慢性阻塞性肺病患者α1-抗胰蛋白酶的研究

目的探讨慢性阻塞性肺疾病(COPD)患者α1抗胰蛋白酶(α1AT)基因单核苷酸多态性和相应血清蛋白质水平的变化及其意义。方法采用PCR特异性等位基因扩增法检测132例COPD患者及110例疾病对照组DNAα1AT的单核苷酸多态性,采用酶联免疫吸附试验法(ELISA)测定两组的血清α1AT含量。结果S突变的PCR产物是285bp的DNA片段,Z突变的PCR产物是250bp的DNA片段。均未检测到α1AT的PiZ和PiS基因型。血清α1AT含量为COPD疾病组2.3g/L±1.1g/L,对照组2.7g/L±0.8g/L。疾病组血清α1AT含量明显低于对照组(P=0.012)。RV/TLC和喘息严重程度与α1AT血清水平明显负相关,r值分别为-0.208和-0.262。结论COPD患者α1AT的PiZ和PiS两位点的单核苷酸多态性无特异变化,α1AT的降低可能与慢性阻塞性肺疾病中肺气肿的发生有关。

The investigation of genotype and expression of alpha1-AT in patients with COPD

OBJECTIVE: To detect genotype and expression of alpha1-AT in the patients with COPD to investigate the effect of alpha1-AT on pathogenesis of COPD. METHODS: Detection of PiZ allele in exon V and S allele in exon III were performed by PCR-Amplification of Specific Allele (PASA). The levels of serum alpha1-AT in some of subjects were measured by Enzyme-Linked Immunoadsordent Assay (ELISA). RESULTS: The PCR production of S mutation was 285 base pair fragment. The PCR production of Z-mutation was 250 base pair fragment. The results showed that All subjects were PiMM genotype of alpha1-AT, including COPD and control group. The mean serum alpha1-AT concentration, in patients with COPD, was 2.3 g/L +/- 1.1 g/L. In control group, the mean serum alpha1-AT concentration was 2.7 g/L +/- 0.84 g/L. The levels of alpha1-AT in patients with COPD are significantly lower than that in control group (P = 0.012). RV/TL and degree of pursiness are negative correlation with the levels of alpha1-AT. The r value were -0.208 and -0.262 respectively. CONCLUSION: There was no difference in genetic polymorphism of alpha1-AT between the patients with COPD and controls. However, the levels of serum alpha1-AT were significantly lower in the patients with COPD compared with control subjects. alpha1-AT deficiency may be a factor of the pathogenesis of COPD. The mechanism of alpha1-AT deficiency needs to be addressed.