Table 1.

Cysteine protease activity in saliva

	Activity,* μg/ml		Activity, μg/mg protein
	8 weeks	20 weeks	8 weeks	20 weeks
BALB/c	15.2  ±  2.6	16.7  ±  2.7	15.9  ±  2.7	12.8  ±  2.1
NOD prediabetic mice	14.8  ±  1.9	45.8  ±  5.3	10.3  ±  1.9	39.2  ±  4.8
NOD diabetic mice	NA†	40.3  ±  6.8	NA†	39.5  ±  3.7
NOD-scid	12.1  ±  3.2‡	67.5  ±  12.3	13.6  ±  2.2‡	67.0  ±  4.7

^*All values expressed as the mean ± standard error for n = 6 animals/group. The assays were performed in duplicate on three separate occasions. 

^†NA, not available due to the later age of diabetes onset in the University of Florida NOD colony. 

^‡n = 2.