Search Results (328)

Background/Objectives: Classical swine fever (CSF) continues to challenge global eradication efforts, particularly in endemic regions, where pregnant sows face heightened risks of vertical transmission following exposure to CSFV. Methods: This study evaluates the early protective efficacy of FlagT4G, a novel live attenuated DIVA-compatible vaccine. Pregnant sows were vaccinated at mid-gestation and challenged 14 days later with a highly virulent CSFV strain. Results: FlagT4G conferred complete clinical protection, preventing both maternal viremia and transplacental transmission. No CSFV RNA, specific antibodies, or IFN-α were detected in fetal samples from vaccinated animals. In contrast, unvaccinated sows exhibited clinical signs, high viral loads, and widespread fetal infection. Interestingly, early protection was observed even in the absence of strong humoral responses in some vaccinated sows, suggesting a potential role for innate or T-cell-mediated immunity in conferring rapid protection. Conclusions: The demonstrated efficacy of FlagT4G within two weeks of vaccination underscores its feasibility for integration into emergency vaccination programs. Its DIVA compatibility and ability to induce early fetal protection against highly virulent CSFV strains position it as a promising tool for CSF control and eradication strategies. Full article

Background: Understanding the duration and quality of immune memory following SARS-CoV-2 infection and vaccination is critical for informing public health strategies and vaccine development. While waning antibody levels have raised concerns about long-term protection, the persistence of memory B cells (MBCs) and T cells plays a vital role in sustaining immunity. Materials and Methods: We conducted a longitudinal prospective study over 12 months, enrolling 285 participants in total, either after natural infection or vaccination with BNT162b2 or mRNA-1273. Peripheral blood samples were collected at four defined time points (baseline, 1–2 months, 6–7 months, and 12–13 months after vaccination or disease onset). Immune responses were assessed through serological assays quantifying anti-RBD IgG and neutralizing antibodies, B-ELISPOT, and multiparameter flow cytometry for S1-specific memory B cells. Results: Both mRNA vaccines induced robust B cell and antibody responses, exceeding those observed after natural infection. Memory B cell frequencies peaked at 6 months and declined by 12 months, but remained above the baseline. The mRNA-1273 vaccine elicited stronger and more durable humoral and memory B-cell-mediated immunity compared to BNT162b2, likely influenced by its higher mRNA dose and longer prime-boost interval. Class-switched memory B cells and S1-specific B cells were significantly expanded in vaccine recipients. Natural infection induced more heterogeneous immune memory. Conclusions: Both mRNA vaccination and natural SARS-CoV-2 infection induce a comparable expansion of memory B cell subsets, reflecting a consistent pattern of humoral immune responses across all studied groups. These findings highlight the importance of vaccination in generating sustained immunological memory and suggest that the vaccine platform and dosage influence the magnitude and durability of immune responses against SARS-CoV-2. Full article

Vaccine adjuvants are non-immunogenic agents that enhance or modulate immune responses to co-administered antigens and are essential to modern vaccines. Despite their importance, few are approved for human use. The rise of new pathogens and limited efficacy of some existing vaccines underscore the need for more advanced and effective formulations, particularly for vulnerable populations. Aluminum-based adjuvants are commonly used in vaccines and effectively promote humoral immunity. However, they mainly induce a Th2-biased response, making them suboptimal for diseases requiring cell-mediated immunity. In contrast, saponin-based adjuvants from the Quillajaceae family elicit a more balanced Th1/Th2 response and generate antigen-specific cytotoxic T cells (CTL). Due to ecological damage and limited availability caused by overharvesting Quillaja saponaria Molina barks, efforts have intensified to identify alternative plant-derived saponins with enhanced efficacy and lower toxicity. Quillaja brasiliensis (A.St.-Hil. and Tul.) Mart. (syn. Quillaja lancifolia D.Don), a related species native to South America, is considered a promising renewable source of Quillajaceae saponins. In this review, we highlight recent advances in vaccine adjuvant research, with a particular focus on saponins extracted from Q. brasiliensis leaves as a sustainable alternative to Q. saponaria saponins. These saponin fractions are structurally and functionally comparable, exhibiting similar adjuvant activity when they were formulated with different viral antigens. An alternative application involves formulating saponins into nanoparticles known as ISCOMs (immune-stimulating complexes) or ISCOM-matrices. These formulations significantly reduce hemolytic activity while preserving strong immunoadjuvant properties. Therefore, research advances using saponin-based adjuvants (SBA) derived from Q. brasiliensis and their incorporation into new vaccine platforms may represent a viable and sustainable solution for the development of more less reactogenic, safer, and effective vaccines, especially for diseases that require a robust cellular immunity. Full article

