Immune Enhancement by the Tetra-Peptide Hydrogel as a Promising Adjuvant for an H7N9 Vaccine against Highly Pathogenic H7N9 Virus

Biogenic Selenium Nanoparticles Synthesized by L. brevis 23017 Enhance Aluminum Adjuvanticity and Make Up for its Disadvantage in Mice

The most popular vaccine adjuvants are aluminum ones, which have significantly reduced the incidence and mortality of many diseases. However, aluminum-adjuvanted vaccines are constrained by their limited capacity to elicit cellular and mucosal immune responses, thus constraining their broader utilization. Biogenic selenium nanoparticles are a low-cost, environmentally friendly, low-toxicity, and highly bioactive form of selenium supplementation. Here, we purified selenium nanoparticles synthesized by Levilactobacillus brevis 23017 (L-SeNP) and characterized them using Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicate that the L-SeNP has a particle size ranging from 30 to 200 nm and is coated with proteins and polysaccharides. Subsequently, we assessed the immune-enhancing properties of L-SeNP in combination with an adjuvant-inactivated Clostridium perfringens type A vaccine using a mouse model. The findings demonstrate that L-SeNP can elevate the IgG and SIgA titers in immunized mice and modulate the Th1/Th2 immune response, thereby enhancing the protective effect of aluminum-adjuvanted vaccines. Furthermore, we observed that L-SeNP increases selenoprotein expression and regulates oxidative stress in immunized mice, which may be how L-SeNP regulates immunity. In conclusion, L-SeNP has the potential to augment the immune response of aluminum adjuvant vaccines and compensate for their limitations in eliciting Th1 and mucosal immune responses.

Application of hydrogels in cancer immunotherapy: a bibliometric analysis

Background

Cancer immunotherapy has made significant progress in recent years, with numerous studies worldwide. Immunotherapy has had a transformative impact on oncology and autoimmune diseases. In the biomedical arena, hydrogels with good properties are widely used in cancer immunotherapy. Our study used bibliometrics to analyze the changing trends in using hydrogels for cancer immunotherapy.

Methods

From 2013 to 2023, a systematic search was conducted in the Web of Science Core Collection database to identify reviews and articles discussing the applications of hydrogels in cancer immunotherapy. The software CiteSpace was used to visually perform the bibliometric analysis in terms of research trends, countries, institutions, authors, journals, and keywords. Individual authors' productivity was assessed with the Lotka's law. The most relevant publication sources were identified by Bradford's law.

Results

A total of 422 English-language publications related to hydrogels in cancer immunotherapy were collected. The number of annual publications increased rapidly after 2021 and remained constant for the past two years. China published the most articles in this field. The institution with the maximum number of published articles was the Chinese Academy of Sciences in China. Chen. Q was the most prolific author, and Liu. Z was the second most published author. In terms of journal contributions, the journal "Biomaterials" had the highest number of publications (n = 30). Biomaterials, Advanced Functional Materials and Journal of Controlled Release were the most influential journals. Keyword analysis revealed that cancer immunotherapy, drug delivery, immunogenic cell death, tumor microenvironment, injectable hydrogels, and immune checkpoint blockade were the primary research hotspots. In recent 3 years, adoptive T-cell therapy, black phosphorus, cell capture, adaptive cell therapy, tumor microenvironment, photodynamic therapy, and sustained release were the research hotspots in this field. Our study summarizes the objective of hydrogels in cancer immunotherapy in recent years, providing a reference for potential researchers in related field.

Conclusion

This bibliometric analysis shows the progress and trend of research on hydrogels in cancer immunotherapy. This study provides a significant avenue for future investigation into current concerns and trends in research within this field.

From bacteria to biomedicine: Developing therapies exploiting NAD+ metabolism

Nicotinamide adenine dinucleotide (NAD+) serves as a critical cofactor in cellular metabolism and redox reactions. Bacterial pathways rely on NAD+ participation, where its stability and concentration govern essential homeostasis and functions. This review delves into the role and metabolic regulation of NAD+ in bacteria, highlighting its influence on physiology and virulence. Notably, we explore enzymes linked to NAD+ metabolism as antibacterial drug targets and vaccine candidates. Moreover, we scrutinize NAD+'s medical potential, offering insights for its application in biomedicine. This comprehensive assessment informs future research directions in the dynamic realm of NAD+ and its biomedical significance.

Peptide Hydrogels as Immunomaterials and Their Use in Cancer Immunotherapy Delivery

Peptide-based hydrogel biomaterials have emerged as an excellent strategy for immune system modulation. Peptide-based hydrogels are supramolecular materials that self-assemble into various nanostructures through various interactive forces (i.e., hydrogen bonding and hydrophobic interactions) and respond to microenvironmental stimuli (i.e., pH, temperature). While they have been reported in numerous biomedical applications, they have recently been deemed promising candidates to improve the efficacy of cancer immunotherapies and treatments. Immunotherapies seek to harness the body's immune system to preemptively protect against and treat various diseases, such as cancer. However, their low efficacy rates result in limited patient responses to treatment. Here, the immunomaterial's potential to improve these efficacy rates by either functioning as immune stimulators through direct immune system interactions and/or delivering a range of immune agents is highlighted. The chemical and physical properties of these peptide-based materials that lead to immuno modulation and how one may design a system to achieve desired immune responses in a controllable manner are discussed. Works in the literature that reports peptide hydrogels as adjuvant systems and for the delivery of immunotherapies are highlighted. Finally, the future trends and possible developments based on peptide hydrogels for cancer immunotherapy applications are discussed.

Peptide-Based Hydrogels: New Materials for Biosensing and Biomedical Applications

Peptide-based hydrogels have attracted increasing attention for biological applications and diagnostic research due to their impressive features including biocompatibility and biodegradability, injectability, mechanical stability, high water absorption capacity, and tissue-like elasticity. The aim of this review will be to present an updated report on the advancement of peptide-based hydrogels research activity in recent years in the field of anticancer drug delivery, antimicrobial and wound healing materials, 3D bioprinting and tissue engineering, and vaccines. Additionally, the biosensing applications of this key group of hydrogels will be discussed mainly focusing the attention on cancer detection.