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1.
Immunity ; 49(5): 873-885.e7, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30366765

RESUMO

Receptor interacting protein 2 (RIP2) plays a role in sensing intracellular pathogens, but its function in T cells is unclear. We show that RIP2 deficiency in CD4+ T cells resulted in chronic and severe interleukin-17A-mediated inflammation during Chlamydia pneumoniae lung infection, increased T helper 17 (Th17) cell formation in lungs of infected mice, accelerated atherosclerosis, and more severe experimental autoimmune encephalomyelitis. While RIP2 deficiency resulted in reduced conventional Th17 cell differentiation, it led to significantly enhanced differentiation of pathogenic (p)Th17 cells, which was dependent on RORα transcription factor and interleukin-1 but independent of nucleotide oligomerization domain (NOD) 1 and 2. Overexpression of RIP2 resulted in suppression of pTh17 cell differentiation, an effect mediated by its CARD domain, and phenocopied by a cell-permeable RIP2 CARD peptide. Our data suggest that RIP2 has a T cell-intrinsic role in determining the balance between homeostatic and pathogenic Th17 cell responses.


Assuntos
Diferenciação Celular/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Células Th17/citologia , Células Th17/metabolismo , Animais , Aterosclerose , Biomarcadores , Domínio de Ativação e Recrutamento de Caspases , Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/mortalidade , Expressão Gênica , Imunofenotipagem , Inflamação/genética , Inflamação/metabolismo , Interleucina-17/biossíntese , Interleucina-1beta , Camundongos , Camundongos Knockout , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor , Proteína Serina-Treonina Quinases de Interação com Receptores/química , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(20): e2303487120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155906

RESUMO

The centrosome is the main microtubule organizing center of the cell and is crucial for mitotic spindle assembly, chromosome segregation, and cell division. Centrosome duplication is tightly controlled, yet several pathogens, most notably oncogenic viruses, perturb this process leading to increased centrosome numbers. Infection by the obligate intracellular bacterium Chlamydia trachomatis (C.t.) correlates with blocked cytokinesis, supernumerary centrosomes, and multipolar spindles; however, the mechanisms behind how C.t. induces these cellular abnormalities remain largely unknown. Here we show that the secreted effector protein, CteG, binds to centrin-2 (CETN2), a key structural component of centrosomes and regulator of centriole duplication. Our data indicate that both CteG and CETN2 are necessary for infection-induced centrosome amplification, in a manner that requires the C-terminus of CteG. Strikingly, CteG is important for in vivo infection and growth in primary cervical cells but is dispensable for growth in immortalized cells, highlighting the importance of this effector protein to chlamydial infection. These findings begin to provide mechanistic insight into how C.t. induces cellular abnormalities during infection, but also indicate that obligate intracellular bacteria may contribute to cellular transformation events. Centrosome amplification mediated by CteG-CETN2 interactions may explain why chlamydial infection leads to an increased risk of cervical or ovarian cancer.


Assuntos
Centrossomo , Chlamydia trachomatis , Feminino , Humanos , Centrossomo/metabolismo , Divisão Celular , Segregação de Cromossomos , Colo do Útero , Fuso Acromático/metabolismo
3.
J Biol Chem ; 300(6): 107350, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718865

RESUMO

The obligate intracellular bacterium, Chlamydia trachomatis, has evolved to depend on its human host for many metabolites, including most amino acids and three of the four nucleotides. Given this, it is not surprising that depletion of a single amino acid in the host cell growth medium blocks chlamydial replication. Paradoxically, supra-normal levels of some amino acids also block productive replication of Chlamydia. Here, we have determined how elevated serine levels, generated by exogenous supplementation, impede chlamydial inclusion development and reduce the generation of infectious progeny. Our findings reveal that human serine racemase, which is broadly expressed in multiple tissues, potentiates the anti-chlamydial effect of elevated serine concentrations. In addition to reversibly converting l-serine to d-serine, serine racemase also deaminates serine via ß-elimination. We have determined that d-serine does not directly impact Chlamydia; rather, ammonia generated by serine deamination limits the productive chlamydial replication. Our findings imply that ammonia produced within host cells can traverse the chlamydial inclusion membrane. Further, this property of serine deaminase can be exploited to sensitize Chlamydia to concentrations of doxycycline that are otherwise not bactericidal. Because exogenously elevated levels of serine can be tolerated over extended periods, the broad expression pattern of serine racemase indicates it to be a host enzyme whose activity can be directed against multiple intracellular bacterial pathogens. From a therapeutic perspective, demonstrating host metabolism can be skewed to generate an anti-bacterial metabolite that synergizes with antibiotics, we believe our results provide a new approach to target intracellular pathogens.


