Cancer is characterized by unlimited proliferation and metastasis, and traditional therapeutic strategies usually result in the acquisition of drug resistance, thus highlighting the need for more personalized treatment. mRNA vaccines transfer the gene sequences of exogenous target antigens into human cells through transcription and translation to stimulate the body to produce specific immune responses against the encoded proteins, so as to enable the body to obtain immune protection against said antigens; this approach may be adopted for personalized cancer therapy. Since the recent coronavirus pandemic, the development of mRNA vaccines has seen substantial progress and widespread adoption. In the present review, the development of mRNA vaccines, their mechanisms of action, factors influencing their function and the current clinical applications of the vaccine are discussed. A focus is placed on the application of mRNA vaccines in cancer, with the aim of highlighting unique advances and the remaining challenges of this novel and promising therapeutic approach.

The effect of COVID-19 booster vaccination on SARS-CoV-2 T-cell mediated immune responses in elderly nursing home residents has not been explored in depth. Thirty-nine elderly nursing home residents (median age, 91 years) were included, all fully vaccinated with mRNA vaccines. The frequency of and the integrated mean fluorescence (iMFI) for peripheral blood SARS-CoV-2-Spike reactive IFN-γ-producing CD4+ or CD8+ T cells before and after the first (Pre-3D and Post-3D) and second (Pre-4D and Post-4D) vaccine booster doses was determined using flow cytometry for an intracellular staining method. 3D increased significantly (p = 0.01) the percentage of participants displaying detectable SARS-CoV-2-T-cell responses compared with pre-3D (97% vs. 74%). The magnitude of the increase was statistically significant for CD8+ T cells (p = 0.007) but not for CD4+ T cells (p = 0.77). A trend towards higher frequencies of peripheral blood SARS-CoV-2-CD8+ T cells was observed post-3D compared with pre-3D (p = 0.06). The percentage of participants with detectable SARS-S-CoV-2 CD4+ T-cell responses decreased post-4D (p = 0.035). Following 4D, a nonsignificant decrease in the frequencies of both T cell subsets was noticed (p = 0.94 for CD8+ T cells and p = 0.06 for CD4+ T cells). iMFI data mirrored that of T-cell frequencies. The kinetics of SARS-CoV-2 CD8+ and CD4+ T cells following receipt of 3D and 4D were comparable across SARS-CoV-2-experienced and -naïve participants and between individuals receiving a homologous or heterologous vaccine booster. 3D increased the percentage of elderly nursing home residents displaying detectable SARS-CoV-2 T-cell responses but had a marginal effect on T-cell frequencies. The impact of 4D on SARS-CoV-2 T-cell responses was negligible; whether this was due to suboptimal priming or rapid waning could not be ascertained.

UNASSIGNED: This study analyzed the safety of coronavirus disease 2019 (COVID-19) bivalent and monovalent booster vaccines, including the frequency of adverse events (AEs) such as myocarditis and pericarditis, in adolescents aged 12 to 17 years in the Republic of Korea. We aimed to share the safety profile of the COVID-19 bivalent vaccine booster doses.
UNASSIGNED: We analyzed the frequencies of AEs reported to the COVID-19 vaccination management system (CVMS) or self-reported through the text message survey (TMS). Diagnostic eligibility and causality with vaccines were compared using odds ratios (ORs) by vaccine type, and incidence rates per 100,000 person-days were calculated for confirmed cases of myocarditis and pericarditis following monovalent and bivalent booster doses.
UNASSIGNED: In the CVMS, the AE reporting rate (per 100,000 doses) was lower after the bivalent booster (66.5) than after the monovalent booster (264.6). Among the AEs reported for both monovalent and bivalent vaccines, 98.2% were non-serious and 1.8% were serious. According to the TMS, both local and systemic AEs were reported less frequently after the bivalent vaccination than after the monovalent vaccination in adolescents aged 12 to 17 years (p<0.001). The incidence rates per 100,000 person-days for confirmed myocarditis/pericarditis following monovalent and bivalent booster doses were 0.03 and 0.05, respectively; this difference was not statistically significant (OR, 1.797; 95% confidence interval, 0.210-15.386).
UNASSIGNED: AEs in 12- to 17-year-olds following the bivalent booster were less frequent than those following the monovalent booster in the Republic of Korea, and no major safety issues were identified. However, the reporting rates for AEs were low.

