An assay for functional dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) inhibitors of human dendritic cell adhesion.

We report a new dendritic cell adhesion assay, using either immature or mature dendritic cells, for identifying functional dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) inhibitors. Because immature dendritic cells are responsible for pathogen binding and invasion, this in vitro assay provides an important link between in vitro results and pathogen-based in vivo assays. Furthermore, this assay does not require laborious expression, refolding, and purification of DC-SIGN carbohydrate recognition domain or extracellular domain as receptor-based assays. The assay power evaluated with Z and Z' parameters enables screening of compound libraries and determination of IC(50) values in the first stage of DC-SIGN inhibitor development.