Assuntos
Antibacterianos , Chlamydia trachomatis , Serina , Humanos , Chlamydia trachomatis/metabolismo , Chlamydia trachomatis/efeitos dos fármacos , Serina/metabolismo , Antibacterianos/farmacologia , Células HeLa , Racemases e Epimerases/metabolismo , Desaminação , Infecções por Chlamydia/metabolismo , Infecções por Chlamydia/tratamento farmacológico , Infecções por Chlamydia/microbiologia
4.
Proc Natl Acad Sci U S A ; 119(36): e2205856119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037367

RESUMO

Protists are important regulators of microbial communities and key components in food webs with impact on nutrient cycling and ecosystem functioning. In turn, their activity is shaped by diverse intracellular parasites, including bacterial symbionts and viruses. Yet, bacteria-virus interactions within protists are poorly understood. Here, we studied the role of bacterial symbionts of free-living amoebae in the establishment of infections with nucleocytoplasmic large DNA viruses (Nucleocytoviricota). To investigate these interactions in a system that would also be relevant in nature, we first isolated and characterized a giant virus (Viennavirus, family Marseilleviridae) and a sympatric potential Acanthamoeba host infected with bacterial symbionts. Subsequently, coinfection experiments were carried out, using the fresh environmental isolates as well as additional amoeba laboratory strains. Employing fluorescence in situ hybridization and qPCR, we show that the bacterial symbiont, identified as Parachlamydia acanthamoebae, represses the replication of the sympatric Viennavirus in both recent environmental isolates as well as Acanthamoeba laboratory strains. In the presence of the symbiont, virions are still taken up, but viral factory maturation is inhibited, leading to survival of the amoeba host. The symbiont also suppressed the replication of the more complex Acanthamoeba polyphaga mimivirus and Tupanvirus deep ocean (Mimiviridae). Our work provides an example of an intracellular bacterial symbiont protecting a protist host against virus infections. The impact of virus-symbiont interactions on microbial population dynamics and eventually ecosystem processes requires further attention.


Assuntos
Amoeba , Vírus Gigantes , Mimiviridae , Simbiose , Amoeba/microbiologia , Amoeba/virologia , Ecossistema , Vírus Gigantes/genética , Hibridização in Situ Fluorescente , Mimiviridae/genética
5.
J Infect Dis ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394609

RESUMO

BACKGROUND: Chlamydia trachomatis (CT) testing and treatment strategies have not decreased infection rates, justifying need for a CT vaccine. A murine study showed that a vaccine consisting of MOMP and 4 polymorphic membrane proteins (Pmps E, F, G, H) elicited protective immunity; studies on human cellular immune responses to Pmps are sparse. METHODS: Interferon gamma (IFN-γ) responses to these 5 CT proteins were measured by ELISPOT in PBMCs from women returning for treatment of a positive CT screening test. Responses were compared in those with spontaneous CT clearance vs. persisting infection at baseline and no reinfection vs. reinfection at a 3-month follow-up visit. RESULTS: IFN-γ response to one or more proteins was detected in 39% at baseline and 51.5% at follow-up; PmpE and MOMP most often elicited positive responses. IFN-γ responses to MOMP were detected less often at follow-up vs. baseline in women with reinfection, but were maintained in those without reinfection. Women with spontaneous clearance had a higher magnitude of IFN-γ response to PmpE and MOMP. CONCLUSIONS: IFN-γ responses to these 5 CT vaccine candidate proteins were heterogenous and primarily directed against MOMP and PmpE. Spontaneous clearance of infection and absence of reinfection may be clinical correlates of protection.

