Nasal mucosal administration of chitin microparticles boosts innate immunity against influenza A virus in the local pulmonary tissue.
ABSTRACT Influenza virus infection remains a major health concern due to morbidity and mortality associated with epidemics and occasional pandemics. The absence of acquired immunity to antigenically distinct, emerging virus strains stresses the need for a generic drug that protects independent of vaccination. Here, we demonstrate that prophylactic administration of chitin microparticles (CMP) via the intranasal route significantly reduced lung viral titres and clinical signs. Pre-treatment boosted the innate immune response to subsequent infection by recruiting innate cells, such as neutrophils, and increasing inflammatory cytokines. Although an increase in virus-specific T cells was observed, the memory phase was diminished. Our data demonstrate that in the absence of prior exposure to influenza virus, CMP reduce clinical signs by boosting innate immunity.
- SourceAvailable from: Ali Rostami[Show abstract] [Hide abstract]
ABSTRACT: Chitin and its some derivatives are known to be non-allergic and non-toxic substances. It has been shown that chitin microparticles have immunomodulatory activities. In the present study, we investigated the in vivo immunomodulatory activities of chitin microparticles (CMPs) on L. major-infected BALB/c mice. BALB/c mice were infected with L. major promastigotes at their base of the tail. CMPs (100 μg/100 μl) were injected into the site of infection from three days before to two or eight weeks after infection at two-day intervals. Cytokine concentrations (TNF-α, IFN-γ, IL-5 and IL-10) were measured using ELISA assays. Compared to the untreated group, production of TNF-α was significantly elevated in the CMPs-treated group. Moreover, the IFN-γ/IL-5 ratio was significantly elevated in CMPs-treated infected mice (P = 0.023). Notably, the concentration of IL-10 was higher in CMPs-treated mice. These results showed that CMPs have in vivo immunomodulatory effects via the production of IFN-γ and IL-10. We also measured the onset and size of lesions in both treated and untreated mice. The average times taken for the onset of the lesion formation were 35 and 29 days for CMPs-treated and untreated mice (P = 0.023), respectively. The mean size of the lesions was smaller in CMPs-treated group. Our study serves as a basis for future investigations on the application of CMPs as a prophylactic (vaccine adjuvant) and/or therapeutic modality against leishmaniasis.Parasitology International 12/2014; 64(2). DOI:10.1016/j.parint.2014.12.007 · 2.11 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The discovery of antibiotics has helped to save the lives of an uncountable number of people. Antibiotics have been grouped in different classes based on their origin, structure, and mechanism of action. An intrinsic and acquired mechanism of antimicrobial resistance has been identified in many bacterial strains that are of high clinical importance. This has seriously jeopardized the use of antibiotics and has also caused the spread of microbes that are resistant to effective first-choice, or "first-line" drugs. Thus, sensible use of antibiotics and the search for effective alternative measures are of high importance in order to minimize the effect due to existing and emerging antimicrobial resistant microbes.
- [Show abstract] [Hide abstract]
ABSTRACT: The development of synthetic peptide-based vaccines has many advantages in comparison with vaccines based on live attenuated organisms, inactivated or killed organism, or toxins. Peptide-based vaccines cannot revert to a virulent form, allow a better conservation, and are produced more easily and safely. However, they generate a weaker immune response than other vaccines, and the inclusion of adjuvants and/or the use of vaccine delivery systems is almost always needed. Among vaccine delivery systems, micro- and nanoparticulated ones are attractive, because their particulate nature can increase cross-presentation of the peptide. In addition, they can be passively or actively targeted to antigen presenting cells. Furthermore, particulate adjuvants are able to directly activate innate immune system in vivo. Here, we summarize micro- and nanoparticulated vaccine delivery systems used in the field of synthetic peptide-based vaccines as well as strategies to increase their immunogenicity.01/2011; 2011:181646. DOI:10.1155/2011/181646