TABLE 1.

N36^Mut(e,g) and neutralizing gp41-directed MAbs inhibit infectivity synergistically in an HBX2 Env-pseudotyped virus neutralization assay^a

Ab peptide	Ab/N36Mut(e,g) combination ratio	DRI (mean ± SD)		CI (mean ± SD)
		Ab	N36Mut(e,g)
bF-3674b	1:20	2.4 ± 0.6	7.4 ± 1.6	0.6 ± 0.2
	1:40	4.0 ± 0.9	6.4 ± 1.2	0.4 ± 0.2
	1:80	7.0 ± 1.5	5.6 ± 0.9	0.3 ± 0.1
	1:100	10.0 ± 2.7	6.4 ± 1.5	0.3 ± 0.1
	1:200	10.4 ± 2.3	3.3 ± 0.6	0.4 ± 0.1
mF-3674b	1:10	3.7 ± 1.0	3.5 ± 0.8	0.6 ± 0.2
	1:20	11.8 ± 2.4	5.5 ± 0.9	0.3 ± 0.1
2F5	1:500	3.4 ± 1.0	8.4 ± 1.6	0.4 ± 0.2
	1:1,000	8.2 ± 1.9	9.7 ± 1.2	0.2 ± 0.1
4E10	1:500	6.2 ± 1.5	12.7 ± 2.7	0.3 ± 0.1
	1:1,000	12.0 ± 2.6	12.1 ± 2.2	0.2 ± 0.1

^aThe IC₅₀s of the antibodies alone are as follows: bF-3674, 88 ± 14 nM; mf-3674, 603 ± 91 nM; 2F5, 3.8 ± 1.0 nM; 4E10, 6.3 ± 3.7 nM. The IC₅₀ for N36^Mut(e,g) is 5.7 ± 0.5 μM.

^bbF-3674 and mF-3674 are the bivalent and monovalent versions of Fab 3674, respectively (16).