6.
J Infect Dis ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640957

RESUMO

Chlamydia trachomatis (CT) is a sexually transmitted infection that can lead to adverse reproductive health outcomes. CT prevalence estimates are primarily derived from screening using nucleic acid amplification tests (NAATs). However, screening guidelines in the United States only include particular subpopulations, and NAATs only detect current infections. In contrast, seroassays identify past CT infections which are important for understanding the public health impacts of CT, including pelvic inflammatory disease and tubal factor infertility. Older seroassays have been plagued by low sensitivity and specificity and have not been validated using a consistent reference measure, making it challenging to compare studies, define the epidemiology of CT and determine the effectiveness of control programs. Newer seroassays have better performance characteristics. This narrative review summarizes the "state of the science" for CT seroassays that have been applied in epidemiologic studies and provides practical considerations for interpreting the literature and employing seroassays in future research.

7.
J Infect Dis ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38723186

RESUMO

Targeted therapy is an attractive approach for treating infectious diseases. Affibody molecules have similar capability to antibodies that facilitate molecular recognition in both diagnostic and therapeutic applications. Targeting major outer membrane protein (MOMP) for treating infection of Chlamydia trachomatis, one of the most common sexually transmitted pathogens, is a promising therapeutic approach. Previously, we have reported a MOMP-specific affibody (ZMOMP:461) from phage display library. Here, we first fused it with modified Pseudomonas Exotoxin (PE38KDEL) and a cell-penetrating peptide (CPP) to develop an affitoxin, Z461X-CPP. We then verified the addition of both toxin and CPPs that did not affect the affinitive capability of ZMOMP:461 to MOMP. Upon uptake by C.trachomatis-infected cells, Z461X-CPP induced cell apoptosis in vitro. In animal model, Z461X significantly shortened the duration of C. trachomatis infection and prevented pathological damage in mouse reproductive system. These findings provide compelling evidence that the MOMP-specific affitoxin has great potential for targeting therapy of C. trachomatis infection.

8.
J Infect Dis ; 229(3): 845-854, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-37584273

RESUMO

BACKGROUND: Neisseria gonorrheae and Chlamydia trachomatis are associated with mucosal inflammation and human immunodeficiency virus 1 (HIV-1) transmission. We assessed levels of inflammatory cytokines in men who have sex with men (MSM) with and without rectal gonorrhea and/or chlamydia in Lima, Peru. METHODS: We screened 605 MSM reporting condomless receptive anal intercourse for rectal N. gonorrheae/C. trachomatis using nucleic acid testing. We identified 101 cases of gonorrhea and/or chlamydia and randomly selected 50 N. gonorrheae/C. trachomatis positive cases and matched 52 negative controls. We measured levels of IL-1ß, IL-6, IL-8, and TNF-α in rectal secretions. Tests for HIV-1, rectal N. gonorrheae/C. trachomatis, and mucosal cytokines were repeated after 3 and 6 months. Cytokine levels in cases and uninfected controls were compared using Wilcoxon rank-sum tests and linear regression. RESULTS: MSM with gonorrhea/chlamydia had elevated levels of all cytokines in rectal mucosa compared with matched controls (all P values <.001). Following antibiotic treatment there were no significant differences in cytokine levels at 3- or 6-month follow-up evaluations (all P values >.05). DISCUSSION: Rectal gonorrhea/chlamydia infection is associated with transient mucosal inflammation and cytokine recruitment. Our data provide proof of concept for rectal sexually transmitted infection screening as an HIV prevention strategy for MSM. Clinical Trials Registration. NCT03010020.


Assuntos
Infecções por Chlamydia , Gonorreia , Infecções por HIV , HIV-1 , Doenças Retais , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Gonorreia/diagnóstico , Chlamydia trachomatis , Citocinas , Peru/epidemiologia , Neisseria gonorrhoeae , Infecções por Chlamydia/diagnóstico , Doenças Retais/epidemiologia , Mucosa , Inflamação , Infecções por HIV/tratamento farmacológico , Prevalência
9.
J Infect Dis ; 229(6): 1637-1647, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38147361

