Immunopathogenic consequences of Chlamydia trachomatis 60 kDa heat shock protein expression in the female reproductive tract

Global burden of female infertility attributable to sexually transmitted infections and maternal sepsis: 1990-2021 and projections to 2050

Infectious diseases, such as sexually transmitted infections (STIs) and maternal sepsis, are major contributors to female infertility, creating a substantial burden on women of reproductive age. Based on Global Burden of Disease (GBD) 2021, this study analyzed the global trends and regional disparities in infection-related infertility for women aged 15-49 and projected future burdens. Our result showed that from 1990 to 2021, global age-standardized prevalence rate (ASPR) rose from 839.52 to 982.37 per 100,000 with estimated annual percentage change (EAPC) (0.26 [0.19 to 0.33]), and years lived with disability (YLDs) increasing from 62.81 to 106.69 thousand (EAPC 0.23 [0.16 to 0.31]), and was predicted to continue rising from 2022 to 2050. The disease burden showed significant regional disparities, low socio-demographic index (SDI) regions had the highest ASPR (1247.25 per 100,000 [1085.17 to 1443.57]) but also the fastest decline (EAPC -1.17 [-1.34 to -0.99]), and Western Sub-Saharan Africa (ASPR 1,925.52 [1655.35 to 2241.71] per 100,000) are the regions with highest burden. The disease burden increased with age, peaking at 40-44 years, and was inversely associated with SDI. These findings provide essential insights for policymakers to develop targeted strategies to prevent and control infection-related infertility, particularly in low-SDI regions.

Comparative assessment of Chlamydia trachomatis pathogen prevalence, and the determination of host gyneco-epidemiological and immunological associated risk factors in female infertility

This study investigates the immunopathological responses to Chlamydia trachomatis (Ct) heat shock protein (Ct-Hsp) and their association with infertility. The objective was to explore the prevalence of anti-Ct antibodies and the gyneco-epidemiological risk factors for infertility among women attending a fertility clinic in Zaria, Nigeria, and to analyze the host immune cytokine or Ct-antigen levels in Ct-positive samples for correlation. From December 2022 to January 2024, 215 women (109 infertile and 106 fertile) from Ahmadu Bello University Teaching Hospital participated in this study. Endocervical specimens were tested for Ct-specific IgM and IgG antibodies to identify current and past infections. Additionally, antibodies to Ct-Hsp60, and cytokine levels of IFN-γ and IL-10, were measured using ELISA kits. The overall prevalence of Ct infection was 9.3 %. Past infection, indicated by IgG, was 40 %, while current infection, indicated by IgM, was 25 %. The remaining 35 % of Ct infection were detected by both immunological assay. Among infertile women, primary and secondary infertility prevalence was 41 % and 59 %, respectively. Serum IL-10 levels were significantly higher in Ct-positive infertile women compared to fertile controls. Serum IFN-γ levels were higher in Ct-negative fertile and infertile women than in Ct-positive cases. Serum Ct-Hsp60 levels were significantly higher in Ct-positive fertile women compared to infertile cases. The Th1/Th2 cell ratio was lower in both fertile and infertile women, regardless of Ct status, but fertile controls had a higher Th1/Th2 ratio compared to Ct-positive infertile women. Logistic regression identified significant infertility risk factors: vaginal discharge, age, second marriage, increasing years of childless marriage, and being over 35 years. Protective factors included anti-Ct IgM antibodies, teaching, lower education, and more children. Higher secondary infertility prevalence was linked to family planning history and reactivity to Ct-Hsp60. Ct-positive cases were associated with tubal factor and pelvic inflammatory disease infertility. This study highlights a low overall prevalence of Ct infection but a higher prevalence in women with tubal factor infertility, emphasizing the need for further research on cytokine responses in Ct-associated infertility.

Preconception Chlamydia trachomatis seropositivity and fecundability, live birth, and adverse pregnancy outcomes

OBJECTIVE

To study the impact of preconception Chlamydia trachomatis seropositivity on fecundability, live birth, and pregnancy loss and to assess the effect of low-dose aspirin therapy (81 mg/day) on live birth and pregnancy loss.

DESIGN

Preconception cohort study conducted using data and specimens from the Effects of Aspirin in Gestation and Reproduction study-a randomized placebo-controlled trial.

PATIENTS

A total of 1,228 individuals with proven fecundity and a history of 1-2 pregnancy losses.

EXPOSURE

Preconception C. trachomatis seropositivity determined using an enzyme-linked immunoabsorbent assay-based synthetic peptide assay at baseline.

