Investigating the potential of endolysin loaded chitosan nanoparticles in the treatment of pneumococcal pneumonia

The emergence of antibiotic-resistant strains of Streptococcus pneumoniae poses an increasing threat to mankind globally. Cpl-1, a muramidase is considered as a potential alternative agent to treat drug-resistant pneumococcal strains, but lower half-life limits its therapeutic applications. As an attempt to increase the bioavailability, chitosan-based Cpl-1 delivery system was developed and characterized in an earlier study. In the present study, the chitosan-based Cpl-1 delivery system was evaluated in the treatment of pneumococcal pneumonia. Bacterial load was found to be lowest in lungs, blood, and spleen of animals treated with Cpl-1 loaded chitosan nanoparticles as compared to Cpl-1 and chitosan nanoparticles treated animals. The histopathological analysis also revealed the lowers levels of pneumococcal infection in the lungs of Cpl-1 loaded chitosan nanoparticles treated group. The inflammatory analysis showed a lower level of inflammation in the lungs of encapsulated endolysin treated as compared to free endolysin (Cpl-1) treated animals. Cytokine studies showed a significant decline in the level of pro-inflammatory and anti-inflammatory cytokines was seen in the Cpl-1 loaded nanoparticles treatment group as compared to other groups at 48 and 72 h, supporting the efficacy of treatment. Considering the increased bactericidal activity, the endolysin delivery system represents a potential therapeutic approach for treating drug-resistant cumbersome bacterial infections. The present study is first of its kind where therapeutic potential of the endolysin delivery system was investigated in an animal infection model.

Automated summary

This study evaluated the therapeutic potential of a chitosan-based Cpl-1 delivery system for the treatment of pneumococcal pneumonia. Results showed that the system effectively reduced bacterial load, inflammation levels, and cytokine production in animal models, indicating its potential as a treatment approach for drug-resistant bacterial infections.