Expression of the Recombinant Protein Containing CfaB, ST, CfaE, and LtB from Enterotoxigenic Escherichia coli and Loading It in Chitosan Nanoparticles

Aims: Enterotoxigenic Escherichia coli (ETEC) is the most important bacteria causing traveler’s diarrhea. The bacterium has several virulence factors, including colonization factors (CFs) or Escherichia coli adhesins, heat-labile (LT), and heat-stable (ST) toxins. The design and production of vaccine against this disease is one of the goals of the World Health Organization due to increased antibiotic resistance and a reduction of healthy water sources. An effective subunit vaccine against ETEC could include a toxoid from both toxins and colonization factors. The aim of the current study was to express, purify, and encapsulate the recombinant protein in chitosan nanoparticles. Materials and Methods: In the present experimental study, the E. coli BL۲۱DE۳ harbring pET-۲۸a-cscl vector was used. The chimeric cscl gene is composed of cfab along with st toxin, cfae, and ltb. After the expression and purification of recombinant protein, using Ni-NTA column, Western blotting was performed with anti-His antibody. Then, the CSCl protein was encapsulated in chitosan nanoparticles and the particle size was measured. Findings: The recombinant CSCL protein was purified by Ni-NTA column and urea denaturation method. Then, this purified protein (~۵۷kDa) was confirmed by Western blotting and the size of the nanoparticles was estimated as ۱۱۲.۰ nm with ۹۸.۸% of encapsulation efficiency. Conclusion: With some advantages, including the presence of surface and important antigens of ETEC and encapsulating in chitosan nanoparticles, the CSCL recombinant protein can be considered as a candidate for producing oral nanovaccine and stimulating of mucosal and systemic immune response.

کلیدواژه ها:

Enterotoxigenic Escherichia coli ، Heat-labile toxin ، Heat-stable toxin ، Chitosan nanoparticles ، Escherichia coli adhesins ، Traveler’s diarrhea ، اشریشیا کلی انتروتوکسیژنیک ، توکسین حساس به حرارت ، توکسین پایدار به حرارت ، نانوذرات کیتوسان ، عوامل کلونیزاسیون ، اسهال مسافرتی