Evaluation of the Antimicrobial and Antibio film Effect of Chitosan Nanoparticles as Carrier for Supernatant of Mesenchymal Stem Cells on Multidrug-Resistant Vibrio cholerae

Aim: The aim of the present study was to evaluate the in vitro antimicrobial and antibiofilm activity of chitosan nanoparticles (CS NPs) incorporated with mesenchymal stem cellsderived conditioned media (MSCs CM) on MDR Vibrio cholerae strains. Materials and Methods: Chitosan NPs were prepared and characterized by dynamic light scattering (DLS), scanning electron microscope (SEM) and zeta potential measurement. MSCs CM were prepared and entrapped into MSCs CM-CS NPs composite and its release efficiency was measured. Antibacterial efficacy of nano structures was determined by disk diffusion and broth microdilution methods. Antibiofilm activity was assessed by crystal violet assay. Results: BM-MSCs were characterized to be negative for CD34 and CD45markers, positive for CD73 and CD44 markers, and able to differentiate into osteoblast and adipocyte cells. The mean particle size of 96.6% of chitosan NPs was 414.9 nm with a suitable zeta potential and SEM morphology. Entrapment efficiency of MSCsCM-CS NPs was 76.9%. UnstimulatedMSCsCMCS NPs composite as a novel and proficient therapeutic nanostructure against MDR V. cholerae strains showed the synergistic activity of the two components ofMSCs CM and CS NPs, leading to greater bacterial killing compared to control groups. MSCs CM more efficiently inhibited biofilm formation, although MSCs CM-CS NPs was also appeared to be effective in inhibiting biofilm formation compared to CS NPs and control group. Conclusion: The designed nanodrug composite showed the best release in conditions mimicking the physiological conditions of the intestinal lumen. Given the fact that no overuse or genetic event would cause the emergence of antimicrobial resistance against the MSCs CM-CS NPs nanodrug, it could be considered as a promising alternative for the treatment of MDR V. cholerae infections in clinical settings.