Evaluation of lesion Development and Type of Immune Response Generated in Mice Inoculated with L. major mixed with LPD Nanoparticles Containing CpG ODN

The inoculation of live, non attenuated Leishmania major to produce a lesion in a selected site that heals, referred to as leishmanization, is to date the only vaccine against leishmaniasis that has proven to be effective in humans. Its use has been restricted or abandoned entirely, however, due to safety concerns. In an attempt to develop a leishmanization protocol that minimizes pathology while maintaining long-term protection, live parasites were coinjected with lipid protammin (LP) containing immunostimulatory oligodeoxynucleotides (CpG ODNs), (LPD), a novel and improved vaccine and/or adjuvant delivery system actively sought to enhance the potency of vaccines. BALB/c mice infected subcutaneously by using L. major plus LPD nanoparticles, developed few dermal lesions and showed an early containment of parasite growth, while mice infected with L. major plus CpG ODNs in soluble form or phosphate-buffered saline (PBS) developed sizable dermal lesions. In addition, analysis of IgG1 and IgG2a antibody as a marker of Th2 and Th1 immune response, respectively, laid emphasis on this fact. Our results suggest that immune modulation using LPD nanoparticles might be a practical approach to improving the safety of a highly effective live vaccine.

کلیدواژه ها:

Vaccine ، Lipid based nanoparticle ، CpG ، ODNs ، L. major