Expression of Multilectin Receptors and Comparative FITC-dextran Uptake by Human Dendritic Cells

Int Immunol. 2000 Nov;12(11):1511-9. doi: 10.1093/intimm/12.11.1511.

Abstract

Dendritic cells (DC) are potent antigen-presenting cells and understanding their mechanisms of antigen uptake is important for loading DC with antigen for immunotherapy. The multilectin receptors, DEC-205 and macrophage mannose receptor (MMR), are potential antigen-uptake receptors; therefore, we examined their expression and FITC-dextran uptake by various human DC preparations. The RT-PCR analysis detected low levels of DEC-205 mRNA in immature blood DC, Langerhans cells (LC) and immature monocyte-derived DC (Mo-DC). Its mRNA expression increased markedly upon activation, indicating that DEC-205 is an activation-associated molecule. In Mo-DC, the expression of cell-surface DEC-205 increased markedly during maturation. In blood DC, however, the cell-surface expression of DEC-205 did not change during activation, suggesting the presence of a large intracellular pool of DEC-205 or post-transcriptional regulation. Immature Mo-DC expressed abundant MMR, but its expression diminished upon maturation. Blood DC and LC did not express detectable levels of the MMR. FITC-dextran uptake by both immature and activated blood DC was 30- to 70-fold less than that of LC, immature Mo-DC and macrophages. In contrast to immature Mo-DC, the FITC-dextran uptake by LC was not inhibited effectively by mannose, an inhibitor for MMR-mediated FITC-dextran uptake. Thus, unlike Mo-DC, blood DC and LC do not use the MMR for carbohydrate-conjugated antigen uptake and alternative receptors may yet be defined on these DC. Therefore, DEC-205 may have a different specificity as an antigen uptake receptor or contribute to an alternative DC function.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD*
  • COS Cells
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism*
  • Dextrans / metabolism*
  • Fluorescein-5-isothiocyanate / analogs & derivatives*
  • Fluorescein-5-isothiocyanate / metabolism*
  • Fluorescent Dyes / metabolism
  • Hodgkin Disease / metabolism
  • Humans
  • Isoquinolines / metabolism
  • Langerhans Cells / immunology
  • Langerhans Cells / metabolism
  • Lectins / metabolism
  • Lectins, C-Type*
  • Macrophages / immunology
  • Macrophages / metabolism
  • Mannose-Binding Lectins*
  • Membrane Glycoproteins / biosynthesis*
  • Membrane Glycoproteins / blood
  • Membrane Glycoproteins / genetics
  • Minor Histocompatibility Antigens
  • Monocytes / immunology
  • Monocytes / metabolism
  • Pinocytosis / immunology
  • RNA, Messenger / biosynthesis
  • Receptors, Antigen / biosynthesis*
  • Receptors, Cell Surface / biosynthesis*
  • Receptors, Cell Surface / blood
  • Receptors, Cell Surface / genetics
  • Tumor Cells, Cultured

Substances

  • Antigens, CD
  • DEC-205 receptor
  • Dextrans
  • Fluorescent Dyes
  • Isoquinolines
  • Lectins
  • Lectins, C-Type
  • Mannose-Binding Lectins
  • Membrane Glycoproteins
  • Minor Histocompatibility Antigens
  • RNA, Messenger
  • Receptors, Antigen
  • Receptors, Cell Surface
  • fluorescein isothiocyanate dextran
  • mannose receptor
  • lucifer yellow
  • Fluorescein-5-isothiocyanate