Heart failure (HF), a prevalent global health issue characterized by the heart’s impaired ability to pump or fill blood, affects millions worldwide and continues to pose significant challenges despite advancements in treatment. This review delves into the critical and increasingly recognized role of inflammation in the development and progression of this complex syndrome. While the incidence of HF has seen a decline in some regions due to improved cardiac care, its overall prevalence is rising, particularly among younger adults and those with heart failure with a preserved ejection fraction (HFpEF). Given the persistently high rates of hospitalization and mortality associated with HF, understanding the underlying mechanisms, including the contribution of inflammation, is crucial for identifying novel therapeutic strategies. Inflammation in heart failure is a multifaceted process involving the activation of the immune system, both innate and adaptive, and encompasses various mechanisms such as the release of pro-inflammatory mediators, endothelial dysfunction, and neurohormonal activation. Myocardial damage triggers the innate immune response, while humoral immunity and chronic systemic inflammation, often linked to cardiovascular risk factors and autoimmune diseases, also play significant roles. Notably, heart failure and inflammation have a reciprocal relationship, with HF itself contributing to inflammatory processes within the cardiac tissue and systemically. Understanding these intricate pathways, including the involvement of specific immune cells and molecular mediators, is essential for comprehending the pathogenesis of heart failure and exploring potential therapeutic interventions. The review further examines various inflammatory biomarkers that have been implicated in heart failure, such as cytokines (including TNF-α and IL-1) and C-reactive protein (CRP). While these markers often correlate with the severity and prognosis of HF, clinical trials targeting specific inflammatory mediators have largely yielded disappointing results, highlighting the complexity of the inflammatory response in this context. The exploration of these biomarkers and the challenges encountered in translating anti-inflammatory strategies into effective treatments underscore the need for continued research to unravel the precise role of inflammation across different HF subtypes and to develop more targeted and effective anti-inflammatory therapies. Full article

In the current global health environment, the spread of the monkeypox virus (MPXV) and the persistent threat of human immunodeficiency virus (HIV) have become critical public health challenges. Since 2022, MPXV has rapidly disseminated worldwide, and nearly half of MPXV-infected individuals are co-infected with HIV. This complex situation calls for innovative preventive strategies. In this study, an innovative multi-epitope vaccine was designed using bioinformatics and immunoinformatic approaches. Ten HIV proteins and nine MPXV proteins were used to predict potential epitopes. Non-allergenic, highly antigenic, IFN-γ-inducible, and non-toxic epitopes were selected to construct the multi-epitope vaccine. It was found that the designed vaccine construct was highly antigenic, soluble, and had acceptable physicochemical properties. Based on molecular docking and molecular dynamics simulation (MDs) analyses, the vaccine construct demonstrated stable and robust interactions with Toll-like receptors (TLR2, TLR3, and TLR4). Although no actual animal experiments have been conducted to evaluate the vaccine’s effectiveness, immune simulations showed that the vaccine could elicit potent humoral and cell-mediated immune responses. Overall, this study provides a promising vaccine candidate against MPXV and HIV co-infection and emphasizes innovative strategies to interrupt the international transmission of these two viruses. Full article

Fc receptor-like 1 (FcRL1), a co-receptor specifically expressed on the surface of B-cells, plays a pivotal role in modulating B-cell immune activation and orchestrating humoral immune responses. This comprehensive review systematically synthesizes research advances in FcRL1 mediated transmembrane signal transduction mechanisms, its regulatory capacity in humoral immune responses, expression patterns during B-cell differentiation and development, and expression dynamics in B-cell malignancies, while critically evaluating the therapeutic potential of FcRL1 as a cellular targeting candidate. Full article

