The function of TPSAB1 (tryptase alpha/beta 1, ENSG00000172236) is as follows. Tryptase is the major neutral protease present in mast cells and is secreted upon the coupled activation-degranulation response of this cell type. May play a role in innate immunity. Isoform 2 cleaves large substrates, such as fibronectin, more efficiently than isoform 1, but seems less efficient toward small substrates (PubMed:18854315). {ECO:0000250, ECO:0000250|UniProtKB:P21845, ECO:0000269|PubMed:18854315}.