Seroprevalence of Chlamydia trachomatis Infection in Women of Procreate Age in the Mayo-Boneye Department in Chad

Introduction: Chlamydia trachomatis infections constitute a major public health problem, particularly in women. The objective of this study is to identify Chlamydia trachomatis to improve the health of women in the Department of Mayo-Boneye. Methodology: This is a prospective observational study that took place from October to December 2021, including 168 patients with their sociodemographic characteristics. The venous blood of the patients was collected in dry tubes and centrifuged to obtain the serum. The Chlamydia IgG Rapid Test Cassette was used for the detection of antibodies to Chlamydia infection. The Epi Info 7TM software was used to perform the statistical analyses. Results: A total of 168 patients were included in this study. The average age was 26.36 ± 9.21 years, the median was 25.5 years with the extremes of 14 years and 70 years. Among these patients, 46.43% were illiterate, 5.95% and 20.83% were primary and secondary school students, respectively, and 26.79% university students. For marital status, 66.67% were single, 16.67% married, 10.71% divorced and 5.95% widowed. Regarding the profession, 26.79% were traders, 8.93% were employees and 64.29% unemployed. In this study, the 168 patients had performed Chlamydia trachomatis serology among whom 02 (1.19%) were excluded for invalid results and 10.71% presented positive cases. The city of Bongor was the most infected with 61% of cases. Among these patients, 54.22% were linked to risk factors for Chlamydia trachomatis. The most infected age group was between 25 and 35 with a seroprevalence of 5.36% of cases. Conclusion: In this study, Chlamydia trachomatis was positive for 10.71% of diagnosed cases. The most affected age groups are young, sexually active women. The State should emphasize the screening of women, the awareness of students and academics.

Evaluation of patients with dry eye disease for conjunctival Chlamydia trachomatis and Ureaplasma urealyticum

AIM：To determine the possibility of the development of dry eye disease（DED） as a result of persistent infection with Chlamydia trachomatis and Ureaplasma urealyticum in the conjunctiva of patients.METHODS： This study was conducted on 58 patients of age range 20-50 y,diagnosed with DED confirmed by Schirmer I test and tear breakup time.The non-dry eye control group included 27 subjects of the same age.Ocular specimens were collected as conjunctival scrapings and swabs divided into three groups： the first used for bacterial culture,the second and third taken to detect Chlamydia trachomatis and Ureaplasma urealyticum by direct fluorescent antibody（DFA） assay and polymerase chain reaction（PCR） method. RESULTS： Chlamydia trachomatis was detected in 65.5% and 76% of DED patients by DFA and PCR methods respectively.Ureaplasma urealyticum was found in 44.8% of DED infected patients using the PCR method.Both organisms were identified in only 37.9% of DED patients found to be infected.Control subjects had a 22%detection rate of Chlamydia trachomatis by DFA assay versus a 7% detection rate by PCR; while Ureaplasma urealyticum was detected in 3.7% of the controls by PCR method.The conjunctival culture revealed that gram positive microorganisms represented 75% of isolates with coagulase negative Staphylococci the most common（50%） followed by Staphylococcus aureus（20%）,whereas gram negative microorganisms occurred in 25% of cases,isolating Moraxella spp.as the most frequent organism. CONCLUSION： Our results tend to point out that Chlamydia trachomatis and Ureaplasma urealyticum were detected in a moderate percentage of patients with DED,and could be a fair possibility for its development.PCR is more reliable in detecting Chlamydia trachomatis than DFA technique.The presence of isolated conjunctival bacterial microflora can be of some potential value.

Study of the prevalence and association of ocular chlamydial conjunctivitis in women with genital infection by Chlamydia trachomatis, Mycoplasma genitalium and Candida albicans attending outpatient clinic

