Microbiology spectrum最新文献

{"title":"A type-specific B-cell epitope at the apex of outer surface protein C (OspC) of the Lyme disease spirochete, <i>Borreliella burgdorferi</i>.","authors":"David J Vance, Grace Freeman-Gallant, Kathleen McCarthy, Carol Lyn Piazza, Yang Chen, Clint Vorauer, Beatrice Muriuki, Michael J Rudolph, Lisa Cavacini, Miklos Guttman, Nicholas J Mantis","doi":"10.1128/spectrum.02883-24","DOIUrl":"10.1128/spectrum.02883-24","url":null,"abstract":"<p><p>Broadly protective immunity to the Lyme disease spirochete, <i>Borreliella burgdorferi</i>, is constrained by antibodies against type-specific epitopes on outer surface protein C (OspC), a homodimeric helix-rich lipoprotein essential for early stages of spirochete dissemination in vertebrate hosts. However, the molecular basis for type-specific immunity has not been fully elucidated. In this report, we produced and characterized an OspC mouse monoclonal antibody, 8C1, that recognizes native and recombinant OspC type A (OspC_A) but not OspC type B or K. Epitope mapping by hydrogen-deuterium exchange mass spectrometry (HDX-MS) localized 8C1's epitope to a protruding ridge on the apex of OspC_Aα-helix 3 (residues 130-150) previously known to be an immunodominant region of the molecule. Alanine scanning pinpointed 8C1's core binding motif to a solvent exposed patch consisting of residues K₁₄₁, H₁₄₂, T₁₄₃, and D₁₄₄. Analysis of 26 Lyme disease-positive serum samples confirmed human antibody reactivity with this region of OspC_A, with residues E₁₄₀ and D₁₄₄ as being the most consequential. Our results underscore the importance of α-helix 3 as a target of type-specific epitopes on OspC_A that should be taken into consideration in Lyme disease vaccine design.IMPORTANCEA central challenge in the development of vaccines against Lyme disease, the most common vector-borne infection in the United States, is the antigenically variable nature of the lipoproteins displayed on the surface of the disease-causing spirochete, <i>Borreliella burgdorferi</i>. For example, antibodies against one type of outer surface protein C (OspC), a lipoprotein involved in <i>B. burgdorferi</i> transmission and early stages of infection, may have little or no cross reactivity with another seemingly closely related variant of OspC, thereby hampering the use of a single OspC type as a vaccine antigen. For the sake of vaccine design, it is critical to identify the specific epitopes on OspC that both restrict and enable cross-reactivity.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0288324"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960070/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibiotic use among young, hospitalized children in Jordan, 2010-2023.","authors":"Haya Hayek, Justin Z Amarin, Olla Hamdan, Yasmeen Z Qwaider, Tala Khraise, Ritu Banerjee, Andrew J Spieker, James D Chappell, Najwa Khuri-Bulos, Sophie E Katz, Leigh M Howard, Natasha B Halasa","doi":"10.1128/spectrum.02691-24","DOIUrl":"10.1128/spectrum.02691-24","url":null,"abstract":"<p><p>Inappropriate antibiotic use drives antimicrobial resistance, a global health threat causing increased morbidity and mortality. Understanding antibiotic practices in low-resource settings is essential to identify intervention targets. This study investigates antibiotic prescription practices in Amman, Jordan. We conducted three prospective viral surveillance studies at the largest public hospital in Amman, Jordan (2010-2013, 2020, and 2023) and included children <2 years old hospitalized with fever or respiratory symptoms. The data collected included antibiotic use and the results of blood, urine, and cerebrospinal fluid (CSF) cultures performed. We classified antibiotics according to the 2023 WHO AWaRe system. Nasal or throat samples were tested in a research laboratory for respiratory viruses using RT-PCR. The median age of the 4,724 children included was 3.5 months (IQR, 1.6-8.4). A clinical blood, urine, or CSF sample was collected from 2,565/4,712 children (54.4%), 356 (13.9%) of whom tested positive. During hospitalization, 4,375 children (92.6%) received at least one antibiotic, and 4,245 (97.0%) received at least one antibiotic from the <i>Watch</i> group. One or more respiratory viruses were detected in 3,911 children (82.8%). Providers ordered cultures most often for children 0-2 months old (<i>n</i> = 1,579 [73.5%]) and those with an admission diagnosis of rule-out sepsis (<i>n</i> = 1,164 [95.4%]). Antibiotic use and testing practices were consistent across study years, age groups, and admission diagnoses. In conclusion, widespread antibiotic use despite the preponderance of viral infections highlights a significant discrepancy in aligning treatment practices with disease etiology. Strengthening diagnostic and preventive capabilities in low-resource settings is crucial to combat antimicrobial resistance.</p><p><strong>Importance: </strong>In this study of 4,724 children under 2 years old hospitalized in the largest public hospital in Jordan between 2010 and 2023, 92.6% received antibiotics despite 82.8% testing positive for respiratory viruses and only 13.9% of collected cultures suggesting bacterial infection. Despite the predominance of viral infections, the widespread use of antibiotics, particularly from the World Health Organization Watch group, highlights the need for improved antibiotic stewardship and diagnostic capabilities in Jordan.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0269124"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960133/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum for Yun et al., \"Risk factors for vancomycin treatment failure in heterogeneous vancomycin-intermediate <i>Staphylococcus aureus</i> bacteremia.","authors":"Ji Hyun Yun, Euijin Chang, Seongman Bae, Jiwon Jung, Min Jae Kim, Yong Pil Chong, Sung-Han Kim, Sang-Ho Choi, Sang-Oh Lee, Yang Soo Kim","doi":"10.1128/spectrum.03314-24","DOIUrl":"10.1128/spectrum.03314-24","url":null,"abstract":"","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0331424"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960069/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143483212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The rise in domestic shigellosis and the genomic characteristics of <i>Shigella</i> clones linked to men who have sex with men in Taiwan, 2015‒2022.","authors":"Ying-Shu Liao, Bo-Han Chen, Yu-Ping Hong, You-Wun Wang, Ru-Hsiou Teng, Shiu-Yun Liang, Jui-Hsien Chang, Chi-Sen Tsao, Hsiao Lun Wei, Chien-Shun Chiou","doi":"10.1128/spectrum.02290-24","DOIUrl":"10.1128/spectrum.02290-24","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Since 2015, Taiwan has experienced a notable rise in domestic shigellosis cases, particularly among young adult males. In this study, we aimed to investigate this epidemiological trend through demographic analysis and genomic characterization of bacterial isolates. We analyzed demographic data on shigellosis cases from 2003-2014 to 2015-2022. For cases from 2015-2022, we conducted genomic analyses of &lt;i&gt;Shigella&lt;/i&gt; isolates using pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). Antimicrobial resistance and plasmid profiles were examined to identify genetic determinants of resistance. From 2015 to 2022, there was a noticeable demographic shift in domestic shigellosis cases from females to males and children to young adults. This trend was driven by three multidrug-resistant &lt;i&gt;Shigella&lt;/i&gt; clones associated with men who have sex with men (MSM): ciprofloxacin-resistant &lt;i&gt;S. sonnei&lt;/i&gt; (CipR_SSIII), azithromycin-resistant &lt;i&gt;S. flexneri&lt;/i&gt; 3a (AziR_SF3), and ciprofloxacin-resistant &lt;i&gt;S. flexneri&lt;/i&gt; 2a (CipR_SF2). The CipR_SF2 clone has become the most prevalent since 2018, responsible for 84.9% of cases in 2021. Genomic analysis revealed that CipR_SF2 isolates are genetically distinct from those involved in MSM-related outbreaks in other countries. These MSM-associated clones showed significantly higher resistance to azithromycin, extended-spectrum cephalosporins (ESCs), and ciprofloxacin. Additionally, 14 extensively drug-resistant isolates were identified, carrying resistance genes for azithromycin and ESCs on IncFII or IncB/O/K/Z plasmids. Our findings indicate that the increase in domestic shigellosis cases in Taiwan from 2015 to 2022 is primarily attributed to the spread of highly resistant MSM-associated &lt;i&gt;Shigella&lt;/i&gt; clones.