AIM： To investigate the effect of IL-4 on the altered expression of complement activation regulators in pancreas and pancreatic necrosis during experimental severe acute pancreatitis （SAP）. METHODS： SAP model of r...AIM： To investigate the effect of IL-4 on the altered expression of complement activation regulators in pancreas and pancreatic necrosis during experimental severe acute pancreatitis （SAP）. METHODS： SAP model of rats was established by retrograde injection of 5% sodium taurocholate （1 mL/kg） into the pancreatic duct. We immunohistochemically assayed the expression of three complement activation regulators： decay accelerating factor （DAF; CD55）, 20 ku homologous restriction factor （HRF20; CD59） and membrane cofactor protein （MCP; CEH6）, in the pancreatic acinar cells of rats at 0, 3, 6, 12, and 24 h after the induction of SAP model. Meanwhile the levels of amylase and lipase were determined, and morphological examination was performed. Then, 61 rats were randomly divided into three groups. Group A （n = 21） received no treatment after the SAP model was established; group B （n = 20） was given IL-4 （8 IJg/animal） intraperitoneally 0.5 h before the SAP model was established; group C （n = 20） was given IL-4 （8 μg/animal） intraperitoneaUy 0.5 h after the SAP model was established. Plasma amylase and lipase, extent of pancreatic necrosis and expression of complement activation regulators were investigated 6 h after the induction of SAP model. RESULTS： Three complement activation regulators were all expressed in pancreatic acinar cells. MCP was not found on the basolateral surface as reported. Contrary to the gradually increasing plasma level of amylase and lipase, expression of complement activation regulators decreased after SAP model was set up. At the same time, the severity of pancreatic necrosis was enhanced. A strong negative correlation was found between the expression of MCP, DAF, CD59 in pancreatic acinar cells and the severity of pancreatic necrosis （r = -0.748, -0.827, -0.723; P〈0.01）. In the second series of experiments, no matter when the treatment of IL-4 was given （before or after the induction of SAP model）, the serum level of amylase or lipase was decreased and the extent of pancreatic necrosis was ameliorated significantly. Compared to SAP control group, the expression of DAF and CD59 in pancreas was reinforced when IL-4 was given before the induction of SAP model （P〈0.01, P〈0.05）, but the expression of MCP was not influenced （P〉0.05）. The expression of DAF was enhanced, when IL-4 was given after the induction of SAP model （P〈0.05）, but the expression of CD59 and MCP did not change （P〉0.05）. CONCLUSION： Complement activation regulators may participate in the pathogenesis of pancreatic inflammation. Downregulation of complement activation regulators expression may be one of the causes of pancreatic necrosis. IL-4 treatment may control SAP aggravation by enhancing expression of DAF and CD59 in pancreas and decreasing pancreatic necrosis. Moreover, DAF and CD59 may play an important role in the regulation of complement activation regulators during SAP.展开更多
Thichosanthin (TCS) is a potent allergen to mice. According to our previous experiments, it could bring out the IgE response to ovabumin (OVA) if TCS was given one day before OVA immunization, while OVA alone could no...Thichosanthin (TCS) is a potent allergen to mice. According to our previous experiments, it could bring out the IgE response to ovabumin (OVA) if TCS was given one day before OVA immunization, while OVA alone could not induce IgE to it. In this work, the kinetics of interleukin 4(IL-4) and interferon γ(IFN-γ) gene expression in the mesenteric lymph node (MLN) of TCS-immunized mice was investigated using a semi-quantitative RT-PCR method. It indicated that TCS induced significant IL-4gene expression and the peaks of IL4 gene expression were on day one after TCS immunization in both primary and secondary response. In contrast, the IFN-γ gene expression was suppressed. Furthermore, the IL-4 gene expression in the secondary response was lower than that in the primary response. Thus the presence of IgE rpemory B cells were studied. Results showed that the amount of mature IgE mRNA arose significantly and rapidly one day after TCS restimulation, while in the MLN of the mice primed 30 days before and without boost, it was almost as the same amount of the unimmunized control. These findings suggest the existence of the IgE memory B cells in the mice after the primary TCS immunization.展开更多
