Development and evaluation of cell membrane-based biomimetic nanoparticles loaded by Clostridium perfringens epsilon toxin: a novel vaccine delivery platform for Clostridial-associated diseases

The efficacy of egg albumin nanoparticles adjuvanted Clostridium perfringens type D toxoid vaccine in rabbits

Epsilon toxin (ETX) is an exotoxin produced by Clostridium perfringens type D that induces enterotoxaemia or necrotic intestinal infection in small ruminants and bovine. Immunization is an essential element in preventing the spread of infectious diseases. In recent literature, nanocarriers have exhibited the capacity to deliver protection, stability, and regulated distribution properties to protein-based antigens. Furthermore, egg albumin is a highly adaptable protein nanocarrier in vaccine delivery systems due to its biocompatible, biodegradable, non-toxic, and non-immune-modulating properties. In this study, we assessed the efficacy, safety, immunogenicity, and dose-effect relationships of the nanoparticle-advanced toxoid vaccine (G1) in contrast to the commercially available vaccine (ETV) (G2). Two different vaccines (1 ml) were inoculated in experimental animals (rabbits) on days 1, 7, 14, 21, and 28. The geometric mean titers (GMT) of Groups 2 and 3 were recorded on the respective day of inoculation. The findings reveal that the GMT of group 2 was significantly higher than group 3. The use of nanoparticles to detain toxins demonstrated enhanced immune protection against the harmful effects caused by the toxins. This work is anticipated to explore new opportunities in developing improved vaccinations using nanoparticles to combat the pathogenicity/ virulence factors that present potential risks to livestock.

The Molecular Architecture and Mode of Action of Clostridium perfringens ε-Toxin

Clostridium perfringens ε-toxin has long been associated with a severe enterotoxaemia of livestock animals, and more recently, was proposed to play a role in the etiology of multiple sclerosis in humans. The remarkable potency of the toxin has intrigued researchers for many decades, who suggested that this indicated an enzymatic mode of action. Recently, there have been major breakthroughs by finding that it is a pore-forming toxin which shows exquisite specificity for cells bearing the myelin and lymphocyte protein (MAL) receptor. This review details the molecular structures of the toxin, the evidence which identifies MAL as the receptor and the possible roles of other cell membrane components in toxin binding. The information on structure and mode of action has allowed the functions of individual amino acids to be investigated and has led to the creation of mutants with reduced toxicity that could serve as vaccines. In spite of this progress, there are still a number of key questions around the mode of action of the toxin which need to be further investigated.

Nanotechnology's frontier in combatting infectious and inflammatory diseases: prevention and treatment

Inflammation-associated diseases encompass a range of infectious diseases and non-infectious inflammatory diseases, which continuously pose one of the most serious threats to human health, attributed to factors such as the emergence of new pathogens, increasing drug resistance, changes in living environments and lifestyles, and the aging population. Despite rapid advancements in mechanistic research and drug development for these diseases, current treatments often have limited efficacy and notable side effects, necessitating the development of more effective and targeted anti-inflammatory therapies. In recent years, the rapid development of nanotechnology has provided crucial technological support for the prevention, treatment, and detection of inflammation-associated diseases. Various types of nanoparticles (NPs) play significant roles, serving as vaccine vehicles to enhance immunogenicity and as drug carriers to improve targeting and bioavailability. NPs can also directly combat pathogens and inflammation. In addition, nanotechnology has facilitated the development of biosensors for pathogen detection and imaging techniques for inflammatory diseases. This review categorizes and characterizes different types of NPs, summarizes their applications in the prevention, treatment, and detection of infectious and inflammatory diseases. It also discusses the challenges associated with clinical translation in this field and explores the latest developments and prospects. In conclusion, nanotechnology opens up new possibilities for the comprehensive management of infectious and inflammatory diseases.