Ribozyme-mediated Cleavage Of Timp-1 Of Hypertrophic Scar In Vitro

Ribozyme is firstly introduced by Cech in 1987 to describe some kind of RNA having the character of enzyme. It's finding provided a more special method for gene therapy. People designed kinds of ribozymes taking advantage of its property of intermolecular cleavage to block the expression of intended RNA.Presently, it has been studied on malignant tumor, virus hepatitis and Aids to improve the gene therapy of these diseases and some success has been achieved. Ribozyme is composed of one very conservative core sequence recognizing the sequence NUX and two flanking sequences homologous to target RNA. When flanking sequences combined with RNA, cleavage happened at the site of selected position. This blocked the further expression of the intended RNA. Ribozyme have been proved more efficient than antisense nucleic acid in many studies, perhaps owning to its property of enzyme so it can be used repeatedly. Scar is the inevitable result of healing. But excess scarmay lead to deformity anddysfunction, which is HPS. The core problem of HPS is too much deposition of collagen resulted from the unbalance between the collagen抯 synthesis and degradation. In the past, studies focused on decreasing the synthesis but recently they have been turned to improving the degradation. And it has a prospect because the form of HPS is not only owning to the increase in the synthesis but to the relatively less decrease in degradation in the later period. Collagenase is the specific 6 enzyme to analyze I. II types of collagen. Studieshave proved abnorma1 mode of Collagenase is thekey reason why HPS formed and wou1dn' t disappear.And the problem may be resolved by improvingCol lagenase l s function.TIMP--l is one of the most effective peptideamong the family of TIMP, which modu1ate thefunction of Co1lagenase. And it may be the valvein the process of collagen l s degradation. TIMP--lfunctions through the formation of a tight, l: lcomplex with active Collagenase. As a result, theactivation and autoactivation of Collagenase arecut down. At the same time, TIMP--l strongly promotethe proliferation of FB and mediate the actionof some factors such as TGF0. Recent studies madeit clear that TIMP--l express itself in a much higherway and the hiqh concentration last out, whichresulted in HPS and fibrosis. We take TIMP--1 mRNAas our researchinq ob j ect. Computer is used toassist the design of ribozymes and p1asmidstranscript the ribozymes have been estab1ishedto produce abundant ribozymes. Abnorma l col1agenmetabolism is controlled throuqh the cleavage ofTIMP--1 mRNA to inhibit its expression. It is anew way to settle the problem of HPS. And it alsoh a s a g r e a t p r o m i s e...