Vaccines最新文献

{"title":"Effect of Inoculation Volume on a Mouse Model of Influenza Virus Infected with the Same Viral Load.","authors":"Yali Sun, Yuwei Wei, Xuelian Han, Yuan Wang, Qi Yin, Yuhang Zhang, Tiantian Yang, Jiejie Zhang, Keyu Sun, Feimin Fang, Shuai Zhang, Kai Yuan, Min Li, Guangyu Zhao","doi":"10.3390/vaccines13020173","DOIUrl":"10.3390/vaccines13020173","url":null,"abstract":"<p><strong>Background: </strong>Influenza is a highly contagious respiratory disease that poses significant health and economic burdens. Mice are commonly used as animal models for studying influenza virus pathogenesis and the development of vaccines and drugs. However, the viral volume used for nasal inoculation varies substantially in reported mouse influenza infection models, and the appropriate viral dose is crucial for reproducing experimental results.</p><p><strong>Methods: </strong>Mice were inoculated with mouse lung-adapted strains of influenza virus A/Puerto Rico/8/34 (H1N1) via intranasal administration of 10 μL, 20 μL, and 40 μL at doses of 200 plaque-forming units (PFU) and 2000 PFU. This study investigated the impact of varying viral inoculum volumes on murine outcomes at identical doses and assessed the disparities across diverse dosage levels.</p><p><strong>Results: </strong>Regarding weight change trajectories, mortalities, lung tissue viral titers, and pathological manifestations, the group that received the 40 μL inoculation volume within the low-dose infection mice (200 PFU) manifested a statistically significant divergence from those inoculated with both the 10 μL and 20 μL volumes. Within the context of high-dose infections (2000 PFU), groups that received inoculation volumes of 20 μL and 40 μL exhibited marked disparities when compared to those receiving the 10 μL volume.</p><p><strong>Conclusions: </strong>Disparities in inoculation volume, even under uniform infection dosages, engender differential outcomes in pathogenicity. Of particular note, the viral replication efficacy at a 20 μL inoculation volume demonstrates conspicuous fluctuations across diverse infection dose regimens.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860169/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increasing Prevalence of Occult HBV Infection in Adults Vaccinated Against Hepatitis B at Birth.","authors":"Ge Zhong, Zhi-Hua Jiang, Xue-Yan Wang, Qin-Yan Chen, Lu-Juan Zhang, Li-Ping Hu, Mei-Lin Huang, Yu-Bi Huang, Xue Hu, Wei-Wei Zhang, Tim J Harrison, Zhong-Liao Fang","doi":"10.3390/vaccines13020174","DOIUrl":"10.3390/vaccines13020174","url":null,"abstract":"<p><strong>Background/objectives: </strong>Immunization with the hepatitis B vaccine is the most effective means of preventing acute HBV infection. However, whether the primary vaccination of infants confers lifelong immunity remains controversial. Therefore, the ongoing surveillance of vaccine recipients is required.</p><p><strong>Methods: </strong>A longitudinal study was carried out based on LongAn county, one of the five clinical trial centers for hepatitis B immunization in China in the 1980s. Serum samples were collected and tested for HBV serological markers and DNA.</p><p><strong>Results: </strong>A total of 637 subjects born in 1987-1993 were recruited, including 503 males and 134 females. The total prevalence of HBsAg was 3.9%. The prevalence in females (8.2%) was significantly higher than that in males (2.8%) (<i>p</i> = 0.004). The prevalence of anti-HBc in females (52.2%) was also significantly higher than that in males (41.2%) (<i>p</i> = 0.021). The prevalence of anti-HBs was 42.7% and did not differ significantly between males (41.7%) and females (46.3%) (<i>p</i> = 0.347). Compared to data from surveillance over the last ten years, the positivity rate of HBsAg did not increase. The positivity rate of anti-HBs decreased significantly (<i>p</i> = 0.049) while that of anti-HBc increased significantly (<i>p</i> = 0.001). The prevalence of occult HBV infection (OBI) in 2024 (6.0%) was significantly higher than that in 2017 (1.6%) (<i>p</i> = 0.045). Subjects diagnosed with OBI in 2017 maintained occult infection in 2024.</p><p><strong>Conclusions: </strong>Neonatal HBV vaccination maintained effective protection for at least 37 years. However, the prevalence of OBI increases with age in those vaccinated at birth, raising a new issue of how to prevent and control OBI in the post-universal infant vaccination era.