Table 1. GCase Inhibitory Activity and Maximum Observed Increase in GCase Activity Using Pharmacological Chaperones and NN-DNJ.

	imiglucerase
	IC50 (μM)
compd	pH 7.0	pH 5.2	Kia (μM)	% GCase inhibitionb	N370S GCase activity increasec	L444P GCase activity increasec
1	0.081	0.64	0.17	50	1.6 ± 0.1 (1 μM)	1.3 ± 0.2 (1 μM)
2	0.056	0.09	0.026	96	1.6 ± 0.2 (0.1 μM)	1.3 ± 0.1 (1 nM)
3	1.21	1.61	0.70	36	2.0 ± 0.1 (10 μM)	no activity
4	44.4	53.4	n.d.d	17	1.2 ± 0.1 (10 μM)	n.d.
5	n.d.	46%e	n.d.	n.d	n.d.	n.d.
6	49.3	144.0	n.d.	n.d.	n.d.	n.d.
NN-DNJ	0.30	0.66f	0.30f	56g	1.4 ± 0.1 (5 μM)	no activity

^aCompetitive inhibitor (pH 5.2).

^bIncubation for 24 h at 5 μM inhibitor and 5 mM substrate in wild-type (wt) human fibroblast.

^cN370S and L444P lymphoblasts from Gaucher patients were incubated with test compounds for 3 days before being used for enzyme assay. Data in parentheses correspond to the concentration of the tested compound. Experiments were performed in triplicate, and the mean ± SD is shown. The relative activity was obtained by normalizing the activity corresponding to each compound concentration tested to the activity of untreated cells.

^dn.d.: not determined.

^e% inhibition at 1 mM inhibitor.

^fSee ref (22).

^gIncubation for 24 h at 50 μM inhibitor and 5 mM substrate.