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Norris SJ. Establishment of the Nichols strain as the type strain of Treponema pallidum. Int J Syst Evol Microbiol 2025; 75:006697. [PMID: 40014041 PMCID: PMC11868658 DOI: 10.1099/ijsem.0.006697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2024] [Accepted: 02/16/2025] [Indexed: 02/28/2025] Open
Abstract
In this article, it is proposed that the Nichols strain of Treponema pallidum be established as the type strain. T. pallidum was first identified as the causative agent of syphilis in 1905, and the Nichols strain was isolated in 1912 by inoculation of a rabbit with cerebrospinal fluid from a patient with neurosyphilis. The Nichols strain has been maintained by serial passage in rabbits for over a century, and historically most studies of T. pallidum have been conducted using this strain. In recent years, a procedure for continuous in vitro culture of T. pallidum in a tissue culture system has been developed, making propagation of this spirochaete easier and hence facilitating research. The Nichols strain has >99% DNA homology with a group of organisms that cause syphilis, bejel/endemic syphilis and yaws in humans, a yaws-like disease in primates and spirochaetosis in rabbits and hares. This group is highly similar in terms of their gene and G+C content, genome synteny, cell morphology, natural dependence on mammalian hosts and ability to cause long-term infections; variation occurs in host range, modes of transmission, aptitude for dissemination, manifestations, congenital infection and geographical distribution. Availability of a type strain will aid in the formal acceptance of T. pallidum subspecies first described in 1984 and supported by recent whole-genome analyses of numerous strains from the T. pallidum-related group.
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Affiliation(s)
- Steven J. Norris
- Department of Pathology and Laboratory Medicine, McGovern Medical School, University of Texas Health Sciences Center at Houston, Houston, Texas, USA
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Sciences Center at Houston, Houston, Texas, USA
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Allan-Blitz LT, Mayer KH. Doxycycline Post-Exposure Prophylaxis for Bacterial Sexually Transmitted Infections: The Current Landscape and Future Directions. Curr HIV/AIDS Rep 2024; 22:1. [PMID: 39476167 PMCID: PMC11994091 DOI: 10.1007/s11904-024-00709-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2024] [Indexed: 03/29/2025]
Abstract
PURPOSE OF REVIEW The incidence of bacterial sexually transmitted infections (STI) continues to rise particularly among men who have sex with men (MSM). Doxycycline post-exposure prophylaxis (doxy-PEP) has emerged as a promising biomedical prevention strategy. This review aims to summarize the results of recent studies, highlight the current normative guidance on the use of doxy-PEP, and discuss remaining questions. RECENT FINDINGS In the past decade, there have been four randomized controlled trials and three real-world analyses of doxy-PEP, which consistently demonstrated a reduction in Chlamydia trachomatis and Treponema pallidum infections among MSM. Questions remain regarding the efficacy of doxy-PEP for Neisseria gonorrhoeae infection and among cisgender women. Possible detrimental impacts include an increase in antimicrobial resistance as well as alterations to the gut microbiome Doxy-PEP is an effective strategy for preventing Chlamydia trachomatis and Treponema pallidum among MSM. Further work is needed to investigate the benefits among other populations, as well as to monitor for adverse effects.
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Affiliation(s)
- Lao-Tzu Allan-Blitz
- Division of Global Health Equity, Department of Medicine, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, 02115, USA.
- Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Kenneth H Mayer
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- The Fenway Institute of Fenway Health, Boston, MA, USA
- Division of Infectious Diseases, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
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3
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Grillová L, Romeis E, Lieberman NAP, Tantalo LC, Xu LH, Molini B, Trejos AT, Lacey G, Goulding D, Thomson NR, Greninger AL, Giacani L. Bright New Resources for Syphilis Research: Genetically Encoded Fluorescent Tags for Treponema pallidum and Sf1Ep Cells. Mol Microbiol 2024; 122:455-464. [PMID: 39115038 PMCID: PMC11479824 DOI: 10.1111/mmi.15304] [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: 05/29/2024] [Revised: 07/18/2024] [Accepted: 07/20/2024] [Indexed: 10/17/2024]
Abstract
The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum (T. pallidum) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted green fluorescent protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum, better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes.