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Importance: &lt;/strong&gt;The rise of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Shigella strains poses a growing global health threat, particularly among high-risk groups such as men who have sex with men (MSM). This study highlights the increasing prevalence of domestic shigellosis in Taiwan from 2015 to 2022, driven by the emergence of three MDR Shigella clones. These MSM-associated clones exhibit significantly higher resistance to azithromycin, extended-spectrum cephalosporins (ESCs), and ciprofloxacin compared to non-MSM-associated clones. Additionally, 14 extensively drug-resistant isolates were identified, carrying resistance genes for azithromycin and ESCs on IncFII or IncB/O/K/Z plasmids. Genomic analysis reveals that ciprofloxacin-resistant Shigella flexneri 2a (CipR_SF2) has become the most dominant clone, responsible for the majority of shigellosis cases since 2018, and is genetically distinct from strains observed in MSM-related outbreaks in other countries. By elucidating these clones' genetic characteristics and epidemiological trends, this research offers essential data for public health surveillance, helping to inform strategies for contr","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0229024"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960102/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143409112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The genetic variation of mitochondrial sequences and pathological differences of <i>Echinococcus multilocularis</i> strains from different continents.","authors":"Baoping Guo, Gang Guo, Wenjing Qi, Malike Aizezi, Chuanchuan Wu, Mengxiao Tian, Adriano Casulli, Wenbao Zhang, Jun Li","doi":"10.1128/spectrum.01318-24","DOIUrl":"10.1128/spectrum.01318-24","url":null,"abstract":"<p><p>Alveolar echinococcosis is a lethal zoonotic disease caused by the fox tapeworm <i>Echinococcus multilocularis</i>. The parasite is widely distributed in the Northern Hemisphere and exhibits low genetic diversity among populations. To compare the differences among four <i>E. multilocularis</i> strains from different geographical locations, namely, Alaska (EM-AK), Japan (EM-JP), Xinjiang (EM-XJ), and Ningxia (EM-NX), their complete mitochondrial (mt) sequences were compared, and their induced pathological lesions were analyzed in mouse models. The complete mt sequence of EM-AK resulted in 0.84%-0.86% variation as compared with the other strains, which had a lower variation. Phylogenetic analysis and parsimony network indicated that EM-AK resulted in 30,000 years of evolutionary distance from the other three strains. EM-AK induced more pathological damage than the other three strains, which was likely to induce more host cell infiltration and acute granuloma in the liver. More importantly, EM-AK produced more protoscoleces than the other three strains, which may impact the transmission dynamics of the parasite. Given the geographical location of four strains, which is far from each other, and also the pathological differences, the strains of <i>E. multilocularis</i> are likely models for addressing the relationship and interfacial immune response between the host and the helminth.IMPORTANCE<i>Echinococcus multilocularis</i> is the causative agent of alveolar echinococcosis, which is considered the most serious parasitic disease in the Northern Hemisphere. There are many genotypes, but the pathogenic and mitochondria sequence and differences are still unclear. Therefore, this study showed both pathological and genetic differences between the four strains of <i>E. multilocularis</i>. EM-AK induced more severe immune responses and especially induced more host cell infiltration, which resulted in more severe granuloma in the liver. EM-JP has metacestode lesions morphologically closer to those of <i>E. granulosus</i> with clear cyst fluid. However, this strain produced much fewer protoscoleces (PSCs). Genetically, EM-AK is more distant from other strains.