树突状细胞对胃粘膜免疫的调节作用研究

Effects of dendritic cells on gastric mucosal immunity in human beings

目的 通过研究胃粘膜中S 10 0 +,HLA DR+,CD4 +和CD8+产物的表达情况 ,以了解树突状细胞 (DC)在胃粘膜免疫中的作用。方法 胃癌 ( 176例 )、慢性萎缩性胃炎 ( 4 1例 )、不典型增生 ( 15例 )、肠上皮化生 ( 2 7例 )和正常对照组 ( 10例 )共 2 69例 ,采用HE染色、S P免疫酶标抗体组化染色法与图像分析技术相结合 ,观察胃粘膜中S 10 0 +,HLA DR+,CD4 +和CD8+细胞数量、平均面积和平均吸光度的变化。结果 胃癌患者胃粘膜中S 10 0 +,HLA DR+细胞数量明显多于正常胃粘膜 (P <0 .0 5) ;CD4 +细胞及其平均吸光度显著减少 (P <0 .0 1) ;CD8+细胞数量、面积及其平均吸光度略有减少 ,但与正常组比较差异不显著 (P >0 .0 5) ;CD4 + CD8+比值为 0 .65,显著低于正常胃粘膜 (P <0 .0 1)。慢性萎缩性胃炎、肠上皮化生和不典型增生胃粘膜中S 10 0 +、HLA DR+细胞数量显著增加 (P <0 .0 1) ;CD8+细胞数量均明显高于正常胃粘膜 (P <0 .0 5) ;CD4 + CD8+比值分别为 0 .81,0 .59,0 .56,均显著低于正常胃粘膜 (P <0 .0 5)。结论 癌前状态胃粘膜中DC数量显著增多 ,功能增强 ;而胃癌患者胃粘膜中DC数量随分化程度的降低而减少。胃粘膜中DC细胞功能的抑制是导致胃粘膜免疫功能低下和癌前状态发生癌变的重要原因之一。

Objective To investigate the effect of dendritic cell (DC) on gastric mucosal immunity from expressions of S 100,HLA DR,CD4 and CD8 in human gastric mucosa. Methods A total of 269 patients suffering from gastric cancer (GC, n =176),chronic atrophic gastritis (CAG, n =41),dysplasia (Dys, n =15) and intestinal metaplasia (IM, n =27), and 10 normal subjects were studied. The diagnosis of all the cases was verified with endoscopy and/or histopatholgical examination. The number, mean area and absorbance of S 100 +,HLA DR +,CD4 + and CD8 + cells were detected with HE and immunohistochemical (S P method) staining and image analysis. Results The number of S 100 + and HLA DR + cells in gastric mucosa was significantly higher in patients with GC, CAG, Dys and IM than in normal control (0.6±0.2/μm 2 and 0.9±0.2/μm 2 , 1.8±0.3/μm 2 and 2.4±0.6/μm 2, 2.2±0.5/μm 2 and 2.8±0.6/μm 2, 2.2±0.6/μm 2 and 3.0±0.8/μm 2 ,0.2±0.1/μm 2 and 0.5±0.1/μm 2, respectively, P <0.05). The number of CD4 + cells and the mean absorbance were markedly lower in GC (0.7 ± 0.2 /μm 2) than in normal control (2.3±0.4/μm 2) ( P <0.01). The number of CD8 + cells and their mean area and absorbance showed no obvious difference between GC and normal ( P >0.05),but the number of CD8 + cells was higher in CAG, Dys and IM than in normal, (1.8±0.2/μm 2,1.8± 0.2/μm 2 ,1.9±0.2/μm 2 and 1.2±0.1/μm 2 respectively, P <0.05). The ratio of CD4/CD8 was lower in GC (0.65), CAG(0.81), IM(0.59), Dys(0.56) than in normal (1.94)( P <0.05).Conclusion The number of DC in gastric mucosa of precancerous lesions is increased and its function is enhanced, but they are positively correlated to the degree of differentiation in gastric cancer. Inhibited function of DC in gastric mucosa is one of important factors that lead to the decrease of gastric mucosa and the precancerous lesions to change into cancer.