scholarly journals The Plasmid-Encoded pGP3 PromotesChlamydiaEvasion of Acidic Barriers in Both Stomach and Vagina

2019 ◽  
Vol 87 (5) ◽  
Author(s):  
Tianyuan Zhang ◽  
Zhi Huo ◽  
Jingyue Ma ◽  
Cheng He ◽  
Guangming Zhong
Keyword(s):  
Lactic Acid ◽  
Gastrointestinal Tract ◽  
Genital Tract ◽  
Sexual Transmission ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Lower Genital Tract ◽  
Colonization Ability ◽  
Gastric Barrier

ABSTRACTAlthoughChlamydia trachomatisis a human genital tract pathogen, chlamydial organisms have frequently been detected in both vaginal and rectal swab samples of animals and humans. The plasmid-encoded pGP3, a genital tract virulence factor, is essential forChlamydia muridarumto colonize the mouse gastrointestinal tract. However, intracolon inoculation to bypass the gastric barrier rescued the colonization ability of a pGP3-deficientC. muridarummutant, suggesting that pGP3 is required forC. muridarumto reach but not to colonize the large intestine. The pGP3-deficient mutant was rapidly cleared in the stomach and was 100-fold more susceptible to gastric killing. In mice genetically deficient in gastrin, a key regulator for gastric acid production, or pharmacologically treated with a proton pump inhibitor, the ability of pGP3-deficientC. muridarumto colonize the gastrointestinal tract was rescued. The pGP3-dependent resistance was further recapitulatedin vitrowith treatments with HCl, pepsin, or sarkosyl. In the genital tract, deficiency in pGP3 significantly reducedC. muridarumsurvival in the mouse vagina and increasedC. muridarumsusceptibility to vaginal killing by ∼8 times. The pGP3-deficientC. muridarumwas more susceptible to lactic acid killing, and the pGP3 deficiency also significantly increasedC. trachomatissusceptibility to lactic acid. The above-described observations together suggest thatChlamydiamay have acquired the plasmid-encoded pGP3 to overcome the gastric barrier during its adaptation to the gastrointestinal tract and the pGP3-dependent resistance may enable chlamydial evasion of the female lower genital tract barrier during sexual transmission.

scholarly journals The Chromosome-Encoded Hypothetical Protein TC0668 Is an Upper Genital Tract Pathogenicity Factor of Chlamydia muridarum

2015 ◽  
Vol 84 (2) ◽  
pp. 467-479 ◽  
Author(s):  
Turner Allen Conrad ◽  
Siqi Gong ◽  
Zhangsheng Yang ◽  
Patrick Matulich ◽  
Jonathon Keck ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Genital Tract ◽  
Hypothetical Protein ◽  
Genital Tract Infection ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Pathogenicity Factor ◽  
Lower Genital Tract ◽  
Lower Genital Tract Infection

We previously associated a missense mutation of thetc0668gene of serialin vitro-passagedChlamydia muridarum, a murine model of human urogenitalC. trachomatis, with severely attenuated disease development in the upper genital tract of female mice. Since these mutants also contained a TC0237 Q117E missense mutation that enhances theirin vitroinfectivity, an effort was made here to isolate and characterize atc0668single mutant to determine its individual contribution to urogenital pathogenicity. Detailed genetic analysis ofC. muridarumpassages revealed a truncated variant with a G216* nonsense mutation of the 408-amino-acid TC0668 protein that does not produce a detectable product. Intracellular growth and infectivity ofC. muridarum in vitroremain unaffected in the absence of TC0668. Intravaginal inoculation of the TC0668 null mutant into C3H/HeJ mice results in a typical course of lower genital tract infection but, unlike a pathogenic isogenic control, is unable to elicit significant chronic inflammation of the oviduct and fails to induce hydrosalpinx. Thus, TC0668 is demonstrated as an important chromosome-encoded urogenital pathogenicity factor ofC. muridarumand the first with these characteristics to be discovered for aChlamydiapathogen.

scholarly journals The Chlamydia-Secreted Protease CPAF Promotes Chlamydial Survival in the Mouse Lower Genital Tract

2016 ◽  
Vol 84 (9) ◽  
pp. 2697-2702 ◽  
Author(s):  
Zhangsheng Yang ◽  
Lingli Tang ◽  
Lili Shao ◽  
Yuyang Zhang ◽  
Tianyuan Zhang ◽  
...  
Keyword(s):  
Genital Tract ◽  
Chlamydial Infection ◽  
Critical Role ◽  
Content Type ◽  
Lower Genital Tract ◽  
Successful Infection ◽  
Multiple Strains