MAIN OUTCOME MEASURES

Time-to pregnancy (fecundability) was defined as number of menstrual cycles to beta human chorionic gonadrotropin-detected pregnancy; live birth status was determined from medical record abstraction; pregnancy loss was defined as any loss post positive beta human chorionic gonadrotropin test.

RESULTS

After adjusting for confounders (baseline demographic and reproductive history variables), C. trachomatis seropositivity (n = 134/1228, 11%) was associated with a reduced live birth likelihood (relative risk [RR]: 0.77, 95% confidence interval [CI]: 0.59, 0.99) and an increased risk of pregnancy loss (RR: 1.16, 95% CI: 1.04, 1.29), but was not associated with fecundability (fecundability odds ratio: 0.92, 95% CI: 0.71, 1.20). Among a subset of C. trachomatis seropositive individuals with chronic inflammation indicated by increased C-reactive protein levels ≥1.95 but ≤10 mg/L (n = 50/134, 37.3%), low-dose aspirin therapy improved live birth rates (RR: 1.68, 95% CI: 0.96, 2.92) and reduced the risk of pregnancy loss (RR: 0.83, 95% CI: 0.65, 1.10). However, the sample size reduced precision.

CONCLUSIONS

Prior exposure to C. trachomatis among women with a history of pregnancy loss may impact risk of pregnancy loss. Our results indicate the need for future studies exploring mechanisms by which C. trachomatis may influence long-term reproductive function, because this may identify treatments to improve outcomes among those with a history of infection.

Fascinating Molecular and Immune Escape Mechanisms in the Treatment of STIs (Syphilis, Gonorrhea, Chlamydia, and Herpes Simplex)

The incidence of syphilis, gonorrhea, chlamydia, and herpes simplex has increased over the last decade, despite the numerous prevention strategies. Worldwide scientists report a surge in drug-resistant infections, particularly in immunocompromised patients. Antigenic variations in syphilis enable long-term infection, but benzathine penicillin G maintains its efficiency, whereas macrolides should be recommended with caution. Mupirocin and zoliflodacin were recently introduced as therapies against ceftriaxone-resistant gonococcus, which poses a larger global threat. The gastrointestinal and prostatic potential reservoirs of Chlamydia trachomatis may represent the key towards complete eradication. Similar to syphilis, macrolides resistance has to be considered in genital chlamydiosis. Acyclovir-resistant HSV may respond to the novel helicase-primase inhibitors and topical imiquimod, particularly in HIV-positive patients. Novel drugs can overcome these challenges while nanocarriers enhance their potency, particularly in mucosal areas. This review summarizes the most recent and valuable discoveries regarding the immunopathogenic mechanisms of these sexually transmitted infections and discusses the challenges and opportunities of the novel molecules and nanomaterials.

Female urogenital chlamydia: Epidemiology, chlamydia on pregnancy, current diagnosis, and treatment

Female urogenital chlamydia is a disease caused by Chlamydia trachomatis infection in the female urogenital tract. It is a common bacterial sexually transmitted disease. The bacteria is transmitted through sexual contact with an infected partner or from mother to newborn during vaginal delivery. The prevalence varies among studies and the number is possibly higher due to the lack of massive screening. Many patients were asymptomatic and still be able to transmit the disease. The undiagnosed and untreated disease could cause pelvic inflammatory disease, which leads to infertility, ectopic pregnancy, and chronic pelvic pain. The prevalence among pregnant women is similar to non-pregnant women, therefore chlamydia screening in pregnant women is highly recommended. The nucleic acid amplification test is the most reliable method for the diagnosis due to high sensitivity. The current treatment is given by prescribing antibiotics.

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Female urogenital chlamydia is caused by Chlamydia trachomatis.

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Urogenital chlamydia affects young and sexually active women.

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Female urogenital chlamydia is diagnosed through indirect methods (serology-based tests) and direct methods (culture).

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Treatment of chlamydia consists of antibiotics with doxycycline being the first-line choice.

Assisted Reproductive Technology Treatment, the Catalyst to Amplify the Effect of Maternal Infertility on Preterm Birth

OBJECTIVE

To identify the influence of different infertility causes and assisted reproductive technology (ART) treatment on perinatal outcomes and clarify the relationship between the maternal pathophysiological changes and artificial interventions.

METHODS

A total of 1,629 fertile women and 27,112 infertile women with sole infertility causes were prospectively recruited from July 2014 to December 2017, and 9,894 singletons were finally enrolled into the study. Pregnancies with more than one cause of infertility and/or multiple births were excluded. According to the causes of infertility and the exposure of ART treatment, the participants were divided into four groups, namely, fertile naturally conceived (NC) group, infertile NC group, female factor ART group, and male factor ART group. Perinatal outcomes, including gestational age of delivery (GA), birth weight (BW), preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA), and large for gestational age (LGA), were compared among groups. Logistic regression was performed for the adjustment of several covariates.

