The goal of the project is to use recombinant technique to produce Human Elastase Inhibitor (HEI) so that its potential as anti-inflammatory pharmaceutical agent can be evaluated. The known properties of HEI, one of very few naturally occurring human inhibitors of elastase, indicate that it will likely serve as pharmaceutical agent in a variety of inflammatory conditions in which excess action of the powerful neutrophil protease elastase causes tissue damage. These include emphysema, cystic fibrosis, asthma, arthritis and several-skin diseases. HEI, which is found in blood monocytes and neutrophils, has been purified (in small amounts) from a human cell line and its cDNA sequence and several important characteristics of the protein have been determined. The major block to the development of HEI as anti-inflammatory agent is the absence of a supply of the pure protein. Pure HEI is needed in sufficient quantities so that additional properties (comparisons, stability, side-effects etc.) can be examined and its suitability as pharmaceutical agent can be evaluated. The project aims to produce recombinant HEI. The available starting materials are a cDNA clone encoding the full-length molecule and a simple and specific assay that can be used to screen expression systems. The major goal is to make an expression construct, to be generated from the existing full length cDNA clone and a commercial vector and to express the construct in the baculovirus/insect cell system. Goals of Phase II will include scaling up of the protein expression system and purification of the recombinant protein.