AIMTo determine the association between chlamydial conjunctivitis and genital infection by Chlamydia trachomatis, Mycoplasma genitalium and Candida albicans, in addition to the possible relationship between cultured bacterial pathogens and oculogenital chlamydial infection.METHODSThis study was performed on 100 (50 symptomatic and 50 asymptomatic) women attending the Gynecological and Obstetric outpatient clinic of Alzahra hospital, Alazhar University. Simultaneously a conjunctival swab was taken from these patients. Polymerase chain reaction (PCR) was done on DNA extracted from both vaginal and conjunctival swab samples. Culture for both vaginal and conjunctival swabs was also done.RESULTSCandida albicans was the predominant organism isolated by culture in 20% and 40% of conjunctival and vaginal swabs respectively. By the PCR method, ocular Chlamydia trachomatis was present in 60% of symptomatic women, while genital Chlamydia trachomatis infection was present in 30% of symptomatic women. The results of this method also indicated that 25/50 (50%) vaginal swabs were positive with PCR for Candida albicans versus 15/50 (30%) were PCR positive in conjunctival swab. Mycoplasma genitalium was present in only 10% of vaginal swabs. Concomitant oculogenital PCR positive results for Chlamydia trachomatis and Candida albicans were 30% and 28% respectively.CONCLUSIONOcular Chlamydia trachomatis was associated with genital Chlamydia trachomatis in a high percentage of women followed by Candida albicans. Cultured bacterial organisms do not play a role in enhancement of Chlamydia trachomatis infection.

High frequency of latent Chlamydia trachomatis infection in patients with rhegmatogenous retinal detachment

AIM： To determine the frequency of detection of ocular and extraocular Chlamydia trachomatis （CT） infection in non -high myopes with rhegmatogenous retinal detachment （RRD）. METHODS： This was a single-center, nonrandomized, prospective, case-control study. One hundred and four patients were divided into a study group with RRD （n= 63） and a control group with traumatic retinal detachment （n=41）. Samples of subretinal fluid （SFR）, conjunctival, urethral/cervical swabs, and blood were collected. The frequency of detection of CT infection in SRF samples was determined by polymerase chain reaction （PCR）, direct fluorescence assay （DFA） and cell culture, whereas that in conjunctival swabs was determined by PCR and DFA, and those in urethral/cervical swabs and blood were determined by DFA. Yates Chi-square test （with Bonferroni correction） and two-tailed Student＇s t-test were used for statistical analysis. RESULTS： SRF CT infection was detected more frequently in the study group （50.8%-71.4%） than in the control group （9.8%-12.2%） by all the methods used （P〈 0.01）. The frequency of detection of conjunctival CT infection by DFA was higher in the RRD patients compared with the controls （81.0% vs 24.4%, P=0.004）. The PCR detected conjunctival CT infection more often in the study group than in the controls （46.0% vs89.8%, P= 0.007）. The DFA detected CT in blood specimens almost as frequently as in urogenital specimens, for the RRD patients （61.2% vs 63.5%） and the controls （7.3% vs 9.8%）. CONCLUSION： CT infection is detected with high frequency in non-high myopes with RRD.

Trichomonas vaginalis and Chlamydia trachomatis Prevalence,Incidence and Associated Factors in Pregnant Adolescents from Belém City,in the Brazilian Amazon

Background: Adolescents are disproportionally affected by sexually transmitted infections (STI). Chlamydia trachomatis (CT) and Trichomonas vaginalis (TV) are the most frequent curable STI in adolescents, causing serious consequences for their reproductive health. Therefore, we aimed to determine the prevalence and incidence of CT and TV, as well as their risk factors in pregnant adolescents from Belém, northern Brazilian Amazon. Methods: This prospective study enrolled 199 adolescents up to 20 weeks of pregnancy. They were scheduled for follow-up visit between 28 and 29 weeks of pregnancy. Sociodemographic and behavioral data were obtained by interview. Cervicovaginal samples were taken to test for TV, CT, Neisseria gonorrhoeae and bacterial vaginosis. Univariate and multivariate analyses were performed to test the association of prevalent/incident CT and TV with the variables. Results: Prevalence of cervical CT infection was 33.7% (n = 67/ 199), and for trichomoniasis it was 4.0% (n = 8/199). Cervical ectopy increased the risk for prevalent CT (OR, 1.93;95% CI, 1.01 - 3.70), while having treated vaginal discharge in the past (OR, 0.51;95% CI, 0.26 - 0.98) and being married (OR, 0.10;95% CI, 0.01 - 0.83) were protective against current CT and TV, respectively. Among the 95 (47.7%) adolescents who completed follow-up, 15 cases of incident CT were identified. Incident CT was associated with having a formal or informal job (OR, 28.4;95% CI, 2.1 - 391.6) and bacterial vaginosis treatment at the baseline (OR, 0.08;95% CI, 0.01 - 0.69). Conclusion: Prevalence and incidence rates of TV and CT are high in this population devoid of STI routine screening. Treatment of bacterial vaginosis may benefit this population by reducing risk for CT acquisition.

