Trachomatis Organisms Research Articles

Multilocus VNTR analysis-ompA typing of Chlamydia trachomatis isolates in Tehran, Iran

IntroductionThis study is the first to describe the genetic diversity of C. trachomatis strains derived from patients with signs and symptoms of genitourinary infections admitted to Tehran health centers and hospitals using the high-resolution genotyping method, multilocus variable-number tandem-repeat analysis with ompA sequencing (MLVA)-ompA. MethodsOne hundred and sixty-seven urogenital specimens were collected from October 2019 to July 2020. Specimens were inoculated to cell culture and examined for the presence of C. trachomatis isolates by microscopic valuation. Out of 167 samples, 19 (11.3%) viable C. trachomatis organisms were isolated in cell culture. Eighteen isolates were successfully genotyped by MLVA-ompA analysis. ResultsThe most prevalent ompA genotypes were E, D, F and G, comprising 42%, 26.3% and 21% and 10.5% of isolates, respectively. Other genotypes were not detected from any of the samples. Out of the 18 fully genotyped isolates, 10 different MLVA-ompA genotypes were obtained. The most prevalent MLVA-ompA genotypes were 8.6.1-E (33.3%) and 8.5.2-D (16.6%). Genotype 8.6.1-E was common in both females and males. ConclusionsOur results showed that MLVA-ompA analysis was more discriminatory than ompA typing alone and, therefore, a suitable complement to ompA. Using this method, dominant genotypes in the community and transmission patterns in sexual networks could be identified. The high diversity of C. trachomatis strains in Tehran may be due to the low level of public health and awareness, and future studies are needed.

Association of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Ureaplasma species infection and organism load with cervicitis in north Indian population.

Cervicitis is predominantly caused by Neisseria gonorrhoeae and Chlamydia trachomatis, which accounts for almost half of all the cases of cervicitis. The role of newer organisms like Mycoplasma genitalium and Ureaplasma sp. and association of bacterial load with cervicitis are also not well established. So the study aimed to determine the relative frequency of these organisms and their load in association with cervicitis cases from north India. A case-control study involving 300 women was conducted using quantitative real-time PCR from endocervical swabs for identification of organisms and quantification of bacterial load. Among 150 cervicitis cases, C. trachomatis, N. gonorrhoeae, M. genitalium and Ureaplasma parvum were detected in 5 (3·3%), 10 (6·6%), 37(24·6%) and 47 (31·3%) respectively. Old age (<0·001, chi-squared test) and irregular menstrual cycles (<0·001, chi-squared test) were significantly associated with cervicitis. M genitalium was the only organism to be associated significantly with cervicitis with regard to age (<0·031) and symptoms like discharge (P<0·033, chi-squared test) and dysuria (P<0·044, chi-squared test) in multivariate analysis. Our finding suggests that the bacterial load of these organisms is not significantly associated with cervicitis. However, we found significant association of M. genitalium infection with clinical characteristics of cervicitis cases.

Proteome array of antibody responses to Chlamydia trachomatis infection in nonhuman primates

AimsNonhuman primates have been used to investigate pathogenic mechanisms and evaluate immune responses following Chlamydia trachomatis inoculation. This study aimed to systemically profile antibody responses to C. trachomatis infection in nonhuman primates. Materials and methodsSera were obtained from 4 pig-tailed and 8 long-tailed macaques which were intravaginally or ocularly infected with live C. trachomatis organisms, and analyzed by C. trachomatis proteome array of antigens. Key findingsThe sera from 12 macaques recognized total 172 C. trachomatis antigens. While 84 antigens were recognized by pig-tailed macaques intravaginally infected with serovar D strain, 125 antigens were recognized by long-tailed macaques ocularly infected with serovar A, and 37 antigens were recognized by both. Ocular inoculation with virulent A2497 strain induced antibodies to more antigens. Among the antigens uniquely recognized by A2497 strain infected macaques, outer membrane complex B antigen (OmcB) induced robust antibody response. Although macaques infected by less virulent A/HAR-13 strain failed to develop antibodies to OmcB, reinfection by A2497 strain induced high levels of antibodies to OmcB. SignificanceProteome array has revealed a correlation of chlamydial infection invasiveness with chlamydial antigen immunogenicity, and identified antibody responses to OmcB potentially as biomarkers for invasive infection with C. trachomatis.

