Monoclonal Antibodies Against Human Bit1,An Apoptosis-Associated Mitochondrial Protein

Abstract

Bit1 (Bcl2-inhibitor of transcription 1) is a mitochondrial protein that was found eliciting caspase-independent apoptosis when released into the cytoplasm, where it forms a complex with AES (amino-terminal enhancer of split). In our research, cytosolic fraction of suspended cultured human ovarian cancer cells was taken as immunogen, and recombined protein Bit1-His was used to select hybridomas. Two hybridoma cell lines secreting monoclonal antibodies (MAbs) against Bit1 were obtained by routine murine hybridoma technique. The MAbs were characterized by indirect ELISA, Western blotting, and immunohistochemistry, and it was found that they recognized distinct epitopes. The sandwich method to detect sera Bit1 was established, and a distinct difference of sera Bit1 between the ovarian carcinoma patients and normal controls was found. To conclude, these MAbs against human Bit1 may be useful for exploring the tumor apoptosis mechanism and monitoring patients' clinical data.