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Li N, Xiao C, Li Y, Zhang Y, Lin Y, Liu Q, Tang L, Xu L, Ren Z. Association of Chlamydia trachomatis Infection With Breast Cancer Risk and the Modification Effect of IL-12. Clin Breast Cancer 2024:S1526-8209(24)00116-2. [PMID: 38821744 DOI: 10.1016/j.clbc.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 05/07/2024] [Indexed: 06/02/2024]
Abstract
BACKGROUND Chlamydia trachomatis (C. trachomatis) infection has been implicated in various cancers, yet its association with breast cancer remains unexplored. This infection triggers a cascade of immune responses primarily regulated by Interleukins-12 (IL-12). Thus, the objective of this case-control study was to investigate the link between C. trachomatis infection and breast cancer risk, as well as the modification effect of IL-12. METHODS We assessed IgG levels against C. trachomatis in serum of 1,121 women with breast cancer (861 with estrogen receptor-positive (ER+) and 260 with estrogen receptor-negative (ER-) tumors) and 400 controls in Guangzhou, China. Logistic regression models were applied to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for breast cancer risk in association with C. trachomatis infection. The interaction between C. trachomatis infection and IL-12 on breast cancer risk was estimated by the product terms in the logistic regression models. RESULTS Seropositivity of C. trachomatis IgG showed a slight association with an increased risk of breast cancer (OR = 1.20; 95% CI: 0.86∼1.78). This association was more pronounced among women with a higher (OR = 5.82; 95% CI: 1.31∼25.94) than a lower (OR = 0.73; 95% CI: 0.41∼1.30) level of IL-12, with a statistically significant interaction observed (Pinteraction = 0.013). In addition, C. trachomatis IgG seropositivity was related to an increased risk of breast cancer among PR+ patients (OR = 1.53; 95% CI: 1.04∼2.23). CONCLUSIONS C. trachomatis infection may contribute to the development of hormone-responsive breast cancer in women with high levels of IL-12. Further studies are needed to uncover the underlying mechanisms.
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Affiliation(s)
- Na Li
- School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Chengkun Xiao
- School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Yunqian Li
- School of Public Health, Sun Yat-sen University, Guangzhou, China; Shenzhen Pingle Orthopedic Hospital, Shenzhen, China
| | - Yixin Zhang
- School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Ying Lin
- The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Qiang Liu
- Sun Yat-Sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Luying Tang
- The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Lin Xu
- School of Public Health, Sun Yat-sen University, Guangzhou, China; School of Public Health, The University of Hong Kong, Hong Kong; Institute of Applied Health Research, University of Birmingham, Birmingham, UK.
| | - Zefang Ren
- School of Public Health, Sun Yat-sen University, Guangzhou, China.
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Zhao L, Wang X, Li Z. A novel chimeric recombinant FliC-Pgp3 vaccine promotes immunoprotection against Chlamydia muridarum infection in mice. Int J Biol Macromol 2024; 258:128723. [PMID: 38101679 DOI: 10.1016/j.ijbiomac.2023.128723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 12/17/2023]
Abstract
The Pgp3 subunit vaccine elicits immune protection against Chlamydia trachomatis infection, but additional adjuvants are still required to enhance its immunoprotective efficacy. Flagellin can selectively stimulate immunity and act as an adjuvant. In this research, the FliC-Pgp3 recombinant was successfully expressed and purified. Tri-immunization with the FliC-Pgp3 vaccine in Balb/C mice induced rapid and persistent germinal center B-cell response and Tfh differentiation, promoting a significantly higher IgG antibody titer compared to the Pgp3 group. FliC-Pgp3 immunization primarily induced Th1-type cellular immunity, leading to higher levels of IFN-γ, TNF-α, and IL-2 secreted by CD4+ T cells than in Pgp3-vaccinated mice. Chlamydia muridarum challenge results showed that FliC-Pgp3-vaccinated mice exhibited more rapid clearance of Chlamydia muridarum colonization in the lower genital tract, ensuring a lower hydrosalpinx rate and cumulative score. Histological analysis showed reduced dilation and inflammatory infiltration in the oviduct and uterine horn of FliC-Pgp3-vaccinated mice compared to the PBS and Pgp3 control. Importantly, tri-immunization with FliC-Pgp3 effectively activated CD4+ T cells and dendritic cells, as confirmed by the adoptive transfer, resulting in better immune protection in recipient mice. In summary, the novel FliC-Pgp3 chimeric is hoped to be a novel vaccine with improved immunoprotection against Chlamydia muridarum.
