Table 2. Assay specificity^a.

Serum dilution	Signal:Background		Fold change
	−BG-A	+BG-A
1:20,000	5.1	1.5	3.3
1:10,000	18.0	1.2	15.1
1:5,000	39.1	1.5	25.5
1:4,000	47.7	2.4	20.3
1:1,000	197.7	4.6	42.6

^a Assay specificity. When positive serum was pre-incubated with 25mg/mL BG-A, a substantial, dose-dependent decrease in signal is observed.