An adjuvant to remember

A team from The Rockefeller University has borrowed a leaf from bispecific T cell engagers to create a strategy for engaging B cells to enhance responses to the seasonal flu vaccine. The group created a bispecific antibody that binds epitopes on influenza A virus hemagglutinin with one part of the molecule, and CD23-expressing B cells with another, and proposes it as an adjuvant for boosting the standard vaccine.

The principle is the same as for bispecific T cell engagers, using different domains of a single molecule to bind a target and to hook an immune cell. But the structure of the molecule is different: whereas the T cell engagers use two single chain mAbs linked together, this molecule consists of a complete antibody in which the Fab domains recognize the antigen, and a sialylated Fc domain engages the CD23 protein on B cells...