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Affiliation(s)
- Lanhua Zhao
- Institute of Pathogenic Biology, School of Nursing, Hengyang Medical College, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hunan Province, University of South China, Hengyang 421001, Hunan, People's Republic of China
| | - Xinglv Wang
- Institute of Pathogenic Biology, School of Nursing, Hengyang Medical College, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hunan Province, University of South China, Hengyang 421001, Hunan, People's Republic of China
| | - Zhongyu Li
- Institute of Pathogenic Biology, School of Nursing, Hengyang Medical College, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hunan Province, University of South China, Hengyang 421001, Hunan, People's Republic of China.
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Mercado MAB, Li Q, Quick CM, Kim Y, Palmer R, Huang L, Li LX. BHLHE40 drives protective polyfunctional CD4 T cell differentiation in the female reproductive tract against Chlamydia. PLoS Pathog 2024; 20:e1011983. [PMID: 38271477 PMCID: PMC10846703 DOI: 10.1371/journal.ppat.1011983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/06/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
The protein basic helix-loop-helix family member e40 (BHLHE40) is a transcription factor recently emerged as a key regulator of host immunity to infections, autoimmune diseases and cancer. In this study, we investigated the role of Bhlhe40 in protective T cell responses to the intracellular bacterium Chlamydia in the female reproductive tract (FRT). Mice deficient in Bhlhe40 exhibited severe defects in their ability to control Chlamydia muridarum shedding from the FRT. The heightened bacterial burdens in Bhlhe40-/- mice correlated with a marked increase in IL-10-producing T regulatory type 1 (Tr1) cells and decreased polyfunctional CD4 T cells co-producing IFN-γ, IL-17A and GM-CSF. Genetic ablation of IL-10 or functional blockade of IL-10R increased CD4 T cell polyfunctionality and partially rescued the defects in bacterial control in Bhlhe40-/- mice. Using single-cell RNA sequencing coupled with TCR profiling, we detected a significant enrichment of stem-like T cell signatures in Bhlhe40-deficient CD4 T cells, whereas WT CD4 T cells were further down on the differentiation trajectory with distinct effector functions beyond IFN-γ production by Th1 cells. Altogether, we identified Bhlhe40 as a key molecular driver of CD4 T cell differentiation and polyfunctional responses in the FRT against Chlamydia.
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Affiliation(s)
- Miguel A. B. Mercado
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Qiang Li
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Charles M. Quick
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Yejin Kim
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Rachel Palmer
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Lu Huang
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Lin-Xi Li
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
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Mercado MAB, Li Q, Quick CM, Kim Y, Palmer R, Huang L, Li LX. BHLHE40 drives protective polyfunctional CD4 T cell differentiation in the female reproductive tract against Chlamydia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.02.565369. [PMID: 37961221 PMCID: PMC10635079 DOI: 10.1101/2023.11.02.565369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The protein basic helix-loop-helix family member e40 (BHLHE40) is a transcription factor recently emerged as a key regulator of host immunity to infections, autoimmune diseases and cancer. In this study, we investigated the role of Bhlhe40 in protective T cell responses to the intracellular bacterium Chlamydia in the female reproductive tract (FRT). Mice deficient in Bhlhe40 exhibited severe defects in their ability to control Chlamydia muridarum shedding from the FRT. The heightened bacterial burdens in Bhlhe40-/- mice correlated with a marked increase in IL-10-producing T regulatory type 1 (Tr1) cells and decreased polyfunctional CD4 T cells co-producing IFN-γ, IL-17A and GM-CSF. Genetic ablation of IL-10 or functional blockade of IL-10R increased CD4 T cell polyfunctionality and partially rescued the defects in bacterial control in Bhlhe40-/- mice. Using single-cell RNA sequencing coupled with TCR profiling, we detected a significant enrichment of stem-like T cell signatures in Bhlhe40-deficient CD4 T cells, whereas WT CD4 T cells were further down on the differentiation trajectory with distinct effector functions beyond IFN-γ production by Th1 cells. Altogether, we identified Bhlhe40 as a key molecular driver of CD4 T cell differentiation and polyfunctional responses in the FRT against Chlamydia.