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Affiliation(s)
- Linda Grillová
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, UK
| | - Emily Romeis
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Nicole A P Lieberman
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Lauren C Tantalo
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Linda H Xu
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Barbara Molini
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Aldo T Trejos
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - George Lacey
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, UK
| | - David Goulding
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, UK
| | - Nicholas R Thomson
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, UK
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Alexander L Greninger
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Lorenzo Giacani
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
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Salomè S, Cambriglia MD, Montesano G, Capasso L, Raimondi F. Congenital Syphilis: A Re-Emerging but Preventable Infection. Pathogens 2024; 13:481. [PMID: 38921779 PMCID: PMC11206692 DOI: 10.3390/pathogens13060481] [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: 04/28/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/27/2024] Open
Abstract
Congenital syphilis presents a significant global burden, contributing to fetal loss, stillbirth, neonatal mortality, and congenital infection. Despite the target established in 2007 by the World Health Organization (WHO) of fewer than 50 cases per 100,000 live births, the global incidence is on the rise, particularly in low- and middle-income regions. Recent data indicate a rate of 473 cases per 100,000 live births, resulting in 661,000 total cases of congenital syphilis, including 355,000 adverse birth outcomes such as early fetal deaths, stillbirths, neonatal deaths, preterm or low-birth-weight births, and infants with clinical congenital syphilis. Alarmingly, only 6% of these adverse outcomes occurred in mothers who were enrolled, screened, and treated. Unlike many neonatal infections, congenital syphilis is preventable through effective antenatal screening and treatment of infected pregnant women. However, despite available screening tools, affordable treatment options, and the integration of prevention programs into antenatal care in various countries, congenital syphilis remains a pressing public health concern worldwide. This review aims to summarize the current epidemiology, transmission, and treatment of syphilis in pregnancy, as well as to explore global efforts to reduce vertical transmission and address the reasons for falling short of the WHO elimination target.
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Affiliation(s)
- Serena Salomè
- Division of Neonatology, Department of Translational Medical Sciences, University of Naples Federico II, Via Pansini 5, 80131 Naples, Italy; (M.D.C.); (G.M.); (L.C.); (F.R.)
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Grillová L, Romeis E, Lieberman NAP, Tantalo LC, Xu LH, Molini B, Trejos AT, Lacey G, Goulding D, Thomson NR, Greninger AL, Giacani L. Bright New Resources for Syphilis Research: Genetically Encoded Fluorescent Tags for Treponema pallidum and Sf1Ep Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596454. [PMID: 38854070 PMCID: PMC11160695 DOI: 10.1101/2024.05.29.596454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum ( T. pallidum ) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted Green Fluorescent Protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum , better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes. Graphical abstract By employing genetic engineering, T. pallidum was modified to express GFP, and Sf1Ep cells to express mCherry on the cytoplasmic membrane and BFP in the nucleus. These new resources for syphilis research will facilitate experimental designs to better define the complex interplay between T. pallidum and the host during infection.
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Thapa R, Pandey P, Parat MO, Gurung S, Parekh HS. Phase transforming in situ gels for sustained and controlled transmucosal drug delivery via the intravaginal route. Int J Pharm 2024; 655:124054. [PMID: 38548071 DOI: 10.1016/j.ijpharm.2024.124054] [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: 02/14/2024] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/01/2024]
Abstract
Direct, reliable, controlled, and sustained drug delivery to female reproductive tract (FRT) remains elusive, with conventional dosage forms falling way short of the mark, leading to premature leakage, erratic drug delivery, and loss of compliance. Historically, the intravaginal route remains underserved by the pharmaceutical sector. To comprehensively address this, we turned our focus to phase-transforming sol-gels, using poloxamers, a thermosensitive polymer and, doxycycline (as hyclate salt, DOXH) as our model agent given its potential use in sexually transmitted infections (STIs). We further enhanced mucoadhesiveness through screening of differing viscosity grade hydroxypropyl methyl celluloses (HPMCs). The optimised sol-gels remained gelled at body temperature (<37 °C) and were prepared in buffer aligned to vaginal cavity pH and osmolality. Lead formulations were progressed based on their ability to retain key rheological properties, and acidic pH in the presence of simulated vaginal fluid (SVF). From a shelf-life perspective, DOXH stability, gelation temperature (Tsol-gel), and pH to three months (2-8 °C) was attained. In summary, the meticulously engineered, phase-transforming sol-gels provided sustained mucoretention despite dilution by vaginal fluid, paving the way for localised antimicrobial drug delivery at concentrations that potentially far exceed the minimum inhibitory concentration (MIC) for target STI-causing bacteria of the FRT.