RESULTS

The birth outcomes of the infertile NC group and fertile NC group, female factor ART group, and infertile NC group were comparable. Compared to the fertile NC group, the female factor ART group had a shorter GA (39.0 ± 1.6 vs. 39.3 ± 1.5 weeks, BW: P < 0.05). An interaction test showed that ART treatment had an interaction on the effect of female infertility on GA (P = 0.023). The female factor ART group also had a higher risk of PTB (OR 1.56, 95% CI 1.18-2.07) and LGA (OR 1.27, 95% CI 1.10-1.47) compared to the fertile NC group. The risk of PTB was increased for tubal factor ART (OR 1.49, 95% CI 1.12-2.00), ovulatory dysfunction ART (OR 1.87, 95% CI 1.29-2.72), and unexplained infertility ART (OR 1.88, 95% CI 1.11-3.17). The risk of LGA was increased for tubal factor ART (OR 1.28, 95% CI 1.11-1.48) and ovulatory dysfunction ART (OR 1.27, 95% CI 1.03-1.57).

CONCLUSIONS

Our findings indicated that ART treatment could amplify the adverse effect of female infertility on neonates. Women with tubal factor infertility, ovulatory dysfunction, and unexplained infertility have a higher risk of PTB after ART treatment. Thus, clinicians should be vigilant in such patients and provide corresponding prevention strategies before and during pregnancy.

Revisiting Ehrlichia ruminantium Replication Cycle Using Proteomics: The Host and the Bacterium Perspectives

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.

The Impact of Selected Bacterial Sexually Transmitted Diseases on Pregnancy and Female Fertility

Sexually transmitted infections (STIs) caused by Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium are a common cause of pelvic inflammatory disease (PID) which can lead to tubal factor infertility (TFI). TFI is one of the most common causes of infertility, accounting for 30% of female fertility problems. STIs can also have an impact on pregnancy, leading to adverse pregnancy outcomes. Escalating antibiotic resistance in Neisseria gonorrhoeae and Mycoplasma genitalium represents a significant problem and can be therapeutically challenging. We present a comprehensive review of the current treatment options, as well as the molecular approach to this subject. We have given special attention to molecular epidemiology, molecular diagnostics, current and new treatments, and drug resistance.

Sexually transmitted infections in pregnancy - An update on Chlamydia trachomatis and Neisseria gonorrhoeae

Routine screening for Chlamydia and gonococcal infection in pregnancy is not widespread, especially in low- and middle-income countries (LMICs), despite their potential adverse consequences on pregnancy outcome. We conducted a systematic literature search of three major databases to review current literature surrounding Chlamydia trachomatis and Neisseria gonorrhoeae infections in pregnancy. We discuss the epidemiology and burden of both infections, detection methods, potential adverse feto-maternal and infant outcomes and provide an overview of treatment options. A total of 67 articles met the inclusion criteria. The prevalence of C. trachomatis and N. gonorrhoeae across all trimesters ranged between 1.0%-36.8% and 0-14.2% worldwide, respectively. The most common diagnostic method is the Nucleic acid amplification test (NAAT). In pregnancy, chlamydia is associated with preterm birth, spontaneous miscarriage, stillbirth and neonatal conjunctivitis, while gonorrhoea is mainly associated with preterm birth and stillbirth. Amoxicillin, erythromycin and azithromycin showed similar efficacy in the treatment of chlamydia in pregnancy, while ceftriaxone and cefixime were effective in treating gonorrhoea in pregnancy. Being largely asymptomatic infections in women, we opine that detection strategies with locally appropriate tools should be combined with the syndromic approach in LMICs, where there is a high burden of disease.

The association between vaginal microbiota and female infertility: a systematic review and meta-analysis

PURPOSE

This study aimed to explore the association between vaginal microbiota and infertility.