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Affiliation(s)
- Miguel A. B. Mercado
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Qiang Li
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Charles M. Quick
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Yejin Kim
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Rachel Palmer
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Lu Huang
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
| | - Lin-Xi Li
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205
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5
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Liu C, Mokashi NV, Darville T, Sun X, O’Connell CM, Hufnagel K, Waterboer T, Zheng X. A Machine Learning-Based Analytic Pipeline Applied to Clinical and Serum IgG Immunoproteome Data To Predict Chlamydia trachomatis Genital Tract Ascension and Incident Infection in Women. Microbiol Spectr 2023; 11:e0468922. [PMID: 37318345 PMCID: PMC10434056 DOI: 10.1128/spectrum.04689-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 06/01/2023] [Indexed: 06/16/2023] Open
Abstract
We developed a reusable and open-source machine learning (ML) pipeline that can provide an analytical framework for rigorous biomarker discovery. We implemented the ML pipeline to determine the predictive potential of clinical and immunoproteome antibody data for outcomes associated with Chlamydia trachomatis (Ct) infection collected from 222 cis-gender females with high Ct exposure. We compared the predictive performance of 4 ML algorithms (naive Bayes, random forest, extreme gradient boosting with linear booster [xgbLinear], and k-nearest neighbors [KNN]), screened from 215 ML methods, in combination with two different feature selection strategies, Boruta and recursive feature elimination. Recursive feature elimination performed better than Boruta in this study. In prediction of Ct ascending infection, naive Bayes yielded a slightly higher median value of are under the receiver operating characteristic curve (AUROC) 0.57 (95% confidence interval [CI], 0.54 to 0.59) than other methods and provided biological interpretability. For prediction of incident infection among women uninfected at enrollment, KNN performed slightly better than other algorithms, with a median AUROC of 0.61 (95% CI, 0.49 to 0.70). In contrast, xgbLinear and random forest had higher predictive performances, with median AUROC of 0.63 (95% CI, 0.58 to 0.67) and 0.62 (95% CI, 0.58 to 0.64), respectively, for women infected at enrollment. Our findings suggest that clinical factors and serum anti-Ct protein IgGs are inadequate biomarkers for ascension or incident Ct infection. Nevertheless, our analysis highlights the utility of a pipeline that searches for biomarkers and evaluates prediction performance and interpretability. IMPORTANCE Biomarker discovery to aid early diagnosis and treatment using machine learning (ML) approaches is a rapidly developing area in host-microbe studies. However, lack of reproducibility and interpretability of ML-driven biomarker analysis hinders selection of robust biomarkers that can be applied in clinical practice. We thus developed a rigorous ML analytical framework and provide recommendations for enhancing reproducibility of biomarkers. We emphasize the importance of robustness in selection of ML methods, evaluation of performance, and interpretability of biomarkers. Our ML pipeline is reusable and open-source and can be used not only to identify host-pathogen interaction biomarkers but also in microbiome studies and ecological and environmental microbiology research.
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Affiliation(s)
- Chuwen Liu
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Neha Vivek Mokashi
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Toni Darville
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Xuejun Sun
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Catherine M. O’Connell
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Katrin Hufnagel
- Infections and Cancer Epidemiology, German Cancer Research Center (Deutsches Krebsforschungszentrum), Heidelberg, Germany
| | - Tim Waterboer
- Infections and Cancer Epidemiology, German Cancer Research Center (Deutsches Krebsforschungszentrum), Heidelberg, Germany
| | - Xiaojing Zheng
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Yount KS, Kollipara A, Liu C, Zheng X, O'Connell CM, Bagwell B, Wiesenfeld HC, Hillier SL, Darville T. Unique T cell signatures are associated with reduced Chlamydia trachomatis reinfection in a highly exposed cohort. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551709. [PMID: 37577476 PMCID: PMC10418240 DOI: 10.1101/2023.08.02.551709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted infection (STI) in the United States, despite effective antibiotics. Information regarding natural immunity to CT will inform vaccine design. The objectives of this study were to determine immune cell populations and functional features associated with reduced risk of CT reinfection or endometrial CT infection. PBMCs were collected from a cohort of CT-exposed women who were tested for CT and other STIs at the cervix and endometrium (to determine ascension) and were repeatedly tested over the course of a year (to determine reinfection). Mass cytometry identified major immune populations and T cell subsets. Women with CT had increased CD4+ effector memory T cells (TEM) compared to uninfected women. Specifically, Th2, Th17, and Th17 DN CD4+ TEM were increased. Th17 and Th17 DN CD4+ central memory T cells (TCM) were increased in women who did not experience follow-up CT infection, suggesting that these cells may be important for protection. These data indicate that peripheral T cells display distinct features that correlate with natural immunity to CT and suggest that the highly plastic Th17 lineage plays a role in protection against reinfection.
