Study of cytotoxicity of Bacillus anthracis recombinant protective antigen in form of free and encapsulated by double-block PLA-PEG and PCL-PEG copolymers on the Vero cell

Document Type : Original Article


1 تهرانپارس- انتهای اتوبان شهید بابایی- خیابان شهید چمن آرا- جنب دانشگاه آزاد تهران شمال- خوابگاه دانشجویی حضرت ولیعصر عج

2 Genetic master science researcher of biological science department, Imam hossein comprehensive university. Tehran, Iran.

3 School of Technology, Tarbiat Modarres University, Tehran, Iran.

4 Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran


Background & Purpose: Bacillus anthracis is the cause of the fatal anthrax. Using of vaccine is one of the effective ways to combat anthrax. Vaccines should be biocompatible and non-toxic. The purpose of this study was to investigate the effect of Bacillus anthraise recombinant protective, free and encapsulated antigen cytotoxicity by double-block PLA-PEG and PCL-PEG copolymers on the epithelial cell line of the African green monkey (Vero), in order to obtain the amount of the destructive effect of this candidate as the vaccine.
Materials & Methods: In this experimental study, the Bacillus anthraise recombinant protective antigen (PA63) was expressed in E. coli and purified by nickel column affinity chromatography. Subsequently PA63 was encapsulated by PLA-PEG and PCL-PEG double-block copolymers using water-in-oil-in-water solvent evaporation method. Finally, PA63 and nanoparticles cytotoxicity test were performed using the standard MTT test on the Vero cell line.
Results: Results of the MTT test revealed the non-toxicity of the candidate vaccine. Also, the mortality rate of the cells tested against the encapsulated antigen in the nanoparticles was lower than the free antigen.
Conclusion: According to the results, the nano-vaccine formulation can be used to reduce the toxicity of a vaccine produced and eventually acquire an effective and biocompatible recombinant vaccine.


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