FIG 2.
MAb N12-i15 defines a CD4i region upon gp120 distinct from the bridging sheet. Competition ELISAs were carried out in order to discern whether all the detected CD4i epitopes cluster to one area on gp120 or not. Binding of CD4i MAbs to gp120BaL-sCD4 was measured in either the absence or the presence of prebound MAb CG10. MAbs 17b, 21c, and 19e compete strongly with MAb CG10. MAb N12-i15 defines a CD4i epitope sufficiently separated from the bridging sheet so as to show no competition with MAb CG10. Statistically significant differences (P < 0.05) between the “−CG10” and “+CG10” columns are marked with an asterisk.