ABSTRACT
This chapter considers the lessons learned – and the questions raised – by intracellular ribozyme experiments to date, with special attention to the aspects of ribozyme delivery. It examines various strategies for enhancing interaction of ribozyme and substrate in an intracellular environment. The chapter discusses both investigative and therapeutic applications of ribozymes. It explores the various synthetic options afforded by modern chemical ribonucleic acid (RNA) synthesis. The modalities used for ribozyme delivery may be broadly classified as either delivery of exogenously synthesized ribozyme or "gene therapy": some type of vector is used to insert a ribozyme-encoding gene into the desired cells, to be maintained in either an episomal or chromosomally integrated state. The chemical stability of ribozyme RNAs is a prime consideration for exogenous delivery. The chapter suggests that stable ribozyme expression might well be feasible through direct delivery of a ribozymeencoding gene to the tissue of interest, particularly if the tissue lends itself to such delivery methods.
