TABLE 1.

Native but not reduced human CD81 LEL protein binds E2₆₆₁, while anti-CD81 MAb 1D6 binds a defined reduced peptide within the LEL

Peptide	Human CD81 amino acids	DTTa	Binding of E2661	Binding of 1D6 (μg/ml)
				1.0	0.2	0.04	0.008
1041	133–201	+		1.35	0.72	0.26	0.17
1095	155–201	+	0.03	1.42	1.34	1.04	0.60
1101	164–201	+	0.21	1.45	1.30	0.87	0.41
1143	164–192	+	0.03	1.07	0.41	0.10	0.05
1144	173–192	+	0.02	1.25	0.48	0.30	0.05
1108	179–193	+	0.02	0.51	0.08	0.06	0.03
1077	146–155	+	0.03	0.05	0.05	0.02	0.03
1084	156–164	+	0.04	0.03	0.04	0.04	0.02
GST-human CD81	LEL	−	2.48	1.58	1.29	0.97	0.41
		+	0.22	1.74	1.21	0.94	0.61
GST-mouse CD81	LEL	−	0.05	0.03	0.05	0.05	0.04
		+	0.03	0.03	0.01	0.03	0.03

^aPeptides (10 mM) and proteins were incubated in PBS-dithiothreitol (DTT) (0.1 M) for 30 min at RT prior to coating of the ELISA plate.