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860204/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Efficacy and Safety of Simultaneous Vaccination with Polysaccharide Conjugate Vaccines Against Pneumococcal (13-Valent Vaccine) and <i>Haemophilus influenzae</i> Type b Infections in Children with Juvenile Idiopathic Arthritis Without Systemic Manifestations: A Prospective Cohort Study.","authors":"Ekaterina Alexeeva, Tatyana Dvoryakovskaya, Anna Fetisova, Ivan Kriulin, Elizaveta Krekhova, Anna Kabanova, Vladimir Labinov, Elizaveta Labinova, Mikhail Kostik","doi":"10.3390/vaccines13020177","DOIUrl":"10.3390/vaccines13020177","url":null,"abstract":"<p><p><b>Background</b>: Immunosuppressive therapy (methotrexate and biological agents) for juvenile idiopathic arthritis (JIA) is associated with an increased risk of severe infections, higher infection rates, treatment interruptions, failure to achieve disease remission, and recurrent disease flares. Our study aimed to evaluate the safety and efficacy of simultaneous immunization with 13-valent polysaccharide conjugate vaccines (PCV13) against <i>S. pneumoniae</i> (SP) and <i>Hemophilus influanzae</i> type b infections (HibV) in children with JIA without systemic manifestations. <b>Methods</b>: A total of 371 non-systemic JIA patients who received 13PCV and HibV were included in this prospective cohort study. In every patient, we evaluated clinical, laboratory, anti-SP, and anti-Hib IgG antibodies before vaccination, three weeks after, and six months after, and all adverse events (AEs) were collected during the study. The number and duration of acute respiratory infection (ARI) episodes and requirements for antibacterial treatment and AE six months before and after the baseline were collected. <b>Results</b>: The levels of the Ig G anti-SP and anti-Hib antibodies increased in the 3 weeks after vaccination; then, anti-SP antibodies slightly decreased and anti-Hib antibodies remained increased during the whole study, as well as in a part of the patients with a protective titer. During the study, there were no patients with significant flares, and the main JIA outcomes gradually decreased during the trial. The number of patients with uveitis remained equal, as well as the part of the patients with active, low-active, and inactive uveitis. There was no significant rise in the hs-CRP or S100 protein after the vaccination. Previous or ongoing treatment with non-biological (<i>p</i> = 0.072) and biological (<i>p</i> = 0.019) disease-modified anti-rheumatic drugs affected the Hib and did not affect the anti-SP protective titer at the end of the study. Within 6 months following vaccination, the number of ARI episodes (<i>p</i> < 0.001) and the number of courses of antibacterial treatment (<i>p</i> < 0.0001) decreased twice. The median duration of ARI episodes decreased four times (<i>p</i> < 0.0001). Mild AEs (injection site reactions and short-term fever episodes) were found in 58 (15.6%) patients with JIA, and 1 patient (0.2%) developed an SAE. <b>Conclusions</b>: Simultaneous vaccination against pneumococcal and Hib infections reduces the frequency and duration of episodes of ARI, as well as the number of courses of antibacterial drugs, and does not lead to significant JIA flares. The number of reported AEs is consistent with what was expected.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nirsevimab Prophylaxis for Reduction of Respiratory Syncytial Virus Complications in Hospitalised Infants: The Multi-Centre Study During the 2023-2024 Season in Andalusia, Spain (NIRSEGRAND).","authors":"David Moreno-Pérez, Aleksandra Korobova, Francisco de Borja Croche-Santander, Ana Cordón-Martínez, Olga Díaz-Morales, Leticia Martínez-Campos, Elena Pérez-González, María Del Carmen Martínez-Padilla, Juan Luis Santos-Pérez, Jaime Brioso-Galiana, María Isabel Sánchez-Códez, Jorge Del Diego-Salas, Mario Rivera-Izquierdo, Nicola Lorusso","doi":"10.3390/vaccines13020175","DOIUrl":"10.3390/vaccines13020175","url":null,"abstract":"<p><strong>Background: </strong>Nirsevimab was indicated in a population level for all infants < 6 months during the 2023-2024 season in Andalusia (southern Spain). Our aim was to analyse the effect of nirsevimab in the reduction in complications in infants hospitalised for RSV bronchiolitis.</p><p><strong>Methods: </strong>A retrospective observational cohort study was conducted in nine relevant hospitals from all provinces of Andalusia, a region with over 9 million inhabitants. The study sample included 222 children, divided into two groups: infants administered with nirsevimab for passive immunisation (exposure) and infants not administered with nirsevimab. Clinical outcomes were analysed, including the use of respiratory support, the need for admission to paediatric intensive care unit (PICU), and duration of hospitalisation. Bivariate analyses were performed, and multivariable logistic regression models were designed to calculate adjusted odds ratios (ORa), and Cox regression models to calculate adjusted hazard ratios (HRa).