Allergen-Specific Immunotherapy Alters the Frequency, as well as the FcR and CLR Expression Profiles of Human Dendritic Cell Subsets

PLoS One. 2016 Feb 10;11(2):e0148838. doi: 10.1371/journal.pone.0148838. eCollection 2016.

Abstract

Allergen-specific immunotherapy (AIT) induces tolerance and shifts the Th2 response towards a regulatory T-cell profile. The underlying mechanisms are not fully understood, but dendritic cells (DC) play a vital role as key regulators of T-cell responses. DCs interact with allergens via Fc receptors (FcRs) and via certain C-type lectin receptors (CLRs), including CD209/DC-SIGN, CD206/MR and Dectin-2/CLEC6A. In this study, the effect of AIT on the frequencies as well as the FcR and CLR expression profiles of human DC subsets was assessed. PBMC was isolated from peripheral blood from seven allergic donors before and after 8 weeks and 1 year of subcutaneous AIT, as well as from six non-allergic individuals. Cells were stained with antibodies against DC subset-specific markers and a panel of FcRs and CLRs and analyzed by flow cytometry. After 1 year of AIT, the frequency of CD123+ DCs was increased and a larger proportion expressed FcεRI. Furthermore, the expression of CD206 and Dectin-2 was reduced on CD141+ DCs after 1 year of treatment and CD206 as well as Dectin-1 was additionally down regulated in CD1c+ DCs. Interestingly, levels of DNGR1/CLEC9A on CD141+ DCs were increased by AIT, reaching levels similar to cells isolated from non-allergic controls. The modifications in phenotype and occurrence of specific DC subsets observed during AIT suggest an altered capacity of DC subsets to interact with allergens, which can be part of the mechanisms by which AIT induces allergen tolerance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Allergens / administration & dosage
  • Allergens / immunology*
  • Antibody Specificity
  • Antigen Presentation
  • Antigens, Surface / analysis
  • Cell Count
  • Dendritic Cells / classification
  • Dendritic Cells / immunology*
  • Dendritic Cells / metabolism
  • Desensitization, Immunologic*
  • Female
  • Flow Cytometry
  • Gene Expression Regulation / immunology
  • Humans
  • Immune Tolerance
  • Immunoglobulin E / blood
  • Immunoglobulin G / blood
  • Immunophenotyping
  • Interleukin-3 Receptor alpha Subunit / analysis
  • Lectins, C-Type / biosynthesis*
  • Lectins, C-Type / genetics
  • Male
  • Receptors, Fc / biosynthesis*
  • Receptors, Fc / genetics
  • Thrombomodulin
  • Young Adult

Substances

  • Allergens
  • Antigens, Surface
  • IL3RA protein, human
  • Immunoglobulin G
  • Interleukin-3 Receptor alpha Subunit
  • Lectins, C-Type
  • Receptors, Fc
  • THBD protein, human
  • Thrombomodulin
  • Immunoglobulin E

Grants and funding

This study was funded by grants from Signhild Engkvist foundation, Faculty of Engineering (LTH), Skåne County Council Research Foundation and Lund University Research Foundation (ALF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.