Control of the Inflammatory Process.
Abstract
We have purified the factor released by lung cells during their cultivation in vitro which permit the mitotic activity of alveolar macrophages. This factor has a molecular weight of 68,000 daltons with an isoelectric point of 4.2 and is in equilibrium with as much as 20% of the total molecular species as dimers, trimers and tetramers. This activity appears to possess the ability to inhibit trypsin and elastase but not chymotrypsin. We have also purified to electrophoretic homogeneity a macromolecular factor from aqueous extracts of lung which has a molecular weight of 82,000 daltons and also an isoelectric point of pH 4.2. This factor increases the permeability of the microcirculation in rat skin in vivo by degranulating mast cells so that they release histamine. This permeability factor is inhibited by antihistamines and also by premixture with pepstatin, an acid protease inhibitor which also is chemotactic for polymorphonuclear leukocytes in vitro. The purified permeability factor from lung has no proteolytic activity at any pH against either synthetic or natural substrates, however. This permeability producing activity appears to be concentrated in the lysosomes of alveolar macrophages. Pepstatin also possesses the ability to inhibit the permeability factor found in testicular hyaluronidase preparations; this permeability factor also degranulates mast cells and obviously pepstatin is an important inhibitor of mast cell degranulation, and hence, histamine release.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 04, 1980
- Accession Number
- ADA085977
Entities
People
- John C. Houck