A CD91-positive subset of CD11c+ blood dendritic cells: characterization of the APC that functions to enhance adaptive immune responses against CD91-targeted antigens.

Journal Article (Journal Article)

Dendritic cells (DC) and other APCs rely on a number of specialized receptors to facilitate the uptake and intracellular accumulation of Ags. In this capacity, APCs use receptor-mediated endocytosis to enhance Ag presentation and the stimulation of Ag-specific T cells. Studies have demonstrated that the targeted delivery of Ags in vivo to CD91/the low-density lipoprotein receptor-related protein (CD91/LRP) induces enhanced activation of the adaptive immune system. However, the APC that mediates these augmented, Ag-specific responses remains to be characterized. In this study, we show that a subset of CD11c(+) lineage-negative (lin(-)) DC expresses the scavenger receptor CD91/LRP and that these rare APC are primarily responsible for the T cell activation that occurs following CD91/LRP-mediated Ag uptake in whole blood. The targeting of Ags to CD91/LRP results in enhanced receptor-mediated uptake within both lin(-) DCs and monocytes, and this uptake results in markedly increased T cell activation. Finally, purified cellular populations were used to demonstrate that CD11c(+) lin(-) DC, but not monocytes, are capable of stimulating T cell activation following CD91/LRP-mediated Ag uptake. Therefore, CD11c(+) lin(-) DC use CD91/LRP to facilitate the uptake and subsequent presentation of an array of Ags complexed within the CD91/LRP ligand, the activated form of alpha2-macroglobulin (alpha2M*).

Full Text

Duke Authors

Cited Authors

  • Hart, JP; Gunn, MD; Pizzo, SV

Published Date

  • January 1, 2004

Published In

Volume / Issue

  • 172 / 1

Start / End Page

  • 70 - 78

PubMed ID

  • 14688311

International Standard Serial Number (ISSN)

  • 0022-1767

Digital Object Identifier (DOI)

  • 10.4049/jimmunol.172.1.70


  • eng

Conference Location

  • United States