Despite the extensivein vitrocharacterization of CPAF (chlamydialprotease/proteasome-likeactivityfactor), its role in chlamydial infection and pathogenesis remains unclear. We now report that aChlamydia trachomatisstrain deficient in expression of CPAF (L2-17) is no longer able to establish a successful infection in the mouse lower genital tract following an intravaginal inoculation. The L2-17 organisms were cleared from the mouse lower genital tract within a few days, while a CPAF-sufficientC. trachomatisstrain (L2-5) survived in the lower genital tract for more than 3 weeks. However, both the L2-17 and L2-5 organisms maintained robust infection courses that lasted up to 4 weeks when they were directly delivered into the mouse upper genital tract. The CPAF-dependent chlamydial survival in the lower genital tract was confirmed in multiple strains of mice. Thus, we have demonstrated a critical role of CPAF in promotingC. trachomatissurvival in the mouse lower genital tracts. It will be interesting to further investigate the mechanisms of the CPAF-dependent chlamydial pathogenicity.

scholarly journals Intravenous Inoculation with Chlamydia muridarum Leads to a Long-Lasting Infection Restricted to the Gastrointestinal Tract

2016 ◽  
Vol 84 (8) ◽  
pp. 2382-2388 ◽  
Author(s):  
Jin Dai ◽  
Tianyuan Zhang ◽  
Luying Wang ◽  
Lili Shao ◽  
Cuiming Zhu ◽  
...  
Keyword(s):  
Sexual Behavior ◽  
Gastrointestinal Tract ◽  
Mouse Strain ◽  
Genital Tract ◽  
Ex Vivo ◽  
Circulatory System ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Initial Stage ◽  
Intravenous Inoculation

Chlamydiahas been detected in the gastrointestinal tracts of both animals and humans. However, it remains unclear whether the chlamydial organisms can be introduced into the gastrointestinal tract via pathways independent of the oral and anal routes. We have recently shown thatChlamydia muridarumspreads from the genital tract to the gastrointestinal tract potentially via the circulatory system. To test whether hematogenousC. muridarumcan spread to and establish a long-lasting colonization in the mouse gastrointestinal tract, we inoculated mice intravenously with a luciferase-expressingC. muridarumstrain and monitored its distribution. After tail vein inoculation, most luciferase-generated bioluminescence signals were detected in the mouse abdominal area throughout the experiment. Theex vivoimaging revealed that the abdominal signals came from the gastrointestinal tract tissues. Simultaneous monitoring of chlamydial organisms in individual organs or tissues revealed an initial stage of systemic spreading followed by a long-lasting infection in the gastrointestinal tract. A retro-orbital vein inoculation of theC. muridarumorganisms at a lower dose in a different mouse strain also led to colonization of the gastrointestinal tract. We have demonstrated that intravenousC. muridaruminoculation can result in colonization of the gastrointestinal tract, suggesting that the chlamydial organisms may use the sexual behavior-independent circulation pathway to infect the gastrointestinal tract.

scholarly journals Distinct Roles of Chromosome- versus Plasmid-Encoded Genital Tract Virulence Factors in PromotingChlamydia muridarumColonization in the Gastrointestinal Tract

2019 ◽  
Vol 87 (8) ◽  
Author(s):  
John J. Koprivsek ◽  
Tianyuan Zhang ◽  
Qi Tian ◽  
Ying He ◽  
Hong Xu ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Virulence Factors ◽  
Genital Tract ◽  
Oral Delivery ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Ifn Γ ◽  
Plasmid Mutant ◽  
Increased Susceptibility ◽  
Do So