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Affiliation(s)
- Ritu Thapa
- School of Pharamcy, The University of Queensland, 20 Cornwall St, Woollongabba, QLD 4102, Australia
| | - Preeti Pandey
- School of Pharamcy, The University of Queensland, 20 Cornwall St, Woollongabba, QLD 4102, Australia.
| | - Marie-Odile Parat
- School of Pharamcy, The University of Queensland, 20 Cornwall St, Woollongabba, QLD 4102, Australia
| | - Shila Gurung
- School of Health and Allied Sciences, Pokhara University, Pokhara-30, Kaski 33700, Nepal
| | - Harendra S Parekh
- School of Pharamcy, The University of Queensland, 20 Cornwall St, Woollongabba, QLD 4102, Australia.
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Haaland RE, Fountain J, Edwards TE, Dinh C, Martin A, Omoyege D, Conway-Washington C, Kelley CF, Heneine W. Pharmacokinetics of single dose doxycycline in the rectum, vagina, and urethra: implications for prevention of bacterial sexually transmitted infections. EBioMedicine 2024; 101:105037. [PMID: 38428259 PMCID: PMC10910237 DOI: 10.1016/j.ebiom.2024.105037] [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: 07/20/2023] [Revised: 02/08/2024] [Accepted: 02/13/2024] [Indexed: 03/03/2024] Open
Abstract
BACKGROUND Clinical trials showed a single oral dose of doxycycline taken after sex protects against STIs among men who have sex with men (MSM) but not women. Pharmacokinetic data at vaginal, rectal and penile sites of STI exposure are lacking. We examined vaginal, rectal and urethral doxycycline concentrations in men and women to better inform STI prevention. METHODS Doxycycline pharmacokinetics in male and female participants 18-59 years of age were evaluated in blood and urine and on rectal and vaginal swabs collected at 1, 2, 4, 8, 24, 48, 72, 96 and 168 h after receiving a 200 mg oral doxycycline dose in a non-randomised single dose open label single centre study in Atlanta, Georgia. Rectal, vaginal, and cervical biopsies and male urethral swabs were collected 24 h after dosing (Trial registration: NCT04860505). Doxycycline was measured by liquid chromatography-mass spectrometry. FINDINGS Eleven male and nine female participants participated in the study. Doxycycline concentrations on rectal and vaginal swabs collected up to 96 h after dosing were approximately twice those of plasma and remained above minimum inhibitory concentrations (MICs) for at least four, three, and two days for Chlamydia trachomatis, Treponema pallidum, and tetracycline-sensitive Neisseria gonorrhoeae, respectively. Geometric mean doxycycline concentrations in male urethral secretions (1.166 μg/mL; 95% CI 0.568-2.394 μg/mL), male rectal (0.596 μg/g; 0.442-0.803 μg/g), vaginal (0.261 μg/g; 0.098-0.696 μg/g) and cervical tissue (0.410 μg/g; 0.193-0.870 μg/g) in biopsies collected 24 h after dosing exceeded MICs. Plasma and urine doxycycline levels defined adherence markers up to four and seven days postdosing, respectively. No adverse events were reported in this study. INTERPRETATION Doxycycline efficiently distributes to the rectum, vagina and urethra. Findings can help explain efficacy of STI prevention by doxycycline. FUNDING Funded by CDC intramural funds, CDC contract HCVJCG-2020-45044 (to CFK).
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Affiliation(s)
- Richard E Haaland
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Jeffrey Fountain
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Tiancheng E Edwards
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Chuong Dinh
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Amy Martin
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Deborah Omoyege
- The Hope Clinic of the Emory Vaccine Center, Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Christopher Conway-Washington
- The Hope Clinic of the Emory Vaccine Center, Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Colleen F Kelley
- The Hope Clinic of the Emory Vaccine Center, Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA; Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Walid Heneine
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
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Xiong S, Liu Z, Zhang X, Huang S, Ding X, Zhou J, Yao J, Li W, Liu S, Zhao F. Resurgence of syphilis: focusing on emerging clinical strategies and preclinical models. J Transl Med 2023; 21:917. [PMID: 38105236 PMCID: PMC10726518 DOI: 10.1186/s12967-023-04685-4] [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: 07/02/2023] [Accepted: 10/30/2023] [Indexed: 12/19/2023] Open
Abstract
Syphilis, a sexually transmitted disease (STD) caused by Treponema pallidum (T. pallidum), has had a worldwide resurgence in recent years and remains a public health threat. As such, there has been a great deal of research into clinical strategies for the disease, including diagnostic biomarkers and possible strategies for treatment and prevention. Although serological testing remains the predominant laboratory diagnostic method for syphilis, it is worth noting that investigations pertaining to the DNA of T. pallidum, non-coding RNAs (ncRNAs), chemokines, and metabolites in peripheral blood, cerebrospinal fluid, and other bodily fluids have the potential to offer novel perspectives on the diagnosis of syphilis. In addition, the global spread of antibiotic resistance, such as macrolides and tetracyclines, has posed significant challenges for the treatment of syphilis. Fortunately, there is still no evidence of penicillin resistance. Hence, penicillin is the recommended course of treatment for syphilis, whereas doxycycline, tetracycline, ceftriaxone, and amoxicillin are viable alternative options. In recent years, efforts to discover a vaccine for syphilis have been reignited with better knowledge of the repertoire of T. pallidum outer membrane proteins (OMPs), which are the most probable syphilis vaccine candidates. However, research on therapeutic interventions and vaccine development for human subjects is limited due to practical and ethical considerations. Thus, the preclinical model is ideal for conducting research, and it plays an important role in clinical transformation. Different preclinical models have recently emerged, such as in vitro culture and mouse models, which will lay a solid foundation for clinical treatment and prevention of syphilis. This review aims to provide a comprehensive summary of the most recent syphilis tactics, including detection, drug resistance treatments, vaccine development, and preclinical models in clinical practice.
