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14 pages, 599 KB  
Article
Genotype-Specific Distribution of High-Risk Human Papillomavirus (HPV) and Microbial Co-Detections in HPV-Positive Women from Southern Croatia
by Vanja Kaliterna, Tomislav Meštrović, Mirjana Čorić-Mesarić and Ivana Božičević
Biomedicines 2025, 13(9), 2100; https://doi.org/10.3390/biomedicines13092100 - 28 Aug 2025
Viewed by 202
Abstract
Background/Objectives: High-risk human papillomavirus (HPV) is the principal etiological agent of cervical cancer, with distinct genotype-specific oncogenic potential. While HPV type 16 is most frequently implicated in carcinogenesis, the role of other genotypes and their interaction with sexually transmitted infections and cervico-vaginal [...] Read more.
Background/Objectives: High-risk human papillomavirus (HPV) is the principal etiological agent of cervical cancer, with distinct genotype-specific oncogenic potential. While HPV type 16 is most frequently implicated in carcinogenesis, the role of other genotypes and their interaction with sexually transmitted infections and cervico-vaginal dysbiosis is gaining recognition. This study aimed to assess the genotype-specific distribution of high-risk HPV among HPV-positive women from Southern Croatia and examine associations with age and co-infections with selected microbial pathogens. Methods: We conducted a retrospective cross-sectional study on 1211 HPV-positive women (out of 3098 tested) from Split and Dalmatia County between 2023 and 2024. Cervico-vaginal swabs were tested using molecular and culture-based methods for 14 high-risk HPV genotypes and several pathogens, including Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, Gardnerella vaginalis, and other microorganisms. In the analysis, each detected HPV genotype was also treated as a distinct line-level observation. Genotypes were grouped by phylogenetic and carcinogenic profiles, and statistical analyses—including chi-square tests and multinomial logistic regression—were performed to evaluate associations with age and co-infections. Results: Among high-risk HPV-positive women, the most frequently detected high-risk HPV genotypes were HPV 16 (23.3%), HPV 31 (22.4%), and HPV 51 (13.5%). Notably, HPV 18 was less prevalent (8.1%) and occurred at a similar frequency to HPV 58 and 68. Although younger age was significantly associated with high-risk HPV positivity (p < 0.001), no significant differences in HPV genotype group distribution were observed between age groups; however, C. trachomatis and Streptococcus agalactiae were significantly more prevalent in women aged ≤29 years (p < 0.001 and p = 0.029, respectively). Multinomial regression revealed that C. trachomatis was negatively associated with 16-related and lower-risk genotypes, while G. vaginalis showed a positive association with 16-related types. Conclusions: There is a complex interplay between high-risk HPV genotypes and microbial co-infections, which means the broader cervico-vaginal microbiome has to be considered in HPV risk assessment. The findings highlight the need for extended genotyping and microbial screening to inform regional prevention strategies. Full article
(This article belongs to the Special Issue Current Perspectives on Human Papillomavirus (HPV))
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11 pages, 380 KB  
Article
Sexually Transmitted Infections: Usefulness of Molecular Methods for Microorganism Detection in Stored Sexual Assault Samples
by Laura Cainé, Ana Eira, Jennifer Fadoni, Magda Franco, Helena Correia Dias and António Amorim
Int. J. Mol. Sci. 2025, 26(17), 8124; https://doi.org/10.3390/ijms26178124 - 22 Aug 2025
Viewed by 146
Abstract
Sexual assault is a global public health and human rights concern, with serious physical, psychological and reproductive consequences for survivors. Among these, sexually transmitted infections are particularly relevant due to their frequently asymptomatic nature and potential for long-term complications. The detection of sexually [...] Read more.
