[Mycoplasma infection and cancer].

Mycoplasmas are widespread in nature as conditional pathogen, which may be the unique prokaryote that can cohabit with eukaryote and interact permanently with mammalian cells. Mycoplasma infection can be detected in many tumor tissues, continuous infection of mycoplasma can lead to transformation of mammalian cells, up-regulating expression of oncogenes, and some biologic changes of tumor cells, suggesting association of mycoplasma infection with tumorigenesis.

Identification of antigens by monoclonal antibody PD4 and its expression in Escherichia coli.

Aim: To clone and express the antigen of monoclonal antibody (MAb) PD4 for further investigation of its function.

Methods: MGC803 cDNA expression library was constructed and screened with PD4 as probes to clone the antigen. After failed in the library screening, immunoprecipitation and SDS-polyacrylamide gel electrophoresis were applied to purify the antigen for sequence analysis.