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0131824"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960119/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wild raccoons (<i>Procyon lotor</i>) as a potential reservoir of cytolethal distending toxin-producing <i>Providencia</i> strains in Japan.","authors":"Okechukwu John Obi, Atsushi Hinenoya, Sharda Prasad Awasthi, Noritoshi Hatanaka, Shah M Faruque, Shinji Yamasaki","doi":"10.1128/spectrum.02616-24","DOIUrl":"10.1128/spectrum.02616-24","url":null,"abstract":"&lt;p&gt;&lt;p&gt;In view of increasing reports of infections due to virulent &lt;i&gt;Providencia&lt;/i&gt; species including cytolethal distending toxin (&lt;i&gt;cdt&lt;/i&gt;) gene-positive strains, it is important to identify the reservoirs and transmission routes of such pathogenic strains. Raccoons considered to be a source of zoonotic pathogens were monitored for the presence of &lt;i&gt;Providencia&lt;/i&gt; species in Japan and analyzed for &lt;i&gt;cdt&lt;/i&gt; genes. Of 384 wild raccoon rectal swabs analyzed, 60% were positive for &lt;i&gt;Providencia&lt;/i&gt; species, of which 20% carried &lt;i&gt;cdt&lt;/i&gt;-genes. Among seven &lt;i&gt;Providencia&lt;/i&gt; species isolated (&lt;i&gt;P. alcalifaciens, P. rustigianii, P. rettgeri, P. stuartii, P. heimbachae, P. vermicola,&lt;/i&gt; and &lt;i&gt;P. huaxiensis&lt;/i&gt;), &lt;i&gt;cdt&lt;/i&gt; genes were distributed in &lt;i&gt;P. alcalifcaiens&lt;/i&gt; (63%), &lt;i&gt;P. rustigianii&lt;/i&gt; (16%), and novel in &lt;i&gt;P. rettgeri&lt;/i&gt; (21%). Complete &lt;i&gt;cdt&lt;/i&gt; gene clusters were identified in &lt;i&gt;P. alcalifaciens&lt;/i&gt; and &lt;i&gt;P. rustigianii&lt;/i&gt; strains, whereas &lt;i&gt;P. rettgeri&lt;/i&gt; had intact &lt;i&gt;cdtB&lt;/i&gt; but truncated &lt;i&gt;cdtA&lt;/i&gt; and &lt;i&gt;cdtC&lt;/i&gt; genes. Phylogenetic analyses showed divergent pulsotypes among the &lt;i&gt;cdt&lt;/i&gt; gene-positive &lt;i&gt;Providencia&lt;/i&gt; strains. Cytotoxicity assay revealed that &lt;i&gt;P. alcalifaciens&lt;/i&gt; and &lt;i&gt;P. rustigianii&lt;/i&gt; produced CDT more toxic to eukaryotic cells compared to human clinical strains, which were neutralized by anti-PaCdtB serum. As expected, the &lt;i&gt;P. rettgeri&lt;/i&gt; strains with truncated &lt;i&gt;cdt&lt;/i&gt; genes had no biological activity. Molecular analysis revealed that all the &lt;i&gt;cdt&lt;/i&gt; genes were located on plasmids as determined by S1-nuclease pulsed-field gel electrophoresis (S1-PFGE) and Southern hybridization assay. Intriguingly, the &lt;i&gt;cdtB&lt;/i&gt; gene in &lt;i&gt;P. rustigianii&lt;/i&gt; strains was detected on dual plasmids. Notably, all the &lt;i&gt;cdt&lt;/i&gt; gene-positive &lt;i&gt;Providencia&lt;/i&gt; strains were found to carry plasmid-mediated T3SS-related genes. These results suggest that wild raccoons are possible reservoir of virulent &lt;i&gt;Providencia&lt;/i&gt; strains in Japan.IMPORTANCE&lt;i&gt;Providencia&lt;/i&gt; species considered normal flora are occasionally associated with gastroenteritis in healthy humans. Cytolethal distending toxin (CDT), a bacterial virulence factor found in various Gram-negative bacteria and associated with gastroenteritis and extra-intestinal infection has also been reported in at least two &lt;i&gt;Providencia&lt;/i&gt; species (&lt;i&gt;P. alcalifaciens&lt;/i&gt; and &lt;i&gt;P. rustigianii&lt;/i&gt;). Determination of the transmission routes of such virulent &lt;i&gt;Providencia&lt;/i&gt; is crucial for the implementation of evidence-based control programs. In this study, we identified raccoons as the probable reservoir of the &lt;i&gt;cdt&lt;/i&gt; gene-positive &lt;i&gt;Providencia&lt;/i&gt; strains in Japan. Interestingly, CDTs produced by raccoon-derived &lt;i&gt;Providencia&lt;/i&gt; strains exerted more toxic effects on the eukaryotic cells compared to the clinical &lt;i&gt;Providencia&lt;/i&gt; strains. In addition, the identification of a novel &lt;i&gt;cdt&lt;/i&gt; gene cluster in another species &lt;i&gt;P. ret","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0261624"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960107/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143492569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A nomogram prediction model for embryo implantation outcomes based on the cervical microbiota of the infertile patients during IVF-FET.","authors":"Yanan Wu, Lingyun Shi, Zili Jin, Wenjun Chen, Fuxin Wang, Huihua Wu, Hong Li, Ce Zhang, Rui Zhu","doi":"10.1128/spectrum.01462-24","DOIUrl":"10.1128/spectrum.01462-24","url":null,"abstract":"<p><p>The microbiota of the female genital tract is crucial for reproductive health. This study aims to investigate the impact of the lower genital tract microbiota on <i>in vitro</i> fertilization and frozen embryo transfer (IVF-FET) outcomes. This study included 131 women aged 20-35 years who underwent their first or second IVF-FET cycle with no obvious unfavorable factors for implantation. Cervical microbiota samples were collected on the embryo transfer day and analyzed using 16S rDNA full-length sequencing. Clinical outcomes were followed up for analysis. Clinical pregnancy (CP) was achieved in 84 patients, and 47 patients experienced non-pregnancy (NP). The cervical microbiota diversity between NP and CP groups showed no significant differences, but some genera such as <i>Halomonas</i> (<i>P</i> = 0.018), <i>Klebsiella</i> (<i>P</i> = 0.039), <i>Atopobium</i> (<i>P</i> = 0.016), and <i>Ligilactobacillus</i> (<i>P</i> = 0.021) were obviously different between the two groups. Notably, there was no significant difference in the abundance of <i>Lactobacillus</i> between the two groups. A nomogram prediction model was developed using the random forest algorithm and logistic regression, including the classification of <i>Halomonas</i>, <i>Atopobium</i>, and <i>Veillonella</i>, as well as the relative abundance of <i>Lactobacillus</i>, to identify high-risk patients with embryo implantation failure. Both internal (area under the curve [AUC] = 0.718, 95% confidence interval [CI]: 0.628-0.807, <i>P</i> < 0.001) and external validation (AUC = 0.654, 95% CI: 0.553-0.755, <i>P</i> = 0.037) of the model performed well. In conclusion, this study established a correlation between cervical microbiota and embryo implantation failure in infertile women undergoing IVF-FET and developed a prediction model that could help in early identification of patients at high risk of implantation failure.IMPORTANCEThis study investigated the potential role of abnormal cervical microbiota in the pathology of implantation failure after <i>in vitro</i> fertilization and frozen embryo transfer (IVF-FET) treatment. Despite nearly half a century of advancements in assisted reproductive technology (ART), the implantation rate of high-quality embryos still hovered around 50%. Moreover, unexplained recurrent implantation failure (RIF) remains a significant challenge in ART. To our knowledge, we first discovered a prediction model for embryo implantation failure, identifying <i>Halomonas</i> and <i>Veillonella</i> as significantly adverse factors for embryo implantation. Despite some limitations, the internal and external validation of the model could bode well for its clinical application prospect. The insights gained from this study pave the way for intervention in the genital tract microbiota prior to IVF-FET, particularly in patients with RIF and RSA.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0146224"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960138/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143573428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of an interferon-gamma release assay for early detection of lumpy skin disease virus infection and vaccination in cattle.","authors":"Nina Kresic, Wannes Philips, Andy Haegeman, Nick de Regge","doi":"10.1128/spectrum.02939-24","DOIUrl":"10.1128/spectrum.02939-24","url":null,"abstract":"<p><p>Lumpy skin disease virus (LSDV) causes a nodular dermatitis in cattle and has high economic consequences in affected areas. Detection of LSDV exposure mostly relies on the humoral immune response, while the cell-mediated immune (CMI) response, an important hallmark of the