Vaccine
Vaccine
4 years ago

Raw starch microparticles have immunostimulant activity in mice vaccinated with BCG and challenged with Mycobacterium tuberculosis

The main challenge for vaccine development or improvement is the lack of safe adjuvants or immunostimulants that induce protective immune responses and can be used for mucosal immunization, which is a highly desirable strategy for vaccination against infectious diseases acquired by oral or intranasal routes. One promising alternative is the use of biodegradable and biocompatible polymeric microparticles. Recently, we developed an immobilization and delivery system with starch microparticles (SMPs) and a starch-binding domain (SBDtag) suitable for the mucosal administration of antigens and the induction of antigen-specific immune responses. Here, we explore the immunostimulant and reinforcing potential of the system using BALB/c mice with progressive pulmonary tuberculosis (PPT). The heat shock protein alpha-crystallin from Mycobacterium tuberculosis immobilized on SMPs (µAcr-SBDtag) or SMPs alone were administered nasally as boosters to BCG-vaccinated mice without any extra adjuvant. The mice were challenged intratracheally with either moderately virulent or highly virulent M. tuberculosis strains. Our results showed that the administration of either the immobilized antigen or SMPs asa booster for the BCG vaccination induced a significant reduction of bacterial loads in the lungs of mice, even more than in mice that received the BCG vaccination alone. Since no difference was observed in pulmonary bacillary burdens between the two reinforced groups, the obtained effect was most likely primarily caused by the starch. As determined by histological study, the administration of boosters did not contribute to the progress of pneumonia, which diminishes the safety concerns related to the administration of SMPs intranasally. Taken together, our findings suggest that this system may be considered asa new carbohydrate-based adjuvant suitable for mucosal vaccines against tuberculosis and other infectious diseases, and more generally, they highlight the potential of particulate α-glucans as immune response modifiers.

Publisher URL: www.sciencedirect.com/science

DOI: S0264410X17310794

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.