Impact of a single round of mass drug administration with azithromycin on active trachoma and ocular Chlamydia trachomatis prevalence and circulating strains in The Gambia and Senegal

BackgroundMass drug administration (MDA) with azithromycin is a cornerstone of the trachoma elimination strategy. Although the global prevalence of active trachoma has declined considerably, prevalence persists or even increases in some communities and districts. To increase understanding of MDA impact, we investigated the prevalence of active trachoma and ocular C. trachomatis prevalence, organism load, and circulating strains at baseline and one-year post-MDA in The Gambia and Senegal.MethodsPre- and one-year post-MDA, children aged 0–9 years were examined for clinical signs of trachoma in six Gambian and 12 Senegalese villages. Ocular swabs from each child’s right conjunctiva were tested for evidence of ocular C. trachomatis infection and organism load (ompA copy number), and ompA and multi-locus sequence typing (MLST) was performed.ResultsA total of 1171 children were examined at baseline and follow-up in The Gambia. Active trachoma prevalence decreased from 23.9% to 17.7%, whereas ocular C. trachomatis prevalence increased from 3.0% to 3.8%. In Senegal, 1613 and 1771 children were examined at baseline and follow-up, respectively. Active trachoma prevalence decreased from 14.9% to 8.0%, whereas ocular C. trachomatis prevalence increased from 1.8% to 3.6%. Higher organism load was associated with having active trachoma and severe inflammation. Sequence typing demonstrated that all Senegalese samples were genovar A, whereas Gambian samples were a mix of genovars A and B. MLST provided evidence of clustering at village and household levels and demonstrated differences of strain variant frequencies in Senegal, indicative of an “outbreak”. MLST, including partial ompA typing, provided greater discriminatory power than complete ompA typing.ConclusionsWe found that one round of MDA led to an overall decline in active trachoma prevalence but no impact on ocular C. trachomatis infection, with heterogeneity observed between villages studied. This could not be explained by MDA coverage or number of different circulating strains pre- and post-MDA. The poor correlation between active trachoma and infection prevalence supports the need for further work on alternative indicators to clinical signs for diagnosing ocular C. trachomatis infection. MLST typing has potential molecular epidemiology utility, including better understanding of transmission dynamics, although relationship to whole-genome sequence variability requires further exploration.

Neutralizing antichlamydial activity of complement by chlamydia-secreted protease CPAF

Ascending infection by sexually transmitted Chlamydia trachomatis is required for chlamydial induction of tubal pathology. To achieve ascension, the C. trachomatis organisms may have to spread from cell to cell, which inevitably exposes the organisms to extracellular mucosal effectors such as complement factors that are known to possess strong antichlamydial activities. Here, we report that the chlamydia-secreted protease CPAF efficiently neutralized complement factor C3-dependent antichlamydial activity. The neutralization was dependent on the proteolytic activity of CPAF and correlated with the CPAF-mediated degradation of complement factor C3 and factor B. As a result, CPAF preferentially inhibited the alternative complement activation pathway. The significance and limitation of these observations were discussed.

Quantifying promoter activity during the developmental cycle of Chlamydia trachomatis.

Chlamydia trachomatis is an important human pathogen that undergoes a characteristic development cycle correlating with stage-specific gene expression profiles. Taking advantage of recent developments in the genetic transformation in C. trachomatis, we constructed a versatile green fluorescent protein (GFP) reporter system to study the development-dependent function of C. trachomatis promoters in an attempt to elucidate the mechanism that controls C. trachomatis adaptability. We validated the use of the GFP reporter system by visualizing the activity of an early euo gene promoter. Additionally, we uncovered a new ompA promoter, which we named P3, utilizing the GFP reporter system combined with 5′ rapid amplification of cDNA ends (RACE), in vitro transcription assays, real-time quantitative RT-PCR (RT-qPCR), and flow cytometry. Mutagenesis of the P3 region verifies that P3 is a new class of C. trachomatis σ66-dependent promoter, which requires an extended −10 TGn motif for transcription. These results corroborate complex developmentally controlled ompA expression in C. trachomatis. The exploitation of genetically labeled C. trachomatis organisms with P3-driven GFP allows for the observation of changes in ompA expression in response to developmental signals. The results of this study could be used to complement previous findings and to advance understanding of C. trachomatis genetic expression.

