Table 3. Cross-reactivity of commercial anti-human IgA and IgG reagents used in sandwich ELISA assays.

Anti Human serum #1	IgA						IgG
(from DAKO)	1	1.10	1∶100	1∶1,000	1∶10,000	1∶100,000	1	1.10	1∶100	1∶1,000	1∶10,000	1∶100,000
Anti-IgA	2,049±	1,903±	1,733±	646±	154±	67±	1,450±	494±	133±	37±	26±	29±
	32	42	48	37	28	20	45	39	22	21	26	24
Anti-IgG	815±	304±	101±	53±	23±	15±	1,939±	1,991±	1,965±	1,701±	918±	420±
	50	45	25	28	24	21	48	43	37	40	34	47
Anti Human serum #2	IgA						IgG
(from Southern Biotech)	1	1.10	1∶100	1∶1,000	1∶10,000	1∶100,000	1	1.10	1∶100	1∶1,000	1∶10,000	1∶100,000
Anti-IgA	1,947±	1,946±	1,572±	627±	164±	90±	1,449±	469±	120±	37±	21±	33±
	53	48	46	49	36	20	42	47	35	31	24	27
Anti-IgG	809±	301±	105±	40±	20±	10±	1,925±	1,998±	1,893±	1,704±	966±	467±
	45	43	38	30	28	27	46	55	51	48	40	32

Dilutions: 1∶1 = 4 microg/mL; 1∶10 = 400 ng/mL; 1∶10² = 40 ng/mL; 1∶10³ = 4 ng/mL; 1∶10⁴ = 400 pg/mL; 1∶10⁵ = 40 pg/mL. Response variability was also reported in the Table.

Results are expressed in OD values.