Cloning, expression and library construction for HIV-1 Tat Protein

Background: Designing novel therapeutic agents has been a critical challenge for HIV disease. Materials and Methods: In current study a DNA sequence which was encoded the Tat protein was synthesized and inserted in pET 28 vector. Vector was cloned in BL21-DE3 E. coli and cultured in TB media. After protein expression, recombinant Tat protein was purified by NTA affinity chromatography. The Tat purified protein efficiency and confirmed by SDS-PAGE and Western blot, respectively. We were immunized the camel against HIV-1 Tat recombinant protein to made a camelid antibody library. Total RNA was extracted from camel lymphocytes and VHH fragments synthesized and amplified using RT-PCR and Nested- PCR methods by special primers. Results: The 350- 450 bp VHH gene fragment was produced by RT-PCR and Nested- PCR and extracted from agarose gel 1%. Then gel extraction was performed and pure fragments were inserted in HEN-4 vector by T4 DNA ligase. Conclusion: The library can be applied for biopanning and isolation of nanobody against HIV-1 Tat Protein. Nanobody small size may be a useful drug for treatment of HIV disease because give them the potency of the recognizing the cryptic epitopes of tat and neutralized the virus.