Viral vector- and virus-like particle-based vaccines against infectious diseases: A minireview

Engineering exosomes for mRNA delivery: a review

Messenger RNA (mRNA) has emerged as a highly promising therapeutic approach with successful applications across various diseases. Developing safe and efficient carriers to preserve mRNA integrity during in vivo delivery is critical for ensuring the therapeutic efficacy of mRNA-based treatments. Exosomes, natural nanovesicles secreted by cells, possess several favorable properties, including excellent biocompatibility, low immunogenicity, the unique ability to traverse physiological barriers and to target specific cell types, which make them attractive candidates for mRNA delivery. Moreover, exosomes can be engineered to increase their yield, enhance targeting specificity, improve cellular uptake efficiency, and extend their circulation time in the bloodstream. However, several challenges must be addressed urgently, including exosome heterogeneity, scalable production methods, and the efficient encapsulation of mRNA cargo. This review highlights the advantages and limitations of exosome-based mRNA delivery systems, discusses current strategies for engineering exosomes to improve mRNA delivery, and describes their applications in disease treatment-emphasizing their potential to advance precision medicine and targeted therapies.

In vitro expression of the goose astrovirus Cap protein delivered with a duck enteritis virus vector

BACKGROUND

Goose astrovirus (GAstV) is an emerging pathogen that is widely distributed throughout China and can cause visceral gout, resulting in serious economic losses for the goose industry. Open reading frame 2 (ORF2) of this virus encodes the precursor capsid protein, which is essential for the assembly and antigenicity of these virions. To construct a bi-valent vaccine for controlling GAstV and duck enteritis virus (DEV) infection, an infectious bacterial artificial chromosome (BAC) clone of the DEV vaccine strain pDEV-EF1 was used to establish a recombinant DEV vector for GAstV ORF2 gene delivery.

METHODS

GAstV ORF2 expression frame was inserted into the US7 and US8 intergenic region of DEV genome by Red E/T two-step recombinant technology, then the recombinant virus rDEV-GAstV ORF2 was rescued by transfecting recombinant clone pDEV-GAstV ORF2 into chicken embryonic fibroblasts (CEFs). The expression of ORF2 in CEFs and formation of virus-like particles (VLPs) were analysed by Western blotting, indirect immunofluorescence assay (IFA) and immunogold electron microscopy (IEM), individually. And protein celluar localization was analysed by IFA.

RESULTS

Using this rDEV-GAstV ORF2 vector to infect CEFs was sufficient to elicit GAstV Cap protein expression, as confirmed by Western blotting and IFA. IEM also revealed the formation of VLPs within cells expressing this Cap protein.

CONCLUSIONS

DEV is a good viral vector for GAstV ORF2 gene delivery and these results provide a basis for the development of a bivalent vaccine for controlling DEV and GAstV infections.

Cardiomyocyte regeneration after infarction: changes, opportunities and challenges

Myocardial infarction is a cardiovascular disease that poses a serious threat to human health. The traditional view is that adult mammalian cardiomyocytes have almost no regenerative ability, but recent studies have shown that they have regenerative potential under specific conditions. This article comprehensively describes the research progress of post-infarction cardiomyocyte regeneration, including the characteristics of cardiomyocytes and post-infarction changes, regeneration mechanisms, influencing factors, potential therapeutic strategies, challenges and future development directions, and deeply discusses the specific pathways and targets included in the regeneration mechanism, aiming to provide new ideas and methods for the treatment of myocardial infarction.

Meeting summary: Global vaccine and immunization research forum, 2023

At the 2023 Global Vaccine and Immunization Research Forum (GVIRF), researchers from around the world gathered in the Republic of Korea to discuss advances and opportunities in vaccines and immunization. Many stakeholders are applying the lessons of Covid-19 to future emergencies, by advancing early-stage development of prototype vaccines to accelerate response to the next emerging infectious disease, and by building regional vaccine research, development, and manufacturing capacity to speed equitable access to vaccines in the next emergency. Recent vaccine licensures include: respiratory syncytial virus vaccines, both for the elderly and to protect infants through maternal immunization; a new dengue virus vaccine; and licensure of Covid-19 vaccines previously marketed under emergency use authorizations. Malaria vaccine implementation is expanding and a second malaria vaccine has been recommended by the World Health Organization. In a setback for human immunodeficiency virus vaccine development, the only remaining Phase 3 trial has been discontinued. In immunization, greater clarity is emerging on the challenges of achieving access and equity, along with strategies to address those challenges. A better understanding of behavioral and social determinants of vaccine uptake and a validated toolkit for measuring and modifying the drivers of vaccination is informing program design and service delivery, contributing to improved uptake. Implementation research, which has been essential for human papillomavirus and malaria vaccine delivery, will be critical for delivering the new respiratory syncytial virus vaccines and for many other vaccines currently in development. The growing diversity of vaccines and complexity of immunization programs are leading to greater interest in simplified regimens, combination vaccines, and other innovations to facilitate delivery. Collaboration emerged as the unifying theme of GVIRF 2023, underscoring that the combined efforts of many contributors have enabled progress thus far, and going forward will continue to be essential to ensure equitable access to vaccines for all.