title: A functional gammadeltaTCR/CD3 complex distinct from gammadeltaT cells is expressed by human eosinophils.
abstract: BACKGROUND
  Eosinophils are effector cells during parasitic infections and allergic responses. However, their contribution to innate immunity has been only recently unravelled.
  
  
  RESULTS
  Here we show that human eosinophils express CD3 and gammadelta T Cell Receptor (TCR) but not alphabeta TCR. Surface expression of gammadeltaTCR/CD3 is heterogeneous between eosinophil donors and inducible by mycobacterial ligands. Surface immunoprecipitation revealed expression of the full gammadeltaTCR/CD3 complex. Real-time PCR amplification for CD3, gamma and delta TCR constant regions transcripts showed a significantly lower expression in eosinophils than in gammadeltaT cells. Limited TCR rearrangements occur in eosinophils as shown by spectratyping analysis of CDR3 length profiles and in situ hybridization. Release by eosinophils of Reactive Oxygen Species, granule proteins, Eosinophil Peroxidase and Eosinophil-Derived Neurotoxin and cytokines (IFN-gamma and TNF-alpha) was observed following activation by gammadeltaTCR-specific agonists or by mycobacteria. These effects were inhibited by anti-gammadeltaTCR blocking antibodies and antagonists. Moreover, gammadeltaTCR/CD3 was involved in eosinophil cytotoxicity against tumor cells.
  
  
  CONCLUSIONS
  Our results provide evidence that human eosinophils express a functional gammadeltaTCR/CD3 with similar, but not identical, characteristics to gammadeltaTCR from gammadeltaT cells. We propose that this receptor contributes to eosinophil innate responses against mycobacteria and tumors and may represent an additional link between lymphoid and myeloid lineages.
authors.affiliation: Inserm U547, Lille, France.
authors.forename: Fanny
authors.initials: F
authors.lastname: Legrand
authors.forename: Virginie
authors.initials: V
authors.lastname: Driss
authors.forename: Gaëtane
authors.initials: G
authors.lastname: Woerly
authors.forename: Sylvie
authors.initials: S
authors.lastname: Loiseau
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Hermann
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Fournié
authors.forename: Laurent
authors.initials: L
authors.lastname: Héliot
authors.forename: Virginie
authors.initials: V
authors.lastname: Mattot
authors.forename: Fabrice
authors.initials: F
authors.lastname: Soncin
authors.forename: Marie-Lise
authors.initials: ML
authors.lastname: Gougeon
authors.forename: David
authors.initials: D
authors.lastname: Dombrowicz
authors.forename: Monique
authors.initials: M
authors.lastname: Capron
mesh_terms: D017252:CD3 Complex / Q000096:biosynthesis*; D047209:Eosinophil Peroxidase / Q000378:metabolism; D047208:Eosinophil-Derived Neurotoxin / Q000378:metabolism; D004804:Eosinophils / Q000378:metabolism* / Q000382:microbiology; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D009163:Mycobacterium bovis / Q000378:metabolism; D017382:Reactive Oxygen Species; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013499:Surface Properties; D013601:T-Lymphocytes / Q000166:cytology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D017252:CD3 Complex; D017382:Reactive Oxygen Species; D016692:Receptors, Antigen, T-Cell, gamma-delta; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D047209:Eosinophil Peroxidase; D047208:Eosinophil-Derived Neurotoxin