Generation of Recombinant Human Ache Op-Scavengers With Extended Circulatory Longevity
Abstract
The use of recombinant human acetylcholinesterase as an effective bioscavenger of organophosphorus compounds requires that it reside in the circulation for sufficiently long periods of time. We have demonstrated in the past that extension of the circulatory lifetime of AChE can be achieved either by optimizing post-translation-related enzyme processing or by chemical conjugation of polyethylene glycol (PEG) moieties to the enzyme. To delineate the interrelationship between these two modes of AChE modulation with regard to pharmacokinetic behavior, an array of AChE molecules differing in their post-translation-related processing was subjected to PEG-conjugation and monitored for their pharmacokinetic performance. In all cases tested to date, PEG-conjugation was found to give rise to enzyme species which reside for very long periods of time in the circulation of mice in a nearly equal manner. We have now found a novel mode of AChE circulatory elimination based on the recognition of specific amino acid-related epitopes. This unique clearance mechanism can also be efficiently overcome by enzyme PEGylation. These findings indicate that the circulatory residence is dictated primarily by the PEG appendage, and that cost-effective microorganisms-based production systems which do not support animal-cell-related enzyme processing, may be utilized for large-scale AChE production. In line with this notion, we have constructed a synthetic human AChE gene designed for optimal expression in microorganism-based production systems, which will now be tested for its ability to sustain human AChE production.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2004
- Accession Number
- ADA423711
Entities
People
- Avigdor Shafferman
Organizations
- Israel Institute for Biological Research