人血浆抗金属硫蛋白抗体与镉致肾损伤易感性的关系

目的研究人血浆抗金属硫蛋白扰体（anit-MT Ab）与职业镉接触所致肾功能损伤的关系。方法选择某镉冶炼厂男性作业工人为研究对象，进行接触评定和效应评定，以尿镉（UCd）、血镉（BCd）和职业镉摄入（TTCd）为接触指标，尿β2-微球蛋白（Uβ2-MG）、尿N-乙酰-β-D-氨基葡萄糖苷酶（UNAG）、尿白蛋白（UALB）作为镉敛肾损伤的效应标志物。酶联免疫吸附法（EHSA）检测血浆中anti-MT Ab滴度。结果职业镉接触组中UCd（3．16μg／g Cr）、血镉（9．28βg/L）、Uβ2-MC（81．17βg/g Cr）、UALB（7．03mg／gCr）水平明显高于对照组，随着职业镉接触水平升高，Uβ2-MG、UNAG和UALB含帚和异常发生率明显升高。对照组与接触组间anti-MT Ab滴度的差异无统计学意义（P〉0．05）。anti-MT Ab滴度并不随接触剂晕增加而增加，与血镉、UCd和TIEd间无明显联系（P〉0．05）。拄接触组中anti-MT Ab与UNAG和Uβ2-MG呈正相关，相关系数分别为0．302和0．218（P〈0．05）。相同机体镉负荷下，anti-MT Ab高滴度人群较低滴度人群更易出现肾小管损伤，比值比为4．200。结论职业性镉接触与肾功能损害间存在剂量一反应关系，而与血浆anti-MT Ab间无明显关联。镉接触人群中血浆anti-MT Ab高水平者更容易出现肾脏损伤。

Relationship between plasma anti-metallothionein antibody and renal dysfunction in cadmium exposed workers

OBJECTIVE: To investigate whether renal dysfunction induced by cadmium is related to plasma anti-metallothionein antibody (anti-MT Ab) in workers occupationally exposed to cadmium. METHODS: The male workers in a smeltery were selected as the subjects for the exposure and effect assessment. The urine cadmium (UCd), the blood cadmium (BCd) and the occupational cadmium intake (TTCd) served as the exposure indexes while the urine beta(2) microglobulin (Ubeta(2)-MG), the N-acetyl-beta-D-glucosaminidase (UNAG) and the urine albumin concentration (UALB) served as the effect markers for the renal dysfunction caused by the cadmium. The titer of the plasma anti-metallothionein antibody was determined with the enzyme linked immunosorbent assay (ELISA). RESULTS: The UCd (3.16 microg/g Cr), BCd (9.28 microg/L), Ubeta(2)-MG (81.17 microg/g Cr) and UALB (7.03 mg/g Cr) in the occupational cadmium exposure group were significantly higher than those in the control group and the Ubeta(2)-MG, UNAG and UALB as well as the occurrence rate of abnormality would be increased with the increase of the level of the occupational cadmium exposure. There was no significant difference in the titer of anti-MT Ab between the exposure group and the control group (P > 0.05). The titer of the anti-MT Ab would not be increased with the increase of the dosage of the exposure and had no significant correlation with BCd, UCd and TTCd (P > 0.05). The positive correlation were found between anti-MT Ab and UNAG as well as between anti-MT Ab and Ubeta(2)-MG in the exposure group with the correlation coefficient of 0.302 and 0.218 respectively. The workers with high level anti-MT Ab are more susceptible to cadmium nephrotoxicity than those with low anti-MT Ab with the odds ratio (OR) value of 4.200 and the 95% CI between 1.213 and 14.541 (P < 0.05). CONCLUSION: There is a dose-effect relationship between cadmium exposure and renal dysfunction in workers occupationally exposed to cadmium, but no correlation is found between cadmium exposure and plasma anti-MT Ab. The workers occupationally exposed to the cadmium with higher level of anti-MT Ab are easier to suffer from renal dysfunction caused by cadmium. Plasma anti-MT Ab could be used as a biomarker of susceptibility in the workers exposed to cadmium.