Immunostimulant Research Articles

Effects of Red Clover Isoflavones on Growth Performance, Immune Function, and Cecal Microflora of Mice

Isoflavone components extracted from red clover have anti-inflammatory, antioxidant and immune boosting effects. We hypothesize that red clover isoflavones (RCIs) achieve health-promoting effects via altering the gut microbiota. A total of 48 mice (20 ± 2 g) were randomly divided into a control group, low-dose group (0.05% RCIs in feed), middle-dose group (0.1% RCIs in feed), and high-dose group (0.2% RCIs in feed) with 12 mice per group. The feeding period was 20 d. The results showed that RCIs can increase the daily gain and decrease the ratio of feed to gain in mice. The organ indexes and blood biochemical indexes of the mice in each RCI group were in the normal range, indicating that RCIs do not damage liver or kidney function. RCI supplementation increased serum immunity and altered the microbial community structure in the cecum of the mice. RCIs can increase the diversity of beneficial bacteria such as Bacteroidaceae, Muribaculaceae, and Akkermansiaceae, and reduced the pathogenic Staphylococcaceae. Therefore, supplementing the diet with RCIs results in improved growth performance and notable alterations in the cecal microbiota in mice, and has potential applications as a feed additive to improve livestock production.

Dynamic Changes and Trends of SARS-CoV-2 Antibodies Induced by Infection and Vaccination Across Multiple Time Points.

As the COVID-19 pandemic continues, increasingly complex vaccination and infection histories have made it urgent to investigate the antibody dynamics in populations with hybrid immunity. This study aimed to explore the multi-time-point dynamics of SARS-CoV-2 IgG antibody levels in a community-based population in Jiangsu Province, China, following the Omicron BA.5 wave, as well as the long-term persistence of IgG antibodies nearly 2 years postinfection. A total of 2737 participants across Jiangsu Province were followed up at three different time points over a 6-month period (December 2022-June 2023). Additionally, a cross-sectional serological survey was conducted in October 2024, involving 230 participants to assess long-term antibody persistence. We used generalized additive models to fit antibody dynamics curves, generalized linear mixed models to explore factors influencing antibody levels, and Kaplan-Meier survival analysis to estimate cumulative seroreversion rates. Our findings revealed that, following the large-scale Omicron BA.5 infections, over 85% of the population initially exhibited seropositive IgG levels. Older individuals (> 65 years) had significantly lower antibody levels and faster rates of decline compared to younger participants. Booster immunization reduced the risk of seroreversion by 59.79% (95% CI: 29.63%-76.46%), while individuals with multiple infections experienced slower antibody decay. In the cross-sectional survey conducted 22 months postinfection, the IgG seropositivity rate remained high, exceeding 98%, indicating sustained immunity at the population level. This study provides valuable insights into the dynamics and persistence of IgG antibody levels following large-scale infection. The results underscore the importance of tailored booster immunization strategies to sustain long-term immunity, especially in vulnerable groups like the elderly. Additionally, ongoing serological monitoring is essential for assessing population immunity and informing future vaccination strategies.

Immunogenicity and safety of Vero cell culture-derived Japanese encephalitis vaccine: a phase 3 study in Chinese infants

ABSTRACT Background Japanese encephalitis (JE) is a severe infectious disease of the central nervous system. Vaccination with Vero cell culture-derived vaccines may effectively reduce JE incidence. Research Design and Methods In this single-center, randomized, blinded, positive-controlled clinical trial in China involving 600 healthy infants aged 6–11 months, participants were divided into experimental and control groups administered JEV-PI and JEV-LI, respectively. Antibody titers were determined after 0- and 7-day immunization schedules. A booster dose followed 12 months later. Results After primary vaccination and before booster vaccination, the positive conversion rate, geometric mean titer (GMT), and geometric mean increase (GMI) of JEV-PI-neutralizing antibodies exceeded those of JEV-LI. After booster immunization, the GMT and GMI of JEV-PI were higher than those of JEV-LI. After primary immunization, the local, systemic, and overall adverse reactions were of grades 1 and 2, with a low incidence of grade 3. After booster immunization, these differences were mainly grades 1 and 2, with no differences between JEV-PI and JEV-LI. Conclusion JEV-PI is a promising vaccine as infants acquired long-lasting and highly neutralizing immune antibodies after inoculation with JEV-PI. Trial Registration The trial was registered in the Chinese Clinical Trial Registry (https://www.chictr.org.cn/showproj.html?proj = 203130; registration number: ChiCTR2300074692; registration date: 14/08/2023).

