Serum proteomic profiling analysis of chronic arsenic exposure by using SELDI-TOF-MS technology

This study was to investigate the differences in serum proteomic profiling among subjects exposed to different levels of arsenic in drinking water and to identify proteins related to arsenicosis. A total of 148 subjects from endemic regions of China were selected and divided into low (0-8.30 microg/L), medium (16.30-37.60 microg/L) and high (140.88-273.67 microg/L) exposure groups. High exposure group consisted of subjects with and without skin lesions. Serum proteomic profiling was analyzed by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) technology. Twenty proteins were found significantly different among three groups. Further multivariate logistic regression revealed that no different proteins existed in medium versus low exposure group. A panel of five proteins, including m/z of 15167.7, 7783.1, 7580.7, 2952.6 and 2237.4, was seen in high versus low exposure group, with a sensitivity of 93.0% and specificity of 87.5%. The same panel was found in high versus a combination of low and medium exposure groups but with somewhat lower predicting power. Only one protein was significantly different between high exposure group with and without skin lesions. The results indicate that high levels of arsenic exposure could significantly change human serum proteomic profiling, which can be detected before skin lesions occur.