ABSTRACT DC-SIGN, a type II membrane protein with a C-type lectin binding domain that is
highly expressed on mucosal dendritic cells (DCs) and certain macrophages in vivo, binds
to ICAM-3, ICAM-2, and human and simian immunodeficiency viruses (HIV and SIV). Virus
captured by DC-SIGN can be presented to T cells, resulting in efficient virus infection,
perhaps representing a mechanism by which virus can be ferried via normal DC trafficking
from mucosal tissues to lymphoid organs in vivo. To develop reagents needed to …

MATERIALS AND METHODS Cells, antibodies, and reagents. 293T cells were used for
transient-transfection experiments. To obtain DCs from peripheral blood mononuclear cells
(PBMC), we used the method originally described by Sallusto et al. with minor modifications
(16, 21). Brieffy, monocytes were purified from PBMC by discontinuous Percoll gradient
centrifugation. The low-density fraction (monocyte enriched) was depleted of B, T, and, in
certain experiments, NK cells by using magnetic beads (Dynal, Lake Success, NY) specific …