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Gravitte A, Kintner J, Brown S, Cobble A, Kennard B, Hall JV. The hormonal environment and estrogen receptor signaling alters Chlamydia muridarum infection in vivo. Front Cell Infect Microbiol 2022; 12:939944. [PMID: 36636722 PMCID: PMC9831676 DOI: 10.3389/fcimb.2022.939944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 11/29/2022] [Indexed: 12/28/2022] Open
Abstract
Genital Chlamydia is the most common bacterial sexually transmitted infection in the United States and worldwide. Previous studies indicate that the progression of chlamydial infection is influenced by various factors, including the female sex hormones estrogen and progesterone. Sex hormone levels naturally fluctuate in women throughout their menstrual cycle. Varying concentrations of estrogen and progesterone may impact the progression of chlamydial infection and the host's immune response to Chlamydia. Estrogen signals through estrogen receptors (ERs), ERα and ERβ. These receptors are similar in structure and function, but are differentially expressed in tissues throughout the body, including the genital tract and on cells of the immune system. In this study, we used ovariectomized (OVT) BALB/c mice to investigate the impact of long-term administration of physiologically relevant concentrations of estrogen (E2), progesterone (P4), or a combination of E2/P4 on the progression of and immune response to C. muridarum infection. Additionally, we used ERα and ERβ knockout C57/BL6 mice to determine the how ERs affect chlamydial infection and the resulting immune response. Estrogen exposure prevented C. muridarum infection in vaginally infected OVT mice exposed to E2 alone or in combination with P4, while OVT or Sham mice exposed to hormone free, P4 or depo-medroxyprogesterone acetate shed similar amounts of chlamydiae. The hormonal environment also altered T cell recruitment and IFNϵ production the genital tracts of infected OVT and Sham mice on day 10 post infection. The absence of ERα, but not ERβ, in ER knockout mouse strains significantly changed the timing of C. muridarum infection. ERαKO mice shed significantly more chlamydiae at day 3 post infection and resolved the infection faster than WT or ERβKO animals. At day 9 post infection, flow cytometry showed that ERαKO mice had more T cells present and targeted RNA sequencing revealed increased expression of CD4 and FOXP3, suggesting that ERαKO mice had increased numbers of regulatory T cells compared to ERβKO and WT mice. Mock and chlamydia-infected ERαKO mice also expressed more IFNϵ early during infection. Overall, the data from these studies indicate that sex hormones and their receptors, particularly ERα and ERβ, differentially affect C. muridarum infection in murine models of infection.
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Affiliation(s)
- Amy Gravitte
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States,Center of Excellence for Inflammation, Infection Disease, and Immunity, East Tennessee State University, Johnson City, TN, United States
| | - Jennifer Kintner
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States
| | - Stacy Brown
- Department of Pharmaceutical Sciences, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN, United States
| | - Allison Cobble
- Department of Pharmaceutical Sciences, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN, United States
| | - Benjamin Kennard
- Department of Pharmaceutical Sciences, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN, United States
| | - Jennifer V. Hall
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States,Center of Excellence for Inflammation, Infection Disease, and Immunity, East Tennessee State University, Johnson City, TN, United States,*Correspondence: Jennifer V. Hall,
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Nguyen NDNT, Guleed S, Olsen AW, Follmann F, Christensen JP, Dietrich J. Th1/Th17 T cell Tissue-Resident Immunity Increases Protection, But Is Not Required in a Vaccine Strategy Against Genital Infection With Chlamydia trachomatis. Front Immunol 2021; 12:790463. [PMID: 34925371 PMCID: PMC8674352 DOI: 10.3389/fimmu.2021.790463] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
The requirement for vaccine-induced tissue-resident immunity for protection against one or repeated infections with Chlamydia trachomatis (C.t.) is still not fully resolved. In this study, our aim was to investigate to which degree tissue-resident Th1/Th17 T cells in the genital tract (GT) could add to the protection mediated by circulating immunity. Out of several mucosal vaccine strategies, a strategy termed SIM (for simultaneous intrauterine and parenteral immunization with CAF01 adjuvanted CTH522), was superior in generating genital tract tissue-resident Th1/Th17 T cell immunity. This led to a faster and stronger local CD4 T cell response post infection, consisting of multifunctional IFNγ/TNFα-producing Th1 T cells and IFNγ/TNFα/IL-17-producing Th17 T cells, and a faster recruitment of innate immune cells. Post infection, SIM animals showed an additional significant reduction in bacterial levels compared to mice having received only a parenteral vaccine. Nevertheless, the parenteral strategy reduced bacterial levels by 75%, and interestingly, post infection, these mice generated their own vaccine-derived genital tract tissue-resident memory Th1/Th17 T cells, which upon a subsequent infection showed as fast an activation in the genital tract, as observed in SIM mice. Furthermore, in contrast to after the first infection, both groups of mice now showed a similar infection-induced boost in local vaginal IgA and IgG titers. Thus, vaccine-induced resident immunity, generated pre-infection, led to an advantage in the response against the first infection, but not the second infection, suggesting that a parenteral vaccine strategy is a suitable vaccine strategy against infections with Chlamydia trachomatis.