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Affiliation(s)
- Shun Xiong
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Zhaoping Liu
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Xiaohong Zhang
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Shaobin Huang
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Xuan Ding
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Jie Zhou
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Jiangchen Yao
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Weiwei Li
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China
| | - Shuangquan Liu
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China.
- Department of Clinical Laboratory Medicine, The First Affiliated Hospital, Institution of Microbiology and Infectious Diseases, Hengyang Medical College, University of South China, Hengyang, 421001, China.
| | - Feijun Zhao
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan Province, Hengyang Medical College, University of South China, Hengyang, 421001, China.
- Department of Clinical Laboratory Medicine, The First Affiliated Hospital, Institution of Microbiology and Infectious Diseases, Hengyang Medical College, University of South China, Hengyang, 421001, China.
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Tantalo LC, Lieberman NAP, Pérez-Mañá C, Suñer C, Vall Mayans M, Ubals M, González-Beiras C, Rodríguez-Gascón A, Canut A, González-Candelas F, Mueller J, Tapia K, Greninger AL, Giacani L, Mitjà O. Antimicrobial susceptibility of Treponema pallidum subspecies pallidum: an in-vitro study. THE LANCET. MICROBE 2023; 4:e994-e1004. [PMID: 37827185 PMCID: PMC10686905 DOI: 10.1016/s2666-5247(23)00219-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 07/08/2023] [Accepted: 07/13/2023] [Indexed: 10/14/2023]
Abstract
BACKGROUND The increasing incidence of syphilis and the limitations of first-line treatment with penicillin, particularly in neurosyphilis, neonatal syphilis, and pregnancy, highlight the need to expand the therapeutic repertoire for effective management of this disease. We assessed the in-vitro efficacy of 18 antibiotics from several classes on Treponema pallidum subspecies pallidum (T pallidum), the syphilis bacteria. METHODS Using the in-vitro culture system for T pallidum, we exposed the pathogen to a concentration range of each tested antibiotic. After a 7-day incubation, the treponemal burden was evaluated by quantitative PCR targeting the T pallidum tp0574 gene. The primary outcome was the minimum inhibitory concentration (MIC) at which the quantitative PCR values were not significantly higher than the inoculum wells. We also investigated the susceptibility of macrolide-resistant strains to high concentrations of azithromycin, and the possibility of developing resistance to linezolid, a proposed candidate for syphilis treatment. FINDINGS Amoxicillin, ceftriaxone, several oral cephalosporins, tedizolid, and dalbavancin exhibited anti-treponemal activity at concentrations achievable in human plasma following regular dosing regimens. The experiments revealed a MIC for amoxicillin at 0·02 mg/L, ceftriaxone at 0·0025 mg/L, cephalexin at 0·25 mg/L, cefetamet and cefixime at 0·0313 mg/L, cefuroxime at 0·0156 mg/L, tedizolid at 0·0625 mg/L, spectinomycin at 0·1 mg/L, and dalbavancin at 0·125 mg/L. The MIC for zoliflodacin and balofloxacin was 2 mg/L. Ertapenem, isoniazid, pyrazinamide, and metronidazole had either a poor or no effect. Azithromycin concentrations up to 2 mg/L (64 times the MIC) were ineffective against strains carrying mutations associated to macrolide resistance. Exposure to subtherapeutic doses of linezolid for 10 weeks did not induce phenotypic or genotypic resistance. INTERPRETATION Cephalosporins and oxazolidinones are potential candidates for expanding the current therapeutic repertoire for syphilis. Our findings warrant testing efficacy in animal models and, if successful, clinical assessment of efficacy. FUNDING European Research Council.