Immunohistochemical Analysis of TNF-α and HSP-60 in Women with Tubal Factor Infertility Associated with Chlamydia Trachomatis

Summary: To explore the roles of tumor necrosis factor-α (TNF-α) and heat shock protein 60 (HSP-60) in women with tubal factor infertility (TFI) associated with Chlamydia trachomatis, and to determine the mechanisms of fallopian adhesions in Chlamydia trachomatis (CT) infections, the expressions of TNF-α and HSP-60 were quantitatively determined in 60 cases of TFI and 30 controls by immunohistochemical technique. The patients with TFI were further divided into group A and group B according to the CT-DNA of cervical specimens of PCR. The quantitative analysis was conducted by employing computerized image analysis system. It is found that the expressions of TNF-α and HSP-60 were much higher in TFI patients than those of controls. Among CT-HSP responders, a stronger expression was correlated with more severe salpingeal pathology. It is concluded that TNF-α and HSP-60 play very important roles in fallopian tube adhesion and occlusion in TFI due to CT infection.

A Simple Method of Detecting Chlamydia Trachomatis UsingEnzymatically Amplified DNA and Immobilized Probes onMicrotiter Plate

We have develoPed a simPle and economical method f0r Chlamydia trachomatisdetecting, called microtiter plate hybridization (PCR-MPH), which may replace stan-dard PCR. This method is similar to that of an ELISA. Brithe, the PCR productslabeled at the 5'termini with biotin were hybridized with probes immobilized on a mi-crotiter well, and the bound PCR products were detected by streptavidin-c0njugatedenzymes followed by color development. Two inprovements have been made in immobi-lizing the probe to the microtiter wells, in terms of increasing both immobility and hy-bridization deciency. One is that singleustranded (ss )DNA, without the complemen-tary strand, is used. The other is that instead of a single copy, a tandem array of theprobe is used for immobilization and hybridization. Using of ssDNA containing abouta 5O-rePeat array of a relevant sequence as an immobilized probe, the sensitivity in-creased 1O-fold over that of a single oligonucleotide unit. We also found that the hy-brldizatlon condltions such as time, temPerature, and solution composition could be simplthed. The advantages of this microtiter plate-hybridization method for routinepathogens detecting are a short time assay, easy processing of large numbers of sansples, and the potential for automation.

The Association between <i>Chlamydia Trachomatis</i>and Ectopic Pregnancy in Lagos, Nigeria—A Case Control Study

Objectives: To determine the seropositivity of Chlamydia antibody in patients with ruptured ectopic pregnancy compared to normal pregnant women and the risk factors for ectopic pregnancy. Study Design: This was a prospective case-control study of 85 cases of ruptured ectopic pregnancy and 100 cases of second trimester on-going intrauterine pregnant controls presenting in Lagos State University Teaching Hospital (LASUTH) between September 2009 and March 2010. Study Site: This was at the gynaecological emergency room and antenatal clinic in the Department of Obstetrics and Gynaecology. Ethical approval was sought and granted by the ethics review committee of LASUTH. Study Participants: Patients presenting with ruptured ectopic pregnancy were recruited as cases while the controls were made up of those with uncomplicated second trimester intrauterine pregnancy. A semi-structured questionnaire containing socio-demographic and clinical characteristics was administered following informed consent. Five milliliters of venous blood was taken from each participant and tested for?Lymphogranuloma Venerum?(LGV) type 2 broadly reacting antigen of?Chlamydia trachomatis.?Data Analysis: Data gathered from the case notes and laboratories were imputed into the computer and analyzed using the statistical package?Epi-Info 3.51, Atlanta, USA. Frequency tables were generated for continuous variables and?chi-square analysis used to determine association between variables, with p values <0.05 considered statistically significant. Results: There were 91 cases of ectopic pregnancy among a total of 2468 deliveries giving an incidence of 3.68% or 1 in 27 deliveries. Factors which significantly contributed to increased incidence of ectopic pregnancy in this study were: level of education (p = 0.001), socio-economic status (p = 0.001), parity (p = 0.005), early age of sexual debut (p = 0.001), multiple sexual partners (p = 0.001), previous pelvic inflammatory disease (p = 0.003), previous induced abortion (p = 0.013) and previous?postabortal/puerperal sepsis (p = 0.013). The seropositivity of?Chlamydia IgG (62.4%) in the cases was significantly higher than that of 29% in the control (p < 0.0001). Conclusion: There was a high incidence of ectopic during the period of study and the seropositivity of Chlamydia IgG antibody was significantly higher amongst the cases. Risk factors identified were low level of education, low socio-economic status, low parity, early age of sexual debut, multiple sexual partners, previous history of pelvic inflammatory disease, previous induced abortion and previous postabortal/puerperal sepsis.