METHODS

We searched a range of electronic databases for appropriate articles, including PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure (CNKI), and Wanfang, from inception to 8th September 2019. Identified articles were then screened using strict inclusion and exclusion criteria. By referring to Tamarelle's method, we divided vaginal microbiota into two categories: low-Lactobacillus vaginal microbiota (LL-VMB) and high-Lactobacillus vaginal microbiota (HL-VMB). Patients were defined as HL-VMB if they had a Nugent score of 0-3, a negative Amesel/Spiegel's test, or if the vaginal community status was dominated by either L. crispatus, L. iners, L. gasseri and L. jensenii via 16S rRNA sequencing. Otherwise, cases were regarded as LL-VMB. Statistical analyses were performed with STATA 13.0 statistical software. Effect estimates are presented as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

Fifteen articles were included in our final analysis. The HL-VMB was negatively related to infertility; a fixed model showed that the pooled OR was 0.83 (95% CI 0.77-0.90). There was no significant publication bias, as determined by Begg's test (P = 0.488) and Egger's test (P = 0.652). Using a random effect model, the pooled OR for intermediate bacterial vaginitis (BV) and infertility was 1.39 (95% CI 1.10-1.76) and the pooled OR for positive BV was 1.72 (95% CI 1.10-2.69). Subgroup and sensitivity analyses further demonstrated that the associations identified were stable. However, the acquired evidence was not sufficient to make inferences with regards to the mechanisms underlying these relationships.

CONCLUSION

This systematic review and meta-analysis identified a negative correlation between HL-VMB and female infertility. However, due to a variety of limitations, the evidence acquired does not allow us to identify the specific mechanisms underlying this association. Further high-quality studies are needed to verify the causal relationship and explore the molecular mechanisms involved.

Influence of a mannose-binding lectin gene polymorphism and exposure to Chlamydia trachomatis on fallopian tube obstruction in Brazilian woman

PURPOSE

Factors influencing fallopian tube occlusion in women with a lower genital tract infection remain incompletely elucidated. We evaluated whether a polymorphism in the mannose-binding lectin (MBL) gene at codon 54 influences the occurrence of fallopian tube blockage in relation to exposure to Chlamydia trachomatis.

METHODS

In a case-control study at The Hospital das Clínicas, University of São Paulo, Brazil, 75 women with hysterosalpingography-documented tubal occlusion and 75 women with patent fallopian tubes were analyzed for detection of single-nucleotide polymorphism in codon 54 of the MBL gene and for IgG anti-C. trachomatis antibodies in their sera. Both groups were matched for age, race, and sexual variables.

RESULTS

Prior exposure to C. trachomatis, as evidenced by the presence of IgG antibodies, was comparable in both groups. Detection of the polymorphic MBL allele was more prevalent in women with blocked tubes (p < 0.01), regardless of whether or not there was evidence of prior chlamydial exposure.

CONCLUSION

The level of MBL-related innate immunity influences the consequences of infection by C. trachomatis or other microbes.

Chlamydia trachomatis: the Persistent Pathogen

Chlamydia trachomatis is an obligate intracellular bacterium whose only natural host is humans. Although presenting as asymptomatic in most women, genital tract chlamydial infections are a leading cause of pelvic inflammatory disease, tubal factor infertility, and ectopic pregnancy. C. trachomatis has evolved successful mechanisms to avoid destruction by autophagy and the host immune system and persist within host epithelial cells. The intracellular form of this organism, the reticulate body, can enter into a persistent nonreplicative but viable state under unfavorable conditions. The infectious form of the organism, the elementary body, is again generated when the immune attack subsides. In its persistent form, C. trachomatis ceases to produce its major structural and membrane components, but synthesis of its 60-kDa heat shock protein (hsp60) is greatly upregulated and released from the cell. The immune response to hsp60, perhaps exacerbated by repeated cycles of productive infection and persistence, may promote damage to fallopian tube epithelial cells, scar formation, and tubal occlusion. The chlamydial and human hsp60 proteins are very similar, and hsp60 is one of the first proteins produced by newly formed embryos. Thus, the development of immunity to epitopes in the chlamydial hsp60 that are also present in the corresponding human hsp60 may increase susceptibility to pregnancy failure in infected women. Delineation of host factors that increase the likelihood that C. trachomatis will avoid immune destruction and survive within host epithelial cells and utilization of this knowledge to design individualized preventative and treatment protocols are needed to more effectively combat infections by this persistent pathogen.

Sexually transmitted diseases and infertility

Female infertility, including tubal factor infertility, is a major public health concern worldwide. Most cases of tubal factor infertility are attributable to untreated sexually transmitted diseases that ascend along the reproductive tract and are capable of causing tubal inflammation, damage, and scarring. Evidence has consistently demonstrated the effects of Chlamydia trachomatis and Neisseria gonorrhoeae as pathogenic bacteria involved in reproductive tract morbidities including tubal factor infertility and pelvic inflammatory disease. There is limited evidence in the medical literature that other sexually transmitted organisms, including Mycoplasma genitalium, Trichomonas vaginalis, and other microorganisms within the vaginal microbiome, may be important factors involved in the pathology of infertility. Further investigation into the vaginal microbiome and other potential pathogens is necessary to identify preventable causes of tubal factor infertility. Improved clinical screening and prevention of ascending infection may provide a solution to the persistent burden of infertility.

