Preparation and preliminary application of monoclonal antibody against Vp1 protein of chlamydiaphage ΦCPG1

Objective To express recombinant Vp1 protein of chlamydiaphage φCPG1, prepare monoclonal antibody against Vp1 protein and utilize it to screen clinical isolates of Chlamydia trachomatis. Methods The Vp1 protein was obtained by prokaryotic expression, and monoclonal antibody against this protein was prepared by hybridoma technique. ELISA and Western blot were used to identify monoclonal antibodies. Then,the monoclonal antibody was prepared in quantity by injecting hybridoma cells into the abdominal cavity of BALB/C mice, and purified by using protein G affinity chromatography. Clinical isolates of Chlamydia trachomatis were screened for the chlamydiaphage by immumofluorescence assay using the prepared monoclonal antibody.Results Purified Vp1 protein was obtained. The monoclonal antibody against Vp1 protein was gained after 3times of sub-clone and consistently identified as IgG1. Three hybridoma cell strains that stably secreted monoclonal antibody were generated. Chromosome analysis of hybridoma cells showed that the mean number of chromosome was 96, most of them were telocentric and a few were submetacentric. The titer of purified monoclonal antibody was more than 1: 12 800. Twenty clinical isolates were screened by using the monoclonal antibody and no positive results were obtained. Conclusions The monoclonal antibody against Vp1 protein of chlamydiaphage φCPG1 is successfully prepared, while no chlamydiaphage is detected by immumofluorescence assay using the prepared antibody in 20 clinical isolates of Ct. Key words: Chlamydiaphages;  Capsid proteins;  Antibodies, monoclonal;  Chlamydia trachomatis