Sensitivity of the Standard Chlamydia trachomatis Culture Method Is Improved After One Additional In Vitro Passage.

Chlamydia trachomatis causes the most common bacterial sexually transmitted infection (STI) worldwide. Although highly sensitive nucleic acid amplification tests (NAATs) are used to routinely diagnose chlamydial infection, C. trachomatis isolation by cell culture is still preferred for legal cases and epidemiological studies because of its high specificity; however, the sensitivity of traditional two-passage diagnostic cultures is significantly lower than that of NAATs. Therefore, we sought to analyze if additional in vitro passaging of clinical samples would improve detection sensitivity of C. trachomatis. Clinical swabs (n = 428) were collected from Tianjin Medical University General Hospital, grown in McCoy cells for up to five passages, and analyzed for the presence of inclusions by iodine staining. Results were confirmed by routine PCR-based methods. Viable C. trachomatis organisms were detected in 91 (21.26%) swabs with the traditional two-passage protocol, which increased to 145 (33.88%) and 149 (34.81%) following three and four passages, respectively. Thus, the standard protocol yielded a false-negative rate of nearly 39%. Subsequent PCR-based diagnostics revealed a concordance rate of 80.98% between these two methods without any false negatives. The results of this study support the use of a three-passage Chlamydia culture procedure to increase the detection sensitivity of this method.

Chlamydia-secreted protease CPAF degrades host antimicrobial peptides

Chlamydia trachomatis infection in the lower genital tract, if untreated, can ascend to the upper genital tract, potentially leading to complications such as tubal factor infertility. The ascension involves cell-to-cell spreading, which may require C. trachomatis organisms to overcome mucosal extracellular effectors such as antimicrobial peptides. We found that among the 8 antimicrobial peptides tested, the cathelicidin LL-37 that is produced by both urogenital epithelial cells and the recruited neutrophils possessed a most potent antichlamydial activity. Interestingly, this antichlamydial activity was completely inhibited by CPAF, a C. trachomatis-secreted serine protease. The inhibition was dependent on CPAF's proteolytic activity. CPAF selectively degraded LL-37 and other antimicrobial peptides with an antichlamydial activity. CPAF is known to secrete into and accumulate in the infected host cell cytoplasm at the late stage of chlamydial intracellular growth and may be released to confront the extracellular antimicrobial peptides before the intra-inclusion organisms are exposed to extracellular environments during host cell lysis and chlamydial spreading. Thus, the finding that CPAF selectively targets host antimicrobial peptides that possess antichlamydial activities for proteolysis suggests that CPAF may contribute to C. trachomatis pathogenicity by aiding in ascending infection.

Detection of Chlamydia Trachomatis in Patients with Unexplained Infertility : A Case Control Study

Our Objective: is to detect Chlamydia Trachomatis organism in cervical swabs obtained frompatients with unexplained infertility(UI) and to compare its incidence in infertile compared to fertile females in reproductive age. The study design was a case control observational study, done in Cairo University Hospitals. Methodology: One hundred females diagnosed as unexplained infertility and 100 normal fertile females were included in the study for detection of Chlamydia trachomatis by using polymerase chain reaction (PCR) of cervical swab samples. Results: Fifteen females were positive for Chlamydia trachomatis in infertile group while only 2were positive in healthy fertile group with p value of 0.002. Conclusion: The Incidence of Chlamydia trachomatis in cervical swabs was significantly higher in unexplained infertile females compared with the control group

The Epidemiology of Chlamydia trachomatis Organism Load During Genital Infection: A Systematic Review.