</p><p><strong>Results: </strong>Bivariate analysis showed an association between passive immunisation with nirsevimab and a lower frequency of numerous outcomes. After adjustment for relevant covariates, multivariable models showed that the exposure (nirsevimab) reduced nasal cannula use by 64% (13-85%), invasive or non-invasive mechanical ventilation by 48% (1-73%), PICU admission by 54% (14-75%), length of hospitalisation by 30% (8-47%), and length of nasal cannula by 31% (7-49%). A higher risk of co-infection was observed in those immunised (aOR = 3.42, 95%CI: 1.52-7.68).</p><p><strong>Conclusions: </strong>Passive immunisation with nirsevimab may decrease the severity of RSV bronchiolitis in infants requiring hospitalisation, thus contributing tertiary prevention that extends beyond the prevention of RSV infection.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11861336/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COVID-19 Vaccination and Acute Anterior Uveitis-A Case Control Study.","authors":"Asaf Shemer, Amit Toledano, Aya Altarescu, Biana Dubinsky-Pertzov, Assaf Rozenberg, Idan Hecht, Adi Einan-Lifshitz, Eran Pras","doi":"10.3390/vaccines13020176","DOIUrl":"10.3390/vaccines13020176","url":null,"abstract":"<p><strong>Objective: </strong>To evaluate the association between the BNT162b2 (Pfizer-BioNTech^®) coronavirus disease vaccine and new-onset anterior uveitis.</p><p><strong>Methods: </strong>A retrospective case control study of patients admitted and diagnosed with new-onset acute anterior uveitis, and matched controls admitted for other reasons (1:3 ratio), was completed. Rates of exposure to the BNT162b2 vaccine were compared between groups, and odds ratios for exposure to the vaccine were calculated. A secondary analysis of the overall number of patients with new-onset anterior uveitis in the six preceding years was conducted. This study was conducted in one academic center in Israel.</p><p><strong>Results: </strong>A total of 16 patients were admitted for acute anterior uveitis during the study period. Of the 16 cases, 11 (69%) received the first dose of the BNT162b2 vaccine prior to presentation and 8 (50%) also received the second dose. This compares to 39 (81.2%) in the control group. The odds ratio for exposure to the vaccine among cases was 0.508 (95% confidence interval 0.141-1.829, <i>p</i> = 0.300). Compared with preceding years, the rate of cases diagnosed with acute anterior uveitis in 2021 was similar to the six preceding years (mean 11.8 ± 3.4 cases).</p><p><strong>Conclusions: </strong>In this case control study and comparison with preceding years, we found no evidence to suggest an association between vaccination with the BNT162b2 (Pfizer-BioNTech^®) COVID-19 vaccine and new-onset acute anterior uveitis.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860193/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human Papillomavirus Infection in Partners of Women Attending Cervical Cancer Screening: A Pilot Study on Prevalence, Distribution, and Potential Use of Vaccines.","authors":"Arianna Sucato, Nicola Serra, Michela Buttà, Leonardo Di Gregorio, Daniela Pistoia, Giuseppina Capra","doi":"10.3390/vaccines13020172","DOIUrl":"10.3390/vaccines13020172","url":null,"abstract":"<p><p><b>Background/Objectives</b>: Human Papillomavirus (HPV) cross-infection among couple's partners is a widespread event and could lead to persistent infections. Unfortunately, the influence of male sexual partners of HPV-positive women on their cervical lesions and the potential role of HPV vaccines have been under-investigated. We evaluated the HPV prevalence in male partners of HPV-infected women, focusing on the possible correlation between partners' cervical lesions and the role of HPV vaccination. <b>Methods</b>: Two samples, genital and urethral swabs, were collected for each of the 90 patients recruited. HPV-DNA detection was carried out by the Allplex HPV28 detection assay. <b>Results</b>: HPV prevalence was 66.7% (60/90); high-risk HPV (hrHPV) genotypes were detected in 90% (54/60) cases and multiple infections in 55% (33/60). The most frequent hrHPVs were HPV31 (<i>p</i> = 0.0265) and HPV52 (<i>p</i> = 0.002), found in 18.3% (11/60) of cases, and HPV53 (<i>p</i> = 0.0116) in 16.7% (10/60). Statistical analysis showed a higher probability of a less severe cytological diagnosis with the increase in the number of genotypes detected (<i>p</i> = 0.0146). Among the HPV-positive partners of females with cervical lesions, 18.7% (6/32) and 62.5% (20/32) had vaccine genotypes of the quadrivalent and nonavalent vaccines, respectively. The nonavalent vaccine showed a significantly higher potential to prevent lesions (62.5% vs. 18.7%, <i>p</i> = 0.0001), with an absolute additional potential impact (AAI) of 31.1% in histological and 32.4% in cytological diagnoses. <b>Conclusions</b>: These preliminary results provide new insight into the correlation between the number of partner genotypes and the severity of cervical lesions and show promising results for the preventive potential of vaccinating male partners.