CD4-induced epitope of HIV-1 envelope glycoprotein gp120 (CD4i epitope)

CD4-induced epitopes are *conserved, conformational regions* on the HIV-1 envelope glycoprotein gp120 that become exposed or structurally stabilized after gp120 binds to the host CD4 receptor during viral entry[2][5][4]. These epitopes overlap the *coreceptor (CCR5/CXCR4) binding site* and are recognized by certain broadly neutralizing antibodies, such as 17b, and are of significant interest for HIV vaccine and therapeutic antibody development because they are relatively conserved among diverse HIV strains[2][5][3][4]. However, they are not standalone protein targets but rather *antigenic surfaces* that appear only after a CD4-induced conformational change in gp120 and are not considered canonical therapeutic targets, though they are used as research targets/epitopes in immunology[2][5][6][4]. **Note on "is_incorrect":** This is not a canonical molecular target such as a receptor, enzyme, or transporter, but a conformational *epitome* exposure state. The term "CD4-induced epitope" refers to various regions on gp120 that become accessible or antigenic following CD4 engagement, not to a defined protein, gene, or structured molecule, so it does not fit structured databases of drug targets[5][2][4].

Other names

CD4-induced (CD4i) epitopeCD4-inducible epitopegp120 CD4-induced epitope