PbGPI16在C57BL/6小鼠脑疟发病过程中作用的研究

Function of PbGPI16 in cerebral malaria pathology of Pb. ANKA infected C57BL/6 mice

目的:PbANKA原虫PbGPI16在小鼠实验性脑疟(ECM)发生和发展过程中的作用。方法:采用pbgpi16基因敲除的PbANKA原虫(△pbgpi16)和PbANKA原虫(WT)感染C57BL/6小鼠建立ECM模型。动态监测原虫血症和生存期;HE染色检测ECM小鼠脑组织炎性细胞浸润。q PCR观察感染后小鼠脑组织中CXCL9、CXCL10和CXCR3及脾细胞中TNF-α、IFN-γ和IL-1β转录水平。ELISA检测血清和脾细胞培养上清中TNF-α、IFN-γ和IL-1β表达水平。FACS检测感染后小鼠脾脏DCs细胞MHCⅡ和TLR4表达水平。结果:与WT组相比,△pbgpi16感染C57BL/6小鼠脑微血管壁损伤减轻,CXCL9、CXCL10、CXCR3、TNF-α、IFN-γ和IL-1β转录水平,小鼠血清和脾细胞培养上清中TNF-α、IFN-γ和IL-1β表达水平和脾DCs表达MHCⅡ及TLR4数量均显著下降(P<0. 05)。结论:PbGPI16缺失通过减轻小鼠脑组织中趋化因子和脾脏中前炎症细胞因子转录水平,降低血清和脾细胞中前炎症细胞因子表达水平,降低DCs活化水平而抑制ECM发生。本研究旨在为疟疾感染后脑疟病理研究提供理论基础。

Objective:To investigate the function of PbGPI16 protein in murine experimental cerebral malaria(ECM)pathology.Methods:Establishment of ECM model by C57BL/6 mice infected with Pb.ANKA wild type(WT)and pbgpi16 gene knockout(△pbgpi16)strain,respectively.Dynamic monitoring parasitemia and survival;the microvessel injury in ECM developed mice was detected by HE staining.qPCR was used to observe the CXCL9,CXCL10 and CXCR3 levels in the brain and TNF-α,IFN-γand IL-1βlevels in the spleen cells at different time points after infection.ELISA assay was used to check the expression levels of TNF-α,IFN-γand IL-1βin serum and spleen cells.FACS was used to detect the expression level of DCs activating molecules(MHCⅡand TLR4)in the spleen of infected mice.Results:The injury of C57BL/6 microvessel in C57BL/6 mice infected with△pbgpi16 was alleviated,and the transcription level of CXCL9,CXCL10,CXCR3,TNF-α,IFN-γand IL-1βdecreased significantly(P<0.05).The expression levels of TNF-α,IFN-γand IL-1βin spleen and serum of△pbgpi16 infected mice decreased significantly(P<0.05).Furthermore,in△pbgpi16 infected mice,the expression level of MHCⅡand TLR4 in spleen DCs decreased significantly(P<0.05).Conclusion:The deletion of PbGPI16 protein inhibits the occurrence of ECM by reducing the transcription level of chemokines and pro-inflammatory cytokines in the brain and spleen.Meanwhile,the expression levels of pro-inflammatory cytokines also reduced,and the level of DCs activation in the spleen was inhibited.The aim of this study is to provide a theoretical basis for pathological studies of malaria infection.