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11861694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Humoral Immune Response Against COVID-19 Through Vaccination in Hemodialysis Patients.","authors":"Ji Young Park, Seong-Ho Choi, Yong Kwan Lim, Jungho Shin, Soie Kwon, Haein Kim, Jin-Won Chung","doi":"10.3390/vaccines13020170","DOIUrl":"10.3390/vaccines13020170","url":null,"abstract":"<p><strong>Background: </strong>This study investigated the humoral responses to SARS-CoV-2 in hemodialysis (HD) patients. The clearance of molecules in the blood during hemodialysis is influenced by factors such as filter pore size, flow rate, operating pressure, and treatment duration. Chronic kidney disease patients often show low antibody titers for pathogens like pneumococcus, influenza virus, and hepatitis B virus.</p><p><strong>Methods: </strong>In this study, the surrogate virus neutralization test (sVNT) for the wild type (WT) and Omicron variants, as well as spike-specific IgG levels, were measured at two time points (May 2022 and December 2023). Medical records and questionnaires were used to gather participant information.</p><p><strong>Results: </strong>A total of 26 HD patients were enrolled, including 3 on immunosuppressive therapies. A total of 8 patients had COVID-19 during the first sampling, and 19 during the second. The results showed that sVNT levels for WT decreased over time, though positivity remained at 100% during both sampling periods. In contrast, sVNT levels for Omicron increased significantly, with positivity rising from 46.2% to 75.0% (<i>p</i> < 0.05). Spike-specific IgG levels also increased, with positivity improving from 96.2% to 100%. Patients on immunosuppressive therapies had significantly lower sVNT levels for both WT and Omicron in the second period (<i>p</i> < 0.05), though no significant differences were observed during the first period.</p><p><strong>Conclusion: </strong>HD patients, particularly those on immunosuppressive therapies, showed reduced and declining neutralizing responses over time. A meta-analysis of HD patients seems necessary to determine whether all dialysis patients need COVID-19 booster vaccinations, similar to the hepatitis B vaccine, highlighting the need for targeted vaccination strategies.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11862019/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adherence to Palivizumab for Respiratory Syncytial Virus Prophylaxis in Romanian Infants.","authors":"Andreea Calomfirescu-Avramescu, Adrian Ioan Toma, Claudia Mehedințu, Leonard Năstase, Vlad Dima","doi":"10.3390/vaccines13020171","DOIUrl":"10.3390/vaccines13020171","url":null,"abstract":"<p><strong>Background: </strong>In 2022, Romania started an RSV immunoprophylaxis program with Palivizumab for infants at high risk: preterm infants born before 35 weeks of pregnancy, infants born with congenital heart defects, and infants with chronic lung disease. We evaluated treatment adherence from August 2022 to March 2024.</p><p><strong>Method: </strong>We monitored the increase in the number of patients enrolled in the program and the number of collaborating neonatologists, family doctors, and pediatricians. Adherence to all doses of Palivizumab in enrolled patients was assessed by telephone interviews. The factors contributing to reduced adherence were identified.</p><p><strong>Results: </strong>Between August 2022 and March 2024, 1903 patients and 233 specialists were enrolled, a steady increase in both cohorts. The percentage of patients that complete their full sequence of doses decreases along with the number of doses (99% for one dose, 73% for two doses, 47% for three doses, 35% for four doses, and 22% for five doses) due to several factors.</p><p><strong>Conclusions: </strong>The program remains highly regarded by both physicians and caregivers, demonstrating its effectiveness as a valuable resource for educating parents and facilitating monoclonal antibody administration as a prevention method for RSV.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11861343/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of Inactivated Bivalent SARS-CoV-2 Vaccines Targeting Ancestral Strain (ERAGEM), Delta, and Omicron Variants.","authors":"Busra Kaplan, Shaikh Terkis Islam Pavel, Muhammet Ali Uygut, Merve Tunc, Yesari Eroksuz, Ilhami Celik, Esma Eryilmaz Eren, Gulay Korukluoglu, Ates Kara, Aykut Ozdarendeli, Hazel Yetiskin","doi":"10.3390/vaccines13020169","DOIUrl":"10.3390/vaccines13020169","url":null,"abstract":"<p><strong>Background/objectives: </strong>The rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the emergence of variants with enhanced transmissibility and immune evasion, challenging existing vaccines. This study aimed to evaluate the immunogenicity and protective efficacy of inactivated bivalent vaccine formulations incorporating the ancestral SARS-CoV-2 strain (ERAGEM) with either Delta or Omicron (BA.5) variants.