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

• Published in: Life sciences (1973) 2020-09, Vol.256, p.117961, Article 117961
• Main Authors: Pandey, Ramendra Pati, Kumar, Santosh, Ahmad, Saheem, Vibhuti, Arpana, Raj, V. Samuel, Verma, Anita Kamra, Sharma, Pawan, Leal, Elcio
• Format: Article
• Language: English
• Subjects: Antigens; Cell culture; CFU; Chitosan; Chitosan nanoparticles; Encapsulation; Filtrate; Immunization; Lymphocytes; Lymphocytes T; Mycobacterium tuberculosis; Nanoparticles; Proteins; Tuberculosis
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2020.117961

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. Chitosan nanoparticles encapsulated into antigenic proteins of Mycobacterium tuberculosis. (1) The chitosan nanoparticles (CHNP) were prepared by Inotropic gelation method. (2) Culture filtrate proteins (CFP) from Mycobacterium tuberculosis (Mtb) were encapsulated into the nanoparticles. (3) Female Balb/c mice were immunized with CFP-encapsulated nanoparticles via intraperitoneal routes thrice at an interval of three weeks. (4) Mice were exposed for 30 min in a Madison aerosol chamber, by nebulizing 5 ml of a bacterial suspension of H37Rv in 0.9% NaCl solution at a concentration of 2 × 106 bacilli/ml. (5) Mice were sacrificed 10- and 60-days post infection and Colony Forming Unit Assay (CFU) was performed. [Display omitted] •Chitosan nanoparticles were prepared in the size range of ~250 to ~300nm•Having a zeta potential +41mV•Entrapment efficiency for CFP-10 ~16% and for CFP-21 ~18%•The FTIR studies indicated that the chitosan nanoparticles there was a distinct shift of the peak to 1564.03cm-1 due to the wagging of NH2 bond•The IFN-γ level demonstrated a Th1 biased T cell response in an ex vivo assay•The GST levels were lowered indicating oxidative on Day 7.•Enhanced GST levels was observed on day 21 indicated reduced or no oxidative stress.•Protection was induced in ChN- CFP-10 immunized mice as compared to CFP-10 per se.•Remarkably, in the group of mice immunized with ChN-CFP-10 the number of co