ABSTRACTThe genital pathogenChlamydiais known to colonize the gastrointestinal tract. Orally deliveredChlamydia muridarumcan reach the colon and maintain a long-lasting colonization there. However,C. muridarumwith mutations in chromosomal genestc0237andtc0668(designated a chromosomal mutant) or deficient in plasmid-encoded pGP3 (designated a plasmid mutant) is unable to do so. We now report that the chromosomal mutant is still able to reach the colon while the plasmid mutant fails to do so following an oral delivery, suggesting that lack of colon colonization by different mutants may involve distinct mechanisms. Consistently, a direct intracolonic delivery selectively restored the ability of the plasmid mutant, but not the chromosomal mutant, to colonize the colon. The chromosomal mutant was rescued only in the colon of mice deficient in gamma interferon (IFN-γ). Thus, the chromosomal mutant’s deficiency in colonizing colonic mucosal tissue is likely due to its increased susceptibility to IFN-γ-mediated immunity. Furthermore, IFN-γ deficiency was sufficient for rescuing colon colonization of an orally delivered chromosomal mutant but not plasmid mutant while mice deficient in gastric acid production rescued the plasmid mutant but not the chromosomal mutant. Both mutants are attenuated in inducing genital tract pathology. Thus, we propose that chlamydial chromosomal-gene-encoded genital tract virulence factors may be essential forChlamydiato maintain long-lasting colonization in the colon while the plasmid may enableChlamydiato reach the colon by promoting evasion of gastric barriers.

scholarly journals Nonpathogenic Colonization with Chlamydia in the Gastrointestinal Tract as Oral Vaccination for Inducing Transmucosal Protection

2017 ◽  
Vol 86 (2) ◽  
Author(s):  
Luying Wang ◽  
Cuiming Zhu ◽  
Tianyuan Zhang ◽  
Qi Tian ◽  
Nu Zhang ◽  
...  
Keyword(s):  
T Cells ◽  
Gastrointestinal Tract ◽  
Antigen Presentation ◽  
Mhc Class Ii ◽  
Genital Tract ◽  
Genital Tract Infection ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Class Ii Antigen

ABSTRACTChlamydiahas been detected in the gastrointestinal tracts of humans and animals. We now report that gastrointestinalChlamydia muridarumis able to induce robust transmucosal protection in mice.C. muridarumcolonization in the gastrointestinal tract correlated with both a shortened course ofC. muridarumgenital tract infection and stronger protection against subsequent genital tract challenge infection. Mice preinoculated intragastrically withC. muridarumbecame highly resistant to subsequentC. muridaruminfection in the genital tract, resulting in prevention of pathology in the upper genital tract. The transmucosal protection in the genital tract was rapidly induced, durable, and dependent on major histocompatibility complex (MHC) class II antigen presentation but not MHC class I antigen presentation. Although a deficiency in CD4+T cells only partially reduced the transmucosal protection, depletion of CD4+T cells from B cell-deficient mice completely abolished the protection, suggesting a synergistic role of both CD4+T and B cells in the gastrointestinalC. muridarum-induced transmucosal immunity. However, the same protective immunity did not significantly affectC. muridarumcolonization in the gastrointestinal tract. The long-lasting colonization withC. muridarumwas restricted to the gastrointestinal tract and was nonpathogenic to either gastrointestinal or extragastrointestinal tissues. Furthermore, gastrointestinalC. muridarumdid not alter the gut microbiota or the development of gut mucosal resident memory T cell responses to a nonchlamydial infection. Thus,Chlamydiamay be developed into a safe and orally deliverable replicating vaccine for inducing transmucosal protection.

scholarly journals The Genital Tract Virulence Factor pGP3 Is Essential for Chlamydia muridarum Colonization in the Gastrointestinal Tract

2017 ◽  
Vol 86 (1) ◽  
Author(s):  
Lili Shao ◽  
Tianyuan Zhang ◽  
Jose Melero ◽  
Yumeng Huang ◽  
Yuanjun Liu ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Virulence Factor ◽  
Genital Tract ◽  
Gi Tract ◽  
Content Dissemination ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Colonization Factor ◽  
Genital Tract Infections ◽  
Tract Infections

ABSTRACTThe cryptic plasmid is essential forChlamydia muridarumdissemination from the genital tract to the gastrointestinal (GI) tract. Following intravaginal inoculation, aC. muridarumstrain deficient in plasmid-encoded pGP3 or pGP4 but not pGP5, pGP7, or pGP8 failed to spread to the mouse gastrointestinal tract, although mice infected with these strains developed productive genital tract infections. pGP3- or pGP4-deficient strains also failed to colonize the gastrointestinal tract when delivered intragastrically. pGP4 regulates pGP3, while pGP3 does not affect pGP4 expression, indicating that pGP3 is critical forC. muridarumcolonization of the gastrointestinal tract. Mutants deficient in GlgA, a chromosome-encoded protein regulated by pGP4, also consistently colonized the mouse gastrointestinal tract. Interestingly,C. muridarumcolonization of the gastrointestinal tract positively correlated with pathogenicity in the upper genital tract. pGP3-deficientC. muridarumstrains did not induce hydrosalpinx or spread to the GI tract even when delivered to the oviduct by intrabursal inoculation. Thus, the current study not only has revealed that pGP3 is a novel chlamydial colonization factor in the gastrointestinal tract but also has laid a foundation for investigating the significance of gastrointestinalChlamydia.