Sexual assault is a global public health and human rights concern, with serious physical, psychological and reproductive consequences for survivors. Among these, sexually transmitted infections are particularly relevant due to their frequently asymptomatic nature and potential for long-term complications. The detection of sexually transmitted infections in forensic settings is crucial for clinical management of victims and for evidentiary support in forensic sexual crimes investigations. This study aimed to evaluate the applicability of real-time polymerase chain reaction for detecting Chlamydia trachomatis, Trichomonas vaginalis, Neisseria gonorrhoeae, and Treponema pallidum in biological samples collected from victims of sexual assault and stored under routine forensic conditions, in some cases, for up to 18 years. A total of 231 swabs from 116 individuals collected between 2004 and 2017 were analysed using real-time PCR with pathogen-specific primers and fluorescent probes. The analysis revealed 13 positive samples of T. vaginalis (5.6%) and 11 of C. trachomatis (4.8%). No positive results were obtained for N. gonorrhoeae or T. pallidum. These findings demonstrate the usefulness of real-time polymerase chain reaction for detecting sexually transmitted infections in long-term preserved forensic samples. Moreover, the ability to identify pathogen DNA in archived samples highlights the potential role of molecular diagnostics in the retrospective investigation of sexual crimes, including cold cases. It underscores the value of molecular methods as a complementary tool in forensic proceedings and survivor care. Full article
(This article belongs to the Special Issue Molecular Forensics and the Genetic Foundations of Forensic Biology)
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19 pages, 1877 KB  
Article
Abscopal Brain Proteomic Changes Associated with Microbiome Alterations Induced by Gastrointestinal Acute Radiation Syndrome in Swine
by Kathleen Hatch, Timothy S. Horseman, Babita Parajuli, Erin K. Murphy, Robert N. Cole, Robert N. O’Meally, Daniel P. Perl, David M. Burmeister and Diego Iacono
Int. J. Mol. Sci. 2025, 26(17), 8121; https://doi.org/10.3390/ijms26178121 - 22 Aug 2025
Viewed by 205
Abstract
Emerging research highlights the gut microbiota’s critical role in modulating brain activity via the gut–brain axis. This study explores whether targeted gastrointestinal irradiation induces abscopal effects on the brain proteome, revealing microbiota-mediated neurobiological changes. Male Sinclair minipigs were randomized to receive either sham [...] Read more.
Emerging research highlights the gut microbiota’s critical role in modulating brain activity via the gut–brain axis. This study explores whether targeted gastrointestinal irradiation induces abscopal effects on the brain proteome, revealing microbiota-mediated neurobiological changes. Male Sinclair minipigs were randomized to receive either sham treatment (n = 6) or 8 Gy lower hemibody (gut-targeted) irradiation (n = 5). Over 14 days, rectal swabs were collected to monitor microbiota dynamics, followed by frontal cortex proteomic analysis. Irradiation altered gut microbiota composition, notably reducing Chlamydiae and Firmicutes phyla, while increasing Coriobacteriaceae and Acinetobacter. Proteomic analysis identified 75 differentially abundant proteins in the frontal cortex, including a significant decrease in pannexin-1 (PANX1), suggesting modulation of the NLRP3 inflammasome pathway. Functional enrichment analysis revealed immune and neurotransmission-related changes linked to microbial shifts. These results demonstrate that gut-targeted radiation can remotely affect brain protein expression, emphasizing the microbiota’s role in neuroimmune regulation and pointing to novel therapeutic opportunities in gut–brain axis disorders. Full article
(This article belongs to the Special Issue Emerging Roles of the Gut-Brain Axis (GBA) in Health and Disease)
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12 pages, 269 KB  
Article
Chlamydia trachomatis-Specific Antibodies and In Vitro Fertilization Outcome
by Natasa Djordjevic, Ana Todorovic, Predrag Sazdanovic, Maja Sazdanovic, Marija Sorak, Aleksandra Gavrilovic, Aida Parandilovic, Eliana Garalejic, Marija Vujovic, Sanja Matic, Suzana Popovic and Dejan Baskic
Biomedicines 2025, 13(8), 2032; https://doi.org/10.3390/biomedicines13082032 - 20 Aug 2025
Viewed by 448
Abstract
Objectives: Chlamydia trachomatis (CT) infection affects female fertility. The purpose of our study was to assess the association between serological and follicular fluid markers of CT infection and in vitro fertilization (IVF) success. Methods: This prospective multicenter cohort study included female [...] Read more.
