Antiviral lectins as potential HIV microbicides

• Lectins are potential antivirals.
• The structural basis for the anti-HIV activity of various lectins is reviewed.
• The atomic structures of several lectins as well as their sugar binding specificities are described.

A growing class of potential antivirals encompasses carbohydrate-binding proteins, such as antibodies and lectins. They block virus entry into host target cells and halt virus transmission from virus-infected cells to non-infected cells, thereby preventing infection. Here, we review the structural basis for the anti-HIV activity of various lectins, describing their structures and determinants of high-affinity oligosaccharide binding. The mechanism of glycan recognition on the gp120 envelope protein by these antiviral lectins may therefore be exploited for developing agents and alternative strategies to prevent HIV transmission.