Search Results (2,449)

Macrophages are highly plastic innate immune cells that adopt context-dependent phenotypes along a continuum, integrating developmental origin with local microenvironmental cues rather than conforming to discrete M1/M2 states. This review delineates the molecular circuits shaping macrophage identity—TLR/cytokine signaling, microRNA networks, metabolic rewiring, and epigenetic mechanisms including histone lactylation—and traces how circulating monocyte subsets contribute to tissue macrophage diversity. We examine macrophage plasticity across a broad disease spectrum—oncology, autoimmune and rheumatic diseases, inflammatory bowel disease, infectious diseases, metabolic disorders, and neurological conditions—showing that the pathogenic phenotype is strikingly context-dependent: for instance, M2-like tumor-associated macrophages promote immune evasion in solid tumors, whereas M1-skewed programs drive tissue damage in autoimmunity. Soluble markers (sCD163, sCD14, soluble mannose receptor) are emerging biomarkers of disease activity and prognosis. High-dimensional flow cytometry and mass cytometry (CyTOF) bridge molecular biology and clinical phenotyping, enabling integrated readouts of surface phenotype, intracellular signaling, and metabolic state. Therapeutic strategies discussed include selective tumor-associated macrophage (TAM) reprogramming, chimeric antigen receptor (CAR)-M cell therapies, and biomaterial-based platforms. Future priorities encompass spatially resolved multi-omics, epigenetic and metabolic targeting, and macrophage-centered vaccine approaches. Standardized cytometry panels will be essential for biomarker-guided stratification and context-specific interventions. Full article

Background/Objectives: Tuberculosis, caused by Mycobacterium tuberculosis, remains a major global health challenge requiring novel prevention strategies. This study aims to developed an immunoinformatics-guided framework coupled with experimental screening to prioritize for multi-epitope mRNA vaccine design. Methods: Eight immunologically relevant antigens were computationally analyzed to predict cytotoxic (CTL) epitopes and helper T lymphocyte (HTL) epitopes. Population coverage, immune simulation, molecular docking, and normal mode analysis (NMA) were performed in silico. To evaluate peptide immunoreactivity, human IFN-γELISPOT assays were conducted using the candidate peptides, though HLA restriction was not experimentally validated. Results: The workflow identified 14 candidate CTL and 8 HTL epitopes, yielding an estimated global population coverage of 82.6% (60.7% in China; 51.2% in Indonesia). Immune simulations predicted robust humoral and Th1-associated cellular responses, though sustained CD8⁺ memory responses appeared limited. Docking and NMA suggested favorable structural interactions with TLR3 and TLR4. Crucially, the IFN-γ ELISPOT assay validated eight reactive epitopes that partially coincided with computational predictions within the tested donor group. Conclusions: This study establishes an integrated computational–experimental workflow for T cell epitope prioritization. The identified reactive epitopes provide a preliminary immunological basis and candidate pool for the future design and evaluation of multi-epitope mRNA vaccine strategies against tuberculosis. Full article