Objectives: Chlamydia trachomatis (CT) infection affects female fertility. The purpose of our study was to assess the association between serological and follicular fluid markers of CT infection and in vitro fertilization (IVF) success. Methods: This prospective multicenter cohort study included female patients undergoing an IVF procedure in Serbia. The IVF procedure was performed according to the standard protocol. Serum and follicular fluid samples were collected during IVF, and anti-major outer membrane protein (anti-MOMP) IgG and IgA were determined by the Enzyme-Linked Immunosorbent Assay (ELISA) test. Results: A significantly higher embryo implantation rate was detected among patients negative for antibodies in follicular fluid (OR (95% CI): 5.254 (1.055; 26.152)). There was a trend toward increased risk of IVF failure in patients positive for either IgG or IgA in follicular fluid, or positive for IgG in serum. Older age was associated with lower odds for successful implantation (OR (95% CI): 0.888 (0.820; 0.962)), biochemical pregnancy (OR (95% CI): 0.890 (0.817; 0.969)), and live birth (OR (95% CI): 0.906 (0.833; 0.985)). Conclusions: Our results suggest that the presence of chlamydial anti-MOMP IgG and IgA in the serum and follicular fluid of infertile women could be indicative of lower IVF success rate, and that advanced maternal age is associated with higher risk of IVF failure. Full article
(This article belongs to the Special Issue The Art of ART (Assisted Reproductive Technologies))
13 pages, 301 KB  
Review
The Impact of Genital Infections on Women’s Fertility
by Sara Occhipinti, Carla Ettore, Giosuè Giordano Incognito, Chiara Gullotta, Dalila Incognito, Roberta Foti, Giuseppe Nunnari and Giuseppe Ettore
Acta Microbiol. Hell. 2025, 70(3), 33; https://doi.org/10.3390/amh70030033 - 7 Aug 2025
Viewed by 861
Abstract
Sexually transmitted infections (STIs) are a significant global health concern, affecting millions of people worldwide, particularly sexually active adolescents and young adults. These infections, caused by various pathogens, including bacteria, viruses, parasites, and fungi, can have profound implications for women’s reproductive health and [...] Read more.
Sexually transmitted infections (STIs) are a significant global health concern, affecting millions of people worldwide, particularly sexually active adolescents and young adults. These infections, caused by various pathogens, including bacteria, viruses, parasites, and fungi, can have profound implications for women’s reproductive health and fertility. This review explores the role of vaginal and uterine infections in women’s infertility, focusing on the most common pathogens and their impact on reproductive outcomes. Bacterial infections, such as those caused by intracellular bacteria (Mycoplasma, Ureaplasma, and Chlamydia), Neisseria gonorrhoeae, and bacterial vaginosis, are among the most prevalent causes of infertility in women. Studies have shown that these infections can lead to pelvic inflammatory disease, tubal occlusion, and endometrial damage, all of which can impair fertility. Mycobacterium tuberculosis, in particular, is a significant cause of genital tuberculosis and infertility in high-incidence countries. Viral infections, such as Human papillomavirus (HPV) and Herpes simplex virus (HSV), can also affect women’s fertility. While the exact role of HPV in female infertility remains unclear, studies suggest that it may increase the risk of endometrial implantation issues and miscarriage. HSV may be associated with unexplained infertility. Parasitic infections, such as trichomoniasis and schistosomiasis, can directly impact the female reproductive system, leading to infertility, ectopic pregnancy, and other complications. Fungal infections, such as candidiasis, are common but rarely have serious outcomes related to fertility. The vaginal microbiome plays a crucial role in maintaining reproductive health, and alterations in the microbial balance can increase susceptibility to STIs and infertility. Probiotics have been proposed as a potential therapeutic strategy to restore the vaginal ecosystem and improve fertility outcomes, although further research is needed to establish their efficacy. In conclusion, vaginal and uterine infections contribute significantly to women’s infertility, with various pathogens affecting the reproductive system through different mechanisms. Early diagnosis, appropriate treatment, and preventive measures are essential to mitigate the impact of these infections on women’s reproductive health and fertility. Full article
10 pages, 789 KB  
Communication
Female Sex Workers in the Amazon Region of Brazil Are at High Risk of Chlamydia trachomatis Infection: A Retrospective Study
by Leonardo Gabriel Campelo Pinto de Figueiredo, Paula do Socorro de Oliveira da Costa Laurindo, Daniela Assunção Pantoja, Maurimélia Mesquita da Costa, Diogo Oliveira de Araújo, Felipe Bonfim Freitas, Jacqueline Cortinhas Monteiro, Ricardo Roberto de Souza Fonseca, Rosimar Neris Martins Feitosa, Rogério Valois Laurentino, Leonardo Miranda dos Santos, Aldemir Branco Oliveira-Filho and Luiz Fernando Almeida Machado
Microorganisms 2025, 13(8), 1815; https://doi.org/10.3390/microorganisms13081815 - 3 Aug 2025
Viewed by 8504
Abstract
Background: Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection (STI) globally, linked to severe complications such as pelvic inflammatory disease and infertility. In the Brazilian Amazon, socioeconomic vulnerability and the absence of screening policies exacerbate risks, particularly among female sex workers [...] Read more.
