TABLE 1.

Neutralization of clone R2-, MN-TCLA-, and MN-P-pseudotyped viruses by MAbs and sCD4a

Envelope regionAntibody and/or ligandEpitopeIC50 (μg/ml) for strain
R2MN-TCLAMN-P
V3257D-IVRIHIG>0.50.01b
268D-IVHIGPGR>0.50.05
IIIB/V3-13IRIQRGPGR>10
IIIB/V3-21INCTRPN>10
R/V3-50-1RIHIG>10≤0.01
19bXIXXXXGXXFYXT1.71.010.0
391/95DKRIHIGPGRAFY>100.01
418-DHIGPGRA>10
694/98-DGRAF2.50.01>20
447-52DGPGR>10<0.05
838-DKISITK>10
1027-DKISITKGP>10
CD4bsF105Conformational>10>100
15eConformational3.71.2>20
IgG1B12Conformational6.60.021.3
sCD4CD4bs0.280.115.2
CD4i4.8DConformational8.61.0>20
17bConformational9.45.0
gp412F5ELDKWA7.55.0
Other2G12Unknown7.5>50
  • a The sources of the antibodies and sCD4 are indicated in Materials and Methods. The neutralizing concentrations are the 50% neutralizing endpoints, calculated as described elsewhere (43, 52). Results are averages of duplicate experiments.

  • b —, no test was done.