Detection of <i>Chlamydia trachomatis</i>and <i>Neisseria gonorrhoeae</i>in Egyptian Women Suffering from Infertility

Chlamydial and gonococcal infections are recognized as two of the major causes of sexually transmissible human bacterial infection which may lead to infertility. In this cross sectional study, we aimed to determine the prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis among Egyptian women using different microbiological methods. One hundred and fifty cervical swabs were collected, of which 100 were from infertile women. Culture and ELISA technique were used for screening of Neisseria gonorrhoeae and Chlamydia trachomatis individually. In addition, PCR was used for all examined samples. For C. trachomatis, 3 cases were positive for antigen detection by ELISA. Moreover, in obtained results of PCR, DNA was detected in 4 samples, and three of them from infertile group. So based on PCR results, the sensitivity and specificity of ELISA were 75% and 100% respectively. Furthermore, 3 samples were positive for gonococcal infections by PCR, and two of them were taken from infertile women. Positive results of two samples were verified by culture. The estimated sensitivity and specificity of culture method were 66.7% and 100% respectively. Results of this study indicate that PCR is a valuable method for detection of gonococcal and chlamydial infection and it is suitable for the confirmation of ELISA results for C. trachomatis diagnosis. Culture method is less sensitive than PCR for detection of N. gonorrhoeae. The prevalence of such infections is higher among infertile women.

Characterization of Chlamydia trachomatis omp1 gene among sexually transmitted disease patients in south China

To investigate the DNA sequence polymorphism of Chlamydia trachomatis omp1 gene, urogenital samples were collected from 4 different cities in South China, DNA was extracted, and an approximately 980-bp-long fragment of the omp1 gene was amplified by nested polymerase chain reaction (nPCR). DNA sequence was determined, genotyping was performed by BLAST similarity search, and multiple alignment was performed with CLUSTAL X. Then a phylogenetic tree was constructed by Mega 3 software to illustrate the evolutionary relationships between clinical isolates and reference strains. Ninety-six specimens were sequenced, and 28 genetic variants were detected, among which E was the most prevalent genotype. The omp1 gene was highly conserved for genotypes E and F, but appeared slightly less conserved for other genotypes, where the sequences displayed one to several nucleotide substitutions relative to the reference sequence. Phylogenetic tree showed that C.trachomatis serotypes were mainly divided into three clusters, according to previous grouping in the B, F-G, and C complexes, and the clinical isolates were highly related to the corresponding reference strains. It concluded that the omp1 gene of the isolated C.trachomatis strains exhibited remarkable DNA sequence polymorphism, which can encourage for vaccine design and infection control.

<i>Chlamydia trachomatis</i>in a girl suspected of sexual abuse in the city of Córdoba, Argentina

Chlamydia trachomatis (C.tr) infections are the most prevalent bacterial sexually transmitted infections worldwide. They are often asymptomatic and therefore underdiagnosed as there is no routine screening surveillance. This case supports the possibility of sexual abuse as a route of transmission of C.tr. It is well known that nearly one third of sexually assaulted children are at risk for infection by a sexually transmitted agent. This is why in cases of sexual abuse, it is standardized that C.tr positive results by Nucleic Acid Amplification Techniques (NAATs) should be confirmed looking for another C.tr target;for this reason, we used a Polimerase Chain Reaction (PCR) directed to cryptic plasmid of C.tr. Confirmation was specified by the use of another PCR with a different genetic target (ompA) and sequencing. We concluded that our patient’s oral lesions were probably originated by her father’s sexual abuse.