RESUMO

BACKGROUND: The pathogenesis of Chlamydia trachomatis is associated with the induction of the host inflammatory response; however, the precise underlying molecular mechanisms remain poorly understood. METHODS: CT622, a T3SS effector protein, has an important role in the pathogenesis of C trachomatis; however, whether CT622 can induce a host inflammatory response is not understood. Our findings demonstrate that CT622 induces the expression of interleukins 6 and 8 (IL-6 and IL-8). Mechanistically, these effects involve the activation of the MAPK/NF-κB signaling pathways (mitogen-activated protein kinase/nuclear factor κB). RESULTS: Interestingly, we demonstrated that the suppression of toll-like receptor 4 using small interfering RNA markedly reduced the phosphorylation of ERK, p38, JNK, and IκBα, concomitant with a significant decrease in IL-6 and IL-8 secretion. Conversely, disruption of toll-like receptor 2 abrogated the CT622-induced upregulation of IL-8 and activation of ERK, whereas IL-6 expression and p38, JNK, and IκBα phosphorylation were unaffected. CONCLUSIONS: Taken together, these results indicate that CT622 contributes to the inflammatory response through the toll-like receptor 2/4-mediated MAPK/NF-κB pathways, which provides insight into the molecular pathology of C trachomatis infection.


Assuntos
Chlamydia trachomatis , Citocinas , NF-kappa B , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Humanos , Chlamydia trachomatis/imunologia , NF-kappa B/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Células THP-1 , Citocinas/metabolismo , Transdução de Sinais , Interleucina-6/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Infecções por Chlamydia/imunologia , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/metabolismo , Interleucina-8/metabolismo , Sistemas de Secreção Tipo III/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases , Fosforilação
10.
J Infect Dis ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547503

RESUMO

BACKGROUND: Chlamydia trachomatis is the causative agent of most prevalent bacterial sexually transmitted infection globally. Whole-genome sequencing is essential for molecular Chlamydia surveillance; however, its application is hampered by the pathogen's low abundance in clinical specimens and the expensive, labor-intensive nature of existing enrichment methodologies for Chlamydia. METHODS: We developed a targeted whole-genome amplification tool termed SWTICH, by integrating phi29 DNA polymerase-mediated amplification with meticulously designed primer sets to enrich Chlamydia trachomatis genome, followed by whole-genome sequencing. This method underwent evaluation through testing synthetic and clinical specimens. RESULTS: SWITCH demonstrated robust ability to achieve up to 98.3% genomic coverage of Chlamydia trachomatis from as few as 26.4 genomic copies present in synthetic specimens and exhibited excellent performance across diverse Chlamydia trachomatis serovars. Utilizing SWITCH, we directly generated 21 Chlamydia genomes from 26 clinical samples, enabling us to gain insights into the genetic relationships and phylogeny of current Chlamydia strains circulating in the country. Remarkably, this study marked the first instance of generating Chinese Chlamydia genomes directly from clinical samples. CONCLUSIONS: SWITCH represents a practical, cost-efficient approach to enrich Chlamydia genome directly from clinical specimens, offering an efficient avenue for molecular surveillance of Chlamydia.

11.
J Biol Chem ; 299(1): 102762, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463962

RESUMO

Chlamydia trachomatis (ct) is the most reported bacterial sexually transmitted infection worldwide and the leading cause of preventable blindness. Caseinolytic proteases (ClpP) from pathogenic bacteria are attractive antibiotic targets, particularly for bacterial species that form persister colonies with phenotypic resistance against common antibiotics. ClpP functions as a multisubunit proteolytic complex, and bacteria are eradicated when ClpP is disrupted. Although crucial for chlamydial development and the design of agents to treat chlamydia, the structures of ctClpP1 and ctClpP2 have yet to be solved. Here, we report the first crystal structure of full-length ClpP2 as an inactive homotetradecamer in a complex with a candidate antibiotic at 2.66 Å resolution. The structure details the functional domains of the ClpP2 protein subunit and includes the handle domain, which is integral to proteolytic activation. In addition, hydrogen-deuterium exchange mass spectroscopy probed the dynamics of ClpP2, and molecular modeling of ClpP1 predicted an assembly with ClpP2. By leveraging previous enzymatic experiments, we constructed a model of ClpP2 activation and its interaction with the protease subunits ClpP1 and ClpX. The structural information presented will be relevant for future rational drug design against these targets and will lead to a better understanding of ClpP complex formation and activation within this important human pathogen.


