Researchers at Caltech have uncovered the structure of clade C gp120 – an HIV surface glycoprotein that interacts with CD4 receptors and is essential for viral entry into cells. HIV-1 clade C is the most rapidly spreading subtype of HIV, infecting millions of people primarily in Africa and Asia.
In order to facilitate the crystallization of gp120, a necessary step in visualizing its structure, the researchers created a complex of molecules consisting of a gp120 monomer, a CD4 receptor, and an anti-HIV antibody known as 21c. One surprising discovery the team made was the polyreactivity of 21c. Antibody 21c was not only reacting to gp120, but also was reacting to the CD4 receptors on the body’s own T cells.
Press release: Caltech Scientists Uncover Structure of Key Protein in Common HIV Subgroup…
Study abstract: Structure of a clade C HIV-1 gp120 bound to CD4 and CD4-induced antibody reveals anti-CD4 polyreactivity