In vitro biological activity of anti-C II TA hammerhead ribozyme—A novel approach for autoimmune diseases

Abstract

This study investigated the feasibility of using an hammerhead ribozyme against C II TA, a major regulator of MHC II antigens, to repress the expression of MHC II molecules on Hela cells. A hammerhead ribozyme (Rz464) specific to 463–465 GUC triplet of C II TA and its target gene were transcribed, then mixed up and incubatedin vitro. The cleavage products were analyzed by PAGE and silver-staining. Rz464 was then inserted into the pIRES2-EGFP vector (pRz464). Stable transfectants of Hela with pRz464 were tested for class II MHC induction by recombinant human interferon-gamma (IFN-γ). mRNA of C II TA was measured by RT-PCR. Our results showed that Rz464 could exclusively cleave C II TA RNA. When induced with IFN-γ, the expression of HLA-DR,-DP,-DQ on pRz464⁺ Hela was induced, and the mRNA content of C II TA decreased too. It is concluded that Rz464 could inhibit C II TA and thus the family of genes was regulated by C II TA: MHC II molecules. These results provided insight into the future application of Rz464 as a new nucleic acid drug against auto-immune diseases.

Keywords

MHC class II transactivator (C II TA) / hammerhead ribozyme / Hela cell line / autoimmune disease

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