基金Supported by the Research Program of Science and Technology Technology Commission Foundation of Liaoning Province, No. 2001225001-17
文摘AIM： To investigate the effect of IL-4 on the altered expression of complement activation regulators in pancreas and pancreatic necrosis during experimental severe acute pancreatitis （SAP）. METHODS： SAP model of rats was established by retrograde injection of 5% sodium taurocholate （1 mL/kg） into the pancreatic duct. We immunohistochemically assayed the expression of three complement activation regulators： decay accelerating factor （DAF; CD55）, 20 ku homologous restriction factor （HRF20; CD59） and membrane cofactor protein （MCP; CEH6）, in the pancreatic acinar cells of rats at 0, 3, 6, 12, and 24 h after the induction of SAP model. Meanwhile the levels of amylase and lipase were determined, and morphological examination was performed. Then, 61 rats were randomly divided into three groups. Group A （n = 21） received no treatment after the SAP model was established; group B （n = 20） was given IL-4 （8 IJg/animal） intraperitoneally 0.5 h before the SAP model was established; group C （n = 20） was given IL-4 （8 μg/animal） intraperitoneaUy 0.5 h after the SAP model was established. Plasma amylase and lipase, extent of pancreatic necrosis and expression of complement activation regulators were investigated 6 h after the induction of SAP model. RESULTS： Three complement activation regulators were all expressed in pancreatic acinar cells. MCP was not found on the basolateral surface as reported. Contrary to the gradually increasing plasma level of amylase and lipase, expression of complement activation regulators decreased after SAP model was set up. At the same time, the severity of pancreatic necrosis was enhanced. A strong negative correlation was found between the expression of MCP, DAF, CD59 in pancreatic acinar cells and the severity of pancreatic necrosis （r = -0.748, -0.827, -0.723; P〈0.01）. In the second series of experiments, no matter when the treatment of IL-4 was given （before or after the induction of SAP model）, the serum level of amylase or lipase was decreased and the extent of pancreatic necrosis was ameliorated significantly. Compared to SAP control group, the expression of DAF and CD59 in pancreas was reinforced when IL-4 was given before the induction of SAP model （P〈0.01, P〈0.05）, but the expression of MCP was not influenced （P〉0.05）. The expression of DAF was enhanced, when IL-4 was given after the induction of SAP model （P〈0.05）, but the expression of CD59 and MCP did not change （P〉0.05）. CONCLUSION： Complement activation regulators may participate in the pathogenesis of pancreatic inflammation. Downregulation of complement activation regulators expression may be one of the causes of pancreatic necrosis. IL-4 treatment may control SAP aggravation by enhancing expression of DAF and CD59 in pancreas and decreasing pancreatic necrosis. Moreover, DAF and CD59 may play an important role in the regulation of complement activation regulators during SAP.
文摘Thichosanthin (TCS) is a potent allergen to mice. According to our previous experiments, it could bring out the IgE response to ovabumin (OVA) if TCS was given one day before OVA immunization, while OVA alone could not induce IgE to it. In this work, the kinetics of interleukin 4(IL-4) and interferon γ(IFN-γ) gene expression in the mesenteric lymph node (MLN) of TCS-immunized mice was investigated using a semi-quantitative RT-PCR method. It indicated that TCS induced significant IL-4gene expression and the peaks of IL4 gene expression were on day one after TCS immunization in both primary and secondary response. In contrast, the IFN-γ gene expression was suppressed. Furthermore, the IL-4 gene expression in the secondary response was lower than that in the primary response. Thus the presence of IgE rpemory B cells were studied. Results showed that the amount of mature IgE mRNA arose significantly and rapidly one day after TCS restimulation, while in the MLN of the mice primed 30 days before and without boost, it was almost as the same amount of the unimmunized control. These findings suggest the existence of the IgE memory B cells in the mice after the primary TCS immunization.