Background: Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection (STI) globally, linked to severe complications such as pelvic inflammatory disease and infertility. In the Brazilian Amazon, socioeconomic vulnerability and the absence of screening policies exacerbate risks, particularly among female sex workers (FSWs). Objective: This study aimed to determine the seroprevalence of anti-C. trachomatis IgG antibodies among FSWs in five municipalities of Pará State, Brazilian Amazon, and identify epidemiological factors associated with infection. Methods: A retrospective cross-sectional study (2005–2007) included 348 FSWs recruited via convenience sampling. Sociodemographic and behavioral data were collected through questionnaires, and blood samples were analyzed by ELISA for anti-C. trachomatis IgG. Statistical analyses included Fisher’s exact tests, odds ratios (ORs), and 95% confidence intervals (CIs), using SPSS 21.0. Results: Overall seroprevalence was 93.9% (327/348; 95% CI: 83.1–90%). Significant associations included a household income of 1–3 minimum wages (98.4%; p = 0.0002), sexual partners from the same region (98.8%; p = 0.0421), and age >42 years (96.3%). Most reported inconsistent condom use (43.7%), multiple monthly partners (54.6%), and illicit drug use (53.4%). Discussion: The extremely high seroprevalence reflects chronic C. trachomatis exposure, driven by socioeconomic deprivation and limited healthcare access. Comparisons with global data underscore the urgent need for screening policies, absent in Brazil for FSWs, and highlight the vulnerability of this population. Conclusions: The findings reveal an alarming burden of C. trachomatis exposure among Amazonian FSWs. Integrated strategies, including routine screening, sexual health education, and inclusion of FSWs in priority health programs, are critical to reduce transmission and associated complications. Full article
(This article belongs to the Special Issue Chlamydiae and Chlamydia-Like Infections)
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12 pages, 3410 KB  
Article
Nasal and Ocular Immunization with Bacteriophage Virus-like Particle Vaccines Elicits Distinct Systemic and Mucosal Antibody Profiles
by Andzoa N. Jamus, Zoe E. R. Wilton, Samantha D. Armijo, Julian Flanagan, Isabella G. Romano, Susan B. Core and Kathryn M. Frietze
Vaccines 2025, 13(8), 829; https://doi.org/10.3390/vaccines13080829 - 3 Aug 2025
Viewed by 566
Abstract
Background/Objectives: Intramuscular immunization elicits systemic IgG and is the primary route of vaccine administration in humans. However, there is growing interest in utilizing other routes of administration to tailor antibody profiles, increase immunity at primary sites of infection, simplify administration, and eliminate [...] Read more.
Background/Objectives: Intramuscular immunization elicits systemic IgG and is the primary route of vaccine administration in humans. However, there is growing interest in utilizing other routes of administration to tailor antibody profiles, increase immunity at primary sites of infection, simplify administration, and eliminate needle waste. Here, we investigated the antibody profiles elicited by immunization with bacteriophage virus-like particle vaccine platforms at various routes of administration. Methods: We chose two model bacteriophage vaccines for investigation: bacteriophage MS2 virus-like particles (VLPs) recombinantly displaying a short, conserved peptide from Chlamydia trachomatis major outer membrane protein (MS2) and bacteriophage Qβ VLPs displaying oxycodone through chemical conjugation (Qβ). We comprehensively characterized the antibodies elicited systemically and at various mucosal sites when the vaccines were administered intramuscularly, intranasally or periocularly with or without an intramuscular prime using various prime/boost schemes. Results: Intranasal and periocular immunization elicited robust mucosal and systemic IgA responses for both MS2 and Qβ. The intramuscular prime followed by intranasal or periocular boosts elicited broad antibody responses, and increased antibodies titers at certain anatomical sites. Conclusions: These findings demonstrate the tractability of bacteriophage VLP-based vaccines in generating specific antibody profiles based on the prime–boost regimen and route of administration. Full article
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23 pages, 23270 KB  
Article
Identifying Infectious Agents in Snakes (Boidae and Pythonidae) with and Without Respiratory Disease
by Marline M. Faulhaber, Florence Tardy, Anne V. Gautier-Bouchardon, Sabine Öfner, Sebastiaan Theuns, Sieglinde Coppens, Elisabeth Müller, Michael Pees and Rachel E. Marschang
Animals 2025, 15(15), 2187; https://doi.org/10.3390/ani15152187 - 25 Jul 2025
Viewed by 763
Abstract
Mycoplasmas are known respiratory pathogens in tortoises, but few studies exist in snakes. To better understand the correlation with clinical signs and co-infections, samples from mycoplasma-positive snakes with and without clinical respiratory disease were analyzed. Oral swabs from 15 snakes (pythons n = [...] Read more.