Considerations for the rational design of a Chlamydia vaccine

Chlamydia trachomatis is the leading cause of preventable blindness and the most common bacterial sexually transmitted infection. Remarkable progress in vaccine research over the past six decades has led to the advancement of novel C. trachomatis vaccine candidates into clinical trials. However, many questions regarding the role of specific cellular populations and molecular mechanisms in protective immunity against human C. trachomatis genital tract infections remain unanswered. Biomarkers of vaccine induced protective immunity are elusive in humans, while a cautionary message on the translatability of data obtained from current animal models has emanated from vaccine research and development efforts against other important human pathogens. In this commentary, we highlight recent advances in Chlamydia vaccine development and discuss their implications in the context of a rational approach to the design of a human C. trachomatis vaccine.

Heat shock proteins: a therapeutic target worth to consider

Heat shock proteins (HSPs) are the molecular chaperones, that are not only expressed during the normal growth process of cell cycle consecutively, but also get induced in cells during various stress conditions produced by cellular insult, environmental changes, temperature, infections, tumors etc. According to their molecular weight and functions, HSPs are divided into five major families. HSP90, HSP70, HSP60 and HSP100 are the most studied members of the family. Experimental studies have proved that overexpression and/or inhibition of HSPs play an important role in maintaining the tolerance and cell viability under above-described stress conditions. HSP90 is found to be a promising the candidate for the diagnosis, prognosis and treatment of cancer. Similarly, HSP70, HSP60 and small HSPs experimentally and clinically have potential for the treatment of neurodegenerative disease, ischemia, cell death, autoimmunity, graft rejection, etc. In a way, exploring, the cytoprotective and immunoregulatory role of HSPs can open a new avenue for the drug discovery and treatment of critical diseases.

Interferon-gamma gene polymorphism influences the frequency of a Chlamydia trachomatis cervical infection in young women

Cervicitis associated with Chlamydia trachomatis is frequent worldwide, but the factors determining susceptibility to infection remain incompletely determined. We evaluated whether a functional single nucleotide polymorphism at position +874 in the gene coding for interferon gamma (rs2430561) influenced the likelihood of having a cervical C. trachomatis infection. This was a cross-sectional study of 142 sexually-active women attending a general gynaecology service on the outskirts of the city of Fortaleza in northeastern Brazil between August 2011 and August 2012. Endocervical swabs were evaluated for C. trachomatis DNA using hybrid capture. DNA from buccal swabs was utilised for detection of the interferon gamma 874 T/A single nucleotide polymorphism by gene amplification, endonuclease digestion and gel electrophoresis. Nineteen women (13.4%) were positive for C. trachomatis in their cervix. Positivity was 21.7% in women with the A,A genotype versus 7.0% in women with one or two T alleles (p = 0.0227). The variant T allele frequency, associated with elevated interferon gamma production, was 36.2% in women who were negative for C. trachomatis as opposed to 18.4% in women who were positive for a cervical infection with this organism (p = 0.0415). Possession of the T allele at position +874 in the gene coding for interferon gamma is associated with a reduced likelihood of a C. trachomatis cervical infection.

B-cell epitopes in GroEL of Francisella tularensis

The chaperonin protein GroEL, also known as heat shock protein 60 (Hsp60), is a prominent antigen in the human and mouse antibody response to the facultative intracellular bacterium Francisella tularensis (Ft), the causative agent of tularemia. In addition to its presumed cytoplasmic location, FtGroEL has been reported to be a potential component of the bacterial surface and to be released from the bacteria. In the current study, 13 IgG2a and one IgG3 mouse monoclonal antibodies (mAbs) specific for FtGroEL were classified into eleven unique groups based on shared VH-VL germline genes, and seven crossblocking profiles revealing at least three non-overlapping epitope areas in competition ELISA. In a mouse model of respiratory tularemia with the highly pathogenic Ft type A strain SchuS4, the Ab64 and N200 IgG2a mAbs, which block each other’s binding to and are sensitive to the same two point mutations in FtGroEL, reduced bacterial burden indicating that they target protective GroEL B-cell epitopes. The Ab64 and N200 epitopes, as well as those of three other mAbs with different crossblocking profiles, Ab53, N3, and N30, were mapped by hydrogen/deuterium exchange–mass spectrometry (DXMS) and visualized on a homology model of FtGroEL. This model was further supported by its experimentally-validated computational docking to the X-ray crystal structures of Ab64 and Ab53 Fabs. The structural analysis and DXMS profiles of the Ab64 and N200 mAbs suggest that their protective effects may be due to induction or stabilization of a conformational change in FtGroEL.