Background: mRNA vaccines, first approved in December 2020, have been used globally to prevent infectious diseases, and those for treating cancers are being developed. Safety-related labelling changes of Comirnaty and Spikevax were made in June 2025; however, concerns remain. This study assessed the potential risks associated with mRNA vaccines on the indications previously approved, utilizing Real-World Data (RWD) of Adverse Events Following Immunization (AEFIs) derived from the Vaccine Adverse Event Reporting System (VAERS) and Academic Literature Databases (ALD). Methods: A Disproportionality Analysis (DPA) was performed using the Reporting Odds Ratio (ROR) and the Bayesian Confidence Propagation Neural Network (BCPNN) algorithm on spontaneous case reports from VAERS. Statistical positive signals were cross-validated with literature case reports from ALD to provide more comprehensive medical descriptions and clearer causal assessments, and compared with safety information documented in clinical trials and on vaccine labelling. Time-to-onset, stratified, and immunization schedule analyses were conducted to characterize the safety profiles of mRNA vaccines. Results: In total, 5,040,725 spontaneous case reports and 4,387 literature case reports were analyzed. In both VAERS and ALD, new signals involving blood and lymphatic system disorders (e.g., thrombotic thrombocytopenic purpura) and ear and labyrinth disorders (e.g., deafness) were detected from Comirnaty as Designated Medical Events (DMEs), while blood and lymphatic system disorders (e.g., thrombotic thrombocytopenic purpura) from Spikevax in ALD only. No new signals were detected from other vaccines on the DMEs list. In VAERS, Serious Adverse Events (SAEs) were more common in females, while death risk was higher in males. In ALD, SAEs were more common in males for most mRNA vaccines, except Comirnaty. Medical history emerged as a key risk factor for SAEs, particularly among older adults. Conclusions: Statistically significant safety signals were detected across all mRNA vaccines based on five-year cumulative RWD, indicating the need of intensified monitoring of specific populations, including older adults and individuals with medical histories, alongside further optimization of vaccination strategies. Full article

Background/Objectives: In the first months of their life, infants rely on maternal antibodies for immune protection. Breastmilk is a major source of these defenses, supplying secretory IgA, IgG, and IgM that help guard mucosal surfaces against pathogens such as SARS-CoV-2. Most studies on breastmilk immunity in the context of COVID-19 have emphasized circulating monomeric IgA, rather than the multimeric secretory IgA (sIgA) that is active at mucosal barriers. This study assessed in-depth the contribution of breastmilk antibody subtypes to SARS-CoV-2 neutralization capacity and how these profiles differ following maternal COVID-19 infection versus vaccination during pregnancy or postpartum. Methods: In this prospective cohort study, breastmilk samples were collected longitudinally from individuals who had COVID-19 during pregnancy or received COVID-19 mRNA vaccination during pregnancy or postpartum. Serological assays measured IgG, IgM, systemic IgA, and secretory IgA against SARS-CoV-2 spike and nucleocapsid antigens. Results: COVID-19 infection during pregnancy resulted in significantly higher systemic and secretory IgA levels compared to vaccination. Secretory IgA demonstrated a strong correlation with neutralization capacity. Principal component analysis revealed distinct antibody profiles in COVID-19-exposed individuals versus vaccinated cohorts, with significant overlap between pregnancy and postpartum vaccination groups. Conclusions: Although both COVID-19 vaccination and disease elicit sustained COVID-19-related antibodies in breastmilk, COVID-19 infection elicits a broader and more diverse antibody response in breastmilk, specifically with a greater secretory IgA generation. These findings support the value of maternal vaccination to safely confer mucosal immunity to neonates and the need for optimized vaccine formulations for mucosal immunity. Full article

Background: Conventional drug delivery systems often lead to fluctuating plasma concentrations (“Peak and Trough” phenomenon), causing toxicity or inefficacy. Microfluidics has emerged as a revolutionary tool to overcome, among other applications, the limitations of conventional bulk encapsulation methods, such as polydispersity and poor reproducibility. Methods: A systematic review of the literature published between 2020 and 2025 was conducted to evaluate the application of microfluidics in the synthesis of advanced nanomedicines. The review focused on Lipid Nanoparticles (LNPs), Polymeric Nanoparticles (PNPs), and Hydrogel Microspheres. Results: Microfluidics enables the production of monodisperse particles with precise control over geometry and drug loading stoichiometry. Key therapeutic applications include oncology (passive and active targeting), gene therapy (mRNA vaccines), and regenerative medicine (diabetic wound healing). Conclusions: While microfluidics offers superior quality control compared to bulk methods, industrial scalability remains the primary challenge, currently addressed through parallelization and continuous flow strategies. Full article