The role of organism load in Chlamydia trachomatis infection is not well understood. We conducted a systematic review to investigate the epidemiology of C. trachomatis organism load in human genital chlamydia infection. Embase, PubMed, and Medline databases were searched for literature published through August 2014. English-language publications that quantified load in humans were eligible. Participant characteristics and laboratory data were extracted. A total of 737 records were identified, and 29 publications involving 40 883 participants were included. In women, load was highest for cervical swabs and lowest for urine specimens. In men, load was highest for rectal swabs and similar for urethral swabs and urine specimens. Evidence of any association between load and age, serovar, risk of transmission, hormone levels, and concurrent sexually transmitted infections was inconsistent. Eight of 9 culture-based studies found an association between load and signs and symptoms, in contrast with only 3 of 8 nucleic acid amplification test (NAAT)-based studies (P = .03). Chlamydia organism load varies by specimen type and site of sampling, and viable chlamydia organism load may be a more important indicator of severity of infection than total load measured by NAAT.

A mouse model for Chlamydia suis genital infection.

A mouse model for Chlamydia suis genital infection was developed. Ninety-nine mice were randomly divided into three groups and intravaginally inoculated with chlamydia: 45 mice (group 1) received C. suis purified elementary bodies (EBs), 27 (group 2) were inoculated with C. trachomatis genotype E EBs and 27 mice (group 3) with C. trachomatis genotype F EBs. Additionally, 10 mice were used as a negative control. At seven days post-infection (dpi) secretory anti-C. suis IgA were recovered from vaginal swabs of all C. suis inoculated mice. Chlamydia suis was isolated from 93, 84, 71 and 33% vaginal swabs at 3, 5, 7 and 12 dpi. Chlamydia trachomatis genotype E and F were isolated from 100% vaginal swabs up to 7 dpi and from 61 and 72%, respectively, at 12 dpi. Viable C. suis and C. trachomatis organisms were isolated from uterus and tubes up to 16 and 28 dpi, respectively. The results of the present study show the susceptibility of mice to intravaginal inoculation with C. suis. A more rapid course and resolution of C. suis infection, in comparison to C. trachomatis, was highlighted. The mouse model could be useful for comparative investigations involving C. suis and C. trachomatis species.

Transcriptional profiling of human epithelial cells infected with plasmid-bearing and plasmid-deficient Chlamydia trachomatis.

Chlamydia trachomatis is an obligate intracellular epitheliotropic bacterial pathogen of humans. Infection of the eye can result in trachoma, the leading cause of preventable blindness in the world. The pathophysiology of blinding trachoma is driven by multiple episodes of reinfection of conjunctival epithelial cells, producing an intense chronic inflammatory response resulting in submucosal tissue remodeling and scarring. Recent reports have shown that infection with trachoma organisms lacking the cryptic chlamydial plasmid is highly attenuated in macaque eyes, a relevant experimental model of human trachoma infection. To better understand the molecular basis of plasmid-mediated infection attenuation and the potential modulation of host immunity, we conducted transcriptional profiling of human epithelial cells infected with C. trachomatis plasmid-bearing (A2497) and plasmid-deficient (A2497P(-)) organisms. Infection of human epithelial cells with either strain increased the expression of host genes coding for proinflammatory (granulocyte-macrophage colony-stimulating factor [GM-CSF], macrophage colony-stimulating factor [MCSF], interleukin-6 [IL-6], IL-8, IL-1α, CXCL1, CXCL2, CXCL3, intercellular adhesion molecule 1 [ICAM1]), chemoattraction (CCL20, CCL5, CXCL10), immune suppression (PD-L1, NFKB1B, TNFAIP3, CGB), apoptosis (CASP9, FAS, IL-24), and cell growth and fibrosis (EGR1 and IL-20) proteins. Statistically significant increases in the levels of expression of many of these genes were found in A2497-infected cells compared to the levels of expression in A2497P(-)-infected cells. Our findings suggest that the chlamydial plasmid plays a focal role in the host cell inflammatory response to infection and immune avoidance. These results provide new insights into the role of the chlamydial plasmid as a chlamydial virulence factor and its contributions to trachoma pathogenesis.

