Human β tryptase enzymes have been cloned and stably expressed in Pichia pastoris as fully active tetrameric enzymes and purified by affinity chromatography. rhLung Tryptase is provided at a high concentration (2mg/ml) in minimal buffer without heparin for chromatographic studies and with glycosylation more closely resembling cadaveric enzyme as demonstrated by glycosidase digestion followed by Western analysis of the recombinant enzyme and native lung tryptase.