4CMenB journey to the 10-year anniversary and beyond.

The 4-component meningococcal serogroup B (MenB) vaccine, 4CMenB, the first broadly protective, protein-based MenB vaccine to be licensed, is now registered in more than 50 countries worldwide. Real-world evidence (RWE) from the last decade confirms its effectiveness and impact, with infant immunization programs showing vaccine effectiveness of 71-95% against invasive MenB disease and cross-protection against non-B serogroups, including a 69% decrease in serogroup W cases in 4CMenB-eligible cohorts in England. RWE from different countries also demonstrates the potential for additional moderate protection against gonorrhea in adolescents. The real-world safety profile of 4CMenB is consistent with prelicensure reports. Use of the endogenous complement human serum bactericidal antibody (enc-hSBA) assay against 110 MenB strains may enable assessment of the immunological effectiveness of multicomponent MenB vaccines in clinical trial settings. Equitable access to 4CMenB vaccination is required to better protect all age groups, including older adults, and vulnerable groups through comprehensive immunization policies.

Invasive meningococcal disease, caused by the bacterium Neisseria meningitidis(meningococcus), is rare but often devastating and can be deadly. Effective vaccines are available, including vaccines against meningococcal serogroup B disease. In 2013, the 4-component meningococcal serogroup B vaccine, 4CMenB, became the first broadly protective, protein-based vaccine against serogroup B to be licensed, with the second (bivalent vaccine, MenB-FHbp) licensed the following year. 4CMenB is now registered in more than 50 countries, in the majority, for infants and all age groups. In the US, it is approved for individuals aged 10­25 years. Evidence from immunization programs in the last decade, comparing vaccinated and unvaccinated individuals and the same population before and after vaccination, confirms the effectiveness and positive impact of 4CMenB against serogroup B disease. This also demonstrates that 4CMenB can provide protection against invasive diseases caused by other meningococcal serogroups. Furthermore, N. meningitidis is closely related to the bacterium that causes gonorrhea, N. gonorrhoeae, and emerging real-world evidence suggests that 4CMenB provides additional moderate protection against gonococcal disease. The safety of 4CMenB when given to large numbers of infants, children, adolescents, and adults is consistent with the 4CMenB safety profile reported before licensure.For the future, it would be beneficial to address differences among national guidelines for the recommended administration of 4CMenB, particularly where there is supportive epidemiological evidence but no equitable access to vaccination. New assays for assessing the potential effectiveness of meningococcal serogroup B vaccines in clinical trials are also required because serogroup B strains circulating in the population are extremely diverse across different countries.

Quality, acceptability and usability of self-sampling kits used by non-healthcare professionals for STI diagnosis in Spain: a single-blind study.

OBJECTIVES: Sexually transmitted infections (STIs) have markedly increased over the last decade in Spain, calling for prevention and control innovative approaches. While there is evidence indicating the effectiveness of self-sampling for STI diagnosis, no kits for this purpose have been authorised in Spain. METHODS: A prospective single-blind cross-sectional study carried out between November and December 2022 in an STI clinic in Madrid, Spain, to determine the validity, feasibility and acceptability of self-sampling kits used by non-healthcare professionals from vagina, pharynx, rectum and urethra to diagnose Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). Self-samples were compared with samples collected by healthcare professional (HC samples) and analysed by PCR. Frequency of CT and NG diagnosis by sample type was compared using McNemar's test for paired data. Sensitivity and specificity of self-samples for CT and NG diagnosis were also calculated. RESULTS: 306 self-samples from 51 participants were analysed. 80% were men with median age of 33 (IQR: 28-38) years. Self-samples and HC samples showed no significant statistical differences in CT and NG diagnosis. Self-samples had a sensitivity of 81% for CT and 93% for NG, with a specificity of 97% for CT and 95% for NG. More than 90% of participants had no difficulty understanding the kit instructions and 71% expressed high levels of satisfaction with the self-sampling kit. CONCLUSION: Self-sampling kits for CT and NG diagnosis can be safely and effectively used by non-healthcare professionals in Spain. National strategies for STI prevention and control should prioritise self-sampling strategies.

A novel murine model mimicking male genital Neisseria species infection using Neisseria musculi†.

