Use Chou's 5-steps rule to evaluate protective efficacy induced by antigenic proteins of Mycobacterium tuberculosis encapsulated in chitosan nanoparticles.

The study focuses on whether antigenic proteins encapsulated in biopolymeric nanoparticles can augment protective efficacy. Chitosan nanoparticles (ChN) were prepared by ionic gelation method and Culture Filtrate Proteins (CFP) - CFP-10 and CFP-21 of Mycobacterium tuberculosis (Mtb) were encapsulated in ChN. The binding efficiency of nanoparticles with CFP-10 and CFP-21 proteins was confirmed by UV-Spectrophotometer. The efficacy of nanoparticles-encapsulated antigenic proteins administered intraperitoneal against Mtb aerosol infection was evaluated in Balb/c mice. Protection study was done by bacterial counts [CFU]. CFP-10 and CFP-21 proteins primed cells demonstrated a Th1 bias T cell response in an ex vivo assay. ChN-CFP10 and ChN-CFP21 nanoparticles have both protective and therapeutic potential against Mtb. In the group of mice immunized with CHN-CFP-10 the number of colonies reduced significantly from day 15 to day 60. ChN-CFP-21 showed maximum protection in ChN-CFP-21 immunized mice. ChN-CFP-10 and ChN-CFP-21 clearly showed enhanced protection against Mtb.