Mycoplasmas are known respiratory pathogens in tortoises, but few studies exist in snakes. To better understand the correlation with clinical signs and co-infections, samples from mycoplasma-positive snakes with and without clinical respiratory disease were analyzed. Oral swabs from 15 snakes (pythons n = 12, boas n = 3) were examined using polymerase chain reaction (PCR) and third-generation sequencing (TGS). Additionally, mycoplasma isolation assays were performed. Pathogens detected by PCR included Mycoplasmas (15/15, 100%), serpentoviruses (9/15, 60%), and Chlamydia sp. (2/15, 13%); those detected by TGS included Mycoplasmas (14/15, 93%), serpentoviruses (10/15, 67%), Chlamydia sp. (1/15, 7%), and 15 different bacterial species. Sequencing of the mycoplasma PCR products revealed a close genetic relationship to Mycoplasmopsis agassizii. TGS identified genetically distinct mycoplasmas and three different serpentoviruses. While mycoplasmas could not be successfully propagated, Brucella intermedia comb. nov. was identified in eight cultures. Respiratory disease in snakes is often multifactorial, involving various pathogens and environmental influences. This study demonstrates that comprehensive diagnostics are essential for understanding disease processes in snakes and improving the detection of diverse pathogens. Further research is needed to improve laboratory diagnostics for infectious diseases in reptiles and to better understand the roles of various pathogens in respiratory diseases in snakes. Full article
(This article belongs to the Special Issue Advances in Reptile and Amphibian Infectious Diseases)
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14 pages, 5817 KB  
Article
Recent Changes in Sexually Transmitted Infection in Korea: A Population-Based Analysis
by Jae Yen Song, Kang Seob Kim, Chang Hee Han and Sangrak Bae
J. Clin. Med. 2025, 14(14), 5145; https://doi.org/10.3390/jcm14145145 - 20 Jul 2025
Viewed by 1316
Abstract
Background: The objective of this study is to investigate the prevalence and epidemiological changes of major sexually transmitted infections (STIs) in Korea over the past decade. Methods: From 2010 to 2021, patients diagnosed with STIs based on ICD-10 codes were analyzed [...] Read more.
Background: The objective of this study is to investigate the prevalence and epidemiological changes of major sexually transmitted infections (STIs) in Korea over the past decade. Methods: From 2010 to 2021, patients diagnosed with STIs based on ICD-10 codes were analyzed using Korean Health insurance data. The analysis included the number of patients, prevalence, and age-specific prevalence (in 5-year intervals) over this period. We examined changes in disease patterns over time by analyzing the annual trends and age-specific prevalence of bacterial STIs such as chlamydia, mycoplasma, gonorrhea, and syphilis; viral STIs such as genital herpes, human papillomavirus (HPV), and human immunodeficiency virus (HIV); and other infections including scabies, pubic lice, and trichomoniasis. Results: In 2010, the STI with the highest prevalence due to an infectious pathogen was trichomoniasis (256.65/100,000), while latent syphilis had the lowest prevalence (5.29/100,000). In 2021, the STI with the highest prevalence was genital herpes (254.54 per 100,000 persons), and latent syphilis continued to have the lowest prevalence. Bacterial STIs showed a decreasing trend. Viral STIs showed a continuous increase throughout the study period, with anogenital warts (AGW) having the highest rate of increase. Other infections showed a decreasing trend. HIV and AGW in men showed a rapid increase. Gender differences varied depending on the disease. Conclusions: While bacterial STIs have gradually declined, viral STIs have continued to increase during last decade. The characteristics of each pathogen vary according to age and gender, necessitating the establishment of risk groups for each pathogen and the development of prevention policies accordingly. Full article
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19 pages, 1971 KB  
Article
IoMT Architecture for Fully Automated Point-of-Care Molecular Diagnostic Device
by Min-Gin Kim, Byeong-Heon Kil, Mun-Ho Ryu and Jong-Dae Kim
Sensors 2025, 25(14), 4426; https://doi.org/10.3390/s25144426 - 16 Jul 2025
Viewed by 604
Abstract
The Internet of Medical Things (IoMT) is revolutionizing healthcare by integrating smart diagnostic devices with cloud computing and real-time data analytics. The emergence of infectious diseases, including COVID-19, underscores the need for rapid and decentralized diagnostics to facilitate early intervention. Traditional centralized laboratory [...] Read more.