immune reaction to LSDV, is neglected. We collected samples during 3 weeks post-vaccination of cattle with a Neethling-based live attenuated vaccine (LAV) and during 4 weeks post-LSDV infection under experimental conditions to i) investigate the development of the CMI response, ii) optimize an interferon-gamma release assay (IGRA) by comparing two matrices (whole blood and PBMCs) and different stimuli, and iii) evaluate the usefulness of an IGRA for detection of infection and vaccination. The CMI response to the Neethling LAV was detectable in all animals from 10 days post-vaccination, and importantly, preceded the detection of antibodies. A uniform CMI response to infection was already detected at its plateau level at 7 days post-infection in all animals and also preceded antibody detection. Whole blood and PBMCs allowed efficient IFN-γ secretion, but the IFN-γ response was significantly higher in PBMCs. Heat-inactivated antigen proved to be the stimulus of choice for LSD IGRA, providing increased sensitivity of the test and allowing its performance under BSL2 conditions. Under several conditions, LSDV IGRA showed a specificity of up to 100%. The LSD IGRA could be a powerful immunoassay for early detection of LSD and post-vaccination monitoring, making it worthwhile to explore its diagnostic characteristics in more animals and under field conditions.IMPORTANCEThe immune reaction to lumpy skin disease virus (LSDV) infection or vaccination is currently assessed with serological tests prone to suboptimal sensitivity, long processing time, and the necessity of biosafety level (BSL) 3 laboratories. Furthermore, the delayed or absent seroconversion indicates a need for an alternative immunoassay detecting immune reactions to LSDV exposure applicable in BSL2 settings. Seeing the known importance of cell-mediated immune (CMI) response against poxvirus infections, we evaluated the suitability of the interferon-gamma release assay (IGRA) test for detection of LSDV infection and vaccination. IGRA allowed early detection of the CMI response to LSDV infection (within 7 days) and vaccination (within 10 days) with a Neethling-based live attenuated vaccine, and the CMI response preceded the detection of seroconversion. Whole blood and heat-inactivated antigen increased IGRA sensitivity, making it suitable for application in BSL2 laboratories. This assay overcomes the downsides of currently available immunoassays, and these results encourage its further evaluation.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0293924"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960450/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies.","authors":"Supriya Hunderkar, Nital Ganorkar, Atul Walimbe, Kavita Lole","doi":"10.1128/spectrum.01528-24","DOIUrl":"10.1128/spectrum.01528-24","url":null,"abstract":"<p><p>Hepatitis A virus (HAV) is a major causative agent of self-limiting liver infections. India was highly endemic for HAV in the past; children were exposed to the virus at an early age without any disease symptoms and developed lifelong immunity. With improvements in living conditions, an epidemiological transition is occurring. There is a significant increase in hepatitis A outbreaks involving adolescents and young adults. The gold standard for hepatitis A diagnosis is anti-HAV IgM antibodies. Although antibody responses are primarily targeted against HAV structural proteins (capsid proteins), non-structural proteins are also immunogenic. In the present study, we expressed HAV capsid proteins VP1-2A, VP0 (VP4 + VP2), VP3, and non-structural protein 3C^Pro in the bacterial system and explored the possible use of these as antigens to detect anti-HAV IgM and IgG antibodies using a well-defined serum sample panel. The capsid protein-based assays showed overall less sensitivity for detection of both anti-HAV IgM and IgG antibodies as compared to whole virus antigen-based commercial assays. Among capsid proteins, rVP1-2A showed the highest sensitivity (86.3%) and specificity (84.2%) in detecting anti-HAV IgG, while rVP0 (VP2 + VP4) exhibited the highest sensitivity (79.5%) and specificity (80.2%) for IgM