Biological Effects of Chlamydiaphage phi CPG1 Capsid Protein Vp1 on Chlamydia Trachomatis In Vitro and In Vivo

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 phi CPG1 capsid protein Vp1 on Ct both in Mc Coy cells and genital tract of mice. Different concentrations of Vp1 were co-incubated with Ct E serotype strain in Mc Coy 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/m L and 50 μg/m L Vp1 proteins against Ct E strain in the Mc Coy cell cultures was 91% and 79% respectively. The number of intracellular Ct inclusion in the Mc Coy 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 10 th 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.

Research Progress on Chlamydia trachomatis Infection and Related Cytokines

Chlamydia trachomatis (Ct) infection can induce host cells to produce numerous cytokines.Cytokines play important roles in inflammatory response. Although inflammation can protect the body, persistent inflammation can lead to pathological changes and tissue damages. Further research should determine whether cytokine production directly affects development and outcomes of inflammation. This study summarizes Ct infection and related cytokines.

manClinical Study on Infection of Chlamydia Trachomatis in Patients with Inflammation of Urogenital Tract

Object: To investigate the relationship between chlamydia trachomatis (CT) and urogenital infection. Method: Positive rate of CT in patients with inflammation of urogenital tract was significantly higher than those without inflammation (P<0.05). Result: There was statistical difference in the males nomatter they were patients with inflammation of urogenital tract or not (P>0.05), while there was no statistical difference in females (P>0.05). The incidence of the infection was highamong those aging from 21-50 years old. Conclusion: The clinical manifestations of CT infection were obscure, so we should examine CT in patients who have no symptoms, especially in females and those of high-risk population.

Vidas CHL Assay in the Detection of Urogenital Chlamydia Trachomatis Infection

Objectives: To evaluate the Vidas Chlamydia(CHL)assay for detecting C.Trachomatis with swabs and first catch urine(FCU) specimens from STD patients and high risk populations. Methods: A total of 383 patients were tested with tissue culture (TC), Vidas CHL and polymerase chain reaction (PCR)for C.trachomatis on male and female swabs, with Vidas CHL testing male FCU specimens. CHL positive and equivocal results were confirmed with a blocking assay (CHB). True positive were defined as either TC positive, or TC negtive but CHL and PCR positive. The performance of TC, CHL and PCR were evaluated according to this expanded gold standard. Results: Compared with the expanded gold standard, 54 of the 232 male specimens were true positive results. For male swabs, TC, CHL and PCR had sensitivities of 90.7%, 96.3% and 94.4%, and specificities of 100%, 98.3% and 97.2%,respectively. Differences were not statistically significant. For male FCU specimens, CHL sensitivity and specificity were 83.3% and 98.3%; there was little difference between these results and that of matched swabs. Compared with the expanded gold standard, 28 of the 151 female swabs were true positive; TC, CHL and PCR had sensitivities of 82.1%, 100% and 96.4%, and specificities of 100%, 98.4% and 97.6%,respectively. The difference was also not significant. Conclusions: Vidas CHL assay is very sensitive and specific for C.trachomatis detection with swab specimens of male andfemale STD patients. For male FCU specimens, the assay also had high sensitivity and specificity. CHB may not be needed inthe routine detection of Chlamydia infections. Population swith higher incidence of C.trachomatis infection.

Partner's Sexual Behaviora are an Important Risk Factor for Chlamydia Trachomatis Infection among STD Patients

Summary: Risk factors for genitourinary Chlamydia trachomatis (Ct) infection were investigated using an STD relative risk factor questionnaire among 176 patients and their regular sexual partners. Twenty-four independent variables were selected for analysis, nine of which were confirmed as factors associated with C. trachomatis. Four of the nine factorswere significantly correlated to infection using a multifactorialunconditional logistic regression model which included: levelof education ( odds ratios [ORs]: 2.144 for below junior middleschool ), number of sexual partners ( ORs: 4.503 for≥5 ),number of regular partner's sexual partner ( ORs: 16.333 for≥5 ), STD history of regular partner ( ORs: 18.417 for theirSTD history ). These data demonstrate that regular partner'ssexual behaviors are also an important risk factor for Ctinfection among, STD clinic clients.