Recurrent miscarriages, innate immunity, and autoimmune reaction to chlamydial 60-kDa heat shock protein--is there an association?

OBJECTIVE

To evaluate a potential association of immunity to the Chlamydia trachomatis 60kDa heat shock protein (ChlamHSP60) and recurrent miscarriages.

DESIGN

Prospective study.

SETTING

Outpatient miscarriage clinic of a university-based hospital.

PATIENT(S)

120 asymptomatic women with a history of recurrent miscarriages.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Determination of serum immunoglobulin G (IgG) antibodies (Ab) to ChlamHSP60 and human HSP60 and, in parallel, mannose-binding lectin (MBL) and the total hemolytic complement (CH50); medical history and clinical examination, including multiple relevant laboratory determinants.

RESULT(S)

ChlamHSP60 Ab were detected in 24 (20%) of 120 patients. Antibodies to human HSP60 were found in 19 (15.8%) of 120 patients, and more frequently in individuals who tested positive for ChlamHSP60. ChlamHSP60 were statistically significantly associated with antichlamydial IgG Ab. However, antibodies to ChlamHSP60 were not related to medical history, the number of abortions, or the time frame of fetal loss. ChlamHSP60 antibodies were not associated with the relevant variables of the coagulation cascade, a panel of autoimmune parameters including thyroid autoimmunity, deficiencies of the complement system (low MBL), or with antibodies to common infectious diseases. No statistically significant differences were was found when comparing the prevalence of ChlamHSP60 Ab in the study group with recurrent miscarriages and 90 controls (women attending for an annual pelvic examination).

CONCLUSION(S)

Immunity to ChlamHSP60 does not play a major role in the etiology of recurrent miscarriages.

Prevalence and diagnostic significance of specific IgA and anti-heat shock protein 60 Chlamydia trachomatis antibodies in subfertile women

The objective of the present study was to evaluate the clinical usefulness of the simultaneous measurement of three serological markers of chlamydial infection in women with tubal factor infertility (TFI) and spontaneous miscarriage. Serum was collected from 87 patients (33 with TFI and 54 with spontaneous miscarriage) and analyzed for the presence of IgG and IgA antibodies against Chlamydia trachomatis MOMP antigen (Dia.Pro) and IgG antibodies to chlamydial heat shock protein 60 (cHSP60) antigen (Medac). We determined a high degree (64.5 %) of seropositivity against chlamydial antigens in our study population. The prevalence of persistent chlamydial infection has tended to be higher in the group of patients with TFI (41.4 %) than in patients with spontaneous miscarriage (21.3 %). The serum level of IgA, as a marker of active infection, was statistically higher in the TFI group with persistent infection than in the corresponding spontaneous miscarriage group (p = 0.008), while the serum level of IgG showed no statistically significant differences compared with the spontaneous miscarriage group with persistent infection (p = 0.227). Also, using the receiver operating characteristic (ROC) curve, we found that the serum level of IgA has the ability to discriminate patients with persistent chlamydial infection between the TFI and miscarriage groups, with a sensitivity and specificity of 74.3 % and 71.4 %, respectively. To the best of our knowledge, the present study is the first study which, besides the already confirmed linkage between serologic evidence of persistent chlamydial infection and TFI, also confirmed associations between spontaneous miscarriage and serologic evidence of persistent chlamydial infection.

Laboratory diagnosis of persistent human chlamydial infection

Diagnostic assays for persistent chlamydial infection are much needed to conduct high-quality, large-scale studies investigating the persistent state in vivo, its disease associations and the response to therapy. Yet in most studies the distinction between acute and persistent infection is based on the interpretation of the data obtained by the assays developed to diagnose acute infections or on complex assays available for research only and/or difficult to establish for clinical use. Novel biomarkers for detection of persistent chlamydial infection are urgently needed. Chlamydial whole genome proteome arrays are now available and they can identify chlamydial antigens that are differentially expressed between acute infection and persistent infection. Utilizing these data will lead to the development of novel diagnostic assays. Carefully selected specimens from well-studied patient populations are clearly needed in the process of translating the proteomic data into assays useful for clinical practice. Before such antigens are identified and validated assays become available, we face a challenge of deciding whether the persistent infection truly induced appearance of the proposed marker or do we just base our diagnosis of persistent infection on the presence of the suggested markers. Consequently, we must bear this in mind when interpreting the available data.