Assuntos
Chlamydia trachomatis , Endopeptidase Clp , Modelos Moleculares , Humanos , Antibacterianos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Chlamydia trachomatis/enzimologia , Endopeptidase Clp/química , Endopeptidase Clp/metabolismo , Cristalização , Domínios Proteicos
12.
Infect Immun ; 92(3): e0053923, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38299827

RESUMO

The obligate intracellular bacterium Chlamydia has a unique developmental cycle that alternates between two contrasting cell types. With a hardy envelope and highly condensed genome, the small elementary body (EB) maintains limited metabolic activities yet survives in extracellular environments and is infectious. After entering host cells, EBs differentiate into larger and proliferating reticulate bodies (RBs). Progeny EBs are derived from RBs in late developmental stages and eventually exit host cells. How expression of the chlamydial genome consisting of nearly 1,000 genes governs the chlamydial developmental cycle is unclear. A previous microarray study identified only 29 Chlamydia trachomatis immediate early genes, defined as genes with increased expression during the first hour postinoculation in cultured cells. In this study, we performed more sensitive RNA sequencing (RNA-Seq) analysis for C. trachomatis cultures with high multiplicities of infection. Remarkably, we observed well over 700 C. trachomatis genes that underwent 2- to 900-fold activation within 1 hour postinoculation. Quantitative reverse transcription real-time PCR analysis was further used to validate the activated expression of a large subset of the genes identified by RNA-Seq. Importantly, our results demonstrate that the immediate early transcriptome is over 20 times more extensive than previously realized. Gene ontology analysis indicates that the activated expression spans all functional categories. We conclude that over 70% of C. trachomatis genes are activated in EBs almost immediately upon entry into host cells, thus implicating their importance in initiating rapid differentiation into RBs and establishing an intracellular niche conducive with chlamydial development and growth.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Humanos , Células Cultivadas , Sequência de Bases , Transcriptoma , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Chlamydia/genética
13.
Infect Immun ; : e0006324, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899879

RESUMO

Toll-like receptor 9 (TLR9) is an innate immune receptor that localizes to endosomes in antigen presenting cells and recognizes single stranded unmethylated CpG sites on bacterial genomic DNA (gDNA). Previous bioinformatic studies have demonstrated that the genome of the human pathogen Chlamydia trachomatis contains TLR9 stimulatory motifs, and correlative studies have implied a link between human TLR9 (hTLR9) genotype variants and susceptibility to infection. Here, we present our evaluation of the stimulatory potential of C. trachomatis gDNA and its recognition by hTLR9- and murine TLR9 (mTLR9)-expressing cells. Utilizing reporter cell lines, we demonstrate that purified gDNA from C. trachomatis can stimulate hTLR9 signaling, albeit at lower levels than gDNA prepared from other Gram-negative bacteria. Interestingly, we found that while C. trachomatis is capable of signaling through hTLR9 and mTLR9 during live infections in HEK293 reporter cell lines, signaling only occurs at later developmental time points. Chlamydia-specific induction of hTLR9 is blocked when protein synthesis is inhibited prior to the RB-to-EB conversion, exacerbated by the inhibition of lipooligosaccharide biosynthesis, and is significantly altered during the induction of aberrance/persistence. Our observations support the hypothesis that chlamydial gDNA is released during the conversion between the pathogen's replicative and infectious forms and during treatment with antibiotics targeting peptidoglycan assembly. Given that C. trachomatis inclusions do not co-localize with TLR9-containing vacuoles in the pro-monocytic cell line U937, our findings also hint that chlamydial gDNA is capable of egress from the inclusion, and traffics to TLR9-containing vacuoles via an as yet unknown pathway.

14.
Infect Immun ; 92(2): e0033923, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38214508

RESUMO

Diseases caused by Chlamydia spp. are often associated with persistent infections. Chlamydial persistence is commonly associated with a unique non-infectious intracellular developmental form, termed an aberrant form. Although infectious chlamydiae can be cultured consistently in cells stressed to aberrancy, their role in persistence is not clear. Recovery from antibiotic stress was explored as a model to determine how survival of non-aberrant chlamydiae, in the presence of fully inhibitory drug concentrations, may participate in persistence. Assays included incubation in quinolones, tetracyclines, or chloramphenicol for differing lengths of time, followed by an extended recovery period in antibiotic-free media. Culturable elementary bodies were not detected during treatment with each antibiotic, but viable and culturable Chlamydia trachomatis emerged after the drug was removed. Time-lapse imaging of live, antibiotic-treated infected cells identified metabolically dormant developmental forms within cells that emerged to form typical productive inclusions. The effects of the increasing concentration of most tested antibiotics led to predictable inhibitory activity, in which the survival rate decreased with increasing drug concentration. In contrast, in fluoroquinolone-treated cells, there was a paradoxical increase in productive development that was directly correlated with drug concentration and inversely associated with aberrant form production. This model system uncovers a unique chlamydial persistence pathway that does not involve the chlamydial aberrant form. The association between productive latency and metabolic dormancy is consistent with models for many bacterial species and may lead to a different interpretation of mechanisms of chlamydial persistence in patients.IMPORTANCEThe life history of most pathogens within the genus Chlamydia relies on lengthy persistence in the host. The most generally accepted model for Chlamydia spp. persistence involves an unusual developmental stage, termed the aberrant form, which arises during conditions that mimic a stressful host environment. In this work, we provide an alternate model for chlamydial persistence in the face of antibiotic stress. This model may be relevant to antibiotic treatment failures in patients infected with C. trachomatis.


