Table 1.

Representative purification of DPP4 from Sf9 cells.

	Volume (mL)	Protein (mg/mL)	Total Protein (mg)	Total Activity (U)	Specific Activity (U/mg)	Fold-Purification *	Yield (%) **	Step-Wise DPP4 Loss (%) #	Step-Wise Total Protein Loss (%) ##
Cell culture supernatant	1000	7.3	7300	144	0.020	1	100	0	0
35% AS	1046	3.9	4079	109	0.027	1.4	76	24	44
80% AS	82	7.2	589	85	0.14	7.0	59	22	86
Phenyl Sepharose	93	4.1	381	77	0.20	10	53	9.4	35
Ni Sepharose	41	0.034	1.4	64	46	2300	44	16	99.6
DEAE Sepharose	4.4	0.23	1.0	42	42	2100	29	35	29

* Fold-purification is specific activity after the step/specific activity of the starting material (cell culture supernatant). ** Yield is Units of DPP4 as a % of DPP4 Units in the starting material. # Step-wise DPP4 loss (%) is 100 × (total activity after the previous step − total activity after this step)/total activity after the previous step. ## Step-wise total protein loss (%) is 100 × (total protein after previous step − total protein after this step)/total protein after the previous step.