With ~78 million cases yearly, the sexually transmitted bacterium Neisseria gonorrhoeae is an urgent threat to global public health due to continued emergence of antimicrobial resistance. In the male reproductive tract, untreated infections may cause permanent damage, poor sperm quality, and subsequently subfertility. Currently, few animal models exist for N. gonorrhoeae infection, which has strict human tropism, and available models have limited translatability to human disease. The absence of appropriate models inhibits the development of vital new diagnostics and treatments. However, the discovery of Neisseria musculi, a mouse oral cavity bacterium, offers much promise. This bacterium has already been used to develop an oral Neisseria infection model, but the feasibility of establishing urogenital gonococcal models is unexplored. We inoculated mice via the intrapenile route with N. musculi. We assessed bacterial burden throughout the male reproductive tract, the systemic and tissue-specific immune response 2-weeks postinfection, and the effect of infection on sperm health. Neisseria musculi was found in penis (2/5) and vas deferens (3/5) tissues. Infection altered immune cell counts: CD19+ (spleen, lymph node, penis), F4/80+ (spleen, lymph node, epididymus), and Gr1+ (penis) compared with noninfected mice. This culminated in sperm from infected mice having poor viability, motility, and morphology. We hypothesize that in the absence of testis infection, infection and inflammation in other reproductive is sufficient to damage sperm quality. Many results herein are consistent with outcomes of gonorrhoea infection, indicating the potential of this model as a tool for enhancing the understanding of Neisseria infections of the human male reproductive tract.

Establishment of droplet digital PCR for the detection of Neisseria gonorrhoeae.

BACKGROUND: Infection with Neisseria gonorrhoeae in adults usually leads to vaginitis and acute urethritis, and infection through the birth canal in newborns can lead to acute neonatal conjunctivitis. In view of certain factors such as a high missed detection rate of N.gonorrhoeae from staining microscopy method, the time-consuming nature and limited sensitivity of bacterial culture method, complicated and inability of absolute quantification from the ordinary PCR method. METHODS: This study aims to establish a ddPCR system to detect N.gonorrhoeae in a absolute quantification, high specificity, high stability and accurate way. We selected the pgi1 gene as the target gene for the detection of N.gonorrhoeae. RESULTS: The amplification efficiency was good in the ddPCR reaction, and the whole detection process could be completed in 94 min. It has a high sensitivity of up to 5.8 pg/µL. With a high specificity, no positive microdroplets were detected in 9 negative control pathogens in this experiment. In addition, ddPCR detection of N.gonorrhoeae has good repeatability, and the calculated CV is 4.2 %. CONCLUSIONS: DdPCR detection technology has the characteristics of absolute quantification, high stability, high specificity and high accuracy of N.gonorrhoeae. It can promote the accuracy of the detecting of N.gonorrhoeae, providing a more scientific basis for clinical diagnosis and treatment.

Economic evaluation alongside a clinical trial of near-to-patient testing for sexually transmitted infections.

BACKGROUND: Current clinical care for common bacterial STIs (Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Mycoplasma genitalium (MG)) involves empiric antimicrobial therapy when clients are symptomatic, or if asymptomatic, waiting for laboratory testing and recall if indicated. Near-to-patient testing (NPT) can improve pathogen-specific prescribing and reduce unnecessary or inappropriate antibiotic use in treating sexually transmitted infections (STI) by providing same-day delivery of results and treatment. METHODS: We compared the economic cost of NPT to current clinic practice for managing clients with suspected proctitis, non-gonococcal urethritis (NGU), or as an STI contact, from a health provider's perspective. With a microsimulation of 1000 clients, we calculated the cost per client tested and per STI- and pathogen- detected for each testing strategy. Sensitivity analyses were conducted to assess the robustness of the main outcomes. Costs are reported as Australian dollars (2023). RESULTS: In the standard care arm, cost per client tested for proctitis, NGU in men who have sex with men (MSM) and heterosexual men were the highest at $247.96 (95% Prediction Interval (PI): 246.77-249.15), $204.23 (95% PI: 202.70-205.75) and $195.01 (95% PI: 193.81-196.21) respectively. Comparatively, in the NPT arm, it costs $162.36 (95% PI: 161.43-163.28), $158.39 (95% PI: 157.62-159.15) and $149.17 (95% PI: 148.62-149.73), respectively. Using NPT resulted in cost savings of 34.52%, 22.45% and 23.51%, respectively. Among all the testing strategies, substantial difference in cost per client tested between the standard care arm and the NPT arm was observed for contacts of CT or NG, varying from 27.37% to 35.28%. CONCLUSION: We found that NPT is cost-saving compared with standard clinical care for individuals with STI symptoms and sexual contacts of CT, NG, and MG.