The global expansion of highly pathogenic avian influenza A (H5N1), particularly the clade 2.3.4.4b lineage, has renewed urgent concerns about its pandemic potential in the context of its ongoing panzootic expansion and increasing cross-species transmission. Despite decades of preparedness initiatives, critical technological and structural gaps persist, especially in low- and middle-income countries (LMICs), where both vaccine access and sustainable manufacturing capacity remain limited. In this perspective, we examine key lessons from past influenza pandemics and global preparedness strategies, including the Global Action Plan for Influenza Vaccines, highlighting persistent challenges related to sustainable manufacturing capacity and equitable vaccine access. Additionally, we examine the potential of messenger RNA (mRNA) vaccine platforms to address these limitations, given their rapid design, scalable manufacturing, and adaptability to emerging pathogens. Moreover, we examine the role of neuraminidase (NA) as a complementary antigen capable of broadening immune protection and reducing viral transmission. Finally, we describe recent advances in Latin America, focusing on Argentina’s participation in the mRNA Technology Transfer Programme co-led by the World Health Organization (WHO) and the Medicines Patent Pool (MPP), as a model for strengthening regional manufacturing capacity and contributing to global pandemic preparedness. Together, these elements indicate that effective H5N1 pandemic preparedness will require the integration of improved antigen design, flexible mRNA platforms, and sustainable regional manufacturing systems aligned with global procurement strategies. Full article

Background: Adenovirus-vectored vaccines played an important role in the global response to SARS-CoV-2. Adenovirus platforms have many advantages including a simple and readily transferred manufacturing process, low cost, and thermostability. Speed of production of an initial Good Manufacturing Practice (GMP)-compliant batch has, however, been viewed as a limitation of adenovirus vectors relative to mRNA platforms. Production of the initial viral starting material and release testing are key rate-limiting steps. Methods: Production of viral starting material from DNA, and release testing in accordance with regulatory expectations, for first-in-human trials of adenovirus-vectored vaccines. Results: We describe experience of these stages in the production of the first GMP batches for multiple adenovirus-vectored candidates and the adaptations made for ChAdOx1 nCoV-19 (the Oxford COVID-19 vaccine) in early 2020. We also report development of a streamlined approach to starting material generation, enabling initial GMP batch availability within c. 60 days of publication of a new pathogen sequence. Using a New World arenavirus vaccine construct as a proof of concept, we demonstrate reproducible execution of this pipeline, maintaining acceptable infectivity and other quality attributes. Conclusions: We discuss opportunities for additional time savings in the future. This work demonstrates suitability of an adenovirus platform to contribute to the “100 Days Mission” for vaccines against “Disease X”. Full article

Pancreatic ductal adenocarcinoma (PDAC) is the most complex and aggressive disease with the worst rates of unresectable or metastatic disease at diagnosis, resistance to systemic therapy, and case fatality rate (CFR) among leading cancers. In non-metastatic disease, neoadjuvant treatment with modern chemotherapeutic regimens followed by surgical resection and/or adjuvant mFOLFIRINOX has significantly improved oncological outcomes. However, recurrence rates remain alarmingly high, while immune checkpoint inhibitors (ICIs) or molecularly targeted therapy have not yet demonstrated clinical benefits. Comprehensive genomic profiling through NGS-based approved assays such as TruSight Oncology 500 (TSO500) could guide targeted therapy. Rapidly evolving mRNA cancer vaccines and circulating tumor DNA (ctDNA)-based prediction of minimal residual disease (MRD) and recurrence risk hold great promise towards the realization of rational combination therapy to improve recurrence-free survival (RFS) and overall survival (OS). More recently, single-cell multiomics (SC MO), spatial proteomics and transcriptomics (SPT), artificial intelligence (AI), and systems biology have revolutionized cancer research, enabling holistic tumor microenvironment (TME) analysis. In this comprehensive review, we describe the latest advances and unmet needs in the standard of care of PDAC. Moreover, we discuss the expectations of ongoing randomized clinical trials of adjuvant mRNA vaccine-based therapy and ctDNA MRD testing as prognostic biomarkers, towards personalized treatment to improve RFS and OS in a medium-term perspective. With a longer perspective, we explore how harnessing SC MO, SPT, AI, and systems biology can reveal the 3D spatial organization of interacting cancer, immune, and stromal cells. Multi-dimensional TME-, TSO500- and ctDNA-based framework of dynamic biomarkers are of paramount importance to achieve an optimal patient-specific perioperative multimodal treatment combining precision immunotherapy, targeted drugs, and modern chemotherapy, translated into future practice-changing clinical trials, that could eliminate MRD towards recurrence prevention. Full article