antibodies. Interestingly, r3C^Pro exhibited higher sensitivity (96.9%) and specificity (93.2%) in IgM detection and 93.94% sensitivity and 88% specificity for IgG, indicating its usefulness in detecting both anti-HAV IgM and IgG antibodies during the acute phase of the disease. Though 3C^Pro appeared to be useful in differentiating antibody responses due to infection and vaccination, our analysis revealed that the anti-3C^Pro antibody response is short-lived after natural infection, and hence, it cannot be used as a marker to differentiate between infection and vaccination. However, 3C^Pro would be useful for developing a hepatitis A diagnostic assay.</p><p><strong>Importance: </strong>Hepatitis A was highly endemic in India earlier. With recent developments, there is a shift in the endemicity to intermediate levels. This has resulted in the occurrence of hepatitis outbreaks with symptomatic infections in adolescents and adults. Occasionally, the disease manifestations are serious, leading to acute liver failure. In such a situation, there is a need for a timely diagnosis of the infection.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0152824"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960113/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seroprevalence of SARS-CoV-2 IgG antibodies in children seeking medical care in Seattle, WA June 2020 to December 2022.","authors":"Amanda L Adler, Alpana Waghmare, Kirsten Lacombe, Jane A Dickerson, Alexander L Greninger, Melissa Briggs Hagen, Kimberly Pringle, Tarayn Fairlie, Claire M Midgely, Janet A Englund","doi":"10.1128/spectrum.02625-24","DOIUrl":"10.1128/spectrum.02625-24","url":null,"abstract":"<p><p>Seroprevalence studies play an important role in estimating the number of children infected with SARS-CoV-2. We report SARS-CoV-2 seroprevalence in children seeking medical care for any reason at a free-standing pediatric hospital in Seattle, WA over a 2.5-year period and four distinct pandemic waves. We randomly selected residual serum samples from children and young adults seeking medical care as inpatients and outpatients at Seattle Children's Hospital between June 2020 and December 2022 to test for the presence of anti-nucleocapsid (N) antibodies. Samples were categorized into four distinct pandemic waves based on Washington State epidemiology: Wave 1 (June 2020-October 2020), Wave 2 (November 2020-June 2021), Wave 3 (July 2021-November 2021), and Wave 4 (December 2021-December 2022). Patient characteristics and COVID-19 vaccine status were obtained, and zip codes were used to ascertain the Social Vulnerability Index (SVI). Multivariable Poisson regression models with robust variance estimates were used to examine the relationship between patient characteristics and anti-N-positivity for each wave. Among 8,040 samples from 7,102 patients included in the analyses, seroprevalence rose from 2.4% (95% CI, 2.0%-3.1%) in Wave 1 to 25.5% (95% CI 23.3%-27.8%) in Wave 4 (following the Omicron surge). High SVI, Hispanic ethnicity, or use of government insurance was associated with increased anti-N positivity in most waves. We observed a steady increase in anti-N seroprevalence followed by a sharp increase after the Omicron surge in early 2022. Our data demonstrate the burden of COVID-19 on specific groups with health disparities within our region throughout the pandemic.IMPORTANCEOur results highlight the importance of seropositivity studies as essential tools to provide information on the incidence and prevalence of SARS-CoV-2 seropositivity. Our results also reinforce other reports demonstrating the inequitable burden of COVID-19 on groups with health disparities and that this inequitable burden continued to persist throughout the pandemic, even in a region with high adherence to COVID-19 mitigation efforts. It also highlights SVI's value in identifying communities that must be part of pandemic research, and public health and vaccination strategies.</p>","PeriodicalId":18670,"journal":{"name":"Microbiology spectrum","volume":" ","pages":"e0262524"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11960482/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}