Chlamydia trachomatis GlgA Is Secreted into Host Cell Cytoplasm

Glycogen has been localized both inside and outside Chlamydia trachomatis organisms. We now report that C. trachomatis glycogen synthase (GlgA) was detected in both chlamydial organism-associated and -free forms. The organism-free GlgA molecules were localized both in the lumen of chlamydial inclusions and in the cytosol of host cells. The cytosolic GlgA displayed a distribution pattern similar to that of a known C. trachomatis-secreted protease, CPAF. The detection of GlgA was specific since the anti-GlgA antibody labeling was only removed by preabsorption with GlgA but not CPAF fusion proteins. GlgA was detectable at 12h and its localization into host cell cytosol only became apparent at 24h after infection. The cytosolic localization of GlgA was conserved among all C. trachomatis serovars. However, the significance of the GlgA secretion into host cell cytoplasm remains unclear since, while expression of chlamydial GlgA in HeLa cells increased glycogen stores, it did not affect a subsequent infection with C. trachomatis. Similar to several other C. trachomatis-secreted proteins, GlgA is immunogenic in women urogenitally infected with C. trachomatis, suggesting that GlgA is expressed and may be secreted into host cell cytosol during C. trachomatis infection in humans. These findings have provided important information for further understanding C. trachomatis pathogenic mechanisms.

T cell correlates of solid protective immunity following immunization of macaques with a live-attenuated trachoma vaccine (P4403)

Abstract Trachoma, caused by Chlamydia trachomatis, is the world’s leading cause of preventable blindness for which a vaccine is needed. We previously described a live-attenuated trachoma vaccine (LATV) in non-human primates (Kari L. 2011 JEM 208: 2217-23). Vaccinated macaques were either solidly or partially protected following challenge with virulent trachoma organisms. Our current goal was to characterize immune responses that correlated with solid protective immunity. Here, we preformed intramuscular boosting of LATV vaccinated macaques and studied the T cell recall response in PBMC by flow cytometry. Both solidly and partially protected macaques exhibited a strong PBMC CD8+ T recall response following intramuscular immunization. Notably, however; only CD8+ T cells from solidly protected macaques strongly proliferated in response to chlamydial soluble antigen (SA) prepared from chlamydial infected cells. The SA contained proteins known to be secreted by chlamydiae into the host cytosol making them logical antigenic targets of cytotoxic CD8+ T cells. The SA expanded CD8+ T cells expressed IFN-γ, granzyme B, and α4β7 integrin implicating them as effectors important to the development of solid protective immunity at the ocular mucosae. Identifying the effector function and antigens recognized by these CD8+ T cells will be the focus of future studies as this information will provide insights into the design of more conventional immunotherapeutic approaches for trachoma control.

Isolation of Chlamydia trachomatis and membrane vesicles derived from host and bacteria

The study of intracellular bacteria and nanometer-size membrane vesicles within infected host cells poses an important challenge as it is difficult to identify each distinct population in the context of the complex populations generated from active host-pathogen interactions. Here, suspension cultures of L929 cells infected with the prevalent obligate intracellular bacterium Chlamydia trachomatis strain F/Cal-IC-13 are utilized for the large scale preparation and isolation of natural membrane vesicles and bacterial forms. Cell lysis with nitrogen cavitation in combination with differential centrifugation, OptiPrep™ density gradient separation, and immunoenrichment using anti-chlamydial lipopolysaccharide antibodies and MagnaBind beads allows for the isolation of both productive and persistent bacterial forms, as well as membrane vesicles derived from the host and pathogen. We have evaluated these populations by electron microscopy and Western blot analysis for identification of biomarkers. In addition, purified persistent forms of C. trachomatis induced by ampicillin display adenosine-5′-triphosphate (ATP) transport activity, suggesting that ampicillin-induced persistent C. trachomatis organisms, at least in part, rely upon host ATP as an energy source. Importantly, several chlamydial cytotoxic and/or secreted proteins are demonstrated to be associated with these vesicles, supporting the idea that membrane vesicles are generated by Chlamydia as a means of carrying and delivering virulence factors necessary for pathogenesis. The ability to produce large-scale infections and generate distinct bacteria and host-derived populations for biochemical analysis, while reducing the burdens of time and cost have implications in all areas of chlamydiology. These protocols can be applied to other strains of C. trachomatis or other intracellular bacteria.

