Mucosal vaccination can raise the immunological readiness of the respiratory tract before pathogen exposure, potentially enabling protection beyond antigen-specific immunity.

Chronic hepatitis B remains a major global health challenge, affecting over 254 million individuals and causing over 1 million deaths annually. Despite current antiviral therapies effectively suppressing viral replication, functional cure rates are low due to HBV-induced immune dysfunction and exhaustion. Therefore, new therapeutic approaches to achieve immune control of HBV infection are needed. Following the systematic evaluation of multiple HBV mRNA antigen designs, we developed mRNA-1965, a trivalent therapeutic mRNA vaccine encoding nanoparticle-displayed PreS1 and PreS2 domains of HBsAg to bypass the immune interference caused by HBV subviral particles, along with mutant forms of HBV Core and Polymerase. In HBV naïve mice, mRNA-1965 immunization induced dose-dependent HBV-neutralizing antibodies and Th1-skewed CD4+ and IFNγ+ CD8+ T cell responses to all three encoded HBV antigens. In non-human primates, mRNA-1965 elicited broad antibody and T cell responses across multiple HBV genotypes. Furthermore, vaccination with mRNA-1965 achieved a strong neutralizing antibody response and complete clearance of serum and liver HBV biomarkers in in an AAV-HBV mouse model with ∼100 IU/mL baseline HBsAg. Notably, combining mRNA-1965 with immune stimulatory co-modalities targeting PD-L1 and OX40 further enhanced therapeutic efficacy in mice with ∼1000 IU/mL baseline HBsAg. Clearance of HBV in AAV-HBV mice was associated with T cell response to mRNA-encoded antigens and with activation and differentiation of Core-specific CD8+ T cells. These findings support the potential of mRNA-1965 to promote a functional cure for chronic hepatitis B by overcoming immune dysfunction and subsequently enabling robust, functional immunity.

Monoclonal antibodies (mAbs) targeting the SARS-CoV-2 receptor-binding domain are used to treat and prevent COVID-19. However, the rapid evolution of SARS-CoV-2 drives continuous escape from therapeutic mAbs. Therefore, the ability to identify broadly neutralizing antibodies (bnAbs) to future variants is needed. Here we use deep mutational scanning to predict viral receptor-binding domain evolution and to select for mAbs neutralizing both existing and prospective variants. A retrospective analysis of 1,103 SARS-CoV-2 wild-type-elicited mAbs shows that this method can increase the probability of identifying effective bnAbs to the XBB.1.5 strain from 1% to 40% in an early pandemic set-up. Among these bnAbs, BD55-1205 showed potent activity to all tested variants. Cryogenic electron microscopy structural analyses revealed the receptor mimicry of BD55-1205, explaining its broad reactivity. Delivery of mRNA-lipid nanoparticles encoding BD55-1205-IgG in mice resulted in serum half-maximal neutralizing antibody titre values of ~5,000 to XBB.1.5, HK.3.1 and JN.1 variants. Combining bnAb identification using viral evolution prediction with the versatility of mRNA delivery technology can enable rapid development of next-generation antibody-based countermeasures against SARS-CoV-2 and potentially other pathogens with pandemic potential.

A genetic approach based on the introduction of premature termination codons can attenuate SARS-CoV-2 and induce protective mucosal immunity.

A key barrier to the development of vaccines that induce broadly neutralizing antibodies (bnAbs) against human immunodeficiency virus (HIV) and other viruses of high antigenic diversity is the design of priming immunogens that induce rare bnAb-precursor B cells. The high neutralization breadth of the HIV bnAb 10E8 makes elicitation of 10E8-class bnAbs desirable; however, the recessed epitope within gp41 makes envelope trimers poor priming immunogens and requires that 10E8-class bnAbs possess a long heavy chain complementarity determining region 3 (HCDR3) with a specific binding motif. We developed germline-targeting epitope scaffolds with affinity for 10E8-class precursors and engineered nanoparticles for multivalent display. Scaffolds exhibited epitope structural mimicry and bound bnAb-precursor human naive B cells in ex vivo screens, protein nanoparticles induced bnAb-precursor responses in stringent mouse models and rhesus macaques, and mRNA-encoded nanoparticles triggered similar responses in mice. Thus, germline-targeting epitope scaffold nanoparticles can elicit rare bnAb-precursor B cells with predefined binding specificities and HCDR3 features.

