溃疡性结肠炎中B细胞对巨噬细胞趋化作用的初步研究

Pilot study on the mechanism of B cell chemotaxis of macrophage in ulcerative colitis

目的观察B细胞与巨噬细胞在溃疡性结肠炎疾病进展过程中在结肠组织中的浸润比例变化,探讨两种细胞间趋化作用机制。方法使用经典氧化偶氮甲烷/葡聚糖硫酸钠(azoxy-methane/dextran sodium sulfate,AOM/DSS)小鼠溃疡性结肠炎癌变模型作为研究对象,分别获取不同疾病阶段小鼠外周血及结肠组织,利用流式细胞法检测免疫细胞比例,利用real-time PCR法及免疫荧光法检测趋化因子单核细胞趋化蛋白-1(monocyte chemoattractant protein-1,MCP1/CCL2)。结果随着溃疡性结肠炎相关结肠癌小鼠疾病进展,结直肠组织中B细胞和巨噬细胞的浸润比例逐渐增加,而当B细胞缺乏时,巨噬细胞的浸润会明显减少。B细胞是巨噬细胞的趋化因子CCL2的重要来源之一。结论在溃疡性结肠炎疾病进展过程中,B细胞可通过上调表达CCL2趋化巨噬细胞至结直肠组织。

Objective To study the infiltration ratio of B cell and macrophage in the colon tissue during the progression of ulcerative colitis and explore the mechanism of chemotaxis between the two cells.Methods With the classic AOM/DSS mouse ulcerative colitis carcinogenesis model as the research object,the peripheral blood and colon tissues of mice at different disease stages were obtained.The proportion of immune cells was detected by flow cytometry,and the real-time PCR method and immunofluorescence method were used to detect chemokine monocyte chemoattractant protein-1(MCP1/CCL2).Results The proportion of B cell and macrophage infiltration in colorectal tissues increased with the progress of ulcerative colitis-related colon cancer in mice.The infiltration of macrophages was significantly reduced if there was a lack of B cells.Further research found that B cell was one of the important sources of the chemokine CCL2 of macrophages.Conclusion During the progression of ulcerative colitis,B cells could chemoattract macrophages to colorectal tissues by up-regulating the expression of CCL2.