Pancreatic ductal adenocarcinoma is the most prevalent pancreatic cancer, which is considered a significant global health concern. Chemotherapy and surgery are the mainstays of current pancreatic cancer treatments; however, a few cases are suitable for surgery, and most of the cases will experience recurrent episodes. Compared to DNA or peptide vaccines, mRNA vaccines for pancreatic cancer have more promise because of their delivery, enhanced immune responses, and lower proneness to mutation. We constructed an mRNA vaccine by analyzing S100 family proteins, which are all major activators of receptors for advanced glycation end products. We applied immunoinformatic approaches, including physicochemical properties analysis, structural prediction and validation, molecular docking study, in silico cloning, and immune simulations. The designed mRNA vaccine was estimated to have a molecular weight of 165023.50 Da and was highly soluble (grand average of hydropathicity of -0.440). In the structural assessment, the vaccine seemed to be a well-stable and functioning protein (Z score of -8.94). Also, the docking analysis suggested that the vaccine had a high affinity for TLR-2 and TLR-4 receptors. Additionally, the molecular mechanics with generalized Born and surface area solvation analysis of the \"Vaccine-TLR-2\" (-141.07 kcal/mol) and \"Vaccine-TLR-4\" (-271.72 kcal/mol) complexes also suggests a strong binding affinity for the receptors. Codon optimization also provided a high expression level with a GC content of 47.04% and a codon adaptation index score 1.0. The appearance of memory B-cells and T-cells was also observed over a while, with an increased level of helper T-cells and immunoglobulins (IgM and IgG). Moreover, the minimum free energy of the mRNA vaccine was predicted at -1760.00 kcal/mol, indicating the stability of the vaccine following its entry, transcription, and expression. This hypothetical vaccine offers a groundbreaking tool for future research and therapeutic development of pancreatic cancer.

Pediatricians and primary care providers serve an important role in building trust with families and communities. To support the critical role of front-line providers, this perspective seeks to reflect on the work of the Centers for Disease Control and Prevention\'s (CDC) Advisory Committee on Immunization Practices to support COVID-19 pandemic response efforts. Although ACIP recommends vaccines for all age groups, this perspective focuses on the pediatric lens and is tailored to Academic Pediatrics. ACIP adapted from in-person meetings 3 times yearly to virtual meetings on an emergency basis to ensure a thorough review and presentation of all the components of Evidence to Recommendation framework, including explicit consideration of equity in the decision-making process. The need for diverse enrollment in clinical trials was highlighted as critical for supporting recommendations and enhancing trust. Near real-time vaccine safety surveillance was implemented at scale and emphasized the importance of collaboration between federal partners engaged in vaccine safety in the U.S. and extended to other countries with similar safety surveillance systems to enable early recognition and response to safety concerns. A key equity opportunity for future pandemics is to shorten the time between vaccine was available for adults and young children.

Adenocarcinoma of the pancreas (PAAD) is one of the deadliest malignant tumors, and messenger ribonucleic acid vaccines, which constitute the latest generation of vaccine technology, are expected to lead to new ideas for the treatment of pancreatic cancer. The Cancer Genome Atlas-PAAD and Genotype-Tissue Expression data were merged and analyzed. Weighted gene coexpression network analysis was used to identify gene modules associated with tumor mutational burden among the genes related to both immunity and oxidative stress. Differentially expressed immune-related oxidative stress genes were screened via univariate Cox regression analysis, and these genes were analyzed via nonnegative matrix factorization. After immune infiltration analysis, least absolute shrinkage and selection operator regression combined with Cox regression was used to construct the model, and the usefulness of the model was predicted based on the receiver operating characteristic curve and decision curve analysis curves after model construction. Finally, metabolic pathway enrichment was analyzed using gene set enrichment analysis combined with Kyoto Encyclopedia of Genes and Genomes and gene ontology biological process analyses. This model consisting of the ERAP2, mesenchymal-epithelial transition factor (MET), CXCL9, and angiotensinogen (AGT) genes can be used to help predict the prognosis of pancreatic cancer patients more accurately than existing models. ERAP2 is involved in immune activation and is important in cancer immune evasion. MET binds to hepatocyte growth factor, leading to the dimerization and phosphorylation of c-MET. This activates various signaling pathways, including MAPK and PI3K, to regulate the proliferation, invasion, and migration of cancer cells. CXCL9 overexpression is associated with a poor patient prognosis and reduces the number of CD8 + cytotoxic T lymphocytes in the PAAD tumor microenvironment. AGT is cleaved by the renin enzyme to produce angiotensin 1, and AGT-converting enzyme cleaves angiotensin 1 to produce angiotensin 2. Exposure to AGT-converting enzyme inhibitors after pancreatic cancer diagnosis is associated with improved survival. The 4 genes identified in the present study - ERAP2, MET, CXCL9, and AGT - are expected to serve as targets for messenger ribonucleic acid vaccine development and need to be further investigated in depth.