Porcine enteric coronaviruses (PECs), including porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine deltacoronavirus (PDCoV), and swine acute diarrhea syndrome coronavirus (SADS-CoV), remain major causes of neonatal diarrhea, dehydration, mortality, and economic loss in swine production. Despite substantial progress in vaccine development, durable field protection is still inconsistent. In this narrative review, this narrative review synthesizes current knowledge on PEC vaccine design from three connected perspectives: antigenic breadth, mucosal immunity, and translational evaluation. The economic and virological context of PEC vaccine development is first summarized, including the recurrent production burden of PECs, coronavirus genome organization, structural proteins, and the central role of the spike protein in receptor engagement, membrane fusion, and neutralizing antibody induction. Key issues are then discussed, including how spike diversity, conformational stability, epitope accessibility, glycan shielding, and antigen matching influence protective breadth; why intestinal secretory IgA, mucosal immune-cell trafficking, local memory responses, and lactogenic immunity should be prioritized as biologically relevant endpoints; and how delivery route, adjuvant selection, and platform design shape response quality. Current evidence on recombinant protein, viral-vectored, nanoparticle, virus-like particle, probiotic, plant-derived, and mRNA-based approaches is compared with attention to both promise and current evidentiary and translational limitations. The available literature suggests that future progress in PEC vaccinology is likely to depend less on platform novelty alone than on integrated vaccine designs that align antigen selection, mucosal delivery, maternal–neonatal protection, heterologous challenge, manufacturability, and field applicability. Full article

The role of adjuvant therapy in stage III melanoma is well established in clinical practice. Because stage IIB–IIC melanoma carries a risk of recurrence and melanoma-specific mortality comparable to that of stage III disease, adjuvant approaches have also been developed for patients with thick stage II tumors. Both pembrolizumab and nivolumab have demonstrated efficacy in reducing the risk of local and distant recurrence in patients with high-risk stage II melanoma, whereas evidence supporting the use of BRAF-MEK inhibitors in this setting remains inconclusive. Combinations of immune checkpoint inhibitors, as well as immunotherapy combined with mRNA-based vaccines, are currently under investigation in clinical trials. However, given the non-trivial risk of immune-related adverse events, careful selection of patients with stage II disease who are most likely to derive meaningful benefit from adjuvant therapy is essential. In this context, several clinicopathologic variables and gene expression profiling-based prognostic tools have been proposed to refine risk stratification. To date, however, none of these instruments have been incorporated into routine clinical practice, and no validated predictive biomarkers are available. Accordingly, optimal patient selection for adjuvant therapy remains an important unmet clinical need in early-stage melanoma. Full article

Local pulmonary delivery offers a non-invasive application route for mRNA therapeutics with the potential for high bioavailability at the target-site of applications such as mucosal vaccination or the treatment of lung diseases. However, efficient delivery remains challenging due to major lung-specific barriers, particularly mucus. Herein, pH-responsive, amphiphilic xenopeptides comprising lipoamino fatty acids and oligoamino acids (OAAs) connected in distinct branched U-shape or bundle topologies were evaluated as mRNA polyplexes for delivery to A549 and Calu-3 lung cells under standard submerged or air–liquid interface (ALI) transfection conditions, and upon intratracheal application in BALB/c mice. Optionally, polyplexes were coated with negatively charged hyaluronic acid (HA) or colloidally stabilized with poly(ethylene glycol) (PEG). For U-shapes, hydrophobic modification of the OAA domain boosted their efficiency. Interestingly, best-performing formulations varied across transfection conditions. While the bundle topology showed the highest potential in submerged cell culture, U-shaped carriers were more efficient under ALI conditions. Polyplex surface modification with HA or PEG did not strongly alter in vitro transfections, whereas hydrophobized U-shape core polyplexes combined with surface modification enhanced their efficiency in vivo. Thus, the cationizable core and surface properties of mRNA nanoparticles require specific balancing in various lung cell models and lung. Full article