The Internet of Medical Things (IoMT) is revolutionizing healthcare by integrating smart diagnostic devices with cloud computing and real-time data analytics. The emergence of infectious diseases, including COVID-19, underscores the need for rapid and decentralized diagnostics to facilitate early intervention. Traditional centralized laboratory testing introduces delays, limiting timely medical responses. While point-of-care molecular diagnostic (POC-MD) systems offer an alternative, challenges remain in cost, accessibility, and network inefficiencies. This study proposes an IoMT-based architecture for fully automated POC-MD devices, leveraging WebSockets for optimized communication, enhancing microfluidic cartridge efficiency, and integrating a hardware-based emulator for real-time validation. The system incorporates DNA extraction and real-time polymerase chain reaction functionalities into modular, networked components, improving flexibility and scalability. Although the system itself has not yet undergone clinical validation, it builds upon the core cartridge and detection architecture of a previously validated cartridge-based platform for Chlamydia trachomatis and Neisseria gonorrhoeae (CT/NG). These pathogens were selected due to their global prevalence, high asymptomatic transmission rates, and clinical importance in reproductive health. In a previous clinical study involving 510 patient specimens, the system demonstrated high concordance with a commercial assay with limits of detection below 10 copies/μL, supporting the feasibility of this architecture for point-of-care molecular diagnostics. By addressing existing limitations, this system establishes a new standard for next-generation diagnostics, ensuring rapid, reliable, and accessible disease detection. Full article
(This article belongs to the Special Issue Advances in Sensors and IoT for Health Monitoring)
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19 pages, 3486 KB  
Article
3-O Sulfated Heparan Sulfate (G2) Peptide Ligand Impairs the Infectivity of Chlamydia muridarum
by Weronika Hanusiak, Purva Khodke, Jocelyn Mayen, Kennedy Van, Ira Sigar, Balbina J. Plotkin, Amber Kaminski, James Elste, Bajarang Vasant Kumbhar and Vaibhav Tiwari
Biomolecules 2025, 15(7), 999; https://doi.org/10.3390/biom15070999 - 12 Jul 2025
Viewed by 663
Abstract
Background: Heparan sulfate (HS) is widely implicated as a receptor for Chlamydia cell attachment and infectivity. However, the enzymatic modification of HS modified by the 3-O sulfotransferase-3 (3-OST-3) enzyme in chlamydial cell entry remains unknown. Methodology: To rule out the possibility that host [...] Read more.
Background: Heparan sulfate (HS) is widely implicated as a receptor for Chlamydia cell attachment and infectivity. However, the enzymatic modification of HS modified by the 3-O sulfotransferase-3 (3-OST-3) enzyme in chlamydial cell entry remains unknown. Methodology: To rule out the possibility that host cell 3-O sulfated heparan sulfate (3-OS HS) plays a significant role in C. muridarum entry, a Chinese hamster ovary (CHO-K1) cell model lacking endogenous 3-OST-3 was used. In addition, we further tested the efficacy of the phage-display-derived cationic peptides recognizing heparan sulfate (G1 peptide) and the moieties of 3-O sulfated heparan sulfate (G2 peptide) against C. muridarum entry using human cervical adenocarcinoma (HeLa 229) and human vaginal epithelial (VK2/E6E7) cell lines. Furthermore, molecular dynamics simulations were conducted to investigate the interactions of the Chlamydia lipid bilayer membrane with the G1 and G2 peptides, focusing on their binding modes and affinities. Results: The converse effect of 3-OST-3 expression in the CHO-K1 cells had no enhancing effect on C. muridarum entry. The G2 peptide significantly (>80%) affected the cell infectivity of the elementary bodies (EBs) at all the tested concentrations, as evident from the reduced fluorescent staining in the number of inclusion bodies. The observed neutralization effect of G2 peptide on C. muridarum entry suggests the possibility of sulfated-like domains being present on the EBs. In addition, data generated from our in silico computational structural modeling indicated that the G2 peptide ligand had significant affinity towards the C. muridarum lipid bilayer. Conclusions: Taken together, our findings show that the pretreatment of C. muridarum with 3-O sulfated heparan sulfate recognizing G2 peptide significantly prevents the entry of EBs into host cells. Full article
(This article belongs to the Section Chemical Biology)
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9 pages, 845 KB  
Article
Preliminary Evidence of Chlamydiosis in Koalas of the Greater Geelong Region, Victoria: A Potential Emerging Threat?
by Gianna Kramer, Janine Duffy and Valentina S. A. Mella
Animals 2025, 15(14), 2048; https://doi.org/10.3390/ani15142048 - 11 Jul 2025
Viewed by 1469
Abstract
Koalas (Phascolarctos cinereus) face many threats, with one of them being the disease chlamydiosis caused by the bacterium Chlamydia pecorum, a cause for infertility and one of the main causes of population decline. In New South Wales, Queensland, and the [...] Read more.