Difficulties experienced in defining the microbial cause of pelvic inflammatory disease

Clinical assessment of women with pelvic pain was a poor indicator of disease seen at laparoscopy. Thus, of 109 women, 22 at laparoscopy had salpingitis, 19 had adhesions without salpingitis, 20 had endometriosis or ovarian pathology and 48 no observable abnormality. In all laparoscopic categories, Ureaplasma spp. and Mycoplasma hominis, but not Mycoplasma genitalium, were at least as common in the cervix/vagina as Chlamydia trachomatis and equally frequent in the endometrium. However, C. trachomatis had the greatest propensity for spread to the Fallopian tubes. Thus, of 28 women who had C. trachomatis organisms in the vagina/cervix, 13 had them in a Fallopian tube (ratio 2.2:1); the ratio was 6:1 for Neisseria gonorrhoeae, 8:1 for M. genitalium, 21:1 for M. hominis and 31:1 for Ureaplasma spp. M. hominis organisms in a large number were detected most often in women with salpingitis. The likelihood of spread of Ureaplasma urealyticum and U. parvum from the lower to the upper genital tract was about the same and they were detected only once each in a tube, which was not inflamed in either case. Multiple bacteria were often detected at a single site, making it difficult to establish the exact cause of disease. However N. gonorrhoeae was considered to be the sole cause of salpingitis in one woman and the primary or equal primary contributor in four others; C. trachomatis was involved in at least 11 women, mostly as the sole cause or as the primary contributor; M. genitalium was considered the cause in one woman and had possible involvement in three others; and M. hominis was a questionable sole cause in one woman and the primary or equal primary contributor in three. Serologically, C. trachomatis was related to adhesions, without salpingitis, more often (63%) than any other micro-organism. M. genitalium may have been implicated in one case. Serologically, a previous C. trachomatis infection was indicated in 40% of women without an observable laparoscopic abnormality. C. trachomatis in the endometrium and tubes of women without any laparoscopic abnormality suggests subclinical disease, endometritis or endosalpingitis. There was evidence for a smaller proportion (19%) of women without an abnormality having been infected previously with M. genitalium. To some extent this is consistent with the infrequency of acute M. genitalium infections in this cohort of women.

Enhanced upper genital tract pathologies by blocking Tim-3 and PD-L1 signaling pathways in mice intravaginally infected with Chlamydia muridarum

BackgroundAlthough Tim-3 & PD-L1 signaling pathways play important roles in negatively regulating immune responses, their roles in chlamydial infection have not been evaluated.MethodsNeutralization antibodies targeting Tim-3 and PD-L1 were used to treat mice. Following an intravaginal infection with C. muridarum organisms, mice with or without the dual antibody treatment were compared for live chlamydial organism shedding from the lower genital tract and inflammatory pathology in the upper genital tract.ResultsMice treated with anti-Tim-3 and anti-PD-L1 antibodies displayed a time course of live organism shedding similar to that of mice treated with equivalent amounts of isotype-matched IgG molecules. The combined antibody blocking failed to alter either the lower genital tract cytokine or systemic humoral and cellular adaptive responses to C. muridarum infection. However, the antibody blocking significantly enhanced C. muridarum-induced pathologies in the upper genital tract, including more significant hydrosalpinx and inflammatory infiltration in uterine horn and oviduct tissues.ConclusionsThe Tim-3 and PD-L1-mediated signaling can significantly reduce pathologies in the upper genital tract without suppressing immunity against chlamydial infection, suggesting that Tim-3 and PD-L1-mediated negative regulation may be manipulated to attenuate tubal pathologies in women persistently infected with C. trachomatis organisms.

