Effects of infliximab induced clinical remission of active Crohn's disease on the level of interleukin-21 and interleukin-21 receptor / 中华消化杂志

ABSTRACT

Objective To investigate the changes of interleukin-21 (IL 21) and interleukin-21 receptor (IL 21R) expression level in Crohn's disease (CD) patients before and after accepted infliximab (IFX) treatment.Methods From June 2009 to July 2011,twenty-two CD patients met the research criteria were recruited at Tenth People's Hospital of Tongji University.Patients were treated with infliximab at weeks 0,2,6,and 16 healthy individuals were set as healthy control group at same time.Peripheral blood of healthy control group was taken at regular physical examination and blood of CD patients was taken before treatment and 10 weeks after treatment,intestinal mucosa biopsy samples were taken under colon endoscopy examination.The changes of Crohn's disease activity index (CDAI),erythrocyte sedimentation rate (ESR),C-reactive protein (CRP) in CD patients were observed.The change of IL-21R in peripheral blood CD4+ T lymphocytes was detected by flow cytometry.The change of IL-21 expression at mRNA level in intestinal mucosa was determined by realtime quantitative polymerase chain reaction (PCR).The data were analyzed by t test.Results Before treatment,the level of IL21R in peripheral blood CD4+ T lymphocytes of CD patients (12.25％±3.25％) and the expression of IL-21 at mRNA level in inflamed intestinal mucosa (1.38±0.32) were both significantly higher than those of healthy controls (4.25 ％ ± 1.41％,0.44±0.18),the differences were statistically significant (F=15.88,6.75 ; both P＜0.05).At 10th week,the level of IL-21R in peripheral blood CD4+ T lymphocytes of CD patients (8.12％ ± 2.05％) and the expression of IL-21 at mRNA level in intestinal mucosa (0.77 ± 0.24) were both significantly lower than those before treatment,the differences were statistically significant ( t=4.880,8.019; both P＜0.01).Before treatment,ESR,CRP and CDAI of CD patients was (46.8±11.4) mm/1 h,(52.4±11.5) mg/L and 319±74,which was (23.5±9.0) mm/1 h,(11.6±4.6) mg/L and 113±42 after treatment,the differences were statistically significant (t=9.485,16.458,11.100; all P＜0.05).Conclusion The IL-21 expression of active CD patients decreases after IFX treatment,which indicates that IL-21 may involve in IFX induced clinical remission of active CD.