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Affiliation(s)
- Lauren C Tantalo
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Nicole A P Lieberman
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Clara Pérez-Mañá
- Clinical Pharmacology Unit, Hospital Universitari Germans Trias i Pujol, Institut de Recerca Germans Trias i Pujol, Badalona, Spain; Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Clara Suñer
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Barcelona, Spain; Universitat de Vic-Universitat Central de Catalunya, Vic, Spain
| | - Marti Vall Mayans
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Barcelona, Spain
| | - Maria Ubals
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Barcelona, Spain
| | - Camila González-Beiras
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Barcelona, Spain
| | - Alicia Rodríguez-Gascón
- Pharmacokinetic, Nanotechnology, and Gene Therapy Group (PharmaNanoGene), Faculty of Pharmacy, University of the Basque Country UPV/EHU, Vitoria-Gasteiz, Spain; Bioaraba, Microbiology, Infectious Disease, Antimicrobial Agents, and Gene Therapy Group, Vitoria-Gasteiz, Spain
| | - Andrés Canut
- Bioaraba, Microbiology, Infectious Disease, Antimicrobial Agents, and Gene Therapy Group, Vitoria-Gasteiz, Spain; Microbiology Service, Araba University Hospital, Osakidetza Basque Health Service, Vitoria-Gasteiz, Spain
| | - Fernando González-Candelas
- Joint Research Unit Infection and Public Health, FISABIO-Universitat de València, València, Spain; Institute for Integrative Systems Biology, Universitat de València-CSIC, Paterna, Spain; CIBER Epidemiology and Public Health, Madrid, Spain
| | - John Mueller
- Innoviva Specialty Therapeutics, Waltham, MA, USA
| | - Kenneth Tapia
- Department of Medicine, Division of Allergy and Infectious Diseases, and Department of Global Health, University of Washington, Seattle, WA, USA
| | - Alexander L Greninger
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA; Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Lorenzo Giacani
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA; Department of Medicine, Division of Allergy and Infectious Diseases, and Department of Global Health, University of Washington, Seattle, WA, USA.
| | - Oriol Mitjà
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Barcelona, Spain; Universitat de Vic-Universitat Central de Catalunya, Vic, Spain; School of Medicine and Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea
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Mitjà O, Suñer C, Giacani L, Vall-Mayans M, Tiplica GS, Ross JD, Bradshaw CS. Treatment of bacterial sexually transmitted infections in Europe: gonorrhoea, Mycoplasma genitalium, and syphilis. THE LANCET REGIONAL HEALTH. EUROPE 2023; 34:100737. [PMID: 37927440 PMCID: PMC10625009 DOI: 10.1016/j.lanepe.2023.100737] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/09/2023] [Accepted: 09/12/2023] [Indexed: 11/07/2023]
Abstract
This review explores the therapeutic challenges of sexually transmitted infections (STI) in Europe, which include increasing antimicrobial resistance and limited progress in drug discovery. We primarily focus on gonorrhoea, Mycoplasma genitalium, and syphilis infections. For gonorrhoea with escalating resistance rates we explore the possibility of combining ceftriaxone with another antibiotic or using alternative antibiotics to mitigate resistance emergence, and we provide insights on the ongoing evaluation of new antimicrobials, like gepotidacin and zoliflodacin. In the case of M. genitalium, which exhibits high resistance rates to first and second-line treatments, we emphasize the importance of resistance-guided therapy in regions with elevated resistance levels, and highlight the limited alternative options, such as pristinamycin and minocycline. Furthermore, we address the challenges posed by syphilis, where the primary treatment consists of penicillin or doxycycline, with challenges arising in neurosyphilis, allergy, pregnancy, and supply shortages and discuss the ongoing evaluation of alternative antimicrobials (e.g., ceftriaxone, cefixime, linezolid). Our findings identify priority actions and provide concrete solutions for long-term effective management of STIs and antimicrobial resistance mitigation.