Koalas (Phascolarctos cinereus) face many threats, with one of them being the disease chlamydiosis caused by the bacterium Chlamydia pecorum, a cause for infertility and one of the main causes of population decline. In New South Wales, Queensland, and the Australian Capital Territory, the koala is an endangered species, but in Victoria, koalas are widespread and overabundant in some areas. The koala populations in the You Yangs Regional Park (YYRP) and Brisbane Ranges National Park (BRNP) in Victoria are reported to be in decline, although there have been no studies looking into population density or disease. The aim of this study was to investigate the presence of C. pecorum in the koala populations of the YYRP and BRNP to understand whether disease may be a cause of concern. DNA was extracted from scats, and qPCR was used to detect the presence and load of C. pecorum. C. pecorum was found in 12/18 (66.7%) scat samples. Clinical signs of disease, age, and sex did not affect infection shedding load. These results confirm the presence of chlamydiosis within the YYRP and BRNP koala populations. More detailed studies are recommended to quantify prevalence of the disease in these populations and to understand the consequences of chlamydiosis in these areas. Full article
(This article belongs to the Special Issue Koalas Management: Ecology and Conservation)
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13 pages, 892 KB  
Article
Comparative Evaluation of Recombinant Chlamydia abortus and Chlamydia trachomatis Major Outer Membrane Proteins for Diagnosing Human Chlamydial Infection
by Fernando M. Guerra-Infante, María J. de Haro-Cruz, Marcela López-Hurtado, Miguel A. De la Rosa-Ramos, Efrén Díaz-Aparicio and Beatriz Arellano-Reynoso
Microbiol. Res. 2025, 16(7), 159; https://doi.org/10.3390/microbiolres16070159 - 9 Jul 2025
Viewed by 417
Abstract
Chlamydia trachomatis infection is a public health problem. Serological tests can determine the disease burden and serve as a biomarker for identifying patients with infertility due to tubal obstruction. However, cross-reactions between chlamydial species have been reported, which causes problems with diagnosis. A [...] Read more.
Chlamydia trachomatis infection is a public health problem. Serological tests can determine the disease burden and serve as a biomarker for identifying patients with infertility due to tubal obstruction. However, cross-reactions between chlamydial species have been reported, which causes problems with diagnosis. A real-time PCR commercial test for the detection of endocervical infection and two ELISAs with the recombinant major outer membrane protein (rMOMP) from C. trachomatis and C. abortus as antigens were used to diagnose both infections. The prevalence of endocervical infection by C. trachomatis was 7.77%, and that of IgG antibodies against C. trachomatis and C. abortus was 31.1% and 10.7%, respectively. The ELISA with C. trachomatis rMOMP showed a sensitivity of 75% and a specificity of 72.5%. The lowest sensitivity (25%) and high specificity (76.8%) were obtained with anti-C. abortus rMOMP ELISAs. A low cross-reactivity of 7% between ELISA tests was observed. Conclusion. The recombinant MOMP ELISA could help identify women who had contact with C. trachomatis or C. abortus and could be a tool to lower the costs of performing molecular testing on all patients attending an infertility clinic. Full article
(This article belongs to the Special Issue Host–Microbe Interactions in Health and Disease)
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14 pages, 1903 KB  
Article
Metagenomic Analyses of Gut Bacteria of Two Sandfly Species from Western Ghats, India, Differing in Their Vector Competence for Leishmaniasis
by Anns Tom, Nanda Kumar Yellapu, Manju Rahi and Prasanta Saini
Microorganisms 2025, 13(7), 1615; https://doi.org/10.3390/microorganisms13071615 - 9 Jul 2025
Viewed by 437
Abstract
Phlebotomine sandflies are the primary vectors of Leishmania parasites, the causative agents of leishmaniasis. In India, Phlebotomus argentipes is the confirmed vector of Leishmania donovani. The sandfly gut microbiota plays a crucial role in Leishmania development and transmission, yet it remains largely [...] Read more.
