A modified polypeptide corresponding to an envelope glycoprotein of a primate
lentivirus
is described. The polypeptide has been modified from the wild-type structure so
that it has at least two of the glycosylation sites proximal to the CD4 binding
site or chemokine receptor site altered so that the alteration prevents glycosylation
at that site or where glycosylation sites distal to these sites have been derivatized
with a molecular adjuvant, while retaining the overall 3-dimensional structure
of a discontinuous conserved epitope of the wild-type protein. Preferably, the
polypeptide has both changes. Preferably, the primate lentivirus is HIV, and the
protein is HIV-1 gp 120.
