Study on proteomics of the serum biomarker from children with ITP

LIU Chun-yan; CHEN Hong-ying; LIU Wen-jun

Abstract：Objective To screen for the serum protein marker used in the early diagnosis, typing, monitoring and pre-diction of prognosis of idiopathic thrombocytopenic purpura (ITP), and to eatablish ITP diagnostic model, verifying the new way of molecular diagnosis of ITP at the serum protein level. Methods SELDI-TOF-MS was applied to test the se-rum protein combined with the protein chip. Twenty-five cases of acute ITP, 10 cases of chronic ITP, and 25 finger prints of serum protein from the control group were collected. Biomarker Wizard and the software of Biomarker Patterns System 5.0 were applied to analyze the data and a diagnostic model was established. Results Within the range of mass electron ration (m/e) of 2000-20000, when a contrast was made between the ITP group and the control group, 31 pro-tein peaks were statistically significant (P < 0.01), 6 peaks of which were of high expression and 25 low expression. The most significant protein was that with the M/E of 4121.27 5327.56 5890.56, which could be recognized as serum bio-marker for ITP. Nine protein peaks were found statistically significant (P < 0.01) between the ITP group and the control group, 7 of which were of high expression and 2 low expression. The most significant protein was that with the M/E of 3930.39 6097.56, which could be recognized as serum biomarker for chronic ITP. By integrating respective serum bio-marker from the two types of protein into the diagnostic model of artificial neural network, the ITP group and the control group could be divided accurately with the sensitivity of 100%, specificity of 100%, and the integration's sensi-tivity to the diagnostic model of acute and chronic ITP was 92.9%, specificity 83.3%. Conclusions 1) There is a significant difference between the levels of serum protein from the ITP group and those from normal children. 2) There is a significant difference between the levels of serum pro-tein from the group of acute ITP and those from chronic ITP group. 3 )The diagnostic model of protein combination, with M/E of 4121.27 5327.56 5890.56, can completely and accurately distinguish the ITP group and the control group of normal children, therefore this kind of protein might be the serum biomarker for ITP. 4) The diagnostic model of protein combination, with M/E of 3930.39 6097.56, can accurately type the ITP group. The discrepant protein supplied is help-ful to learn about the molecule mechanism of the different features between acute and chronic ITP, thus possibility for targeted therapy is provided and the abovementioned protein might be the serum biomarker for chronic ITP. 5) SE-LI-TOF-MS technology is an effective tool to seek disease-related proteins.