Tubal factor infertility and perinatal risk after assisted reproductive technology

OBJECTIVE

To assess trends of tubal factor infertility and to evaluate risk of miscarriage and delivery of preterm or low birth weight (LBW) neonates among women with tubal factor infertility using assisted reproductive technology (ART).

METHODS

We assessed trends of tubal factor infertility among all fresh and frozen, donor, and nondonor ART cycles performed annually in the United States between 2000 and 2010 (N=1,418,774) using the National ART Surveillance System. The data set was then limited to fresh, nondonor in vitro fertilization cycles resulting in pregnancy to compare perinatal outcomes for cycles associated with tubal compared with male factor infertility. We performed bivariate and multivariable analyses controlling for maternal characteristics and calculated adjusted risk ratios (RRs) and 95% confidence intervals (CI).

RESULTS

The percentage of ART cycles associated with tubal factor infertility diagnoses decreased from 2000 to 2010 (26.02-14.81%). Compared with male factor infertility, tubal factor portended an increased risk of miscarriage (14.0% compared with 12.7%, adjusted RR 1.08, 95% CI 1.04-1.12); risk was increased for both early and late miscarriage. Singleton neonates born to women with tubal factor infertility had an increased risk of preterm birth (15.8% compared with 11.6%, adjusted RR 1.27, 95% CI 1.20-1.34) and LBW (10.9% compared with 8.5%, adjusted RR 1.28, 95% CI 1.20-1.36). Significant increases in risk persisted for early and late preterm delivery and very low and moderately LBW delivery. A significantly elevated risk was also detected for twin, but not triplet, pregnancies.

CONCLUSION

Tubal factor infertility, which is decreasing in prevalence in the United States, is associated with an increased risk of miscarriage, preterm birth, and LBW delivery as compared with couples with male factor infertility using ART.

Potential mechanisms for increased HIV-1 transmission across the endocervical epithelium during C. trachomatis infection

Among the now pandemic sexually transmitted infections (STIs), Chlamydia trachomatis (C. trachomatis) is the predominant bacterial pathogen and human immunodeficiency virus type 1 (HIV-1) is the most lethal of the viral pathogens. The female genital tract is the primary site for heterosexual transmission of both C. trachomatis and HIV-1. Infection with C. trachomatis, and with a variety of other STIs, increases the risk for transmission of HIV-1, although the mechanisms for this finding remain unclear. We have used in vitro modeling to assess the mechanisms by which infection with genital C. trachomatis serovars might increase the transmission of HIV-1 across the female genital tract. C. trachomatis infection of an immortalized endocervical epithelial cell line (A2EN) increases the cell surface expression of the HIV-1 alternative primary receptor, galactosyl ceramide (GalCer), and of the HIV-1 co-receptors, CXCR4 and CCR5. C. trachomatis infection also increases the binding of HIV-1 to A2EN cells, and, subsequently, increases levels of virus in co-cultures of HIV-exposed A2EN and susceptible MT4-R5 T cells. Finally, in vivo endocervical cell sampling reveals a dramatic increase in the number of CD4+, CXCR4 and/or CCR5 positive T cell targets in the endocervix of C. trachomatis positive women when compared to those who are C. trachomatis negative. This combination of in vitro and in vivo results suggests several mechanisms for increased transmission of HIV-1 across the endocervices of C. trachomatis-infected women.

Heat-shock protein 60 kDa and atherogenic dyslipidemia in patients with untreated mild periodontitis: a pilot study

Identification of predictors of cardiovascular risk can help in the prevention of pathologic episodes and the management of patients at all stages of illness. Here, we investigated the relationships between serum levels of Hsp60 and dyslipidemia in patients with periodontitis by performing a cross-sectional study of 22 patients with mild periodontitis without any prior treatment for it (i.e., drug naïve) and 22 healthy controls, matched for age and body mass index (BMI). All subjects were evaluated for periodontal status, gingival inflammation, and oral hygiene. Levels of circulating Hsp60, C-reactive protein (CRP), and plasma lipids were measured, and small, dense low-density lipoproteins (LDL) were indirectly assessed by determining the triglycerides/high-density lipoproteins (HDL) cholesterol ratio. We also assessed by immunohistochemistry Hsp60 levels in oral mucosa of patients and controls. No difference was found in CRP levels or plasma lipids between the two groups, but subjects with periodontitis showed, in comparison to controls, higher levels of small, dense LDL (p  = 0.0355) and circulating Hsp60 concentrations (p < 0.0001). However, levels of mucosal Hsp60 did not change significantly between groups. Correlation analysis revealed that circulating Hsp60 inversely correlated with HDL-cholesterol (r  = -0.589, p  = 0.0039), and positively with triglycerides (r  = +0.877, p < 0.0001), and small, dense LDL (r  = +0.925, p < 0.0001). Serum Hsp60 significantly correlated with the degree of periodontal disease (r  = +0.403, p  = 0.0434). In brief, untreated patients with mild periodontitis had increased small, dense LDL and serum Hsp60 concentrations, in comparison to age- and BMI-matched controls and both parameters showed a strong positive correlation. Our data indicate that atherogenic dyslipidemia and elevated circulating Hsp60 tend to be linked and associated to periodontal pathology. Thus, the road is open to investigate the potential value of elevated levels of circulating Hsp60 as predictor of risk for cardiovascular disease when associated to dyslipidemia in periodontitis patients.