Mini-Multilocus Sequence Typing Scheme for the Global Population of Neisseria gonorrhoeae.

The increasing problem of antimicrobial resistance in N. gonorrhoeae necessitates the development of molecular typing schemes that are suitable for rapid and mass screening. The objective of this study was to design and validate a mini-MLST scheme for N. gonorrhoeae based on global pathogen population data. Using sequences of seven housekeeping genes of 21,402 isolates with known MLSTs from the PubMLST database, we identified eighteen informative polymorphisms and obtained mini-MLST nucleotide profiles to predict MLSTs of isolates. We proposed a new MLST grouping system for N. gonorrhoeae based on mini-MLST profiles. Phylogenetic analysis revealed that MLST genogroups are a stable characteristic of the N. gonorrhoeae global population. The proposed grouping system has been shown to bring together isolates with similar antimicrobial susceptibility, as demonstrated by the characteristics of major genogroups. Established MLST prediction algorithms based on nucleotide profiles are now publicly available. The mini-MLST scheme was evaluated using a MLST detection/prediction method based on the original hydrogel DNA microarray. The results confirmed a high predictive ability up to the MLST genogroup. The proposed holistic approach to gonococcal population analysis can be used for the continuous surveillance of known and emerging resistant N. gonorrhoeae isolates.

Prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis, Ureaplasma urealyticum among outpatients in central China: A retrospective study.

Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU) are the common sexually transmitted pathogens and lead to genital diseases, highly prevalent all around the world. The objective of this study was to analyze the prevalence of NG, CT and UU among outpatients in central China. A total of 2186 urogenital swabs were collected from the patients and the NG, CT and UU pathogens were testing with RT-PCR method, meanwhile the medical records were obtained from the hospital information system. The overall infection rates of NG, CT and UU were 4.57 %, 6.63 % and 48.81 % respectively, showed the prevalence of UU was higher than NG and CT. The younger people had the highest infection rate of NG (10.81 %), CT (20.54 %) and UU (54.59 %). Single infection (89.09 %) was significant higher than co-infection (10.91 %), and the CT-UU co-infection was the prominent pattern (66.41 %). There were an obvious sex difference, the prevalence of NG and CT were significant higher in male, whereas UU was higher in female. Our study could contributed a better understanding of the prevalence of NG, CT and UU, facilitating to the development of effective screening, prevention and treatment policies.

Optimal Protein Allocation Controls the Inhibition of GltA and AcnB in Neisseria gonorrhoeae.

Neisseria gonorrhea (Ngo) is a major concern for global public health due to its severe implications for reproductive health. Understanding its metabolic phenotype is crucial for comprehending its pathogenicity. Despite Ngo's ability to encode TCA cycle proteins, GltA and AcnB, their activities are notably restricted. To investigate this phenomenon, we used the iNgo_557 metabolic model and incorporated a constraint on total cellular protein content. Our results indicate that low cellular protein content severely limits GltA and AcnB activity, leading to a shift towards acetate overflow for ATP production, which is more efficient in terms of protein usage. Surprisingly, increasing cellular protein content alleviates this restriction on GltA and AcnB and delays the onset of acetate overflow, highlighting protein allocation as a critical determinant in understanding Ngo's metabolic phenotype. These findings underscore the significance of Ngo's metabolic adaptation in light of optimal protein allocation, providing a blueprint to understand Ngo's metabolic landscape.

Oxydifficidin, a potent Neisseria gonorrhoeae antibiotic due to DedA assisted uptake and ribosomal protein RplL sensitivity.

Gonorrhea, which is caused by Neisseria gonorrhoeae, is the second most prevalent sexually transmitted infection worldwide. The increasing appearance of isolates that are resistant to approved therapeutics raises the concern that gonorrhea may become untreatable. Here, we serendipitously identified oxydifficidin as a potent N. gonorrhoeae antibiotic through the observation of a Bacillus amyloliquefaciens contaminant in a lawn of N. gonorrhoeae. Oxydifficidin is active against both wild-type and multidrug-resistant N. gonorrhoeae. It's potent activity results from a combination of DedA-assisted uptake into the cytoplasm and the presence of an oxydifficidin-sensitive ribosomal protein L7/L12 (RplL). Our data indicates that oxydifficidin binds to the ribosome at a site that is distinct from other antibiotics and that L7/L12 is uniquely associated with its mode of action. This study opens a potential new avenue for addressing antibiotic resistant gonorrhea and underscores the possibility of identifying overlooked natural products from cultured bacteria, particularly those with activity against previously understudied pathogens.

