Tryptase is a member of the serine protease S1 family. It is the predominant neutral protease of the mast cell granules. Within the mast cell granule it exists as a heparin-stabilized active tetramer.

Elastase is an enzyme that digests and degrades a number of proteins including elastin, an elastic substance in the lungs and some other organs that supports their structural framework. Elastase is specifically inhibited by alpha-1 antitrypsin.

Proteins govern most biological processes and functions. Recently, much attention has been paid to study the entire protein sets available in a cell.