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Affiliation(s)
| | - Safia Guleed
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Anja Weinreich Olsen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Frank Follmann
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | | | - Jes Dietrich
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
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D Helble J, N Starnbach M. T cell responses to Chlamydia. Pathog Dis 2021; 79:6164867. [PMID: 33693620 DOI: 10.1093/femspd/ftab014] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 03/07/2021] [Indexed: 12/27/2022] Open
Abstract
Chlamydia trachomatis is the most commonly reported sexually transmitted infection in the United States. The high prevalence of infection and lack of a vaccine indicate a critical knowledge gap surrounding the host's response to infection and how to effectively generate protective immunity. The immune response to C. trachomatis is complex, with cells of the adaptive immune system playing a crucial role in bacterial clearance. Here, we discuss the CD4+ and CD8+ T cell response to Chlamydia, the importance of antigen specificity and the role of memory T cells during the recall response. Ultimately, a deeper understanding of protective immune responses is necessary to develop a vaccine that prevents the inflammatory diseases associated with Chlamydia infection.
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Affiliation(s)
- Jennifer D Helble
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
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10
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Innate IFN-γ Is Essential for Systemic Chlamydia muridarum Control in Mice, While CD4 T Cell-Dependent IFN-γ Production Is Highly Redundant in the Female Reproductive Tract. Infect Immun 2021; 89:IAI.00541-20. [PMID: 33257535 PMCID: PMC8097277 DOI: 10.1128/iai.00541-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 11/17/2020] [Indexed: 12/15/2022] Open
Abstract
Protective immunity against the obligate intracellular bacterium Chlamydia has long been thought to rely on CD4 T cell-dependent gamma interferon (IFN-γ) production. Nevertheless, whether IFN-γ is produced by other cellular sources during Chlamydia infection and how CD4 T cell-dependent and -independent IFN-γ contribute differently to host resistance have not been carefully evaluated. In this study, we dissected the requirements of IFN-γ produced by innate immune cells and CD4 T cells for resolution of Chlamydia muridarum female reproductive tract (FRT) infection. After C. muridarum intravaginal infection, IFN-γ-deficient and T cell-deficient mice exhibited opposite phenotypes for survival and bacterial shedding at the FRT mucosa, demonstrating the distinct requirements for IFN-γ and CD4 T cells in host defense against Chlamydia In Rag1-deficient mice, IFN-γ produced by innate lymphocytes (ILCs) accounted for early bacterial control and prolonged survival in the absence of adaptive immunity. Although type I ILCs are potent IFN-γ producers, we found that mature NK cells and ILC1s were not the sole sources of innate IFN-γ in response to Chlamydia By conducting T cell adoptive transfer, we showed definitively that IFN-γ-deficient CD4 T cells were sufficient for effective bacterial killing in the FRT during the first 21 days of infection and reduced bacterial burden more than 1,000-fold, although mice receiving IFN-γ-deficient CD4 T cells failed to completely eradicate the bacteria from the FRT like their counterparts receiving wild-type (WT) CD4 T cells. Together, our results revealed that innate IFN-γ is essential for preventing systemic Chlamydia dissemination, whereas IFN-γ produced by CD4 T cells is largely redundant at the FRT mucosa.
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Helble JD, Gonzalez RJ, von Andrian UH, Starnbach MN. Gamma Interferon Is Required for Chlamydia Clearance but Is Dispensable for T Cell Homing to the Genital Tract. mBio 2020; 11:e00191-20. [PMID: 32184237 PMCID: PMC7078466 DOI: 10.1128/mbio.00191-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 01/30/2020] [Indexed: 01/08/2023] Open
Abstract
While there is no effective vaccine against Chlamydia trachomatis infection, previous work has demonstrated the importance of C. trachomatis-specific CD4+ T cells (NR1 T cells) in pathogen clearance. Specifically, NR1 T cells have been shown to be protective in mice, and this protection depends on the host's ability to sense the cytokine gamma interferon (IFN-γ). However, it is unclear what role NR1 production or sensing of IFN-γ plays in T cell homing to the genital tract or T cell-mediated protection against C. trachomatis Using two-photon microscopy and flow cytometry, we found that naive wild-type (WT), IFN-γ-/-, and IFN-γR-/- NR1 T cells specifically home to sections in the genital tract that contain C. trachomatis We also determined that protection against infection requires production of IFN-γ from either NR1 T cells or endogenous cells, further highlighting the importance of IFN-γ in clearing C. trachomatis infection.IMPORTANCEChlamydia trachomatis is an important mucosal pathogen that is the leading cause of sexually transmitted bacterial infections in the United States. Despite this, there is no vaccine currently available. In order to develop such a vaccine, it is necessary to understand the components of the immune response that can lead to protection against this pathogen. It is well known that antigen-specific CD4+ T cells are critical for Chlamydia clearance, but the contexts in which they are protective or not protective are unknown. Here, we aimed to characterize the importance of gamma interferon production and sensing by T cells and the effects on the immune response to C. trachomatis Our work here helps to define the contexts in which antigen-specific T cells can be protective, which is critical to our ability to design an effective and protective vaccine against C. trachomatis.