Management of Neisseria gonorrhoeae infection: from drug resistance to drug repurposing.

INTRODUCTION: Neisseria gonorrhoeae is a common sexually transmitted disease connected with extensive drug resistance to many antibiotics. Presently, only expanded spectrum cephalosporins (ceftriaxone and cefixime) and azithromycin remain useful for its management. AREAS COVERED: New chemotypes for the classical antibiotic drug target gyrase/topoisomerase IV afforded inhibitors with potent binding to these enzymes, with an inhibition mechanism distinct from that of fluoroquinolones, and thus less prone to mutations. The α-carbonic anhydrase from the genome of this bacterium (NgCAα) was also validated as an antibacterial target. EXPERT OPINION: By exploiting different subunits from the gyrase/topoisomerase IV as well as new chemotypes, two new antibiotics reached Phase II/III clinical trials, zoliflodacin and gepotidacin. They possess a novel inhibition mechanism, binding in distinct parts of the enzyme compared to the fluoroquinolones. Other chemotypes with inhibitory activity in these enzymes were also reported. NgCAα inhibitors belonging to a variety of classes were obtained, with several sulfonamides showing MIC values in the range of 0.25-4 µg/mL and significant activity in animal models of this infection. Acetazolamide and similar CA inhibitors might thus be repurposed as antiinfectives. The scientific/patent literature has been searched for on PubMed, ScienceDirect, Espacenet, and PatentGuru, from 2016 to 2024.

Prevalence and associated risk factors of chlamydia and gonorrhoea infections among men who have sex with men in Durban, South Africa.

Despite significant research on the prevalence of STIs in South African men who have sex with men (MSM), recent data on the prevalence and risk factors for curable STI infections among this key populations are limited. This study determined the prevalence of and risk factors associated with Neisseria gonorrhoeae and Chlamydia trachomatis infections among MSM. The sample consisted of 200 MSM resident in Durban. Data were collected using a self-administered questionnaire, and urine samples were collected and tested for N. gonorrhoeae and C. trachomatis. The prevalence of N. gonorrhoeae and C. trachomatis were 3.0% and 6.0%, respectively. Younger age was significantly associated with testing positive for C. trachomatis (p=0.037). Being between the ages of 30-39 years old reduced the risk of acquiring C. trachomatis infection (OR: 0.10, 95% CI: 0.0120-0.7564, p=0.026). In addition, being circumcised reduced the risk of contracting C. trachomatis (adjusted OR: 0.01, 95% CI: 0.0005-0.3516, p=0.01). However, having between 2-4 sex partners increased the risk of testing positive for C. trachomatis (adjusted OR: 107.45, 95% CI: 1.3467-8573.3130, p=0.036). The following factors were significantly associated (p<0.05) with testing positive for N. gonorrhoeae infection: cohabiting with sex partner, engaging in group sex, and drug use. Fear and stigma were the main barriers to accessing health care in the studied population. This study provided evidence of high rates of C. trachomatis infection among MSM resident in Durban. Based on the results, South African MSM, especially the young MSM population, should be given priority when delivering intervention programs to prevent STIs.

