Design and Evaluation of cruzipain gene using Saccharomyces cerevisiae as a vaccine vector against Trypanosoma cruzi experimental infection

Chagas disease, or American trypanosomiasis, is caused by Trypanosoma cruzi, a hemoflagellate Trypanosomatidae family parasite, widely distributed in the American tropics and subtropics. Cruzipain (Cz) is a crucial parasitic proteases belong to the papain-like CA C1 family and have close structural mammalian homologues and considered to be a good vaccine candidate for Chagas disease. Cz full gene sequence was obtained from GenBank Acc. No. AY099317.1 and redesigned in silico, sequences were sent to be synthesized and cloned into Sc expression plasmids (pYES-2, Invitrogen) in Genscript Company (USA). pYES-CZ recombinant plasmid was transformed into DH5α E.coli strain for its selection and production. Plasmidic DNA was extracted and transfected to INVSc1 Saccharomyces cerevisiae strain, then cultivated and selected through ura3-52 deficient medium. Finally, transfected Sc were evaluated as a potential vaccine against Chagas disease in 8 weeks female BALB/c mice. Results showed that modified cruzipain gene construct was successfully stable during its transfection in bacteria then in Sc, moreover amplification results showed a unified linear DNA with the desired size. Data showed that transfected recombinant Sc elevates lymphocyte responses and gives remarkable results. Lastly Sc and Cz are promising vaccine candidates against T. cruzi experimental infection, further investigation would be required for establishing a strong therapy for the population at risk of the infection.