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Affiliation(s)
- Jennifer D Helble
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Rodrigo J Gonzalez
- Department of Immunology, Harvard Medical School, Boston, Massachusetts, USA
| | - Ulrich H von Andrian
- Department of Immunology, Harvard Medical School, Boston, Massachusetts, USA
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Michael N Starnbach
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
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12
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Nguyen NDNT, Olsen AW, Lorenzen E, Andersen P, Hvid M, Follmann F, Dietrich J. Parenteral vaccination protects against transcervical infection with Chlamydia trachomatis and generate tissue-resident T cells post-challenge. NPJ Vaccines 2020; 5:7. [PMID: 31993218 PMCID: PMC6978417 DOI: 10.1038/s41541-020-0157-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 12/20/2019] [Indexed: 11/21/2022] Open
Abstract
The optimal protective immunity against Chlamydia trachomatis (C.t.) is still not fully resolved. One of the unresolved issues concerns the importance of resident immunity, since a recent study showed that optimal protection against a transcervical (TC) infection required genital tissue-resident memory T cells. An important question in the Chlamydia field is therefore if a parenteral vaccine strategy, inducing only circulating immunity primed at a nonmucosal site, should be pursued by Chlamydia vaccine developers. To address this question we studied the protective efficacy of a parenteral Chlamydia vaccine, formulated in the Th1/Th17 T cell-inducing adjuvant CAF01. We found that a parenteral vaccination induced significant protection against a TC infection and against development of chronic pathology. Protection correlated with rapid recruitment of Th1/Th17 T cells to the genital tract (GT), which efficiently prevented infection-driven generation of low quality Th1 or Th17 T cells, and instead maintained a pool of high quality multifunctional Th1/Th17 T cells in the GT throughout the infection. After clearance of the infection, a pool of these cells settled in the GT as tissue-resident Th1 and Th17 cells expressing CD69 but not CD103, CD49d, or CCR7, where they responded rapidly to a reinfection. These results show that a nonmucosal parenteral strategy inducing Th1 and Th17 T cells mediates protection against both infection with C.t. as well as development of chronic pathology, and lead to post-challenge protective tissue-resident memory immunity in the genital tract.
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Affiliation(s)
| | - Anja W Olsen
- 1Statens Serum Institut, Department for Infectious Disease Immunology, Copenhagen, Denmark
| | - Emma Lorenzen
- 1Statens Serum Institut, Department for Infectious Disease Immunology, Copenhagen, Denmark
| | - Peter Andersen
- 1Statens Serum Institut, Department for Infectious Disease Immunology, Copenhagen, Denmark
| | - Malene Hvid
- 2Department of Biomedicine and Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Frank Follmann
- 1Statens Serum Institut, Department for Infectious Disease Immunology, Copenhagen, Denmark
| | - Jes Dietrich
- 1Statens Serum Institut, Department for Infectious Disease Immunology, Copenhagen, Denmark
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13
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Early Colonization of the Upper Genital Tract by Chlamydia muridarum Is Associated with Enhanced Inflammation Later in Infection. Infect Immun 2019; 87:IAI.00405-19. [PMID: 31285254 DOI: 10.1128/iai.00405-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/02/2019] [Indexed: 12/23/2022] Open
Abstract
Chlamydia trachomatis is the most commonly reported bacterial sexually transmitted infection in the United States. Modeling infection in animals can be challenging, as mice naturally clear C. trachomatis when it is deposited in the lower genital tract. However, C. trachomatis can productively infect mice when the lower genital tract is bypassed and bacteria are deposited directly into the upper genital tract via transcervical inoculation. Interestingly, the mouse-adapted Chlamydia species C. muridarum can infect mice both by transcervical inoculation and by natural ascension if introduced into the vaginal vault. In this study, we investigated whether the route of infection plays a role in the downstream immune responses to C. muridarum infection. We found that transcervical infection with C. muridarum results in higher bacterial burdens in the upper genital tract at earlier time points, correlating with levels of innate immune cells. When bacterial burdens were equivalent in intravaginally and transcervically infected mice at later time points, we observed substantially higher levels of adaptive immune cells in transcervically infected mice. Our data suggest that different routes of infection with the same organism can elicit different immune responses in the same tissue.