Protective immunity against mouse upper genital tract pathology correlates with high IFNγ but low IL-17 T cell and anti-secretion protein antibody responses induced by replicating chlamydial organisms in the airway

To search for optimal immunization conditions for inducing protective immunity against upper genital tract pathologies caused by chlamydial intravaginal infection, we compared protection efficacy in mice immunized intranasally or intramuscularly with live or inactivated Chlamydia muridarum organisms. Mice immunized intranasally with live organisms developed strong protection against both vaginal shedding of infectious organisms and upper genital tract pathologies. The protection correlated with a robust antigen-specific T cell response with high IFNγ but low IL-17. Although a significant level of IL-5 was also detected, these mice maintained an overall Th1-dorminant immunity following immunization and challenge infection. On the contrary, mice immunized intranasally with inactivated organisms or intramuscularly with live or inactivated organisms produced high levels of IL-17 and still developed significant upper genital tract pathologies. High titers of antibodies against chlamydial secretion antigens were detected only in mice immunized intranasally with live organisms but not mice in other groups, suggesting that the intranasally inoculated live organisms were able to undergo replication and immune responses to the chlamydial secretion proteins may contribute to protective immunity. These observations have provided important information on how to develop subunit vaccines for inducing protective immunity against urogenital infection with Chlamydia trachomatis organisms.

Infectious Chlamydia pneumoniae is Associated With Elevated Interleukin-8 and Airway Neutrophilia in Children With Refractory Asthma

Neutrophilic asthma is thought to be less responsive than eosinophilic asthma to anti-inflammatory therapies including corticosteroids. Chlamydia pneumoniae has been implicated in asthma, possibly by induction of interleukin (IL-8). We hypothesized that IL-8 is increased in the bronchoalveolar lavage (BAL) fluid from children with asthma and C. pneumoniae. BAL fluid was analyzed for C. pneumoniae and IL-8 using polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay from 2 asthma patient populations in the Bronx, NY and Massachusetts with an average age of 8 and 8.7 years old, respectively. For comparison, samples were also analyzed for C. trachomatis and Mycoplasma 16s DNA. Of 18 Bronx samples analyzed, 6 (33%) were PCR-positive for C. pneumoniae, 10 (56%) for C. trachomatis, and 8 (44%) for Mycoplasma 16s DNA. IL-8 from C. pneumoniae-positive samples was 3.3-fold higher compared with negative samples (P = 0.003). There was no difference between patients tested for C. trachomatis or Mycoplasma. Of 84 Massachusetts samples analyzed, 42 (50%) were PCR-positive for C. pneumoniae, 42 (50%) for C. trachomatis, and 13 (16%) for Mycoplasma. IL-8 concentration from C. pneumoniae-positive samples was 10.49-fold higher compared with negative samples (P = 0.0001). As in the Bronx cohort, there were no differences between patients tested for C. trachomatis or Mycoplasma. Lastly, BAL neutrophilia predicted the presence of C. pneumoniae but not Mycoplasma or C. trachomatis. Children with asthma who were PCR-positive for C. pneumoniae demonstrated elevated concentrations of IL-8 and neutrophils in BAL fluid compared with similar patients who were positive for C. trachomatis or Mycoplasma organisms, but PCR-negative for C. pneumoniae. Undiagnosed C. pneumoniae infection in children may therefore contribute to poorly controlled asthma via induction of IL-8.

Association of tubal factor infertility with elevated antibodies to Chlamydia trachomatis caseinolytic protease P

The objective of the study was to assess antibodies against Chlamydia trachomatis heat shock proteins (HSP) in patients with tubal factor infertility (TFI), infertility controls (IFC), and fertile controls (FC). HSPs assist organisms in surviving caustic environments such as heat. Twenty-one TFI, 15 IFC, and 29 FC patients were enrolled after laparoscopic tubal assessment. The titers of antibodies against C trachomatis organisms and 14 chlamydial HSPs were compared among the 3 groups. TFI patients developed significantly higher levels of antibodies against C trachomatis and specifically recognizing chlamydial HSP60 and caseinolytic protease (Clp) P, a subunit of the ATP-dependent Clp protease complex involved in the degradation of abnormal proteins. In addition to confirming high titers of antibodies against C trachomatis organisms and HSP60 in TFI patients, we identified a novel link of TFI with anti-ClpP antibodies. These findings may provide useful information for developing a noninvasive screening test for TFI and constructing subunit anti-C trachomatis vaccines.