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Affiliation(s)
- Oriol Mitjà
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Badalona, Spain
- Universitat de Vic-Universitat Central de Catalunya, Vic, Spain
- Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Clara Suñer
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Badalona, Spain
- Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Lorenzo Giacani
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA, United States of America
- Department of Global Health, University of Washington, Seattle, WA, United States of America
| | - Martí Vall-Mayans
- Sexually Transmitted Infections and Skin Neglected Tropical Diseases Section, Fight Infectious Diseases Foundation, Hospital Germans Trias i Pujol, Badalona, Spain
| | - George-Sorin Tiplica
- Dermatology 2, Colentina Clinical Hospital, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Jonathan D.C. Ross
- Sexual Health and HIV, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Catriona S. Bradshaw
- Melbourne Sexual Health Centre, Alfred Health, Melbourne, VIC, Australia
- Central Clinical School, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
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11
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Li S, Li W, Jin Y, Wu B, Wu Y. Advancements in the development of nucleic acid vaccines for syphilis prevention and control. Hum Vaccin Immunother 2023; 19:2234790. [PMID: 37538024 PMCID: PMC10405752 DOI: 10.1080/21645515.2023.2234790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 06/12/2023] [Accepted: 07/05/2023] [Indexed: 08/05/2023] Open
Abstract
Syphilis, a chronic systemic sexually transmitted disease, is caused by the bacterium Treponema pallidum (T. pallidum). Currently, syphilis remains a widespread infectious disease with significant disease burden in many countries. Despite the absence of identified penicillin-resistant strains, challenges in syphilis treatment persist due to penicillin allergies, supply issues, and the emergence of macrolide-resistant strains. Vaccines represent the most cost-effective strategy to prevent and control the syphilis epidemic. In light of the ongoing global coronavirus disease 2019 (COVID-19) pandemic, nucleic acid vaccines have gained prominence in the field of vaccine research and development, owing to their superior efficiency compared to traditional vaccines. This review summarizes the current state of the syphilis epidemic and the preliminary findings in T. pallidum nucleic acid vaccine research, discusses the challenges associated with the development of T. pallidum nucleic acid vaccines, and proposes strategies and measures for future T. pallidum vaccine development.
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Affiliation(s)
- Sijia Li
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, Institution of Pathogenic Biology, University of South China, Hengyang, China
| | - Weiwei Li
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, Institution of Pathogenic Biology, University of South China, Hengyang, China
- Department of Clinical Laboratory, The Second People’s Hospital of Foshan, Foshan, China
| | - Yinqi Jin
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, Institution of Pathogenic Biology, University of South China, Hengyang, China
| | - Bin Wu
- First Affiliated Hospital, Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Yimou Wu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang Medical College, Institution of Pathogenic Biology, University of South China, Hengyang, China
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12
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Hayes KA, Dressler JM, Norris SJ, Edmondson DG, Jutras BL. A large screen identifies beta-lactam antibiotics which can be repurposed to target the syphilis agent. NPJ ANTIMICROBIALS AND RESISTANCE 2023; 1:4. [PMID: 38686211 PMCID: PMC11057208 DOI: 10.1038/s44259-023-00006-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/09/2023] [Indexed: 05/02/2024]
Abstract
Syphilis, caused by the spirochete Treponema pallidum subsp. pallidum (hereafter called T. pallidum), is re-emerging as a worldwide sexually transmitted infection. A single intramuscular dose of benzathine penicillin G is the preferred syphilis treatment option. Both supply shortage concerns and the potential for acquired antibiotic resistance further the need to broaden the repertoire of syphilis therapeutics. We reasoned that other β-lactams may be equally or more effective at targeting the disease-causing agent, Treponema pallidum, but have yet to be discovered due to a previous lack of a continuous in vitro culture system. Recent technical advances with respect to in vitro T. pallidum propagation allowed us to conduct a high-throughput screen of almost 100 β-lactams. Using several molecular and cellular approaches that we developed or adapted, we identified and confirmed the efficacy of several β-lactams that were similar to or outperformed the current standard, benzathine penicillin G. These options are either currently used to treat bacterial infections or are synthetic derivatives of naturally occurring compounds. Our studies not only identified additional potential therapeutics in the resolution of syphilis, but provide techniques to study the complex biology of T. pallidum-a spirochete that has plagued human health for centuries.
