en زیست شناسی ملکولی Molecular Biology مقالات اصلی Original Article <div style="text-align: justify;"><strong><em>Background:</em></strong> It is estimated that one third of the world&#39;s population is infected with Mycobacterium tuberculosis (Mtb), the causative agent of Tuberculosis (TB). The BCG vaccine is widely used to fight against TB; however, many question its ability to provide complete protection from Mtb. Recently, the &quot;Region of Difference 1&quot; (RD1) set of genes were shown to be involved in the pathogenesis of Mtb. Downstream of RD1 transcription region, two proteins are encoded, known as EspB and EspC, which were found to contribute to Mtb virulence. In this study these two proteins are targeted as potential vaccine candidates against TB.<br> <br> <strong><em>Methods:</em></strong> The EspB and EspC Mtb genes were codon-optimized for expression and synthesis in Escherichia coli (E. coli). The amplicons were cloned into a pET21a expression vector and transformed into E. coli BL21(DE3). The expression and purity of the expressed proteins (i.e. rEspC, rEspB and rEspC/EspB) were confirmed by SDS-PAGE and Western blotting. Moreover, BALB/c mice were immunized against Mtb using the recombinant proteins. Finally, the mice sera were analyzed via Western blotting.<br> <br> <strong><em>Results:</em></strong> EspC, EspB, and EspC/EspB fusion genes were cloned and expressed in E. coli. Both SDS-PAGE and Western blots confirmed the presence and successful purification of the desired proteins. Moreover, antisera produced against the purified recombinant proteins reacted with Mtb proteins.<br> <br> <strong><em>Conclusions: </em></strong>rEspC, rEspB, and rEspC/EspB could be expressed and purified using an E. coli expression system. The recombinant proteins induced the production of antibodies in BALB/c mice that reacted with Mtb proteins.</div> EspB, EspC, ESX-1, Mycobacterium tuberculosis. 465 472 http://rbmb.net/browse.php?a_code=A-10-139-3&slc_lang=en&sid=1 Omid Salemi omid.salemi@yahoo.com 100319475328460017465 100319475328460017465 No Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Zahra Noormohammadi z-nouri@srbiau.ac.ir 100319475328460017466 100319475328460017466 No Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Fariborz Bahrami fariborz.bahrami@mail.mcgill.ca 100319475328460017467 100319475328460017467 No Pasteur Institute of Iran, Department of Immunology, 69 Pasteur Ave., Tehran 13169-43551, Iran. Seyed Davar Siadat zahra.hashemi1987@yahoo.com 100319475328460017468 100319475328460017468 No Pasteur Institute of Iran, Mycobacteriology and pulmonary research, 69 Pasteur Ave., Tehran, Iran. Soheila Ajdary sohary@yahoo.com 100319475328460017469 100319475328460017469 Yes Pasteur Institute of Iran, Department of Immunology, 69 Pasteur Ave., Tehran 13169-43551, Iran.