Diclofenac is an effective medication for pain and inflammation. However, its use has been linked to hepatitis. To gain insight into diclofenac’s ability to cause hepatitis, we investigated the regulation of major effectors of the immune system following daily treatment of minipigs at 3 and 15 mg/kg for 28 days. Histopathology evidenced lobular inflammation, and through a combination of immunogenomics and immunopathology, we detected marked innate and adaptive immune responses. We identified 109 significantly regulated genes linked to neutrophil, monocyte, Kupffer cell, and lymphocyte responses and 32 code for cytokine- and interferon-γ-signaling. In support of wound repair, immunopathology evidenced manifest upregulation of macrophage migration inhibitory factor and CD74. Furthermore, the strong expression of IgG and IgM underscored humoral immune responses. Diclofenac caused an activation of the complement system, especially the C1 inhibitor of the classical pathway and C3 with critical functions in liver regeneration. The marked expression of complement factor B and H of the alternate pathway modulated B-cell responses. Likely, the upregulation of factor H protected hepatocytes from injury by limiting complement-mediated damage of inflamed cells. Additionally, diclofenac treatment elicited marked hepatic expression of lysozyme and KLF6. The latter earmarks M1-polarized Kupffer cells. We observed an extraordinary induction of calprotectin/S100A9 and of the monocyte/macrophage CD163 scavenger receptor, and therefore, we detected innate immune sensing of damaged cells. Lastly, we noted an unprecedented induction of the acute phase reactant SAA1 and DEC-205, which recognize apoptotic and necrotic cells. Together, our results offer mechanistic insights into immune-mediated liver injury patterns following diclofenac treatment. Full article

Coxiella burnetii infection has a worldwide distribution, although the incidence and clinical manifestations vary between and within countries. There are the following four basic forms: asymptomatic infection, acute Q fever, chronic Q fever, and post-Q fever fatigue syndrome. The aim of this review is to provide a comprehensive overview of the important aspects of its pathogenesis and pathophysiology. First, we provide a brief update of the taxonomic aspects, basic structures, and genotypes of C. burnetii necessary for the proper interpretation of the following sections. Routes of infection, different stages of pathogenesis (respiratory entry of C. burnetii; penetration into alveolar macrophages, life cycle, and effects; systemic dissemination), and innate, acquired humoral and cell-mediated immune responses in different forms of infection are described in detail. The pathophysiology and clinical manifestations of Q fever, such as the main mechanisms of injury, in isolation and in combination, are reviewed. The clinical and biological manifestations of the two main forms of Q fever (acute and chronic) are outlined, with a brief definition and mention of the mechanisms of post-Q fever fatigue syndrome. Full article

Background: Lumpy skin disease (LSD) is major transboundary disease affecting cattle and water buffaloes, indirectly causing huge socio-economic losses. Following its first outbreak in India in 2019, the heterologous Goatpox (Uttarkashi strain) vaccine mitigated LSD. Objective: Due to limited data on the spatiotemporal distribution of the disease, this study investigates its dynamics and presents findings from a field study conducted in Maharashtra, India. This study evaluates the safety, immunogenicity, and duration of immunity provided by a heterologous vaccine. Additionally, it examines post-vaccination responses in relation to factors such as age, gender, and breed. Methods: This study employed spatiotemporal analysis of lumpy skin disease (LSD) outbreaks from 2020 to 2024 using GeoDa (v1.22), incorporating Moran’s I and Getis-Ord Gi* statistics to identify spatial clustering patterns. A randomized field trial was conducted to evaluate vaccine safety and immunogenicity in 657 cattle across seven districts. Humoral immune responses were assessed using the serum neutralization test (SNT) and indirect enzyme-linked immunosorbent assay (ELISA), while cell-mediated immunity was evaluated via Interferon-gamma (IFN-γ) ELISA. For sero-monitoring, a total of 1925 serum samples from 22 districts were analyzed. Additionally, statistical analyses (n = 1925), including the Kappa Index, ANOVA, and logistic regression, were performed using SPSS v27 to investigate the influence of factors such as age, sex, and breed (significance level: p < 0.05). Results: LSD exhibited significant spatial clustering across Maharashtra. The Goatpox vaccine was 100% safe, with no adverse reactions. Protective antibody titers (≥1:8) were observed in 96.9% of vaccinated cattle by 14–21 days post-vaccination (dpv), peaking at 60 dpv before declining at 150 dpv. The cell-mediated immune response peaked at 28 dpv. Clinical monitoring for one year showed that only 2% of vaccinated cattle developed mild LSD symptoms after nine months, with no mortality. At six months post-vaccination, seroconversion was 69.7%, with breed significantly influencing seropositivity. Conclusions: This study confirms the Goatpox vaccine’s safety and strong immunogenicity in cattle, marking its first large-scale evaluation in the Indian subcontinent. Further research is needed to assess long-term immunity and protection against virulent LSD strains. Full article