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Affiliation(s)
- Kathryn A. Hayes
- Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA 24061 USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061 USA
| | - Jules M. Dressler
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061 USA
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061 USA
| | - Steven J. Norris
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, TX USA
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX USA
| | - Diane G. Edmondson
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, TX USA
| | - Brandon L. Jutras
- Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA 24061 USA
- Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061 USA
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061 USA
- Center for Emerging, Zoonotic and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, VA 24061 USA
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13
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Leimer N, Wu X, Imai Y, Morrissette M, Pitt N, Favre-Godal Q, Iinishi A, Jain S, Caboni M, Leus IV, Bonifay V, Niles S, Bargabos R, Ghiglieri M, Corsetti R, Krumpoch M, Fox G, Son S, Klepacki D, Polikanov YS, Freliech CA, McCarthy JE, Edmondson DG, Norris SJ, D'Onofrio A, Hu LT, Zgurskaya HI, Lewis K. A selective antibiotic for Lyme disease. Cell 2021; 184:5405-5418.e16. [PMID: 34619078 DOI: 10.1016/j.cell.2021.09.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/22/2021] [Accepted: 09/08/2021] [Indexed: 12/11/2022]
Abstract
Lyme disease is on the rise. Caused by a spirochete Borreliella burgdorferi, it affects an estimated 500,000 people in the United States alone. The antibiotics currently used to treat Lyme disease are broad spectrum, damage the microbiome, and select for resistance in non-target bacteria. We therefore sought to identify a compound acting selectively against B. burgdorferi. A screen of soil micro-organisms revealed a compound highly selective against spirochetes, including B. burgdorferi. Unexpectedly, this compound was determined to be hygromycin A, a known antimicrobial produced by Streptomyces hygroscopicus. Hygromycin A targets the ribosomes and is taken up by B. burgdorferi, explaining its selectivity. Hygromycin A cleared the B. burgdorferi infection in mice, including animals that ingested the compound in a bait, and was less disruptive to the fecal microbiome than clinically relevant antibiotics. This selective antibiotic holds the promise of providing a better therapeutic for Lyme disease and eradicating it in the environment.
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Affiliation(s)
- Nadja Leimer
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Xiaoqian Wu
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Yu Imai
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Madeleine Morrissette
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Norman Pitt
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Quentin Favre-Godal
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Akira Iinishi
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Samta Jain
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Mariaelena Caboni
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Inga V Leus
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
| | - Vincent Bonifay
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
| | - Samantha Niles
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Rachel Bargabos
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Meghan Ghiglieri
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Rachel Corsetti
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Megan Krumpoch
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Gabriel Fox
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Sangkeun Son
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Dorota Klepacki
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Yury S Polikanov
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Cecily A Freliech
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, MA 02111, USA
| | - Julie E McCarthy
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, MA 02111, USA
| | - Diane G Edmondson
- Department of Pathology and Laboratory Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77225, USA
| | - Steven J Norris
- Department of Pathology and Laboratory Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77225, USA
| | - Anthony D'Onofrio
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA
| | - Linden T Hu
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, MA 02111, USA
| | - Helen I Zgurskaya
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
| | - Kim Lewis
- Antimicrobial Discovery Center, Department of Biology, Northeastern University, Boston, MA 02115, USA.
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14
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Ikeuchi K, Fukushima K, Tanaka M, Yajima K, Imamura A. Clinical efficacy and tolerability of 1.5 g/day oral amoxicillin therapy without probenecid for the treatment of syphilis. Sex Transm Infect 2021; 98:173-177. [PMID: 33782148 DOI: 10.1136/sextrans-2020-054823] [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: 10/06/2020] [Revised: 03/08/2021] [Accepted: 03/12/2021] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES Intramuscular benzathine penicillin G is not available in certain countries. In a previous report, 3 g/day amoxicillin with probenecid was shown to be effective in treating syphilis in patients with HIV; however, 7.3% of patients changed their therapy owing to adverse events. The objective of this study was to assess the clinical efficacy and tolerability of 1.5 g/day amoxicillin without probenecid for the treatment of syphilis. METHODS The routine clinical records of patients diagnosed with syphilis and treated with 1.5 g/day amoxicillin at a tertiary care hospital between 2006 and 2018 were retrospectively analysed. Syphilis was diagnosed if serum rapid plasma reagin (RPR) titres were ≥8 RU and the Treponema pallidum latex-agglutination test was positive. Serological cure was defined as a ≥fourfold decrease in the RPR titre within 12 months in symptomatic early syphilis and within 24 months in latent syphilis. RESULTS Overall, 138 patients (112 with HIV) were analysed. The percentages of primary, secondary, early latent, late latent and latent syphilis of unknown duration were 8.0%, 50.0%, 25.4%, 5.8% and 10.9%, respectively. The median treatment duration was 4.5 weeks (IQR 4-8 weeks), which was not related to the stage of syphilis. Two patients (1.5%) changed treatment due to skin rash. The rate of serological cure was 94.9% (131/138; 95% CI 89.8% to 97.9%) overall; 93.8% (105/112; 95% CI 87.5% to 97.5%) in patients with HIV and 100% (26/26; 95% CI 86.8% to 100%) in patients without HIV. Treatment duration was not related to the treatment efficacy. CONCLUSION The regimen of 1.5 g/day amoxicillin without probenecid is highly effective with a low switch rate in patients with and without HIV.