Identification of antigen-specific antibody responses associated with upper genital tract pathology in mice infected with Chlamydia muridarum

Urogenital infection with Chlamydia trachomatis in some women can lead to upper genital tract pathologies, such as hydrosalpinx, potentially affecting fertility. In the current study, 27 of 40 mice intravaginally infected with Chlamydia muridarum developed visible hydrosalpinges in the oviduct while the remaining 13 did not, although all infected mice displayed similar infection time courses. Antisera from the 40 mice recognized 130 out of 257 C. muridarum proteins as antigens and 17 as immunodominant antigens. Importantly, the 27 mice with hydrosalpinges preferentially recognized two C. muridarum proteins (TC0582 and TC0912, designated pathology-associated antigens) while the 13 mice with no hydrosalpinx preferentially recognized 10 proteins (TC0047, TC0117, TC0190, TC0197, TC0257, TC0279, TC0326, TC0630, TC0689, and TC0816, designated nonpathology antigens). The preferential recognition was validated by absorption and independently confirmed in Western blots. The C. trachomatis homolog of TC0912 is encoded by a highly polymorphic gene that is associated with ocular pathogenesis. A fragment of TC0912 was found to improve the differentiation of hydrosalpinx from nonhydrosalpinx mice. TC0582 is a highly conserved ATP synthase, and it may contribute to chlamydial pathogenesis via mechanisms similar to those hypothesized for the highly conserved HSP60. Thus, we have identified chlamydial antigens and epitopes that are associated with either susceptibility or resistance to upper genital tract pathology, which will help us to further understand chlamydial pathogenesis and to develop anti-Chlamydia subunit vaccines.

Antichlamydial antibodies, human fertility, and pregnancy wastage

Genital infections with Chlamydia trachomatis (C. trachomatis) continue to be a worldwide epidemic. Immune response to chlamydia is important to both clearance of the disease and disease pathogenesis. Interindividual responses and current chlamydial control programs will have enormous effects on this disease and its control strategies. Humoral immune response to C. trachomatis occurs in humans and persistent antibody levels appear to be most directly correlated with more severe and longstanding disease and with reinfection. There is a close correlation between the presence of antichlamydial antibodies in females and tubal factor infertility; the closest associations have been found for antibodies against chlamydial heat shock proteins. The latter antibodies have also been shown to be useful among infertile patients with prior ectopic pregnancy, and their presence has been correlated with poor IVF outcomes, including early pregnancy loss. We review the existing literature on chlamydial antibody testing in infertile patients and present an algorithm for such testing in the infertile couple.

Genome-wide identification of Chlamydia trachomatis antigens associated with tubal factor infertility

OBJECTIVE

To identify Chlamydia trachomatis antigens that can be used to differentially diagnose tubal factor infertility in comparison with previously reported heat shock protein 60.

DESIGN

In vitro study.

SETTING

Academic medical center.

PATIENT(S)

Infertile women with and without tubal pathology diagnosed laparoscopically.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Antibody responses to C. trachomatis in infertile women with or without tubal pathologies using a C. trachomatis genome-wide proteome array.

RESULT(S)

Comparison of the antibody profiles revealed 30 C. trachomatis antigens that were preferentially recognized in women with tubal factor infertility, with a detection sensitivity and specificity of 80.6% and 56.5%, respectively, 10 of which showed 100% specificity. A combination of CT443 and CT381 antigens yielded the highest detection sensitivity (67.7%) while maintaining 100% specificity.

CONCLUSION(S)

These findings have demonstrated that antibodies to CT443 and CT381, when used in combination, have higher sensitivity and specificity in predicting tubal factor infertility than other indicators for tubal factor infertility, such as heat shock protein 60 antibodies (35.5%, 100%) or hysterosalpingogram (65%, 83%). Using a panel of C. trachomatis antigens to serologically diagnose tubal factor infertility can save the patients from undertaking expensive and invasive procedures for determining tubal pathology and choosing treatment plans.