Malgré des recherches importantes sur la prévalence des IST chez les hommes sud-africains ayant des rapports sexuels avec des hommes (HSH), les données récentes sur la prévalence et les facteurs de risque d'infections IST curables parmi ces populations clés sont limitées. Cette étude a déterminé la prévalence et les facteurs de risque associés aux infections à Neisseria gonorrhoeae et à Chlamydia trachomatis chez les HARSAH. L'échantillon était composé de 200 HSH résidant à Durban. Les données ont été collectées à l'aide d'un questionnaire auto-administré et des échantillons d'urine ont été collectés et testés pour N. gonorrhoeae et C. trachomatis. La prévalence de N. gonorrhoeae et de C. trachomatis était respectivement de 3,0 % et 6,0 %. Un âge plus jeune était significativement associé à un test positif pour C. trachomatis (p = 0,037). Le fait d'être âgé de 30 à 39 ans réduisait le risque de contracter une infection à C. trachomatis (OR : 0,10, IC à 95 % : 0,0120-0,7564, p = 0,026). De plus, être circoncis réduisait le risque de contracter C. trachomatis (OR ajusté : 0,01, IC à 95 % : 0,0005-0,3516, p=0,01). Cependant, avoir entre 2 et 4 partenaires sexuels augmentait le risque d'être testé positif pour C. trachomatis (OR ajusté : 107,45, IC à 95 % : 1,3467-8573,3130, p=0,036). Les facteurs suivants étaient significativement associés (p < 0,05) au test positif pour l'infection à N. gonorrhoeae : cohabitation avec un partenaire sexuel, participation à des relations sexuelles en groupe et consommation de drogues. La peur et la stigmatisation étaient les principaux obstacles à l'accès aux soins de santé dans la population étudiée. Cette étude a mis en évidence des taux élevés d'infection à C. trachomatis parmi les HSH résidant à Durban. Sur la base des résultats, les HSH sud-africains, en particulier la jeune population HSH, devraient être prioritaires lors de la mise en œuvre de programmes d'intervention visant à prévenir les IST.

World Health Organization Enhanced Gonococcal Antimicrobial Surveillance Programme, Cambodia, 2023.

To determine antimicrobial susceptibility of Neisseria gonorrhoeae, we analyzed phenotypes and genomes of 72 isolates collected in Cambodia in 2023. Of those, 9/72 (12.5%) were extensively drug resistant, a 3-fold increase from 2022. Genomic analysis confirmed expansion of newly emerging resistant clones and ongoing resistance emergence across new phylogenetic backbones.

Molecular detection of ceftriaxone resistance in Neisseria gonorrhoeae clinical specimens: a tool for public health control.

OBJECTIVES: This study aimed to validate and implement a rapid screening assay for molecular detection of the penA-60 allele that is associated with ceftriaxone resistance in Neisseria gonorrhoeae for use on both isolate lysates and clinical specimen DNA extracts. METHODS: A N. gonorrhoeae penA real-time (RT)-PCR was adapted to include a species-specific pap confirmation target and a commercially available internal control to monitor for PCR inhibition.The modified assay was validated using N. gonorrhoeae-positive (n=24) and N. gonorrhoeae-negative (n=42) clinical specimens and isolate lysates. The panel included seven samples with resistance conferred by penA alleles targeted by the assay and four samples with different penA alleles. The feasibility of using the penA RT-PCR for molecular surveillance was assessed using clinical specimens from 54 individuals attending a London sexual health clinic who also had a N. gonorrhoeae isolate included in the 2020 Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP). RESULTS: The assay correctly identified N. gonorrhoeae specimens (n=7) with penA-60/64 alleles targeted by the assay. No penA false negatives/positives were detected, giving the penA target of the assay a sensitivity, specificity, positive and negative predicted values (PPV, NPV) of 100% (95% CIs; sensitivity; 56.1-100%, specificity; 93.6-100%, PPV; 56.1-100%, NPV; 93.6-100%).No cross-reactivity with other Neisseria species or other urogenital pathogens was detected. The N. gonorrhoeae target (pap) was detected in 73 out of 78 of the N. gonorrhoeae-positive specimens, resulting in 92.6% sensitivity (95% CI 83.0% to 97.3%), 100% specificity (95% CI 75.9% to 100%) and PPV, and a NPV of 89.4% (95% CI 52.5% to 90.9%). No penA-59/60/64 alleles were detected within the clinical specimens from the GRASP 2020 feasibility molecular surveillance study (n=54 individuals). CONCLUSION: The implementation of this PCR assay for patient management, public health and surveillance purposes enables the rapid detection of gonococcal ceftriaxone resistance conferred by the most widely circulating penA alleles.

HIV-Negative MSM Infected with Two Different Isolates of Drug-Resistant Neisseria gonorrhoeae-Case Report.