Analisis Ayat-Ayat Al-Qur’an tentang Jahe untuk Kesehatan dalam Perspektif Al-Quran dan Sains

This study aims to analyze Quranic verses that mention ginger (Zingiber officinale), particularly in Surah Al-Insan [76:17], and to examine its benefits from both a modern scientific and Islamic spiritual perspective. The study employs a qualitative method with a descriptive-analytical approach and thematic tafsir (maudhu'i). The primary data sources include the Qur'an and tafsir literature, while secondary sources consist of scientific research on the bioactive compounds in ginger, such as gingerol, shogaol, and zingerone. The results indicate that ginger has significant health benefits, including antioxidant and anti-inflammatory effects, immune system enhancement, and prevention of degenerative diseases such as cancer and cardiovascular diseases. From a spiritual perspective, the mention of ginger in the Qur'an as a drink for the inhabitants of paradise symbolizes the balance between physical and spiritual blessings. The integration of Quranic teachings and modern science affirms that ginger is a blessed plant, reminding humans of the importance of maintaining health as an expression of gratitude to Allah SWT. This study contributes to a deeper understanding of the relationship between scientific knowledge and revelation, while encouraging the use of herbal plants to improve quality of life.

Genome Sequencing Providing Molecular Evidence of Tetrapolar Mating System and Heterothallic Life Cycle for Edible and Medicinal Mushroom Polyporus umbellatus Fr.

Polyporus umbellatus is a species whose sclerotia have been extensively employed in traditional Chinese medicine, which has diuretic, antitumor, anticancer, and immune system enhancement properties. However, prolonged asexual reproduction has resulted in significant homogenization and degeneration of seed sclerotia. In contrast, sexual reproduction has emerged as an effective strategy to address these challenges, with a distinct mating system serving as the foundation for the implementation of sexual breeding. This study presents the first sequencing and assembly of the genome of P. umbellatus, thereby providing an opportunity to investigate the mating system at the genomic level. Based on the annotated mating-type loci within the genome, monokaryotic offspring exhibiting different mating-types were identified. Through the integration of traditional mating tests, the tetrapolar mating system of P. umbellatus was distinctly elucidated. The resequencing of monokaryotic strains with four different mating-types, along with comparative analyses of mating-type loci, revealed the HD1 and HD2 (HD, homeodomain) genes determined the mating A types, and the PR4, PR5, and PR6 (PR, pheromone receptor) genes determined the mating B types. Meanwhile, this study offers a successful case study in the molecular investigation of mating systems. Additionally, the number of sterigma and basidiospores on each basidium was examined using scanning electron microscopy, while the nuclei of basidiospores and basidia at various developmental stages were analyzed through DAPI staining. This research clarifies the heterothallic life cycle of P. umbellatus. The findings of this study are expected to facilitate advancements in genetic research, breeding development, strain improvement, and the industry of P. umbellatus.

Effects and Impact of Selenium on Human Health, A Review.