Current prophylactic human immunodeficiency virus 1 (HIV-1) vaccine research aims to elicit broadly neutralizing antibodies (bnAbs). Membrane-proximal external region (MPER)-targeting bnAbs, such as 10E8, provide exceptionally broad neutralization, but some are autoreactive. Here, we generated humanized B cell antigen receptor knock-in mouse models to test whether a series of germline-targeting immunogens could drive MPER-specific precursors toward bnAbs. We found that recruitment of 10E8 precursors to germinal centers (GCs) required a minimum affinity for germline-targeting immunogens, but the GC residency of MPER precursors was brief due to displacement by higher-affinity endogenous B cell competitors. Higher-affinity germline-targeting immunogens extended the GC residency of MPER precursors, but robust long-term GC residency and maturation were only observed for MPER-HuGL18, an MPER precursor clonotype able to close the affinity gap with endogenous B cell competitors in the GC. Thus, germline-targeting immunogens could induce MPER-targeting antibodies, and B cell residency in the GC may be regulated by a precursor-competitor affinity gap.

As the world’s population grows older, vaccination is becoming a key strategy for promoting healthy aging. Despite scientific progress in adult vaccine development, obstacles such as immunosenescence and vaccine hesitancy remain. To unlock the potential of adult vaccines fully, we must enhance immunization programs, dispel misinformation, and invest in research that deepens our understanding of aging and immunity.

Antibiotic resistance is a global public health threat. Many factors contribute to this issue, with human antibiotic consumption being significant among them. Analyzing trends and patterns in consumption can aid in developing policies to mitigate the burden of antimicrobial resistance and global disparities in access to antibiotics. Using pharmaceutical sales data licensed from IQVIA, we estimate national- level trends in antibiotic consumption in 67 countries during 2016-2023 and analyze the effects of economic growth and the COVID-19 pandemic. Finally, we estimate global human consumption and project growth through 2030 assuming current trends. We find that estimated antibiotic consumption in reported countries increased 16.3% from 29.5 to 34.3 billion defined daily doses (DDDs) from 2016 to 2023, reflecting a 10.6% increase in the consumption rate from 13.7 to 15.2 DDDs per 1,000 inhabitants per day. Increases were most pronounced in upper- middle- and lower- middle- income countries. While the COVID-19 pandemic significantly reduced consumption globally, this was most pronounced in high- income countries, and in these countries, reductions in antibiotic use in 2020 were sharper, and lasted longer, than in other countries. By 2030, we project that, without reductions in rapidly developing nations, such as investments to improve infrastructure, particularly water and sanitation, along with improved access to vaccination, global antibiotic consumption will increase by 52.3% from an estimated 49.3 billion in 2023 to 75.1 billion DDDs.

Monoclonal antibodies (mAbs) targeting the SARS-CoV-2 receptor-binding domain (RBD) showed high efficacy in the prevention and treatment of COVID-19. However, the rapid evolution of SARS-CoV-2 has rendered all clinically authorized mAbs ineffective and continues to stymie the development of next-generation mAbs. Consequently, the ability to identify broadly neutralizing antibodies (bnAbs) that neutralize both current and future variants is critical for successful antibody therapeutic development, especially for newly emerged viruses when no knowledge about immune evasive variants is available. Here, we have developed a strategy to specifically select for potent bnAbs with activity against both existing and prospective SARS-CoV-2 variants based on accurate viral evolution prediction informed by deep mutational scanning (DMS). By adopting this methodology, we increased the probability of identifying XBB.1.5-effective SARS-CoV-2 bnAbs from ∼1% to 40% if we were at the early stage of the pandemic, as revealed by a retrospective analysis of >1,000 SARS-CoV-2 wildtype (WT)-elicited mAbs. From this collection, we identified a bnAb, designated BD55-1205, that exhibited exceptional activity against historical, contemporary, and predicted future variants. Structural analyses revealed extensive polar interactions between BD55-1205 and XBB.1.5 receptor-binding motif (RBM), especially with backbone atoms, explaining its unusually broad reactivity. Importantly, mRNA-based delivery of BD55-1205 IgG to human FcRn-expressing transgenic mice resulted in high serum neutralizing titers against selected XBB and BA.2.86 subvariants. Together, the ability to identify bnAbs via accurate viral evolution prediction, coupled with the speed and flexibility of mRNA delivery technology, provides a generalized framework for the rapid development of next-generation antibody-based countermeasures against SARS-CoV-2 and potentially other highly variable pathogens with pandemic potential. ### Competing Interest Statement Y.C. is listed as an inventor of provisional patent applications of SARS-CoV-2 RBD-specific antibodies involved in the study, including BD55-1205. The patent of BD55-1205 is licensed to Moderna. Y.C. is a co-founder of Singlomics Biopharmaceuticals. A.Z.W., J.H., D.M.B., D.L., T.S., L.M., T.K., K.W., C.H., S.P., and L.M.W. are full-time employees and holders of equity in Moderna Therapeutics. Other authors declare no competing interests.