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14
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A Chlamydia trachomatis Strain Expressing Ovalbumin Stimulates an Antigen-Specific CD4 + T Cell Response in Mice. Infect Immun 2019; 87:IAI.00837-18. [PMID: 30988057 DOI: 10.1128/iai.00837-18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 04/09/2019] [Indexed: 11/20/2022] Open
Abstract
Antigen-specific CD4+ T cells against Chlamydia are crucial for driving bacterial clearance and mediating protection against reinfection. Although the Chlamydia trachomatis protein Cta1 has been identified to be a dominant murine CD4+ T cell antigen, its level of expression during the bacterial developmental cycle and precise localization within the host cell are unknown. Newly developed tools for Chlamydia genetic manipulation have allowed us to generate a C. trachomatis strain expressing a heterologous CD4+ T cell epitope from ovalbumin (OVA) consisting of OVA residues 323 to 339 (OVA323-339). By tagging proteins expressed in C. trachomatis with OVA323-339, we can begin to understand how protein expression, developmental regulation, and subcellular compartmentalization affect the potential of those proteins to serve as antigens. When OVA323-339 was expressed as a fusion with green fluorescent protein, we found that we were able to elicit an OT-II T cell response in an antigen-dependent manner, but surprisingly, these T cells were unable to reduce bacterial burden in mice. These data suggest that the subcellular localization of antigen, the level of antigen expression, or the timing of expression within the developmental cycle of Chlamydia may play a crucial role in eliciting a protective CD4+ T cell response.
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15
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Sanchez LR, Godoy GJ, Gorosito Serrán M, Breser ML, Fiocca Vernengo F, Engel P, Motrich RD, Gruppi A, Rivero VE. IL-10 Producing B Cells Dampen Protective T Cell Response and Allow Chlamydia muridarum Infection of the Male Genital Tract. Front Immunol 2019; 10:356. [PMID: 30881362 PMCID: PMC6405527 DOI: 10.3389/fimmu.2019.00356] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 02/12/2019] [Indexed: 12/26/2022] Open
Abstract
A significant proportion of individuals develop chronic, persistent and recurrent genital tract infections with Chlamydia trachomatis, which has been attributed to the numerous strategies that the bacterium uses to subvert host immune responses. Animal chlamydia models have demonstrated that protective immune response is mediated by CD4+ Th1 cytokine responses. Herein, we demonstrate that early after infecting the male genital tract, C. muridarum triggers the production of IL-10 by splenic and lymph node cells. In addition, C. muridarum triggers IL-6 and TNFα secretion. Data obtained from in vitro and in vivo experiments revealed B cells as the major IL-10 contributors. Indeed, purified B cells produced high amounts of IL-10 and also exhibited enhanced expression of inhibitory molecules such as CD39, PD-L1 and PD1 after C. muridarum stimulation. In vitro experiments performed with sorted cell subsets revealed that Marginal Zone B cells were the main IL-10 producers. In vitro and in vivo studies using TLR-deficient mice indicated that TLR4 signaling pathway was essential for IL-10 production. In addition, in vivo treatments to neutralize IL-10 or deplete B cells indicated that IL-10 and B cells played a significant role in delaying bacterial clearance ability. Moreover, the latter was confirmed by adoptive cell transfer experiments in which the absence of IL-10-producing B cells conferred the host a greater capability to induce Th1 responses and clear the infection. Interestingly, NOD mice, which were the least efficient in clearing the infection, presented much more Marginal Zone B counts and also enhanced TLR4 expression on Marginal Zone B cells when compared to B6 and BALB/c mice. Besides, treatment with antibodies that selectively deplete Marginal Zone B cells rendered mice more capable of inducing enhanced IFNγ responses and clearing the infection. Our findings suggest that B cells play a detrimental role in C. muridarum infection and that activation by innate receptors like TLR4 and IL-10 production by these cells could be used by Chlamydia spp. as a strategy to modulate the immune response establishing chronic infections in susceptible hosts.
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Affiliation(s)
- Leonardo R Sanchez
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Gloria J Godoy
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Melisa Gorosito Serrán
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Maria L Breser
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Facundo Fiocca Vernengo
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Pablo Engel
- Immunology Unit, Department of Biomedical Sciences, Immunology and Neurosciences, Medical School, University of Barcelona, Barcelona, Spain
| | - Ruben D Motrich
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Adriana Gruppi
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Virginia E Rivero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología, CIBICI-CONICET, Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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16
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Labuda JC, McSorley SJ. Diversity in the T cell response to Chlamydia-sum are better than one. Immunol Lett 2018; 202:59-64. [PMID: 30179654 DOI: 10.1016/j.imlet.2018.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/10/2018] [Accepted: 08/15/2018] [Indexed: 02/06/2023]
Abstract
Chlamydia trachomatis is responsible for an increasing number of sexually transmitted infections in the United States and is a common cause of serious pathology in the female reproductive tract (FRT). Given the impact and incidence of these infections, the production of an effective Chlamydia vaccine is a public health priority. Mouse models of Chlamydia infection have been utilized to develop a detailed and mechanistic understanding of protective immunity in the FRT. These studies reveal that MHC class-II restricted Chlamydia-specific CD4 T cells are critical for primary bacterial clearance and provide effective protection against secondary infection in the FRT. Despite the clear importance of IFN- γ produced by CD4 Th1 cells, there are also suggestions of wider functional heterogeneity in the CD4 T cell response to Chlamydia infection. Understanding the role of this diversity in the CD4 T helper cell response in the FRT should allow a more nuanced view of CD4 T cell biology in the context of Chlamydia infection and may be critical for vaccine development. Here, we summarize our current understanding of CD4 T helper subsets in the clearance of Chlamydia and discuss some areas where knowledge needs to be further extended by additional experimentation.