Assuntos
Antibacterianos , Infecções por Chlamydia , Humanos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Chlamydia trachomatis , Infecções por Chlamydia/tratamento farmacológico , Infecções por Chlamydia/microbiologia
15.
Infect Immun ; 92(1): e0017923, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38014981

RESUMO

Chlamydia trachomatis and Neisseria gonorrhoeae are the most prevalent bacterial sexually transmitted infections (STIs) globally. Despite frequent co-infections in patients, few studies have investigated how mono-infections may differ from co-infections. We hypothesized that a symbiotic relationship between the pathogens could account for the high rates of clinical co-infection. During in vitro co-infection, we observed an unexpected phenotype where the C. trachomatis developmental cycle was impaired by N. gonorrhoeae. C. trachomatis is an obligate intracellular pathogen with a unique biphasic developmental cycle progressing from infectious elementary bodies (EB) to replicative reticulate bodies (RB), and back. After 12 hours of co-infection, we observed fewer EBs than in a mono-infection. Chlamydial genome copy number remained equivalent between mono- and co-infections. This is a hallmark of Chlamydial persistence. Chlamydial persistence alters inclusion morphology but varies depending on the stimulus/stress. We observed larger, but fewer, Chlamydia during co-infection. Tryptophan depletion can induce Chlamydial persistence, but tryptophan supplementation did not reverse the co-infection phenotype. Only viable and actively growing N. gonorrhoeae produced the inhibition phenotype in C. trachomatis. Piliated N. gonorrhoeae had the strongest effect on C. trachomatis, but hyperpiliated or non-piliated N. gonorrhoeae still produced the phenotype. EB development was modestly impaired when N. gonorrhoeae were grown in transwells above the infected monolayer. C. trachomatis serovar L2 was not impaired during co-infection. Chlamydial impairment could be due to cytoskeletal or osmotic stress caused by an as-yet-undefined mechanism. We conclude that N. gonorrhoeae induces a persistence-like state in C. trachomatis that is serovar dependent.


Assuntos
Infecções por Chlamydia , Coinfecção , Gonorreia , Humanos , Chlamydia trachomatis/genética , Neisseria gonorrhoeae , Infecções por Chlamydia/microbiologia , Triptofano
16.
Infect Immun ; 92(4): e0050323, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38451079

RESUMO

Non-neutralizing functions of antibodies, including phagocytosis, may play a role in Chlamydia trachomatis (CT) infection, but these functions have not been studied and assays are lacking. We utilized a flow-cytometry-based assay to determine whether serum samples from a well-characterized cohort of CT-infected and naïve control individuals enhanced phagocytosis via Fc-receptor-expressing THP-1 cells, and whether this activity correlated with antibody titers. Fc-receptor-mediated phagocytosis was detected only in CT+ donors. Phagocytosis generally did not correlate well with antibody titer. In addition, we found that complement from both CT+ and negative individuals enhanced phagocytosis of CT into primary neutrophils. These results suggest that anti-CT antibodies can have functions that are not reflected by titer. This method could be used to quantitively measure Fc-receptor-mediated function of anti-CT antibodies or complement activity and could reveal new immune correlates of protection.