Compounds in sand fly saliva elicit specific immune responses that may play a role in the establishment of canine Leishmania infection. Although canine antibodies to anti-sand fly saliva antigens have been extensively studied, little is known about cellular immune responses against Phlebotomus perniciosus salivary proteins. This study aimed to explore humoral and T-cell-mediated immunity against P. perniciosus salivary proteins in dogs (n = 85) from Mallorca (Spain), a leishmaniosis-endemic area, and find correlations with demographic (age, sex, and breed) and parasite-specific immunological parameters. Anti-sand fly saliva IgG was examined using a P. perniciosus whole salivary gland homogenate (SGH) ELISA and recombinant salivary protein rSP03B ELISA. Interferon gamma (IFN-γ) release whole blood assays with L. infantum soluble antigen (LSA), SGH, and rSP03B were also performed. Positive correlations were found between IgG levels in the SGH and rSP03B tests and between concentrations of SGH IFN-γ and rSP03B IFN-γ. While concentrations of SGH IFN-γ and rSP03B IFN-γ were low and produced only by a minority of dogs (less than 20%), high levels and frequencies of LSA IFN-γ as well as anti-saliva IgG for SGH and rSP03B were detected in a majority of dogs (61% and 75%, respectively). LSA IFN-γ levels were positively correlated with age and Leishmania-specific antibodies. In conclusion, dogs from a leishmaniosis-endemic area presented high humoral immunity against P. perniciosus salivary proteins, but their cellular immunity to these proteins was low and less frequent. Full article

The extensive research and studies conducted over the past decade have greatly improved our comprehension of the pathogenesis and risk factors associated with Spondyloarthritis (SpA). In addition, they have contributed to the advancement of novel therapeutic approaches. Although genetics still represents the primary risk factor for SpA, increasing evidence presented in this review suggests that environmental factors—such as air pollution, smoking, gut microbiota (GM), infections, and diet—also contribute to its pathogenesis. In detail, environmental particulate matters (PMs), which include ligands for the aryl hydrocarbon receptor—a cytosolic transcription factor responsive to toxic substances—facilitate the differentiation of T Helper 17 (Th17) cells, potentially exacerbating the autoinflammatory processes associated with SpA. Furthermore, smoking influences both the cellular and humoral aspects of the immune response, resulting in leukocytosis, impaired leukocyte functionality, and a decrease in various cytokines and soluble receptors, including interleukin (IL) 15, IL-1 receptor antagonist (IL-1Ra), IL-6, soluble IL-6 receptor (sIL-6R), as well as the vascular endothelial growth factor (VEGF) receptor. Studies have indicated that patients with SpA exhibit an increased prevalence of antibodies directed against a conserved epitope shared by the human leukocyte antigen B27 (HLA-B27)- and Klebsiella nitrogenase, in comparison to HLA-B27-positive controls. Additionally, current evidence regarding the GM suggests the presence of a gut–joint–skin axis, wherein the disruption of the mucosal barrier by specific bacterial species may enhance permeability to the gut-associated lymphoid tissue (GALT), resulting in localized inflammation mediated by Th1 and Th17 cells, as well as IL-17A. Finally, this review discusses the role of diet in shaping the microbial composition and its contribution to the pathogenesis of SpA. A comprehensive understanding of the mechanisms by which environmental factors influence the pathogenesis and progression of the disease could facilitate the development of novel personalized therapies targeting both external and internal environmental exposures, such as the gut microbial ecosystem. Full article

Background/Objectives: The combination of a hemagglutinin antigen (HA)-based inactivated influenza vaccine (IIV; Fluarix^® Tetra; GlaxoSmithKline) with a nucleoprotein (NP)-based vaccine, such as OVX836, should increase the efficacy of influenza vaccines since it leverages two complementary immunological mechanisms: HA antibodies targeting the virus envelope and neutralizing it, and an NP cell-mediated immune (CMI) response destroying infected cells. Methods: This was a randomized, double-blind, Phase 2a study (ClinicalTrials.gov NCT05284799) including three groups of 60 healthy subjects (18–55 years old) receiving either IIV + placebo, IIV + OVX836 (480 µg), or OVX836 + placebo intramuscularly and concomitantly into the same deltoid muscle. The endpoints were reactogenicity, safety, and immunogenicity (hemagglutination inhibition assay [HAI], anti-NP immunoglobulin G [IgG], and NP-specific cell-mediated immunity [CMI]). Results: The co-administration of IIV + OVX836 was safe and well-tolerated. The HAI response was strong and similar in the two IIV groups with no interference of OVX836. The humoral anti-NP IgG and NP-specific CMI responses to OVX836 were strong in the two OVX836 groups, and no major interference of IIV was observed. Conclusions: This study supports further clinical development of OVX836 as a combined IIV/OVX836 seasonal vaccine capable of inducing robust and complementary HAI and CMI NP-specific responses. Full article

