The env proteins of retroviruses play critical roles in viral infection and function, and are major targets of the immune response to viral infection. Our group is investigating the roles of retroviral env proteins in viral function and pathogenesis. One area of research involves the identification characterization of epitopes in HIV gp120 and gp41 recognized by antibodies with potent neutralizing activities, and the development of new approaches towards effective vaccines against HIV-1. These approaches include a novel recombinant fusion glycoprotein system developed in our lab which we are using to express isolated sub-domains of the HIV-1 Envelope protein in native form. These protein fragments are being used for structural studies, and to examine the contribution of the individual domains towards the protective humoral response against HIV-1.

A second area of research involves the analysis of structure and function of the env proteins of murine leukemia viruses (MuLV). These studies include elucidation of the roles of specific domains of these proteins in viral infection and leukemogenesis, and the development of modified MuLV envs that can be used to redirect viral tropism. Such viruses could find uses as gene therapy vectors and as anti-viral and anti-tumor reagents. A related line of research is aimed at the development of a selectable retroviral surface display system suitable for the expression of glycoprotein and glycopeptide libraries. This system could have applications both in vaccine development and as a general method for identifying novel glycopeptide ligands.