Selenium (Se) is an essential trace element that is crucial for human health. As a key component of various enzymes and proteins, selenium primarily exerts its biological functions in the form of selenoproteins within the body. Currently, over 30 types of selenoproteins have been identified, with more than 20 of them containing selenocysteine residues. Among these, glutathione peroxidases (GPXs), thioredoxin reductases (TrxRs), and iodothyronine deiodinases (DIOs) have been widely studied. Selenium boasts numerous biological functions, including antioxidant properties, immune system enhancement, thyroid function regulation, anti-cancer effects, cardiovascular protection, reproductive capability improvement, and anti-inflammatory activity. Despite its critical importance to human health, the range between selenium's nutritional and toxic doses is very narrow. Insufficient daily selenium intake can lead to selenium deficiency, while excessive intake carries the risk of selenium toxicity. Therefore, selenium intake must be controlled within a relatively precise range. This article reviews the distribution and intake of selenium, as well as its absorption and metabolism mechanisms in the human body. It also explores the multiple biological functions and mechanisms of selenium in maintaining human health. The aim is to provide new insights and evidence for further elucidating the role of selenium and selenoproteins in health maintenance, as well as for future nutritional guidelines and public health policies.

Vaccination with a DNA vaccine cocktail encoding TgROP2, TgROP5, TgROP9, TgROP16, TgROP17, and TgROP18 confers limited protection against Toxoplasma gondii in BALB/c mice.

Toxoplasmosis is a foodborne zoonotic parasitic disease caused by Toxoplasma gondii, which seriously threatens to human health and causes economic losses. At present, there is no effective vaccine strategy for the prevention and control of toxoplasmosis. T. gondii rhoptry proteins (ROPs) are important proteins secreted by the parasite during the early stage of invasion into host cells. In this study, we constructed six individual plasmids (pVAX1-ROP2, pVAX1-ROP5, pVAX1-ROP9, pVAX1-ROP16, pVAX1-ROP17, and pVAX1-ROP18) encoding T. gondii rhoptry proteins and then used an equimolar amount of each as a vaccine cocktail. Following booster immunization, serum antibody levels, splenic lymphocyte proliferation, cytokine production, and survival time after infection with T. gondii RH strain were measured in immunized mice. The results showed that the mice immunized with the DNA vaccine cocktail developed a higher level of the specific anti-T. gondii IgG in serum and the cytokines such as IFN-γ, IL-2, IL-12, and IL-4 (P < 0.01). The stimulation index (SI) of spleen lymphocytes (P < 0.01), the frequencies of CD4+ T lymphocytes (P < 0.01), and the ratio of CD4+/CD8+ T lymphocytes (P < 0.05 or P < 0.01) in the vaccine-immunized mice were significantly increased compared to the control group. After challenge with the virulent T. gondii RH strain tachyzoites, the survival time of mice in the DNA vaccine cocktail group (18.1 ± 1.81 d) was significantly longer (P < 0.01) than that in the control group (8.4 ± 1.02 or 7.9 ± 0.83 d). The results indicated that the DNA vaccine cocktail could elicit strong humoral and cellular immune responses in mice and could also improve the resistance of mice to acute T. gondii infection.

A Pool of Bacterium-like Particles Displaying African Swine Fever Virus Antigens Induces Both Humoral and Cellular Immune Responses in Pigs

Background/Objectives: African swine fever (ASF), caused by African swine fever virus (ASFV), poses a significant threat to the global swine industry. This underscores the urgent need for safe and effective ASF vaccines. Methods: Here, we constructed five bacterium-like particles (BLPs) that each display one of the five ASFV antigens (F317L, H171R, D117L, B602L, and p54) based on the Gram-positive enhancer matrix-protein anchor (GEM-PA) system. GEM is a bacterial particle that contains only peptidoglycan, while PA is composed of three lysin motifs (Lysm) derived from the C-terminus of the AcmA protein, capable of non-covalently binding to GEM. By fusing the ASFV antigens with PA, the ASFV antigens can be firmly attached to the surface of GEM. Subsequently, the piglets were immunized via intramuscular injection with a mixture of BLPs-F317L, BLPs-H171R, BLPs-D117L, BLPs-B602L, and BLPs-p54. Results: The results showed that the piglets developed detectable serum IgG antibodies 2 weeks after the first immunization, and these high antibody levels were maintained 4 weeks after the booster immunization. Moreover, these piglets produced more IFN-γ-producing lymphocytes than the control piglets. Conclusions: The data indicate that the generated BLPs mixture can stimulate both humoral and cellular immune responses in piglets, these five ASFV proteins are promising antigens, and the BLPs generated represent candidate ASF vaccines.

