ABPP, activity-based protein profiling; ABP, activity-based probe; Cat, Cathepsin; DIC, diisopropylcarbodiimide; DIEA, N,N-diisopropyl-N-ethylamine; DMEM, dulbecco's modified eagle medium; HBTU, 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate; HOBt, hydroxybenzotriazole; MHC, major histocompatibility complex; SB, sample buffer; SPPS, solid phase peptide synthesis; TBTA, tris- (benzyltriazolylmethyl)amine; TCEP, tris-(2-carboxyethyl)phosphine; TEV, tobacco etch virus.