Eliciting potent and broadly neutralizing antibodies (bnAbs) is a major goal in HIV-1 vaccine development. Here, we describe how germline-targeting immunogen BG505 SOSIP germline trimer 1.1 (GT1.1), generated through structure-based design, engages a diverse range of VRC01-class bnAb precursors. A single immunization with GT1.1 expands CD4 binding site (CD4bs)–specific VRC01-class B cells in knock-in mice and drives VRC01-class maturation. In nonhuman primates (NHPs), GT1.1 primes CD4bs-specific neutralizing serum responses. Selected monoclonal antibodies (mAbs) isolated from GT1.1-immunized NHPs neutralize fully glycosylated BG505 virus. Two mAbs, 12C11 and 21N13, neutralize subsets of diverse heterologous neutralization-resistant viruses. High-resolution structures revealed that 21N13 targets the same conserved residues in the CD4bs as VRC01-class and CH235-class bnAbs despite its low sequence similarity (~40%), whereas mAb 12C11 binds predominantly through its heavy chain complementarity-determining region 3. These preclinical data underpin the ongoing evaluation of GT1.1 in a phase 1 clinical trial in healthy volunteers.

The health of the planet is one objective of the United Nations' Sustainable Development Goals. Vaccines can affect not only human health but also planet health by reducing poverty, preserving microbial diversity, reduc-ing antimicrobial resistance, and preventing an increase in pandemics that is fueled partly by climate change.

Our planet is populated by at least a trillion species of microorganisms. Every life form is sustained by them and they make the planet habitable. Only a minority of them, about 1400 species, cause infectious diseases that are responsible for human morbidity, mortality, pandemics and the resulting huge economic losses. Modern human activities, environmental changes and the attempt to control infectious agents using broad spectrum antibiotics and disinfectants jeopardize the global microbial diversity. The International Union of the Microbiological Societies (IUMS) is launching a call to action to mobilize all microbiological societies globally to promote the development of sustainable solutions to control infectious agents while preserving the global microbial diversity and the healthy life of our planet.

Background Despite bacterial coinfection rates of less than 10%, antibiotics are prescribed to an estimated 75% of patients with COVID-19, potentially exacerbating antimicrobial resistance. We estimated the associations of COVID-19 cases and vaccinations with global antibiotic sales during the first two years of the COVID-19 pandemic.Methods We obtained monthly data on broad-spectrum antibiotic sales volumes (cephalosporins, penicillins, macrolides, and tetracyclines) in 71 countries during March 2020-May 2022 from the IQVIA MIDAS (R) database. These data were combined with country-month-level COVID-19 case and vaccination data from Our World in Data. We used least squares (pooled) and fixed-effects panel data regression models, accounting for country characteristics, to estimate the associations between antibiotic sales volumes and COVID-19 cases and vaccinations per 1000 people.Findings Sales of all four antibiotics fell sharply during April and May 2020, followed by a gradual rise to near pre -pandemic levels through May 2022. In fixed-effects regression models, a 10% increase in monthly COVID-19 cases was associated with 0.2%-0.3% higher sales of cephalosporins, 0.2%-0.3% higher sales of penicillins, 0.4%-0.6% higher sales of macrolides, and 0.3% higher sales of all four antibiotics combined per 1000 people. Across continents, a 10% increase in monthly COVID-19 cases was associated with 0.8%, 1.3%, and 1.5% higher macrolides sales in Europe, North America, and Africa respectively. Sales of other antibiotics across continent were also positively associated with COVID-19 cases, although the estimated associations were smaller in magnitude. No consistent associations were observed between antibiotic sales and COVID-19 vaccinations. Results from pooled regression analysis were similar to those from the fixed-effects models.Interpretation Antibiotic sales were positively associated with COVID-19 cases globally during 2020-2022. Our findings underline that antibiotic stewardship in the context of COVID-19 remains essential.

While Staphylococcus aureus ( S. aureus ) bacteria are part of the human commensal flora, opportunistic invasion following breach of the epithelial layers can lead to a wide array of infection syndromes at both local and distant sites. Despite ubiquitous exposure from early infancy, the life-long risk of opportunistic infection is facilitated by a broad repertoire of S. aureus virulence proteins. These proteins play a key role in inhibiting development of a long-term protective immune response by mechanisms ranging from dysregulation of the complement cascade to the disruption of leukocyte migration. In this review we describe the recent progress made in dissecting S. aureus immune evasion, focusing on the role of the superantigen, staphylococcal protein A (SpA). Evasion of the normal human immune response drives the ability of S. aureus to cause infection, often recurrently, and is also thought to be a major hindrance in the development of effective vaccination strategies. Understanding the role of S. aureus virulence protein and determining methods overcoming or subverting these mechanisms could lead to much-needed breakthroughs in vaccine and monoclonal antibody development.