Study on the Development of Kangtai Biologicals in the Context of the COVID-19 Pandemic--Analysis Based on Financial Indicators

According to data from the National Health Commission, as of July 23, 2022, China's full basic immunization rate was 89.7% and booster immunization rate was 71.7%. Among them, the vaccination rate of at least one dose of vaccine for the elderly over 60 years old was 89.6%, the full immunization rate was 84.7%, and the booster immunization rate was 67.3%, and the new crown vaccine has almost reached market saturation. The Novel Coronavirus Pneumonia background, the vaccine industry is facing the new crown vaccine demand instability, the second type of vaccine government supervision is small, social responsibility events occur frequently (Changsheng Biological vaccine counterfeiting events, Beijing Kexing bribery case) and high R &amp; D investment risk, so, based on the Contagious Biological face technology, patents, production capacity and so on a number of barriers, resulting in the decline in performance of the status quo, how to adjust the strategic direction in a timely manner also become a major test. Whether it will change accounting policies to “do high” performance? How about the direction of future development? Is very worth studying. In this paper, we will take Kangtai Bio as a case study, analyze the relevant indexes of its operation ability and development ability, explore the problems in its current development, and put forward relevant suggestions.

Analysis of Factors Attributing to Hepatitis B Vaccine Non-response

Currently, 5-15% of hepatitis B vaccine recipients are non-responders despite the high global coverage 83% of the hepatitis B vaccine. The research of hepatitis B vaccine nonresponse had been going on for some time for the improvement of the vaccine and the objective to eliminate hepatitis B, this paper aims to summarize some of the factors contributing to hepatitis B vaccine nonresponse base of these previous studies after scrutiny. Factors contributing to hepatitis B vaccine nonresponse including HLA haplotypes, age, elder with comorbid condition, obesity, smoking, presence of micronutrient deficiency is involved in this paper. The understanding of these factors is important for the further progression of the vaccine, improvements like repeated vaccination, a booster dose, use of immune boosters, vaccine with a higher dosage, a different adjuvant, a more effective antigen, a different administration route of the vaccine, change of needle length when injecting the vaccine can be made considering the nonresponse factors, therefore increasing the efficacy of hepatitis B vaccine.

SARS-CoV-2-vaccination in primary humoral immunodeficiency - Experience from a German lung clinic.

During the COVID-19 pandemic the effectiveness of vaccines against SARS-CoV-2 in immunodeficient patients did not only affect the individual risk of these vulnerable patients but endangered the selection of new variants of concern due to prolonged virus shedding by these patients. In a tertiary center for pulmonary diseases, we investigated the immune response of 11 patients with primary humoral immunodeficiency and 13 healthy controls on the humoral and cellular level after full vaccination with a mRNA or vector vaccine against SARS-CoV-2. In the majority of patients (73%), we found antibodies against the Spike protein above the thresh-old of positivity. Likewise, patients showed a promising cellular response: the upregulated production of INFγ, TNFα and CXCL10 by T cells did not differ from the response of healthy controls. These results stress the importance to further discern an adequate immunological correlate of protection and the need to follow the effect of booster immunizations in this population at risk.

A Phosphatidyl Conjugated Telomerase-Dependent Telomere-Targeting Nucleoside Demonstrates Colorectal Cancer Direct Killing and Immune Signaling.