scholarly journals Reduced Live Organism Recovery and Lack of Hydrosalpinx in Mice Infected with Plasmid-Free Chlamydia muridarum

2013 ◽  
Vol 82 (3) ◽  
pp. 983-992 ◽  
Author(s):  
Lei Lei ◽  
Jianlin Chen ◽  
Shuping Hou ◽  
Yiling Ding ◽  
Zhangsheng Yang ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Genital Tract ◽  
Chlamydial Infection ◽  
High Dose ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Lower Genital Tract ◽  
Severe Pathology ◽  
Different Strains ◽  
Live Organism

ABSTRACTPlasmid-freeChlamydia trachomatisandChlamydia muridarumfail to induce severe pathology. To evaluate whether the attenuated pathogenicity is due to insufficient infection or inability of the plasmidless chlamydial organisms to trigger pathological responses, we compared plasmid-competent and plasmid-freeC. muridaruminfections in 5 different strains of mice. All 5 strains developed hydrosalpinx following intravaginal inoculation with plasmid-competent, but not inoculation with plasmid-free,C. muridarum. The lack of hydrosalpinx induction by plasmid-freeC. muridarumcorrelated with significantly reduced live organism recovery from the lower genital tract and shortened infection in the upper genital tract. The plasmid-freeC. muridarumorganisms failed to induce hydrosalpinx even when the organisms were directly inoculated into the oviduct via an intrabursal injection, which was accompanied by significantly reduced survival of the plasmidless organisms in the genital tracts. Furthermore, plasmid-competentC. muridarumorganisms after UV inactivation were no longer able to induce hydrosalpinx even when directly delivered into the oviduct at a high dose. Together, these observations suggest that decreased survival of and shortened infection with plasmid-freeC. muridarummay contribute significantly to its attenuated pathogenicity. We conclude that adequate live chlamydial infection in the oviduct may be necessary to induce hydrosalpinx.

scholarly journals A Genital Infection-Attenuated Chlamydia muridarum Mutant Infects the Gastrointestinal Tract and Protects against Genital Tract Challenge

mBio ◽  
2020 ◽  
Vol 11 (6) ◽  
Author(s):  
Sandra G. Morrison ◽  
Amanda M. Giebel ◽  
Evelyn Toh ◽  
Arkaprabha Banerjee ◽  
David E. Nelson ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Genital Tract ◽  
The United States ◽  
Effective Vaccine ◽  
Genital Infection ◽  
Wild Type ◽  
Gi Tract ◽  
Genital Infections ◽  
Content Type ◽  
Chlamydia Muridarum

ABSTRACT Chlamydia spp. productively infect mucosal epithelial cells of multiple anatomical sites, including the conjunctiva, lungs, gastrointestinal (GI) tract, and urogenital tract. We, and others, previously established that chlamydial GI tropism is mediated by distinct chromosomal and plasmid factors. In this study, we describe a genital infection-attenuated Chlamydia muridarum mutant (GIAM-1) that is profoundly and specifically attenuated in the murine genital tract. GIAM-1 infected the murine GI tract similarly to wild-type (WT) Chlamydia muridarum but did not productively infect the lower genital tract of female mice, ascend to infect the upper genital tract, or cause hydrosalpinx. However, GI infection of mice with GIAM-1 elicited a transmucosal immune response that protected against subsequent genital challenge with WT Chlamydia muridarum. Collectively, our results demonstrate that chlamydia mutants that are profoundly attenuated for specific organ tissues can be derived and demonstrate that live-attenuated vaccine strains that infect the GI tract, but do not elicit genital tract disease, could be used to protect against chlamydia genital tract infection and disease. IMPORTANCE Chlamydia is the most common sexually transmitted bacterial infection in the United States. Most chlamydia genital infections resolve without serious consequences; however, untreated infection in women can cause pelvic inflammatory disease and infertility. Antibiotics are very effective in treating chlamydia, but most genital infections in both men and women are asymptomatic and go undiagnosed. Therefore, there is a critical need for an effective vaccine. In this work, we show that a mutant chlamydia strain, having substantially reduced virulence for genital infection, colonizes the gastrointestinal tract and produces robust immunity to genital challenge with fully virulent wild-type chlamydia. These results are an important advance in understanding chlamydial virulence and provide compelling evidence that safe and effective live-attenuated chlamydia vaccines may be feasible.