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Affiliation(s)
- Jasmine C Labuda
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States.
| | - Stephen J McSorley
- Center for Comparative Medicine, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, United States
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17
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Poston TB, O'Connell CM, Girardi J, Sullivan JE, Nagarajan UM, Marinov A, Scurlock AM, Darville T. T Cell-Independent Gamma Interferon and B Cells Cooperate To Prevent Mortality Associated with Disseminated Chlamydia muridarum Genital Tract Infection. Infect Immun 2018; 86:e00143-18. [PMID: 29661927 PMCID: PMC6013674 DOI: 10.1128/iai.00143-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 04/04/2018] [Indexed: 12/18/2022] Open
Abstract
CD4 T cells and antibody are required for optimal acquired immunity to Chlamydia muridarum genital tract infection, and T cell-mediated gamma interferon (IFN-γ) production is necessary to clear infection in the absence of humoral immunity. However, the role of T cell-independent immune responses during primary infection remains unclear. We investigated this question by inoculating wild-type and immune-deficient mice with C. muridarum CM001, a clonal isolate capable of enhanced extragenital replication. Genital inoculation of wild-type mice resulted in transient dissemination to the lungs and spleen that then was rapidly cleared from these organs. However, CM001 genital infection proved lethal for STAT1-/- and IFNG-/- mice, in which IFN-γ signaling was absent, and for Rag1-/- mice, which lacked T and B cells and in which innate IFN-γ signaling was retained. In contrast, B cell-deficient muMT mice, which can generate a Th1 response, and T cell-deficient mice with intact B cell and innate IFN-γ signaling survived. These data collectively indicate that IFN-γ prevents lethal CM001 dissemination in the absence of T cells and suggests a B cell corequirement. Adoptive transfer of convalescent-phase immune serum but not naive IgM to Rag1-/- mice infected with CM001 significantly increased the survival time, while transfer of naive B cells completely rescued Rag1-/- mice from CM001 lethality. Protection was associated with a significant reduction in the lung chlamydial burden of genitally infected mice. These data reveal an important cooperation between T cell-independent B cell responses and innate IFN-γ in chlamydial host defense and suggest that interactions between T cell-independent antibody and IFN-γ are essential for limiting extragenital dissemination.
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Affiliation(s)
- Taylor B Poston
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Catherine M O'Connell
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jenna Girardi
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jeanne E Sullivan
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Uma M Nagarajan
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Anthony Marinov
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Amy M Scurlock
- Department of Pediatrics, Arkansas Children's Hospital, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Toni Darville
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA
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18
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Zhong G. Chlamydia Spreading from the Genital Tract to the Gastrointestinal Tract - A Two-Hit Hypothesis. Trends Microbiol 2017; 26:611-623. [PMID: 29289422 DOI: 10.1016/j.tim.2017.12.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/21/2017] [Accepted: 12/06/2017] [Indexed: 12/18/2022]
Abstract
Chlamydia trachomatis, a leading bacterial cause of sexually transmitted infection-induced infertility, is frequently detected in the gastrointestinal tract. Chlamydia muridarum, a model pathogen for investigating C. trachomatis pathogenesis, readily spreads from the mouse genital tract to the gastrointestinal tract, establishing long-lasting colonization. C. muridarum mutants, despite their ability to activate acute oviduct inflammation, are attenuated in inducing tubal fibrosis and are no longer able to colonize the gastrointestinal tract, suggesting that the spread of C. muridarum to the gastrointestinal tract may contribute to its pathogenicity in the upper genital tract. However, gastrointestinal C. muridarum cannot directly autoinoculate the genital tract. Both antigen-specific CD8+ T cells and profibrotic cytokines, such as TNFα and IL-13, are essential for C. muridarum to induce tubal fibrosis; this may be induced by the gastrointestinal C. muridarum, as a second hit, to transmucosally convert tubal repairing - initiated by C. muridarum infection of tubal epithelial cells (serving as the first hit) - into pathogenic fibrosis. Testing the two-hit mouse model should both add new knowledge to the growing list of mechanisms by which gastrointestinal microbes contribute to pathologies in extragastrointestinal tissues and provide information for investigating the potential role of gastrointestinal C. trachomatis in human chlamydial pathogenesis.
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Affiliation(s)
- Guangming Zhong
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health, Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
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