Assuntos
Infecções por Chlamydia , Receptores Fc , Humanos , Fagocitose , Neutrófilos , Anticorpos Antibacterianos , Chlamydia trachomatis
17.
Clin Infect Dis ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38332660

RESUMO

Over the past two decades, cases of sexually transmitted infections (STIs) due to syphilis, gonorrhea, and chlamydia have been rising in the United States, disproportionately among gay, bisexual, and other men who have sex with men (MSM), as well as racial and ethnic minorities of all genders. In this review, we address updates about the evidence on doxycycline post-exposure prophylaxis (doxy-PEP) for prevention of bacterial STIs, including efficacy, safety, antimicrobial resistance (AMR), acceptability, modeling population impact, and evolving guidelines for use. Equitable implementation of doxy-PEP will require evaluation of who is offered and initiates it, understanding patterns of use and longer-term STI incidence and AMR, provider training, and tailored community education.

18.
Clin Infect Dis ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857177

RESUMO

BACKGROUND: Routine sexually transmitted infection and human immunodeficiency virus (STI/HIV) testing and HIV pre-exposure prophylaxis (PrEP) use are recommended for men who have sex with men (MSM) at increased risk of HIV. METHODS: Using Healthverity, a large administrative dataset in the United States, we assessed STI/HIV testing, chlamydia and gonorrhea positivity by specimen type, and HIV PrEP use among MSM and men who have sex with men and women (MSMW) at their first visits (index date) for those at increased risk of HIV and STIs from 2019 through 2022. RESULTS: Among 81,716 MSM and MSMW aged 15-64 years at their index date visit, STI testing rates were 57.9% for chlamydia, 58.1% for gonorrhea, and 52.2% for syphilis testing, respectively; 55.5%, 30.9%, and 18.1% had HIV testing, HIV PrEP use, and PrEP initiation, respectively, among the patients who did not have HIV. Of patients with chlamydia and gonorrhea testing, 48% were tested from the genital site only and 25% from three anatomic sites (rectal, pharyngeal, and urogenital). Chlamydia and gonorrhea positivity was 9.8% for chlamydia rectal infection, 7.3% for gonorrhea rectal infection, and 5.3% for gonorrhea pharyngeal infection. CONCLUSION: Our results present current medical services provided during initial clinic visits for MSM and MSMW in private outpatient settings. Our study suggests that the assessment of STI/HIV testing is periodically needed due to the high prevalence of infection, and efforts to promote HIV PrEP for MSM and MSMW in private settings are urgently needed.

19.
Emerg Infect Dis ; 30(4): 810-812, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38413241

RESUMO

Chlamydia pneumoniae infection cases have usually accounted for <1.5% of community-acquired respiratory tract infections. Currently, Lausanne, Switzerland is experiencing a notable upsurge in cases, with 28 reported within a span of a few months. This upsurge in cases highlights the need for heightened awareness among clinicians.


Assuntos
Infecções por Chlamydia , Chlamydophila pneumoniae , Infecções Comunitárias Adquiridas , Infecções Respiratórias , Humanos , Suíça/epidemiologia , Centros de Atenção Terciária , Infecções Respiratórias/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia
20.
Emerg Infect Dis ; 30(13): S62-S67, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38561843

RESUMO

We reviewed data obtained in October 2021-May 2023 from youth who reported a history of sexual activity upon admission to 1 of 12 juvenile justice facilities in Utah, USA, that offered screening for Chlamydia trachomatis and Neisseria gonorrhoeae. Urinalysis revealed C. trachomatis positivity of 10.77%, N. gonorrhoeae positivity of 1.08%, and coinfection C. trachomatis N. gonorrhoeae) of 0.90%. Prevalence of infection was similar for youths in rural and urban facilities. A total of 12.01% of those identifying as male and 14.01% of those identifying as female tested positive for C. trachomatis, N. gonorrhoeae, or coinfection. Of young adults who tested positive, 74.65% received their results while incarcerated, all of whom accepted treatment. Our research underscores the feasibility of providing prompt C. trachomatis/N. gonorrhoeae screening and treatment in juvenile correctional facilities. The pervasiveness of infection emphasizes the urgent need for early identification and treatment for C. trachomatis and N. gonorrhoeae in incarcerated youth nationwide.


Assuntos
Infecções por Chlamydia , Coinfecção , Gonorreia , Adulto Jovem , Adolescente , Masculino , Feminino , Humanos , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Utah/epidemiologia , Coinfecção/epidemiologia , Neisseria gonorrhoeae , Chlamydia trachomatis , Estabelecimentos Correcionais , Prevalência , Programas de Rastreamento/métodos
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