Telomerase and telomeres are crucial in cancer cell immortalization, making them key targets for anticancer therapies. Currently, 6-thio-dG (THIO) combined with the anti-PD-1 inhibitor Cemiplimab is under phase II clinical investigation (NCT05208944) in NSCLC patients resistant to prior immunotherapies. This study presents the design, synthesis, and evaluation of novel bimodular conjugate molecules combining telomere-targeting nucleoside analogs and phosphatidyl diglyceride groups. Among them, dihexanoyl-phosphatidyl-THIO (diC6-THIO) showed high anticancer activity with sub-µM EC50 values in vitro across various cancer cell lines. In mouse colorectal cancer models, diC6-THIO demonstrated strong anticancer effects alone and in combination with PD1/PD-L1 inhibitors. Administration of this compound resulted in the efficient formation of Telomere dysfunction Induced Foci (TIFs) in vitro, indicating an on-target, telomerase-mediated telomere-modifying mechanism of action for the molecule. Systemic treatment also activated CD4+ and CD8+ T cells while reducing regulatory T cells, indicating immune system enhancement. Notably, diC6-THIO exhibits an improved solubility profile while maintaining comparable anticancer properties, further supporting its potential as a promising therapeutic candidate. These findings highlight diC6-THIO as a promising telomere-targeting prodrug with dual effects on telomere modification and immune activation.

Formulation And Stability Of Gel Toothpaste With Sungkai Leaf (Peronema Canescens Jack) Extract And Na-Cmc Gelling Agent

The Sungkai leaf (Peronema canescens Jack), which is rich in alkaloids, flavonoids, tannins, and phenolics, has long been used as a natural immune booster, particularly during the pandemic. With increasing concerns over the health risks of fluoride, such as dental fluorosis and systemic toxicity, the demand for natural alternatives in oral care has risen. This study aimed to formulate and evaluate the physical stability of a gel toothpaste containing Sungkai leaf extract by examining the effects of varying concentrations of Na-CMC (Sodium Carboxymethyl Cellulose) as a gelling agent. Using an experimental one-shot case study design, the physical stability of different concentrations of NaCMC (3%, 4%, 5%, and 6%) was assessed. Stability testing was performed on 5 sample formulations per concentration. The tests included organoleptic properties, homogeneity, pH, foam height, and viscosity over four weeks. The results showed that all formulations met the Indonesian National Standard (SNI No.12-3524-1995), with semi-solid consistency, distinctive Sungkai odor, and slightly bitter taste. The average pH ranged from 6.42 to 6.84, the foam heights were stable, and the viscosity increased with higher Na-CMC concentrations, confirming the stability of the formulation. These findings suggest that natural Sungkai leaf-based toothpaste could provide a promising alternative to traditional fluoride-based products, particularly in markets concerned about chemical ingredients in oral care products.

Medicinal Plants as A Natural Immunity Booster Against Covid 19: A Review

Medicinal plants have long been valued for their therapeutic properties, especially in boosting immune function. This review explores the role of medicinal plants in enhancing immunity during the COVID-19 pandemic, with an emphasis on plants known for their bioactive compounds and health benefits. A thorough search of online databases resulted in the identification of 115 published articles from 2020 to 2024, which led to the selection of 50 plants commonly used for immune support. Plants include Garlic, Ashwagandha, Neem,Turmeric, Guduchi, Holy Basil, Amla, Aloe Vera, Black Cardamom, Cinnamon, Pomegranate, Guava, Moringa, Black Cumin, Lemon, Lemongrass, Papaya, Green Tea and others. These plants contain bioactive compounds such as flavonoids, alkaloids, and terpenoids, which are believed to possess immune-boosting, anti-inflammatory, and antiviral properties. Garlic, Turmeric, and Ashwagandha are particularly noted for combating oxidative stress and supporting immune function, while Gurjo, Neem, and Amla are valued for their detoxifying and anti-inflammatory effects. These plants, traditionally used during viral infections like the flu and COVID-19, represent a fusion of ancient cultural wisdom and modern scientific research.Future research should focus on clinical validation and pharmacological studies to better understand the efficacy of these plants in immune modulation.

