Fcγ receptor antigen targeting potentiates cross-presentation by human blood and lymphoid tissue BDCA-3+ dendritic cells

Blood. 2012 Dec 20;120(26):5163-72. doi: 10.1182/blood-2012-06-434498. Epub 2012 Oct 23.

Abstract

The reactivation of human cytomegalovirus (HCMV) poses a serious health threat to immune compromised individuals. As a treatment strategy, dendritic cell (DC) vaccination trials are ongoing. Recent work suggests that BDCA-3(+) (CD141(+)) subset DCs may be particularly effective in DC vaccination trials. BDCA-3(+) DCs had however been mostly characterized for their ability to cross-present antigen from necrotic cells. We here describe our study of human BDCA-3(+) DCs in elicitation of HCMV-specific CD8(+) T-cell clones. We show that Fcgamma-receptor (FcγR) antigen targeting facilitates antigen cross-presentation in several DC subsets, including BDCA-3(+) DCs. FcγR antigen targeting stimulates antigen uptake by BDCA-1(+) rather than BDCA-3(+) DCs. Conversely, BDCA-3(+) DCs and not BDCA-1(+) DCs show improved cross-presentation by FcγR targeting, as measured by induced release of IFNγ and TNF by antigen-specific CD8(+) T cells. FcγR-facilitated cross-presentation requires antigen processing in both an acidic endosomal compartment and by the proteasome, and did not induce substantial DC maturation. FcγRII is the most abundantly expressed FcγR on both BDCA-1(+) and BDCA-3(+) DCs. Furthermore we show that BDCA-3(+) DCs express relatively more stimulatory FcγRIIa than inhibitory FcγRIIb in comparison with BDCA-1(+) DCs. These studies support the exploration of FcγR antigen targeting to BDCA-3(+) DCs for human vaccination purposes.

Publication types

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

MeSH terms

  • Antigen Presentation / drug effects
  • Antigen Presentation / physiology
  • Antigens, Surface / metabolism
  • Antigens, Viral / immunology
  • Antigens, Viral / pharmacology*
  • Antigens, Viral / therapeutic use
  • Blood / immunology*
  • Blood / metabolism
  • CD8-Positive T-Lymphocytes / immunology
  • Cells, Cultured
  • Cross-Priming* / drug effects
  • Cross-Priming* / immunology
  • Dendritic Cells / immunology*
  • Dendritic Cells / metabolism
  • Dendritic Cells / physiology
  • Drug Synergism
  • Humans
  • Immunotherapy, Active / methods
  • Immunotherapy, Adoptive / methods
  • Lymphoid Tissue / immunology*
  • Lymphoid Tissue / metabolism
  • Phosphoproteins / immunology
  • Phosphoproteins / pharmacology
  • Receptors, IgG / antagonists & inhibitors
  • Receptors, IgG / immunology*
  • Receptors, IgG / physiology
  • Thrombomodulin
  • Viral Matrix Proteins / immunology
  • Viral Matrix Proteins / pharmacology

Substances

  • Antigens, Surface
  • Antigens, Viral
  • Phosphoproteins
  • Receptors, IgG
  • THBD protein, human
  • Thrombomodulin
  • Viral Matrix Proteins
  • cytomegalovirus matrix protein 65kDa