The antimicrobial resistance of Neisseria gonorrhoeae (NG) is an increasing public health concern, highlighted by the fact that gonococcus is considered as a 'high'-priority pathogen by the WHO for research and development of new therapeutic options. According to the data of the European Centre for Disease Prevention and Control (ECDC) in 2022, the rate of NG infections is the highest recorded since European surveillance of sexually transmitted infections began in 2009. We report a brief description of a patient infected with two different isolates of drug-resistant N. gonorrhoeae. N. gonorrhoeae cultures were positive from oropharyngeal and urethral swabs and isolates had different antimicrobial susceptibility. We investigated the antimicrobial susceptibility of these isolates to six antimicrobials (ceftriaxone, cefixime, azithromycin, ciprofloxacin, tetracycline, and benzylpenicillin), and minimum inhibitory concentrations (MICs; mg/L) were determined using Etest on gonococcal isolates. Oropharyngeal isolate was resistant to azithromycin while urethral was resistant to penicillin, ciprofloxacin, and tetracycline. Two different and phylogenetically distinct sequence types of NG isolates were identified. Understanding the dynamics and drivers of resistance spread can provide an improved rationale for antibiotic management, and the level of NG resistance should be monitored closely.

Investigating the importance of selected surface-exposed loops in HpuB for hemoglobin binding and utilization by Neisseria gonorrhoeae.

Neisseria gonorrhoeae is the etiological agent of the sexually transmitted infection gonorrhea. The pathogen is a global health challenge since no protective immunity results from infection, and far fewer treatment options are available with increasing antimicrobial resistance. With no efficacious vaccines, researchers are exploring new targets for vaccine development and innovative therapeutics. The outer membrane TonB-dependent transporters (TdTs) produced by N. gonorrhoeae are considered promising vaccine antigens as they are highly conserved and play crucial roles in overcoming nutritional immunity. One of these TdTs is part of the hemoglobin transport system comprised of HpuA and HpuB. This system allows N. gonorrhoeae to acquire iron from hemoglobin (hHb). In the current study, mutations in the hpuB gene were generated to better understand the structure-function relationships in HpuB. This study is one of the first to demonstrate that N. gonorrhoeae can bind to and utilize hemoglobin produced by animals other than humans. This study also determined that when HpuA is absent, mutations targeting extracellular loop 7 of HpuB led to defective hHb binding and utilization. However, when the lipoprotein HpuA is present, these loop 7 mutants recovered their ability to bind hHb, although the growth phenotype remained significantly impaired. Interestingly, loop 7 contains putative heme-binding motifs and a hypothetical α-helical region, both of which may be important for the use of hHb. Taken together, these results highlight the importance of loop 7 in the functionality of HpuB in binding hHb and extracting and internalizing iron.

Mycoplasma genitalium prevalence, co-infection and macrolide resistance-associated mutations in Southern Vietnam.

Mycoplasma genitalium is an emerging sexually transmitted infection, with increasing rates of macrolide resistance and some ways of treatments being recommended by many countries. This study aimed to investigate the prevalence of M. genitalium infection, M. genitalium co-infection with other sexually transmitted organisms, and the frequency of macrolide antibiotic resistance genotypes identified in urethral specimens collected from male and urethral, vaginal and cervical specimens from female who visited the STIs clinic of HCMC Hospital of Dermato-Venereology, Vietnam. The results obtained positive samples for C. trachomatis was 8.46%, N. gonorrhoeae was 6.28%, and M. genitalium was 5.95%. Fifty-five out of 90 M. genitalium samples were found to have mutations in the 23S rRNA gene associated with macrolide resistance (61.11%). M. genitalium/C. trachomatis co-infection was 6.19%, and M. genitalium/N. gonorrhoeae was 1.22%. The percentage of M. genitalium carrying the macrolide resistance mutant gene co-infected with C. trachomatis accounted for 37.50%. The high prevalence of the M. genitalium mutations associated with macrolide resistance showed the importance of M. genitalium testing.

Honokiol Exhibits Anti-NLRP3 Inflammasome and Antimicrobial Properties in Neisseria gonorrhoeae-Infected Macrophages.