The activation of immunosuppressed antigen-presenting cells (APCs) in the tumor microenvironment is a key goal in modern cancer immunotherapy. Our laboratory utilizes a liposome-based immunotherapy platform that binds endogenous complement to deliver antigen, adjuvant, and therapeutic agents to APCs in vivo. The liposomes contain external linker groups, which readily bind complement protein C3, and mediate liposomal uptake via complement receptor 3 into APCs. To test the ability of a model antigen to bind to these external linker groups on C3-liposomes and elicit a robust adaptive immune response, we conjugated a modified ovalbumin peptide (OVA-C) to the liposomes and incorporated a toll-like receptor (TLR) 4 agonist, monophosphoryl lipid A (MPLA), in the liposomal membrane. Adaptive immune responses from C57BL/6 mice were analyzed by ELISA and ELISpot. Mice vaccinated with OVA-C liposomes elicited significantly greater humoral and cellular adaptive responses relative to controls. Furthermore, female mice vaccinated with MPLA + OVA-C liposomes produced significantly more IgG antibodies than males vaccinated with the same liposomes. In conclusion, antigen binding on the exterior of C3-liposomes markedly improves antigen loading efficiency and still allows for complement C3-targeted delivery to APCs. These data demonstrate the initiation of a robust cellular and humoral immune response using a new liposomal delivery platform. Full article

The varicella vaccine has prevented varicella in hundreds of thousands of patients since its establishment in 1974. It stimulates both humoral and cell-mediated immunity to produce an immune response that helps protect against the disease (not necessarily the infection). Serious sequala of varicella including pneumonia, hepatitis, and encephalitis can occur, with higher incidence in immunosuppressed individuals than in the general population. Patients who are not immunosuppressed should receive routine varicella vaccinations. For those who have not completed the series or are significantly distant from their last immunization, serologic testing may be considered. In pre-transplant patients, live-attenuated vaccines should ideally be administered at least four weeks before transplantation. Case studies have documented instances of patients requiring treatment for varicella after receiving a transplant within four weeks of vaccination. Full article

Background/Objectives: Chlamydia trachomatis (Ct) is the leading bacterial cause of sexually transmitted infection globally. If undiagnosed or left untreated, these infections can lead to serious complications such as infertility, ectopic pregnancies, and chronic pelvic pain. Despite the high prevalence and potential for serious health complications, no vaccine has been licensed. Pigs offer a valuable biomedical model for chlamydia research: they have an overall high degree of similarity to humans and serve as natural hosts for Chlamydia suis (Cs), a close relative of Ct. Thus, in this study, the pig model was used to evaluate a vaccine candidate against Ct. Methods: The vaccine candidate consists of chlamydial-protease-like activity factor (CPAF) protein adjuvanted with STING (Stimulator of Interferon Genes) pathway agonist cyclic-di-AMP (c-di-AMP). Pigs received two doses intramuscularly followed by two intranasal doses. Each week, the systemic T cell response was assessed via IFN-γ and IL-17 ELISpots, as well as multi-parameter flow cytometry on 0, 14, and 28 days post vaccination (dpv). The humoral immune response was analyzed by measuring CPAF-specific antibody levels and avidity via ELISAs. Results: Vaccination with c-di-AMP adjuvanted CPAF triggered low-level systemic IFN-γ and multifunctional IFN-γ⁺TNF-α⁺ CD4 T cell responses. Despite the rather low systemic effector cytokine production, robust anti-CPAF IgG responses were detected in serum, vaginal swab eluates, and oviduct flushes. Genital Ct challenge 42 dpv resulted in only transient infection, precluding a confident assessment of vaccine efficacy of the tested CPAF/c-di-AMP vaccine candidate. However, after challenge, vaccinated pigs exhibited boosted systemic anti-CPAF IFN-γ and mucosal IgG responses compared to unvaccinated pigs. Conclusions: Thus, while vaccine efficacy remains elusive, the CPAF/c-di-AMP vaccine candidate was immunogenic: it elicited a low-level systemic cell-mediated response and robust humoral immune responses. Future studies will incorporate a STING agonist directly conjugated to CPAF as well as addition of other Th1-inducing adjuvants to enhance cellular immunity. Full article