Early introduction of IL-10 weakens BCG revaccination’s protection by suppressing CD4+Th1 cell responses

BackgroundThe Bacillus Calmette-Guérin (BCG) vaccine, currently the sole authorized vaccine against tuberculosis (TB), demonstrates limited effectiveness in safeguarding adolescents and adults from active TB, even when administered as a booster with either BCG itself or heterologous vaccine candidates. To effectively control the persistent epidemic of adult TB, it is imperative to investigate the mechanisms responsible for the suboptimal efficacy of the BCG prime-boosting strategy against primary Mycobacterium tuberculosis (M.tb) infection.MethodsC57BL/6J mice were immunized with the BCG vaccine either once or twice, followed by analysis of lung tissue to assess changes in cytokine levels. Additionally, varying intervals between vaccinations and detection times were examined to study IL-10 expression across different organs. IL-10-expressing cells in the lungs, spleen, and lymph nodes were analyzed through FACS and intracellular cytokine staining (ICS). BCG-revaccinated IL-10−/− mutant mice were compared with wild-type mice to evaluate antigen-specific IgG antibody and T cell responses. Protection against M.tb aerosol challenge was evaluated in BCG-revaccinated mice, either untreated or treated with anti-IL-10R monoclonal antibody.ResultsIL-10 was significantly upregulated in the lungs of BCG-revaccinated mice shortly after the booster immunization. IL-10 expression peaked in the lungs 3–6 weeks post-revaccination and was also detected in lymph nodes and spleen as early as 2 weeks following the booster dose, regardless of the intervals between the prime and booster vaccinations. The primary sources of IL-10 in these tissues were identified as macrophages and dendritic cells. Blocking IL-10 signaling in BCG-revaccinated mice—either by using IL-10−/− mutant mice or administering anti-IL-10R monoclonal antibody increased levels of antigen-specific IFN-γ+ or IL-2+ CD4+ T cells, enhanced central and effector memory CD4+ T cell responses, and provided better protection against aerosol infection with 300 CFUs of M.tb.ConclusionOur findings are crucial for formulating effective immunization strategies related to the BCG vaccine and for developing efficacious adult TB vaccines.Graphical abstract

Comparison of a SARS-CoV-2 mRNA booster immunization containing additional antigens to a spike-based mRNA vaccine against Omicron BA.5 infection in hACE2 mice.

The emergence of SARS-CoV-2 variants presents challenges to vaccine effectiveness, underlining the necessity for next-generation vaccines with multiple antigens beyond the spike protein. Here, we investigated a multiantigenic booster containing spike and a chimeric construct composed of nucleoprotein (N) and membrane (M) proteins, comparing its efficacy to a spike-only booster against Omicron BA.5 in K18-hACE2 mice. Initially, mice were primed and boosted with Beta (B.1.351) spike-only mRNA, showing strong spike-specific T cell responses and neutralizing antibodies, albeit with limited cross-neutralization to Omicron variants. Subsequently, a spike-NM multiantigenic vaccine was then examined as a second booster dose for protection in hACE2-transgenic mice. Mice receiving either homologous spike-only or heterologous spike-NM booster had nearly complete inhibition of infectious virus shedding in oral swabs and reduced viral burdens in both lung and nasal tissues following BA.5 challenge. Examination of lung pathology further revealed that both spike-only and spike-NM boosters provided comparable protection against inflammatory infiltrates and fibrosis. Moreover, the spike-NM booster demonstrated neutralization efficacy in a pseudovirus assay against Wuhan-Hu-1, Beta, and Omicron variants akin to the spike-only booster. These findings indicate that supplementing spike with additional SARS-CoV-2 targets in a booster immunization confers equivalent immunity and protection against Omicron BA.5. This work highlights a promising strategy for individuals previously vaccinated with spike-only vaccines, potentially offering enhanced protection against emerging coronaviruses.

Nutrient Supplements for Young Children and Mothers' Self Medication with Over-the-Counter Drugs During the COVID-19 Pandemic.