Establishment of a Two-site ELISA for Detection of Chlamydia Trachomatis

Objective:To establish a rapid and simple assay for the diagnosis of Chlamydia trachomatis (CT) infection. Methods BALB/c mice were immunized with SDS-PAGE purified major outer membrane protein (MOMP) from CT and the monoclonal antibodies were obtained subsequently. Two-site ELISA was developed to detect CT infection. Results: The established assay was able to detect as low as 1.248ug/ml MOMP with interrun and inrun CV 6.9% and 3.1% respectively. 94% (34/36) of culture-positive samples were found to be positive in the current examination, indicating the high sensitivity of this assay. Conclusion: The assay is applicable for clinical diagnosis of CT infection.

鹦鹉热衣原体肺炎的CT表现特征

目的探讨鹦鹉热衣原体肺炎患者的CT表现特征。方法回顾性分析笔者医院经宏基因二代测序(macrogene second-generation sequencing,m NGS)技术确诊10例鹦鹉热衣原体肺炎患者的胸部CT图像。结果7例(70%)患者与鸟(禽)类或其粪便有接触史。入院胸部CT均表现为团片状渗出实变影,均位于单肺,其中累及单叶8例(80%)、双叶2例(20%);10例(100%)均伴有支气管充气征,9例(90%)有磨玻璃影,8例(80%)局部小叶间隔或小叶内间隔增厚;1例(10%)病灶呈“扇形”改变,1例(10%)病灶见“反晕症”,9d内复查9例(90%)有进展,表现为病灶融合增大呈更大范围实变或新出现病灶。结论鹦鹉热衣原体肺炎CT表现具有一定特征,结合鸟(禽)类接触史可提示诊断。

Chlamydia trachomatis and sperm lipid peroxidation in infertile men

<abstract>Aim: To relate the presence of anti-Chlamydial trachomatis IgA in semen with sperm lipid membrane peroxidation and changes in seminal parameters. Methods: Semen samples of the male partners of 52 couples assessed for undiagnosed infertility were examined for the presence of IgA antibody against C. trachomatis. The level of sperm membrane lipid peroxidation was estimated by determining the malondialdehyde (MDA) formation. Results: Sperm membrane of infertile males with positive IgA antibodies against C. trachomatis showed a higher level of lipid peroxidation than that of infertile males with negative IgA antibody (P<0.05). There was a positive correlation (P< 0.01) between the level of C. trachomatis antibody and the magnitude of sperm membrane lipid peroxidation. All the other tested semen parameters were found to be similar in the two groups. Conclusion: The activation of immune system by C. trachomatis may promote lipid peroxidation of the sperm membrane. This could be the way by which C. trachomatis affects fertility.

Expression and Purification of the Major Outer Membrane Protein of Chlamydia Trachomatis in Prokaryotic Cell

To clone and construct the recombinant plasmid containing the major outer membrane protein (MOMP) gene of Chlamydia trachomatis (C.trachomatis) and to express the fusion protein in E.coli BL21, the MOMP gene was amplified by polymerase chain reaction (PCR) from genome of C.trachomatis serovar D. The fragment was cloned into the prokaryotic expression vector pET-22b(+) after digestion with BamHⅠ and NotⅠ and transformed into E.coli XL1-Blue. Recombinants were selected by enzyme digestion and sequencing and the recombinant plasmid with MOMP gene was then transformed into E.coli BL21 with IPTG to express the target gene. The expression recombinant proteins were purified by Ni-NTA affinity chromatography, and identified by SDS-PAGE and Western blot. It was found that a 1.2?kb MOMP gene was isolated. The DNA sequence of MOMP was found to be just the same as the sequence published by GenBank. A recombinant plasmid containing MOMP gene was constructed to express the fusion proteins in E.coli. SDS-PAGE analysis showed that the relative molecular weight of the recombinant protein was about 47?kDa that was consistent with the theoretical predicted value, and the specificity of the expressed protein was conformed by Western blot. It concluded that the MOMP gene could be expressed in the prokaryotic system, by which it provided the foundation for the future studies on the biological activities of C.trachomatis and for the development of vaccine against this pathogen.