scholarly journals Chlamydia muridarum with Mutations in Chromosomal Genes tc0237 and/or tc0668 Is Deficient in Colonizing the Mouse Gastrointestinal Tract

2017 ◽  
Vol 85 (8) ◽  
Author(s):  
Lili Shao ◽  
Tianyuan Zhang ◽  
Quanzhong Liu ◽  
Jie Wang ◽  
Guangming Zhong
Keyword(s):  
Gastrointestinal Tract ◽  
Genital Tract ◽  
Potential Role ◽  
Wild Type ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Primary Function ◽  
Ascending Infection ◽  
Chromosomal Genes

ABSTRACT Chlamydiae colonize the gastrointestinal tracts of both animals and humans. However, their medical significance remains unknown. We have previously shown that wild-type Chlamydia muridarum spreads to and establishes stable colonization of the gastrointestinal tract following intravaginal inoculation. In the present study, we found that C. muridarum with mutations in chromosomal genes tc0237 and/or tc0668 was defective in spreading to the mouse gastrointestinal tract, which correlated with its attenuated pathogenicity in the upper genital tract. This correlation was more consistent than that of chlamydial pathogenicity with ascending infection in the genital tract, since attenuated C. muridarum spread significantly less to the gastrointestinal tract but maintained robust ascending infection of the upper genital tract. Transcervical inoculation further confirmed the correlation between C. muridarum spreading to the gastrointestinal tract and its pathogenicity in the upper genital tract. Finally, defective spreading of C. muridarum mutants was due to their inability to colonize the gastrointestinal tract since intragastric inoculation did not rescue the mutants' colonization. Thus, promoting C. muridarum colonization of the gastrointestinal tract may represent a primary function of the TC0237 and TC0668 proteins. Correlation of chlamydial colonization of the gastrointestinal tract with chlamydial pathogenicity in the upper genital tract suggests a potential role for gastrointestinal chlamydiae in genital tract pathogenicity.

scholarly journals In VitroPassage Selects for Chlamydia muridarum with Enhanced Infectivity in Cultured Cells but Attenuated Pathogenicity in Mouse Upper Genital Tract

2015 ◽  
Vol 83 (5) ◽  
pp. 1881-1892 ◽  
Author(s):  
Chaoqun Chen ◽  
Zhou Zhou ◽  
Turner Conrad ◽  
Zhangsheng Yang ◽  
Jin Dai ◽  
...  
Keyword(s):  
Genital Tract ◽  
Selection Pressure ◽  
Cultured Cells ◽  
Serial Passage ◽  
Host Cells ◽  
Content Type ◽  
Chlamydia Muridarum ◽  
Low Incidence

Although modernChlamydia muridarumhas been passaged for decades, there are no reports on the consequences of serial passage with strong selection pressure on its fitness. In order to explore the potential for Pasteurian selection to induce genomic and phenotypic perturbations toC. muridarum, a starter population was passaged in cultured cells for 28 generations without standard infection assistance. The resultant population, designated CMG28, displays markedly reducedin vitrodependence on centrifugation for infection and low incidence and severity of upper genital tract pathology following intravaginal inoculation into mice compared to the parentalC. muridarumpopulation, CMG0. Deep sequencing of CMG0 and CMG28 revealed novel protein variants in the hypothetical genes TC0237 (Q117E) and TC0668 (G322R).In vitroattachment assays of isogenic plaque clone pairs with mutations in either TC0237 and TC0668 or only TC0237 reveal that TC0237(Q117E) is solely responsible for enhanced adherence to host cells. Paradoxically, double mutants, but not TC0237(Q117E) single mutants, display severely attenuatedin vivopathogenicity. These findings implicate TC0237 and TC0668 as novel genetic factors involved in chlamydial attachment and pathogenicity, respectively, and show that serial passage under selection pressure remains an effective tool for studyingChlamydiapathogenicity.

Sign in / Sign up

Export Citation Format

Share Document