Expression And Clinical Significance Of TLR4-MyD88-NF-kB Signal Pathway In Ulcerative Colitis

BackgroundInflammatory bowel disease(IBD)is a common gastrointestinal disease.There are mainly two forms of disease:Crohn’s disease(CD)and Ulcerative colitis(UC).The cause has not been clarified.Many scholars believe that the disease is related to the imbalance of the mucosal immune response mediated by microorganisms.Pattern recognition receptors(PRR)recognize specific molecular structures on the surface of pathogenic microorganisms and apoptotic cells.Damage-associated molecular pattern(DAMP)and Pathogen-associated molecular patterns(PAMP)both activate the innate immune response through PRR.Toll-like receptor(TLR)is a type of PRR.Previous research reports have shown that the immune response mediated by TLR is abnormally activated in the DSS-induced mouse colitis model,but there are few studies on its expression in the colon tissue of IBD patients,and further investigation is still needed.ObjectiveThe objective will investigate the expression of colonic biopsy tissue TLR4,MYD88,NF-KBP65,RORγand clarify the TLR-mediated inflammatory pathway and its downstream expression product with UC,furthermore analyze the relationship with clinical inflammatory indicators.Materials and Methods1.Collection of tissue specimens with UC:A total of 30 tissue samples of UC patients admitted to hospital or outpatient service from December 2019 to December2020 were collected,including 7 cases in remission stage,23cases in active stage,including 8 cases in mild stage,7 cases in moderate stage and 8 cases in severe stage.In addition,10 cases of cancerous specimens of patients with colorectal cancer were collected(more than 5 cm from carcinoma).2.Collecting the erythrocyte sedimentation rate and C-reactive protein during admission of UC patients.The correlation between ESR、CRP and the results of immunohistochemistry was analyzed.3.The data obtained in the study was analyzed by SPSS23.0 statistical software.In each group of patients,the quantitative expression level of each detection index,age,and disease course were expressed by the mean±standard deviation.In the negative control group,UC in remission period,mild UC and moderate to severe UC colon tissues,the expression of each index was compared by one-way analysis of variance;the correlation between the expression of each index and erythrocyte sedimentation rate and CRP was expressed by Spearman correlation analysis and scatter plot.P<0.05 shows that the difference was statistically significant.Results1.Analysis of HE staining in colonic tissue of patients with UCIn the negative control group,the structure of the tissue mucosa remained unchanged and the lamina propria was normal.In the biopsy tissue of UC patients,much inflammatory cell infiltration can be seen in the lamina propria of mucosa,the mucosal atrophy and the crypt structure changes and the number decreased。The epithelial cell structure was destroyed.The gland structure changes,even disappears.The plasma cell can be seen in the base layer.2.Expression of TLR4 in colonic tissue of patients with UCTLR4 is mainly expressed in the cell membrane in the colon tissue.Brown yellow particles represent positive.The expression of TLR4 was the highest in patients with moderate and severe group UC,followed by patients with mild group.In the negative control group and patients with UC in remission stage,TLR4’s expression was less and the color was weak.After quantifying the expression intensity,the expression score of TLR4 in moderate to severe UC patients was significantly higher than that in mild group,remission stage and negative control groups.The mild group was higher than that in remission and control groups(P<0.05),while there was no difference between in remission and control groups(P>0.05).3.Expression of MyD88 in colonic tissue of patients with UCMyD88 is mainly expressed in the cytoplasm of colon tissue.Brown yellow particles represent positive.The expression of MyD88 was the highest in patients with moderate and severe group UC,followed by patients with mild group.In the negative control group and patients with UC in remission stage,MyD88’s expression was less and the color was weak.After quantifying the expression intensity,the expression score of MyD88 in moderate to severe UC patients was significantly higher than that in mild group,remission stage and negative control groups.The mild group was higher than that in remission and control groups(P<0.05),while there was no difference between in remission and control groups(P>0.05).4.Expression of NF-kBp65 in colonic tissue of patients with UCNF-kBp65 is mainly expressed in the nucleus and cytoplasm,and brown yellow particles represent positive.A large number of brown-yellow stained areas can be seen in the colon tissue of patients with moderate and severe group,with the highest positive expression.The expression of NF-kBp65 in patients with mild group UC was low positive.In patients with UC in remission and the negative control group,the expression of NF-kBp65 was low and the color was weak.After quantifying the expression intensity,the expression score of NF-kBp65 in patients with moderate to severe UC was significantly higher than that in mild group,remission and negative control groups.Mild UC was higher than that in remission and negative control groups(P<0.05).There was no difference between UC in remission and the negative control group(P>0.05).5.Expression of RORγin colonic tissue of patients with UCRORγis mainly expressed in the nucleus of colon tissue cells,and brown yellow particles represent positive.The expression level of RORγwas the highest in the moderate and severe group,and the expression of RORγwas low in the mild group.In the control group and remission period,the expression of RORγprotein was less and the color was weak.After quantifying the expression intensity,the expression score of RORγin the moderate to severe UC was significantly higher than that of the mild group,remission period and the control group.Mild group was higher than that in remission and negative control groups(P<0.05),but there was no difference between the remission period and the control group(P>0.05).6.Correlation analysis between TLR4,MyD88,NF-kBp65,RORγand ESR and CRP in colonic tissue of patients with UC.The expression levels of TLR4(r_s=0.447,P<0.05),MyD88(r_s=0.453,P<0.05),NF-kBp65(r_s=0.490,P<0.05),RORγ(r_s=0.485,P<0.05)were positive correlated with ESR.The expression levels of TLR4(r_s=0.840,P<0.01),NF-kBp65(r_s=0.925,P<0.01),RORγ(r_s=0.831,P<0.01)were positive correlated with CRP.Conclusions1.The expression of TLR4,MYD88,NF-KBP65,RORγin colon tissues of patients with UC was enhanced and related to the severity of the disease.2.The expression of TLR4,NF-KBP65,RORγin colon tissues of patients with UC is positive correlated with erythrocyte sedimentation rate and CRP levels,and MYD88 is only positive correlated with erythrocyte sedimentation rate.