Purpose: The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, crucial in infectious and inflammatory diseases by regulating IL-1ß, presents a target for disease management. Neisseria gonorrhoeae causes gonorrhea in over 87 million people annually, with previous research revealing NLRP3 inflammasome activation in infected macrophages. No natural products have been reported to counteract this activation. Exploring honokiol, a phenolic compound from Chinese herbal medicine, we investigated its impact on NLRP3 inflammasome activation in N. gonorrhoeae-infected macrophages. Methods: Honokiol's impact on the protein expression of pro-inflammatory mediators was analyzed using ELISA and Western blotting. The generation of intracellular H2O2 and mitochondrial reactive oxygen species (ROS) was detected through specific fluorescent probes (CM-H2DCFDA and MitoSOX, respectively) and analyzed by flow cytometry. Mitochondrial membrane integrity was assessed using specific fluorescent probes (MitoTracker and DiOC2(3)) and analyzed by flow cytometry. Additionally, the effect of honokiol on the viability of N. gonorrhoeae was examined through an in vitro colony-forming units assay. Results: Honokiol effectively inhibits caspase-1, caspase-11 and GSDMD activation and reduces the extracellular release of IL-1ß, NLRP3, and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) in N. gonorrhoeae-infected macrophages. Detailed investigations have demonstrated that honokiol lowers the production of H2O2 and the phosphorylation of ERK1/2 in N. gonorrhoeae-infected macrophages. Importantly, the phosphorylation of JNK1/2 and p38 and the activation of NF-κB remain unaffected. Moreover, honokiol reduces the N. gonorrhoeae-mediated generation of reactive oxygen species within the mitochondria, preserving their integrity. Additionally, honokiol suppresses the expression of the pro-inflammatory mediator IL-6 and inducible nitric oxide synthase induced by N. gonorrhoeae independently of NLRP3. Impressively, honokiol exhibits in vitro anti-gonococcal activity against N. gonorrhoeae. Conclusion: Honokiol inhibits the NLRP3 inflammasome in N. gonorrhoeae-infected macrophages and holds great promise for further development as an active ingredient in the prevention and treatment of symptoms associated with gonorrhea.

Prevalence of cefixime-resistant Neisseria gonorrhoeae in Melbourne, Australia, 2021-2022.

While ceftriaxone remains the first-line treatment for gonorrhoea, the US CDC recommended cefixime as a second-line treatment in 2021. We tested 1176 Neisseria gonorrhoeae isolates among clients attending the Melbourne Sexual Health Centre in 2021-2022. The prevalence of cefixime resistance was 6.3% (74/1176), azithromycin resistance was 4.9% (58/1176) and ceftriaxone resistance was 0% (0/1176). Cefixime resistance was the highest among women (16.4%, 10/61), followed by men-who-have-sex-with-women (6.4%, 7/109), and men-who-have-sex-with-men (5.8%, 57/982). The prevalence of cefixime-resistant N. gonorrhoeae exceeds the threshold of the 5% resistance level recommended by the World Health Organization; and thus, cefixime treatment would have limited benefits in Australia.

Antimicrobial Susceptibility and Characteristics of Neisseria gonorrhoeae Isolates from Puerto Rico, 2012-2017.

OBJECTIVE: Monitoring the susceptibility patterns of Neisseria gonorrhoeae is essential for the continuing compliance with current treatment recommendations. Puerto Rico conducts susceptibility tests on N. gonorrhoeae; however, trends on antimicrobial resistance in the island have not been reported since the mid 80's. METHODS: We performed a secondary analysis of a national data repository on the antimicrobial susceptibility of N. gonorrhoeae isolates between 2012 and 2017; a period of time when the CDC recommended a single dose of ceftriaxone and azithromycin for the treatment of uncomplicated gonorrhea. Data on susceptibility to eight antibiotics using the standard disk diffusion method was obtained for 30.0% (84/276) of the samples collected from the Sexually Transmitted Disease clinics in Puerto Rico. We also performed patient demographic analyses linked to resistance. RESULTS: Rates of resistance to ceftriaxone and azithromycin were 0% and 4.0% (2/50), respectively. The percentage of isolates resistant to antimicrobials no longer recommended in Puerto Rico, such as tetracycline, ciprofloxacin, and penicillin, was 86.0% (43/50), 76.0% (38/50), and 38.0% (19/50), respectively. Prevalence of resistant N. gonorrhoeae was higher among men who have sex with men, MSM (79%, 37/47). DISCUSSION: Lack of resistance to ceftriaxone and slow emergence of azithromycin resistance was identified from 2012-2017. It is imperative to continue the surveillance for emerging patterns of resistance, especially for ceftriaxone, as it is part of the current treatment guidelines. Therefore, protocols for culture based surveillance, including sample transport and processing, should be strengthened to ensure quality assured epidemiology of gonococcal resistance in Puerto Rico.