The Biological Effects Of Chlamydiaphage PhiCPG1 Capsid Protein Vp1 On Chlamydia Trachomatis

Chlamydia trachomatis(Chlamydia trachomatis,C.t)infection is closely related to human diseases,C.t can cause not only trachoma and inclusion conjunctivitis and pneumonia in infants but also urinary tract infection,venereal lymphogranuloma and other diseases.At present,in many countries Ct has become one of the major pathogens of sexually transmitted diseases(sexually transimitted,disease,STD).In Europe and America countries,STD caused by Ct infection has become the most common STD more than gonorrhea.The prevalence of genital Chlamydia trachomatis infections(genital Chlamydia trachomatis infections,GCI)in our country is also increasing year by year.Sexual transmission of Chlamydia trachomatis cause endometritis,female vaginitis,cervicitis,salpingitis,non gonococcal urethritis,pelvic inflammatory disease,ectopic pregnancy,spontaneous abortion,premature rupture of membranes,preterm birth and infertility and other adverse consequences,the delivery of mother to child transmission can cause neonatal inclusion conjunctivitis.[1] Today,as soon as the problem of improper use of antibiotics becoming increasingly serious,CT antibiotic resistance problem becoming increasingly prominent,the treatment is difficult.Therefore,the domestic and foreign researchers stdudy Chlamydia trachomatis infection and treatment deeperly and widerly.The researchers found that the Chlamydia phage can combine to the Chlamydia,then the Chlamydia remains in the reticular body stage and did not develop to the mature to infect,then the number of pathogens was decreased and abnormally larged reticular body appeared.These abnormally enlarged reticular bodies are similar to those that have been inhibited by interferon gamma,indicating that the phage has the potential for clinical treatment.Phage capsid protein vp1 is the main structural protein,it could play corresponding to the important role of chlamydia the membrane receptor proteins combined with adsorption.Chlamydia film adhesion,molecular weight is 61805,At the same time,it is the highly conserved and specific.[Objective] Express,identificate and purificate Vp1 capsid protein of guinea pig conjunctivitis Chlamydia phage phi CPG1,and applied to Chlamydia trachomatis strains E,K,observe its inhibitory effect.Intervene mice model reproductive tract infected of E Ct by Vp1 protein,observe the effects of VP1 on chlamydial trachomatis in the vagina of model mice.Intervene mice model reproductive tract infected of K Ct by Vp1 protein,observe the effects of VP1 on the upper infection of the reproductive tract in the model mice.[Methods] Express,identificate and purificate Vp1 capsid protein of guinea pig conjunctivitis Chlamydia phage phi CPG1.The standard strain E and K were incubated with 50?g/ml or 100?g/ml Vp1 protein for 3 hours at room temperature,type E or K Ct was inoculated to the monolayer of dense Mc Coy,adding Vp1 protein in culture of Chlamydia trachomatis.Then count iodine stained inclusion body to observe the effect of Vp1 protein on growth of Chlamydia trachomatis.Construct BALB/C female mice model of Ct type E infected vagina.With vaginal and intramuscular injection of Vp1 protein treatment,take the mouse vaginal secretions for cell culture and real-time PCR detection at different times,and observe swelling of the vaginal orifice of mice.Construct BALB/C female mice model of Ct type K infected vagina.With Vp1 protein intervention by the vagina,take the mouse uterus,fallopian tubes and ovaries for pathological biopsy,tissue homogenate cell culcure detection at different times.[Results] This experiment recombinant phage phi CPG1 capsid protein Vp1 can inhibit the growth of Chlamydia trachomatis,the standard strain E and K inclusions are reduced.Observe the average number of inclusion bodies of 2 standard strains,calculate the inhibition rate of 100ug/ml and 50ug/ml concentration Vp1.Vp1 inhibition rate,E type 91%,79%,K type 94%,70%.The BALB/C female mice model with the Ct standard strain E of the genital tract infection was successfully constructed.In different time collect mouse vaginal secretion for cell culture and real time PCR.Injection group and infection group and control group was no significant difference,Chlamydia concentration in vaginal intervention in high concentration group was lower than low concentration group,Chlamydia concentration in low concentration group was lower the control group and infection group,the difference was statistically significant.The BALB/C female mice model with the Ct standard strain K of the genital tract infection was successfully constructed.Vp1 protein intervention by vaginal administration,took mouse reproductive system 35 days after inoculation,observe the pathological changes of uterus,fallopian tube and ovary by HE staining,and the difference was statistically significant between the intervention group and the infection group.Chlamydia trachomatis was not detected in tissue homogenate real time PCR.[Conclusion] Guinea pig conjunctivitis Chlamydiaphage phi CPG1 capsid protein Vp1 had obvious inhibitory effect of Chlamydia trachomatis growth in cell culture in vitro.The Vp1 protein has inhibitory effect on Chlamydia trachomatis proliferation in mouse vaginal infection,the purification time of Chlamydia trachomatis in mouse vagina was shorten.The Vp1 protein has inhibitory effect on the upper genital tract inflammation in mice with genital Chlamydia trachomatis infection.Provided a new way to study the clinical treatment of Chlamydia trachomatis urinary tract infection.