The restriction of access to health services during the COVID-19 pandemic has led to an increase in self-medication. This study aims to examine mothers' use of nutrient supplements with over-the-counter (OTC) medications for their children, including instances of self-medication for themselves. The study also explores maternal characteristics associated with this behavior, the specific medications used, and the reasons for use. In this descriptive study, 450 mothers with children aged 2 to 6 years in Türkiye were recruited through social media platforms. Questions focused on whether mothers used supplements for themselves and their children, types of products, frequency, and reasons for use. Multivariable binary logistic regression was conducted to examine the factors associated with OTC medication use for children. Nearly half of the mothers reported administering OTC medications to their children. Factors associated with this practice included the child's age (specifically 48-72 months), attendance at nursery, perceived underweight status, and regular health visits with a pediatrician. Additionally, mothers who frequently used medications without a doctor's recommendation were 5.8 times more likely to give OTC drugs to their children. Maternal self-medication was significantly associated with an increased likelihood of OTC medication use for children (OR = 12.1). The most commonly used supplements included vitamin D, fish oil, multivitamins, vitamin C, immune boosters, zinc, probiotics, herbal teas, oral/nasal sprays, throat lozenges, and aspirin, with the primary purposes being prevention and treatment. The administration of OTC medications in young children, who rely heavily on maternal care should be more closely monitored to ensure their safety and well-being, especially during epidemics.

Maintenance of Long-Term Effective Humoral Immune Response in Patients with COVID-19 with Homologous or Heterologous Booster Vaccines: A Retrospective Study.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and first identified in Wuhan, China, in December 2019, has led to global efforts in vaccination to mitigate rising morbidity and mortality, with vaccines proving crucial in controlling the pandemic. This study evaluated the humoral responses to the inactivated virus vaccine Sinopharm or Koxing Kerlafor, the protein subunit vaccine ZF001, and the adenoviral vector vaccine Convidecia after 18 months of inactivated virus vaccination by heterologous and homologous booster vaccination in patients with previous SARS-CoV-2 infection and healthy individuals. We discovered that patients who had recovered from the infection and then received a third vaccine dose (booster) exhibited durable immunity. Furthermore, the heterologous booster vaccine induced higher neutralizing antibody responses compared with the homologous booster. These findings offer valuable insights into the efficacy of different COVID-19 vaccine strategies following booster immunization.

Construction and evaluation of glycoprotein-based nucleic acid vaccines for Marburg virus.

Marburg virus (MARV) is a zoonotic virus that can infect humans and non-human primates (NHPs) and lead to a fatal Marburg hemorrhagic fever (MHF), while there is no approved vaccine or antiviral treatment for MHF. The nucleic acid vaccine has unique advantages, including fast and simple preparation, easy to follow the virus mutation situation, and less adverse reactions. Therefore, we constructed the DNA and mRNA candidate vaccines based on codon-optimized MARV glycoprotein sequence, and evaluated the immune effect in mice through ELISA, ELISpot, and Flow cytometry. After the second booster immunization, both of the candidate vaccines induced strong humoral immune response, enhanced T cell response, and elicited neutralizing antibodies. Notably, DNA candidate vaccine induced stronger humoral immune response, while mRNA candidate vaccine elicited higher levels of IFN-γ and IL-4. In addition, transcriptome analysis revealed that the candidate vaccines activated immune response related pathways. Our study shed new light on the nucleic acid vaccines for MARV and further confirmed the potential of nucleic acid vaccine for future MHF prevention and control.

Live Attenuated aTJ Vaccine Effectively Protects Pigeons Against Homologous PPMV-1 Challenge.

Background: Pigeon paramyxovirus type 1 (PPMV-1) is a significant pathogen affecting pigeon populations globally. The commonly used La Sota vaccine provides limited protection due to antigenic divergence from circulating PPMV-1 strains. An antigenically matched vaccine is needed to address this challenge. Methods: An attenuated aTJ strain was developed through reverse genetics by modifying the F protein cleavage site of the virulent TJ-WT strain. Pigeons were immunized twice with the aTJ strain via eyedrop and intranasal routes, followed by a challenge with a virulent PPMV-1 strain ten days after the booster immunization. Results: The attenuated aTJ strain induced robust serum antibody titers post-booster immunization, and vaccinated pigeons showed strong protection upon challenge, with significantly reduced morbidity, mortality, and viral shedding compared to controls. Conclusions: These findings suggest that the aTJ strain is a promising candidate for the promotion of PPMV-1 prevention and control, emphasizing the importance of antigenic matching in optimizing vaccine efficacy.