Anti-HSPD1 monoclonal antibody, clone Nbc22-24

Over the past few years, there has been a growing interest in discovering the molecular mechanisms controlling embryonic stem cells' (ESCs) proliferation and differentiation. Proteome analysis has proven to be an effective approach to comprehensively unravel the regulatory network of differentiation. We applied a two-dimensional electrophoresis based proteomic approach followed by mass spectrometry to analyze the proteome of two mouse ESC lines, Royan B1 and D3, at 0, 6, and 16 days after differentiation initiation. Out of 97 ESC-associated proteins commonly expressed in two ESC lines, 72 proteins were identified using MALDI TOF-TOF mass spectrometry analysis. The expression pattern of four down-regulated proteins including Hspd1, Hspa8, beta-Actin, and Tpt1 were further confirmed by Western blot and immunofluorescence analyses in Royan B1 and D3 as well as two other mouse ESC lines Royan C1 and Royan C4. Differential mRNA expression analysis of 20 genes using quantitative real-time reverse transcription PCR revealed a low correlation between mRNA and protein levels during differentiation. We also observed that the mRNA level of Tpt1 increased significantly in differentiating cells, whereas its protein level decreased. Several novel ESC-associated proteins have been presented in this study which warrants further investigation with respect to the etiology of sternness.

The present study aimed to select anti-tumor-associated antigen (TAA) autoantibodies as biomarkers in the immunodiagnosis of gastric adenocarcinoma (GAC) by the recursive partitioning approach (RPA) and further construct and evaluate a predictive model. A case-control study was designed including 407 GAC patients as the case group and 407 normal controls. In addition, 67 serial serum samples from 25 GAC patients were collected at different time points before and after gastrectomy treatment. Autoantibodies against 14 TAA were measured in sera from all subjects by enzyme immunoassay. Finally, RPA resulted in the selection of nine-panel TAA (c-Myc, p16, HSPD1, PTEN, p53, NPM1, ENO1, p62, HCC1.4) from all detected TAA in the case-control study; the classification tree based on this nine-TAA panel had area under curve (AUC) of 0.857, sensitivity of 71.5% and specificity of 71.3%; The optimal panel also can identify GAC patients at an early stage from normal individuals, with AUC of 0.737, sensitivity of 64.9% and specificity of 70.5%. However, frequencies of the nine autoantibodies showed no correlation with GAC stage, tumor size, lymphatic metastasis or differentiation. GAC patients positive for more than two autoantibodies in the nine-TAA panel had a worse prognosis than that of the GAC patients positive for no or one antibody. Titers of 10 autoantibodies in serial serum samples were significantly higher in GAC patients after surgical resection than before. In conclusion, this study showed that the panel of nine multiple TAAs could enhance the detection of anti-TAA antibodies in GAC, and may be potential prognostic biomarkers in GAC.