Cloning and Expression of Human Gamma-Interferon cDNA in E. coli

Prior to the production of human gamma interferon using recombinant DNA technology, it had been producedmainly upon mitogenic induction of lymphocytes in very low amounts, which evidently hamperedits characterization and its medical applications. The recombinant gamma interferons produced in largerquantities in prokaryotic systems retain their biological activities, and can be used clinically in the treatmentof various viral, neoplastic and immunosuppressed conditions or diseases. In this study, a cDNAsequence coding for human gamma interferon was synthesized from mRNA template extracted frominduced human T lymphocytes. The cDNA was then amplified by PCR, cloned in an expression vector,and transformed into Escherichia coli. The polypeptide produced through the expression of this DNAsequence in E. coli showed immunological and chemical properties resembling authentic human IFN-γ.