Messenger RNA (mRNA) therapeutics are redefining treatment approaches in vaccines, cancer immunotherapy, protein replacement, and gene editing. Lipid nanoparticles have enabled early clinical successes, but they can be limited by liver-dominant biodistribution, long-term storage stability, and systemic tolerability. Polymeric delivery systems offer a versatile alternative, with tunable physicochemical properties enabling precise control over mRNA complexation, protection, release, and targeting. This review examines recent progress across polyethyleneimine derivatives, poly(β-amino ester)s, poly(amino acid)s, polyesters, dendrimers, charge-altering releasable transporters, and lipid-polymer hybrids. We highlight strategies such as structural modification, stimuli-responsive designs, and high-throughput polymer screening that enhance stability, reduce cytotoxicity, and enable organ- or cell-specific delivery. Addressing challenges in immunogenicity, biodistribution, and manufacturing scalability will be pivotal to translating these innovations into safe and effective mRNA therapeutics. Full article

The hepatitis B (HBV), C (HCV), and D (HDV) viruses remain a major public health burden. Occult HBV infection (OBI) represents a hidden reservoir with clinical and epidemiological significance, yet its prevalence in Northwest Russia is unknown. We aimed to comprehensively assess the serological and molecular epidemiology of HBV, HCV, and HDV in St. Petersburg and the Leningrad region. Methods. In this cross-sectional study, 6773 apparently healthy volunteers were enrolled. Plasma samples were tested for hepatitis B surface antigen (HBsAg), antibodies to HBV core antigen (anti-HBc), antibodies to HBsAg (anti-HBs), antibodies to HCV (anti-HCV), and antibodies to HDV (anti-HDV) by ELISA. All anti-HCV- and anti-HDV-positive samples were tested for HCV RNA and HDV RNA by real-time PCR. All samples were tested for HBV DNA using a highly sensitive in-house nested real-time PCR assay (detection limit: 5 IU/mL). All “HBV DNA-positive, HBsAg-negative” cases confirmed by two independent extractions were classified as OBI. Vaccination status, self-reported history, and iatrogenic interventions were recorded. Results. Overall seroprevalence values were: HBsAg 1.7%; anti-HBc 11.3%; anti-HBs 43.0%; anti-HCV 1.9%; and anti-HDV 0.6%. Anti-HBc increased sharply with age (3.1% in children to 26.4% in the elderly, p < 0.0001), while anti-HBs declined (69.9% to 29.8%, p < 0.0001). HBV DNA was detected in 118 participants (1.7%). Of these, only 73 individuals (1.1%) were HBsAg-positive, while the remaining 45 participants (0.7%) had undetectable HBsAg, meeting the criteria for OBI. OBI was detected across all age groups, including children. Serological profiling of OBI cases revealed that 57.8% lacked both anti-HBc and anti-HBs, 35.6% had isolated anti-HBs, 2.2% had isolated anti-HBc, and 4.4% had both antibodies. HCV RNA was detected in 15.0% of anti-HCV-positive individuals (all adults). No HDV RNA was detected. Self-reported history underestimated true infection rates: 1.4% of those denying HBV infection were HBsAg-positive and 10.6% were anti-HBc-positive. Among those denying HCV infection, 1.4% were anti-HCV-positive. Vaccination coverage was 70.8%, declining from 90.9% in children to 39.0% in the elderly (p < 0.0001). Among vaccinated individuals, 48.0% lacked protective anti-HBs (<10.0 mIU/mL). Conclusions. This comprehensive serological and molecular study in Northwest Russia is the first to combine population-level serology with molecular detection of HBV, HCV, and HDV, including OBI in this region, and reveals that OBI accounts for a substantial proportion (38%) of all active HBV infections and is strongly associated with a history of iatrogenic interventions. The presence of OBI across all age groups, including children, shows that HBsAg screening alone substantially underestimates the true HBV burden. High rates of unrecognized infection and waning vaccine-induced immunity, highlight critical gaps in current surveillance. These findings provide an evidence-based rationale for integrating molecular testing into screening algorithms and for considering booster vaccination strategies to achieve viral hepatitis elimination goals. Full article

