Biological effects of chlamydiaphage phiCPG1 capsid protein Vp1 on chlamydia trachomatis in vitro and in vivo

Abstract

The researches on chlamydia in recent years show that chlamydia bacteriophage may be a potential and effective means to solve the clinical infection of chlamydia trachomatis (Ct). We investigated the biological effect of chlamydiaphage phiCPG1 capsid protein Vp1 on Ct both in McCoy cells and genital tract of mice. Different concentrations of Vp1 were co-incubated with Ct E serotype strain in McCoy cells. Female BALB/c mice were used to establish Ct E strain-induced urogenital infection model. They were randomly divided into five groups and given different treatments on the fifth day after Ct inoculation. Animals in groups 1 and 2 were given 30 μL different concentrations of Vp1 in the genital tract respectively, those in group 3 were intramuscularly injected with 30 μL Vp1, those in the infected group did not receive any intervention, and those in the control group received 30 μL PBS in the genital tract. The vaginal discharge was collected to identify the live chlamydia by cell culture and gene fragment by real time PCR different days after infection. Inhibition rate of 100 μg/mL and 50 μg/mL Vp1 proteins against Ct E strain in the McCoy cell cultures was 91% and 79% respectively. The number of intracellular Ct inclusion in the McCoy cells co-cultured with vaginal discharge of group 1 and group 2 was less than in the infected group, and that in group 1 was less than in group 2, on the 7th day after Ct inoculation. Real-time PCR showed that chlamydia concentration of the vaginal discharge in group 2 was lower than in the infected group, and that in group 1 was lower than in group 2 on the 10th day. It was suggested that Vp1 capsid proteins had inhibitory effect on the proliferation of Ct serovar E strain in cell culture and mouse genital tract.

Keywords

chlamydia trachomatis / trachoma / mice / phage / Vp1 protein

References

[1] LiuYJ, ShengCH, LiuY, et al. . Preparation, identification and application of polyclonal antibody against major outer membrane protein of Chlamydia trachomatis E. Chin J Infect Dis (Chinese), 2011, 29(5): 257-260

[2] KongFYS, HockingJS. Treatment challenges for urogenital and anorectal Chlamydia trachomatis. BMC Infect Dis, 2015, 15(1): 1-7

[3] HouSP, LiuYJ, MaJY, et al. . Preparation and preliminary application of monoclonal antibody against Vp1 protein of chlamydiaphage FCPG1. Chin J Dermat (Chinese), 2010, 43(5): 320-323

[4] MaJY, LiuQZ, LiuYJ, et al. . Detection of Chlamydia trachomatis phage capsid protein Vp1 antibody. Chin J Dermat (Chinese), 2009, 42(5): 360-362

[5] HsiaRC, OhayonH, GounonP, et al. . Phage infection of the obligate intracellular bacterium, chlamydia psittaci strain guinea pig inclusion conjunctivitis. Microbes Infect, 2000, 2(7): 761-772 PMID: 10955956

[6] IllyaT, ChristelleEH, CarabeoRA. Human guanylate binding proteins potentiate the anti-chlamydia effects of interferon-gamma. Plos One, 2012, 4(8): e6499-e6499

[7] LiuYJ, HouSP, WeiJR, et al. . The effect of chlamydiaphage phiCPG1 capsid protein Vp1 on the Chlamydia trachomatis. Chin J Microbiol Immunol (Chinese), 2012, 32(5): 403-407

[8] SandozKM. Antibiotic resistance in Chlamydiae. Future Microbiol, 2010, 5(9): 1427-1442 PMID: 20860486 PMCID: 3075073

[9] ZengH, GongSQ, HouSP, et al. . Identification of antigen-specific antibody responses associated with upper genital tract pathology in mice infected with Chlamydia muridarum. Infect Immun, 2011, 80(3): 1098-1106 PMID: 22158739

[10] SalimO, SkiltonRJ, LambdenPR, et al. . Behind the chlamydial cloak: the replication cycle of chlamydiaphage Chp2, revealed. Virology, 2008, 377(377): 440-445 PMID: 18570973

[11] ReadTD, BrunhamRC, ShenC, et al. . Genome sequences of Chlamydia trachomatis MoPn and Chlamydia pneumoniae AR39. Nucleic Acids Res, 2000, 28(6): 1397-1406 PMID: 10684935 PMCID: 111046

[12] EversonJS, GarnerSA, LambdenPR, et al. . Host range of chlamydiaphages phiCPAR39 and Chp3. J Bacteriol, 2003, 185(21): 6490-6492 PMID: 14563888 PMCID: 219413

[13] LaszloK, WhitmireWM, CarlsonJH, et al. . Pathogenic diversity among Chlamydia trachomatis ocular strains in nonhuman primates is affected by subtle genomic variations. J Infect Dis, 2008, 197(3): 449-456

[14] MeijerA, MorréSA, BruleAJ, et al. . Genomic relatedness of Chlamydia isolates determined by amplified fragment length polymorphism analysis. J Bacteriol, 1999, 181(15): 4469-4475 PMID: 10419941 PMCID: 103574

[15] MorréSA, LyonsJM, ItoJI. Murine models of Chlamydia trachomatis genital tract infection: use of mouse pneumonitis strain versus human strains. Infect Immun, 2000, 68(12): 7209-7211 PMID: 11203323 PMCID: 97843

[16] YangB, ZhengHP, FengZQ, et al. . The prevalence and distribution of Chlamydia trachomatis genotypes among sexually transmitted disease clinic patients in Guangzhou, China, 2005-2008. Jpn J Infect Dis, 2010, 63(5): 342-345 PMID: 20859001