Phlebotomine sandflies are the primary vectors of Leishmania parasites, the causative agents of leishmaniasis. In India, Phlebotomus argentipes is the confirmed vector of Leishmania donovani. The sandfly gut microbiota plays a crucial role in Leishmania development and transmission, yet it remains largely understudied. This study used a metagenomic approach targeting the V3–V4 region of the 16S rRNA gene to compare the gut bacterial communities of P. argentipes and Sergentomyia babu prevalent in Kerala. A total of 18 distinct bacterial phyla were identified in P. argentipes, and 14 in S. babu, both dominated by Proteobacteria, Actinobacteria, and Firmicutes. A total of 315 genera were identified in P. argentipes, with a high relative abundance of Pseudomonas (6.3%), whereas S. babu harbored 327 genera, with Pseudomonas showing a higher relative abundance of 11%. Unique to P. argentipes, bacterial phyla such as Fusobacteria, Armatimonadetes, Elusimicrobia, Chlamydiae, and Crenarchaeota were identified, whereas Chlorobi was specific to S. babu. Additionally, 145 species were identified in P. argentipes, compared to 164 species in S. babu. These findings provide a comparative baseline of gut microbial diversity between vector and non-vector sandfly species, offering a foundation for future functional investigations into vector competence. Full article
(This article belongs to the Topic Diversity of Insect-Associated Microorganisms)
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Article
Proinflammatory Cytokines in Women with PCOS in Atypical Pathogen Infections
by Izabela Chudzicka-Strugała, Iwona Gołębiewska, Grzegorz Brudecki, Wael Elamin, Beata Banaszewska, Marta Chudzicka-Adamczak, Dominik Strugała and Barbara Zwoździak
Diagnostics 2025, 15(13), 1669; https://doi.org/10.3390/diagnostics15131669 - 30 Jun 2025
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Abstract
Background/Objectives: Polycystic ovary syndrome (PCOS) is one of the most frequently diagnosed endocrine and metabolic disorders in women of reproductive age before menopause. It is associated with excess androgens and ovarian dysfunction, reduced fertility, the presence of obstetric disorders, but also metabolic disorders, [...] Read more.
Background/Objectives: Polycystic ovary syndrome (PCOS) is one of the most frequently diagnosed endocrine and metabolic disorders in women of reproductive age before menopause. It is associated with excess androgens and ovarian dysfunction, reduced fertility, the presence of obstetric disorders, but also metabolic disorders, and, among others, insulin resistance, obesity and type II diabetes. Its close relationship with changes in the diversity of the vaginal microbiome, vaginal inflammation and changes in the vaginal microenvironment, which can pave the way for pathogenic microorganisms, is emphasized. Methods: The research in the presented paper focuses on a group of women with PCOS (n = 490) of reproductive age (26–43 years), in whom the frequency of infections of the reproductive system caused by atypical pathogens, Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma spp., were analyzed, and then the immune system response was assessed in terms of the level of serum proinflammatory cytokines, IL-1β, IL-6 and TNF-α. Results: Our results showed a 40% infection rate in the studied group of patients with PCOS, with C. trachomatis being the most common pathogen (17.7%), followed by Ureaplasma spp. (10%) and M. hominis (4.9%). In some cases, co-infections such as Mycoplasma and Ureaplasma were also observed in 3.1% or all three atypical bacteria, M. hominis, Ureaplasma spp. and C. trachomatis, in 4.3% of patients with PCOS. In our study, in women with PCOS and confirmed infection with any atypical pathogen (n = 196), we analyzed the levels of proinflammatory cytokines, IL-1 β a, IL-6 and TNF-α. The results were compared with a control group (control group A) consisting of patients with the same underlying disease, i.e., PCOS (n = 39), who did not experience infection with atypical pathogens or symptoms of gynecological infection. Additionally, a control group B (n = 28) consisting of healthy women (without PCOS and without infection) was introduced. The results regarding the levels of cytokines studied in this work (IL-1β, IL-6, TNF-α) may suggest that the presence of intracellular C. trachomatis in the infection will play a dominant role in the immune system response. In the infections with atypical pathogens analyzed in this study in patients with PCOS, no characteristic clinical features were observed, apart from indications in the form of an increase in the number of leukocytes in the assessment of the vaginal biocenosis, suggesting cervicitis and reported reproductive failure or lower abdominal pain. An additional problem is the inability to detect the presence of atypical pathogens in routine microbiological tests; therefore, confirmation of such etiology requires referral of the patient for targeted tests. Conclusions: Invasion of host cells by atypical pathogens such as C. trachomatis and infections with “genital mycoplasmas” can disrupt the function of these cells and lead to many complications, including infertility. The immune response with the production of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6, observed in response to infection with C. trachomatis, M. hominis, and Ureaplasma spp., induces or amplifies inflammation by activating immune cells or controlling infection, but may lead to the facilitation of the survival of pathogenic microorganisms and irreversible damage to fallopian tube tissues. Especially in the case of the proinflammatory cytosine TNF-α, there seems to be a close correlation with infections with atypical pathogens and a marked immune response, as well as with increased IL-1β and IL-6 values compared with the absence of infection (both in the presence and absence of PCOS). The presented study may suggest the importance of extended diagnostics to include atypical pathogens in the case of PCOS and the importance of research in this area also from the point of view of the immune response. Full article
(This article belongs to the Special Issue Diagnosis and Management of Gynecological Diseases in 2025)
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