Background/Objectives: Respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and parainfluenza virus type 3 (PIV3) are leading causes of acute respiratory infections in children and the elderly, yet no licensed T-cell vaccines are available. This study aimed to develop multivalent T-cell vaccine candidates against these pathogens using a live attenuated influenza virus (LAIV) vector platform. Methods: Conserved F, N, and M proteins of RSV, hMPV, and PIV3 were identified through multiple sequence alignments. Fragments enriched with experimentally confirmed and predicted T-cell epitopes were selected using the IEDB and NetMHCpan servers. These fragments were assembled into polyepitope immunogenic cassettes, and their selected order was determined by thermodynamic analysis of mRNA secondary structures using the RNAfold Web Server. The selected cassettes were cloned into the neuraminidase (NA) gene of a cold-adapted LAIV vector. Recombinant viruses were rescued by reverse genetics and assessed for replicative fitness in embryonated chicken eggs and MDCK cells, NA enzymatic activity and genetic stability upon serial passaging. Results: Four cassettes were designed for RSV, three for hMPV, and one for PIV3, all containing fragments with multiple T-cell epitopes. Three recombinant viruses of LAIV/RSV type and three of LAIV/hMPV type were successfully rescued, while attempts to recover the remaining recombinant viruses, i.e., LAIV/RSV and LAIV/PIV3, were not successful. All rescued recombinant viruses replicated to titers comparable to the parental LAIV strain and retained the full-length insert for at least eight passages in eggs. Importantly, NA enzymatic activity of the LAIV vector was not compromised by the insertion of the polyepitope T-cell cassettes. Conclusions: We developed a panel of recombinant T cell-based vaccine candidates against RSV and hMPV using the LAIV vector platform. These recombinant viruses encode conserved T-cell epitopes of the target viruses while retaining the biological properties of LAIV strains. Taken together, these characteristics warrant further evaluation of these recombinant viruses in appropriate relevant in vitro models to directly assess their immunogenicity in terms of stimulating a T-cell response against target pathogens. Full article

Porcine circovirus type 3 (PCV3) capsid protein (Cap) is a key antigen for immunological studies and vaccine development. Different optimized PCV3 ORF2 sequences were used to construct six baculovirus transfer plasmids, with the pOET1.1-based design yielding the highest Cap level. Cap expression was confirmed by Western blot, IPMA and IFA. Recombinant baculovirus amplification was optimized, achieving the highest titer at an MOI of 0.1 with a 72 h harvest to 10^7.5TCID₅₀/0.1 mL, while maximal Cap production was obtained at an MOI of 0.1 with a 96 h harvest. PCV3 Cap virus-like particles (VLPs) were purified by sucrose density-gradient ultracentrifugation and cation-exchange chromatography, and TEM revealed spherical particles of approximately 17–20 nm. In mice, VLP immunization induced increasing antigen-specific IgG from day 14. Immunization increased both IgG1 and IgG2a without a significant difference, and post-immunization serum specifically recognized PCV3-positive passaged PK-15 cells in an indirect immunofluorescence assay. In splenic lymphocytes, IFN-γ, TNF-α, IL-4, and IL-10 mRNA levels were significantly upregulated (p < 0.01). Moreover, pig challenge data supported the protective potential of PCV3 Cap VLPs in the natural host. In our study, Cap assembled into VLPs and induced immune responses, providing a basis for PCV3 subunit vaccine development. Full article