Table 1.

Analysis of Cathepsin B and H Expression in Cells Isolated from 9L-GFP Tumor Xenograft.^*

Cell Type	Primer Specificity	Amplified Fragment Size (bp)	Normalized Signal Intensity	Specific Cathepsin B Activity (U/ml cells)*
GFP-positive	Rat cathepsin B	162	101.8	0.015
	Rat cathepsin H	529	143.5
	Mouse cathepsin B**	160	117.2
	Mouse cathepsin H	532	14.1
GFP-negative	Rat cathepsin B	162	5.8	0.058
	Rat cathepsin H	529	7.6
	Mouse cathepsin B**	160	354.3
	Mouse cathepsin H	532	44.8

^*Specific activity was determined using a fluorescent substrate as described in Materials and Methods.

^**Primers specific for mouse cathepsin B are not species-specific.