Inhibition of interleukin-1 beta (IL-1 beta) production in human cells by ribozymes against IL-1 beta and IL-1 beta converting enzyme (ICE)

We and others have shown previously that hairpin ribozyme genes, when stabl y expressed in cells, can reduce the steady-state levels of target mRNA and their cognate proteins. Despite this capability, ribozymes have not been a s widely used in knockdown experiments as one might expect, probably becaus e specific rules governing the selection of ribozymes that will have high a ctivity have not been described; In this report, we show that parallel scre ening of less than 10 ribozyme expression constructs, with no advanced know ledge of cleavage activity or preselection, can efficiently identify knockd own ribozymes. This empirical selection study, which used interleukin-lp (I L-1 beta) and IL-1 beta converting enzyme (ICE) as example targets, resulte d in (1) the rapid identification of ribozymes that can reduce the producti on of IL-1 beta in THP-1 cultures by 10-fold and (2) the consequent direct generation of stable knockdown cell lines, We conclude, based on these and similar studies, that parallel screening of ribozyme constructs could be us ed in high throughput gene functional analysis programs as a means of rapid ly generating specific knockdown cell lines.