Preliminary research of B10 cell infiltration in the anastomotic tissue of the choledochojejunostomy rat model / 国际外科学杂志

ABSTRACT

Objective:To investigate the infiltration of B10 cells in the anastomotic tissue after choledochojejunostomy by establishing a rat model of choledochojejunostomy.Methods:24 male SPF SD rats aged 6 weeks and weighing 180-200 g were randomly divided into control group, 1-week group, 2-week group and 4-week group, with 6 samples in each group. The rats were killed at different time after operation to obtain the anastomotic tissue and peripheral blood. The changes of anastomotic diameter were measured. The changes of inflammatory factors in peripheral blood were determined by ELISA. Flow cytometry was used to detect the proportion of B10 cells in peripheral blood and tissues around the anastomotic site. The formation of anastomotic scar was evaluated by histopathological section. IL-10 and TGF-β1 gene expression were detected by qPCR. The measurement data with normal distribution were expressed as ( Mean± SD). Analysis of variance was used to compare the measurement data of multiple groups. T test was used to compare the measurement data between the two groups. Results:The diameter of anastomotic stoma gradually narrowed with time after choledochojejunostomy, which was(2.7± 0.3) mm at the 4st week after operation; However, liver function and inflammation index reached the peak at the 2st week after operation, and then gradually returned to normal level; The proportion of B10 cells in peripheral blood did not change significantly in each period after operation, but the infiltration of B10 cells in anastomotic tissue increased significantly, which was significantly higher than that in the control group at the first week after operation [(16.6±4.0)% vs (1.1±0.3)%, P<0.05], and it was still higher than that of the control group at the 4st week after operation [(7.5±1.3)% vs (1.1±0.3)%, P<0.05]; The pathological staining of anastomotic tissue showed that with the passage of time, the infiltration of inflammatory cells in the bile duct wall increased, the proliferation of collagen fibers, the thickening of bile duct wall, and then led to scar formation; Expression of IL-10 and TGF-1β in anastomotic tissue after operation. At the 4st week after operation, IL-10 gene expression was still higher than that of the control group [(1.4±0.6) vs (0.5±0.2), P<0.05], the gene expression of TGF-1β was increased continuously and was higher than that of the control group [(3.9±0.9) vs (0.3±0.2), P<0.05]. Conclusion:The content of B10 cells in the anastomotic tissue of rats after choledochojejunostomy is significantly increased, and the expression of IL-10 gene is high, which may play a role in regulating local scar formation.