</p><p><strong>Methods: </strong>Bivalent vaccine formulations were prepared using beta-propiolactone-inactivated SARS-CoV-2 antigens and administered to K18-hACE2 transgenic mice. Following prime and booster immunizations, neutralizing antibody titers and viral loads were assessed through ELISA, microneutralization assays, and quantitative PCR. Mice were challenged with the respective variants, and the survival rates, temperature, and body weight changes were monitored for 21 days.</p><p><strong>Results: </strong>Both vaccine formulations elicited significant increases in neutralizing antibody titers post-booster immunization. The ERAGEM + Delta group demonstrated geometric mean titers (GMTs) of 6938.1 and 4935.0 for the ancestral and Delta variants, respectively, while the ERAGEM + Omicron (BA.5) group achieved GMTs of 16,280.7 and 24,215.9 for the ancestral and Omicron (BA.5) variants. Complete survival (100%) was observed in all the vaccinated groups post-challenge, with no detectable viral titers in the lungs and substantial reductions in the nasal turbinate viral loads compared to the unvaccinated controls.</p><p><strong>Conclusions: </strong>The bivalent inactivated vaccines demonstrated strong immunogenicity and complete protection against severe disease in preclinical models. These findings indicate the potential of bivalent vaccine strategies in addressing antigenic diversity and preparing for future pandemics caused by rapidly evolving pathogens.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11861512/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced and Prolonged Immunogenicity in Mice of Thermally Stabilized Fatty Acid-Conjugated Vaccine Antigen.","authors":"Bo Mi Kim, Yeon-Ho Kim, Hai V Ngo, Hy D Nguyen, Chulhun Park, Beom-Jin Lee","doi":"10.3390/vaccines13020168","DOIUrl":"10.3390/vaccines13020168","url":null,"abstract":"<p><strong>Background/objectives: </strong>Influenza vaccines require good thermal stability without the need for refrigerator storage. Although the fatty acid-conjugated hemagglutinin (Heg) vaccine antigen provides good stability in both solid and liquid states, its therapeutic effectiveness must be validated in vivo. This study aimed to investigate the immunogenicity of the thermally stabilized Heg-oleic acid conjugate (HOC) and compare it with native Heg as a reference.</p><p><strong>Method: </strong>To evaluate HOC immunogenicity, an enzyme-linked immunosorbent assay was used to measure hemagglutinin inhibition (HI) titers, serum IgG antibody titers (IgG1, IgG2a), and cytokine secretion levels (IFN-γ, IL-4) in BALB/c mice after intramuscular (IM) injection.</p><p><strong>Results: </strong>Thermally stabilized HOC induced higher and more sustained serum IgG1 and IgG2a responses than the native Heg vaccine antigen. IgG1 is typically associated with a Th2 response, whereas IgG2a is associated with a Th1 response. HOC appeared to enhance both responses, inducing a more balanced immune response. Moreover, HOC antigens stimulate broader immune responses, suggesting stronger and longer-lasting immune memory. The cytokine levels of IFN-γ (2.8-fold) and IL-4 (6-fold) were significantly increased in the HOC-immunized group compared to the Heg group. IFN-γ, a cytokine that activates the Th1 immune response, demonstrated the enhanced ability of HOC to induce a Th1 response. IL-4, a cytokine that promotes the Th2 response, indicated that HOC also strongly induced a Th2 response. The thermal stability of HOC antigens was crucial for maintaining their structural integrity, enabling the continuous exposure to the stable antigen without denaturation. This allows immune cells to recognize stable antigens efficiently and form long-term immune memory.</p><p><strong>Conclusions: </strong>The stability of HOC antigens enhanced the antigen processing efficiency of antigen-presenting cells (APCs) and stimulated immune responses. The fatty acid-conjugated vaccine antigen could provide improved storage stability but also enhance immunogenic efficacy compared to the native antigen, supporting its potential for further applications.</p>","PeriodicalId":23634,"journal":{"name":"Vaccines","volume":"13 2","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860450/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143504230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}