摘要：

This chapter presents the procedure for purification and assaying of leukocyte elastase. Leukocytes for use as starting material in the purification of leukocyte elastase are most conveniently obtained by leukapheresis of patients with chronic myeloid leukemia, or normal donors. The purification procedure involves following steps: homogenization and centrifugation to obtain supernatant; adsorbtion of extract batchwise with the aprotinin- Sepharose; chromatography on carboxymethyl-cellulose. Elastase isolated in this way showed only protein bands attributable to the recognized isoforms, when run in SDS- 20% polyacrylamide gels, and in gels at acid pH. Leukocyte elastase has been assayed with a wide variety of substrates, including elastin, other proteins, and a number of synthetic substrates. Assays with elastin are not normally to be recommended for routine use; variables introduced by the fact that the substrate is insoluble militate against precision.

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