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Showing posts from May, 2019

Why Is It Difficult For Antibodies to Fight AIDS?

The primary target for HIV is the ENV glycoprotein. This head protein interacts with the T-cell receptor CD4 which is how HIV enters its target cell.

As a glycoprotein, it has numerous sugars on the outside surface. Those sugars protect the head protein. ENV itself is broken up into two portions, the GP120 and the GP41 domains. The bottom figure shows the sequence conservation of the GP120 protein. In green are the sugars. In white are the conserved domains and in purple are the more variable domains. As it can be seen, when the protein is in its closed state, the headgroup is protected by sugars. The exposed protein domains are the most variable portions of the protein.