was statistically significant (t =-14.782,P＜0.01).The level of IL-9 secreted by CD8+T cells stimulated by DC of blank control group and IBS-3 group was 29.12±5.14 and 60.70±11.02 (t=4.122,P＜0.05);that of IBS-2 group was 37.17±2.65,and compared with that of IBS-3 group,the difference was statistically significant (t=-3.255,P＜ 0.05).Conclusions Protein disulfide isomerase A3 may mediate the process of DC activating T lymphocyte levels of related cytokines,cause abnormal immune response of colonic mucosa and promote the genesis of IBS visceral hypersensitivity.