Department of Respiratory Medicine, Guizhou Provincial People's Hospital, Guiyang, Guizhou, China.
Department of Respiratory Medicine, The First People's Hospital of Liangshan Yi Autonomous Prefecture, Xichang, Sichuan, China.
COPD. 2022 May 4;19(1):255-261. doi: 10.1080/15412555.2022.2072720.
Our previous study suggested that hypomethylation of perforin promoter of CD4 + T cells might be involved in the pathogenesis of autoimmune emphysema of rats. Whether transfer of this kind of cells hypomethylated into naive immunocompetent rats also results in emphysema is unknown yet. To test the hypothesis above, thirty Sprague Dawley (SD) rats were randomly divided into three groups: a model group ( = 10), a normal control group ( = 10) and a sham operation group ( = 10). In the model group, spleen-derived CD4 + T cells of normal rats were treated with 5-azacytidine (5-Aza), complete Freund's adjuvant and Phosphate Buffered Saline (PBS), then transferred into naive immunocompetent rats. The normal control group was injected with CD4 + T lymphocytes from spleens of normal rats and the same amount of adjuvant and PBS as above. In sham operation group, normal rats were injected intraperitoneally with complete Freund's adjuvant and PBS. Histopathological evaluations (mean linear Intercept (MLI) and mean alveolar numbers (MAN)), anti-endothelial cell antibodies (AECA) in serum and bronchoalveolar lavage fluid (BALF), lung vascular endothelial growth factor (VEGF)), the apoptotic index (AI) of alveolar septal cells and the methylation levels of perforin promoter of CD4 + T cells were investigated. The levels of the methylation above and MAN were lower in the model group than in the control and the sham operation group, while the AECA in serum and BALF, VEGF, MLI and the AI were greater (all < 0.05). The methylation levels of perforin promoter were positively correlated with the MAN ( = 0.747, < 0.05) and negatively correlated with AI, AECA, MLI, and VEGF ( was -0.789, -0.746, -0.743, -0.660, respectively, all < 0.05). This study suggests that transfer of invitro CD4 + T cells with hypomethylation of perforin promoter into rats causes autoimmune emphysema, possibly by increasing expression of VEGF and promoting alveolar septal cell apoptosis.
我们之前的研究表明，CD4+T 细胞穿孔素启动子的低甲基化可能与大鼠自身免疫性肺气肿的发病机制有关。但是否将这种低甲基化的细胞转移到未致敏的免疫功能正常的大鼠体内也会导致肺气肿尚不清楚。为了验证上述假说，将 30 只 SD 大鼠随机分为三组：模型组（n=10）、正常对照组（n=10）和假手术组（n=10）。在模型组中，用 5-氮杂胞苷（5-Aza）、完全弗氏佐剂和磷酸盐缓冲液（PBS）处理正常大鼠的脾源性 CD4+T 细胞，然后将其转移至未致敏的免疫功能正常的大鼠体内。正常对照组注射来自正常大鼠脾的 CD4+T 淋巴细胞，并给予相同量的佐剂和 PBS。在假手术组中，正常大鼠腹腔内注射完全弗氏佐剂和 PBS。观察各组大鼠的组织病理学改变（平均线性截距（MLI）和平均肺泡数（MAN））、血清和支气管肺泡灌洗液（BALF）中的抗内皮细胞抗体（AECA）、肺血管内皮生长因子（VEGF））、肺泡间隔细胞的凋亡指数（AI）和 CD4+T 细胞穿孔素启动子的甲基化水平。结果发现，模型组的上述甲基化水平和 MAN 低于对照组和假手术组，而血清和 BALF 中的 AECA、VEGF、MLI 和 AI 则较高（均 P<0.05）。CD4+T 细胞穿孔素启动子的甲基化水平与 MAN 呈正相关（r=0.747，P<0.05），与 AI、AECA、MLI 和 VEGF 呈负相关（r=-0.789、-0.746、-0.743、-0.660，均 P<0.05）。本研究提示，体外 CD4+T 细胞穿孔素启动子低甲基化转移至大鼠体内可导致自身免疫性肺气肿，可能通过增加 VEGF 的表达和促进肺泡间隔细胞凋亡来实现。