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Affiliation(s)
- Kazuhiko Ikeuchi
- Department of Infectious Diseases, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Japan
| | - Kazuaki Fukushima
- Department of Infectious Diseases, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Japan
| | - Masaru Tanaka
- Department of Infectious Diseases, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Japan
| | - Keishiro Yajima
- Department of Infectious Diseases, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Japan
| | - Akifumi Imamura
- Department of Infectious Diseases, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Japan
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Edmondson DG, DeLay BD, Kowis LE, Norris SJ. Parameters Affecting Continuous In Vitro Culture of Treponema pallidum Strains. mBio 2021; 12:e03536-20. [PMID: 33622721 PMCID: PMC8545124 DOI: 10.1128/mbio.03536-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 01/12/2021] [Indexed: 11/20/2022] Open
Abstract
The bacterium that causes syphilis, Treponema pallidum subsp. pallidum, has now been cultured in vitro continuously for periods exceeding 3 years using a system consisting of coculture with Sf1Ep rabbit epithelial cells in TpCM-2 medium and a low-oxygen environment. In addition, long-term culture of several other syphilis isolates (SS14, Mexico A, UW231B, and UW249B) and the T. pallidum subsp. endemicum Bosnia A strain has been achieved. During in vitro passage, T. pallidum subsp. pallidum exhibited a typical bacterial growth curve with logarithmic and stationary phases. Sf1Ep cells are required for sustained growth and motility; however, high initial Sf1Ep cell numbers resulted in reduced multiplication and survival. Use of Eagle's minimal essential medium as the basal medium was not effective in sustaining growth of T. pallidum subsp. pallidum beyond the first passage, whereas CMRL 1066 or M199 supported long-term culture, confirming that additional nutrients present in these more complex basal media are required for long-term culture. T. pallidum subsp. pallidum growth was dependent upon the presence of fetal bovine serum, with 20% (vol/vol) being the optimal concentration. Omission of reactive oxygen species scavengers dithiothreitol, d-mannitol, or l-histidine did not dramatically affect survival or growth. Additionally, T. pallidum subsp. pallidum can be successfully cultured in a Brewer jar instead of a specialized low-oxygen incubator. Phosphomycin or amphotericin B can be added to the medium to aid in the prevention of bacterial or fungal contamination, respectively. These results help define the parameters of the T. pallidum subsp. pallidum culture system that are required for sustained, long-term survival and multiplication.IMPORTANCE Syphilis is caused by the bacterium Treponema pallidum subsp. pallidum Until recently, this pathogen could only be maintained through infection of rabbits or other animals, making study of this important human pathogen challenging and costly. T. pallidum subsp. pallidum has now been successfully cultured for over 3 years in a tissue culture system using a medium called TpCM-2. Here, we further define the growth requirements of this important human pathogen, promoting a better understanding of the biology of this fastidious organism.
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Affiliation(s)
- Diane G Edmondson
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Bridget D DeLay
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Lindsay E Kowis
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Steven J Norris
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
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Wormser GP, Warshafsky S, Visintainer P. Aggregation of data from 4 clinical studies demonstrating efficacy of single-dose doxycycline postexposure for prevention of the spirochetal infections: Lyme disease, syphilis, and tick-borne relapsing fever. Diagn Microbiol Infect Dis 2020; 99:115293. [PMID: 33360515 DOI: 10.1016/j.diagmicrobio.2020.115293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 11/30/2022]
Abstract
Single-dose doxycycline, given within 72 hours of exposure, has been evaluated in 4 clinical studies for postexposure prophylaxis of 3 spirochetal infections: Lyme disease, syphilis, and tick-borne relapsing fever. In this study, data from the 4 studies were aggregated using a meta-analytic random-effects approach, with the DerSimonian-Laird method for variance estimation, analyzing a total of 2468 subjects. The findings of this analysis demonstrated an overall efficacy rate for prevention of the 3 spirochetal infections of 78% (95% confidence interval: 50%-91%).
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Affiliation(s)
- Gary P Wormser
- Division of Infectious Diseases, New York Medical College, Valhalla, NY, USA.
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