Stability of the sCD4-activated intermediate form of the HIV-1 envelope glycoproteins.Conformational Stability of the CD4-Activated IntermediateEngagement of CD4 induces a major structural rearrangement of the HIV-1 envelope glycoproteins [2]. Two functionally important regions of the HIV-1 envelope glycoproteins are formed and exposed as a result of CD4 binding: i) the coreceptor-binding site on