Prostate cancer (PCa) is characterized as a \"cold tumor\" with limited immune responses, rendering the tumor resistant to immune checkpoint inhibitors (ICI). Therapeutic messenger RNA (mRNA) vaccines have emerged as a promising strategy to overcome this challenge by enhancing immune reactivity and significantly boosting anti-tumor efficacy. In our study, we synthesized Tetra, an mRNA vaccine mixed with multiple tumor-associated antigens, and ImmunER, an immune-enhancing adjuvant, aiming to induce potent anti-tumor immunity. ImmunER exhibited the capacity to promote dendritic cells (DCs) maturation, enhance DCs migration, and improve antigen presentation at both cellular and animal levels. Moreover, Tetra, in combination with ImmunER, induced a transformation of bone marrow-derived dendritic cells (BMDCs) to cDC1-CCL22 and up-regulated the JAK-STAT1 pathway, promoting the release of IL-12, TNF-α, and other cytokines. This cascade led to enhanced proliferation and activation of T cells, resulting in effective killing of tumor cells. In vivo experiments further revealed that Tetra + ImmunER increased CD8+T cell infiltration and activation in RM-1-PSMA tumor tissues. In summary, our findings underscore the promising potential of the integrated Tetra and ImmunER mRNA-LNP therapy for robust anti-tumor immunity in PCa.

The One Health approach, which integrates the health of humans, animals, plants, and ecosystems at various levels, is crucial for addressing interconnected health threats. This is complemented by the advent of mRNA vaccines, which have revolutionized disease prevention. They offer broad-spectrum effectiveness and can be rapidly customized to target specific pathogens. Their utility extends beyond human medicine, showing potential in veterinary practices to control diseases and reduce the risk of zoonotic transmissions. This review place mRNA vaccines and One Health in the context of tick-borne diseases. The potential of these vaccines to confer cross-species immunity is significant, potentially disrupting zoonotic disease transmission cycles and protecting the health of both humans and animals, while reducing tick populations, infestations and circulation of pathogens. The development and application of mRNA vaccines for tick and tick-borne pathogens represent a comprehensive strategy in global health, fostering a healthier ecosystem for all species in our interconnected world.

Disease-modifying therapies (DMTs) impact the cellular immune response to severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) vaccines in patients with multiple sclerosis (pwMS). In this study, we aim to elucidate the characteristics of the involved antigen-specific T cells via the measurement of broad cytokine profiles in pwMS on various DMTs. We examined SARS-CoV-2-specific T cell responses in whole blood cultures characterized by the release of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-13, IL-17A, interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α), as well as antibodies (AB) targeting the SARS-CoV-2 spike protein in pwMS following either two or three doses of mRNA or viral vector vaccines (VVV). For mRNA vaccination non-responders, the NVX-CoV2373 protein-based vaccine was administered, and immune responses were evaluated. Our findings indicate that immune responses to SARS-CoV-2 vaccines in pwMS are skewed towards a Th1 phenotype, characterized by IL-2 and IFN-γ. Additionally, a Th2 response characterized by IL-5, and to a lesser extent IL-4, IL-10, and IL-13, is observed. Therefore, the measurement of IL-2 and IL-5 levels could complement traditional IFN-γ assays to more comprehensively characterize the cellular responses to SARS-CoV-2 vaccines. Our results provide a comprehensive cytokine profile for pwMS receiving different DMTs and offer valuable insights for designing vaccination strategies in this patient population.

Current mRNA vaccines are mainly administered via intramuscular injection, which induces good systemic immunity but limited mucosal immunity. Achieving mucosal immunity through mRNA vaccination could diminish pathogen replication at the entry site and reduce interhuman transmission. However, delivering mRNA vaccines to mucosae faces challenges like mRNA degradation, poor entry into cells, and reactogenicity. Encapsulating mRNA in extracellular vesicles may protect the mRNA and reduce reactogenicity, making mucosal mRNA vaccines possible. Plant-derived extracellular vesicles from edible fruits have been investigated as mRNA carriers. Studies in animals show that mRNA vehiculated in orange-derived extracellular vesicles can elicit both systemic and mucosal immune responses when administered by the oral, nasal, or intramuscular routes. Once lyophilized, these products show remarkable stability. The optimization of mRNA to improve translation efficiency, immunogenicity, reactogenicity, and stability can be obtained through adjustments of the 5\'cap region, poly-A tail, codons selection, and the use of nucleoside analogues. Recent studies have also proposed self-amplifying RNA vaccines containing an RNA polymerase as well as circular mRNA constructs. Data from parenterally primed animals demonstrate the efficacy of nasal immunization with non-adjuvanted protein, and studies in humans indicate that the combination of a parenteral vaccine with the natural exposure of mucosae to the same antigen provides protection and reduces transmission. Hence, mucosal mRNA vaccination would be beneficial at least in organisms pre-treated with parenteral vaccines. This practice could have wide applications for the treatment of infectious diseases.