T-cell Abnormalities Are Present at High Frequencies in Patients With Hypereosinophilic Syndrome

Haematologica. 2009 Sep;94(9):1236-41. doi: 10.3324/haematol.2008.005447.

Abstract

Background: A T-cell clone, thought to be the source of eosinophilopoietic cytokines, identified by clonal rearrangement of the T-cell receptor and by the presence of aberrant T-cell immunophenotype in peripheral blood defines lymphocytic variant of hypereosinophilic syndrome (L-HES).

Design and methods: Peripheral blood samples from 42 patients who satisfied the diagnostic criteria for HES were studied for T-cell receptor clonal rearrangement by polymerase chain reaction according to BIOMED-2. The T-cell immunophenotype population was assessed in peripheral blood by flow cytometry. The FIP1L1-PDGFRA fusion gene was detected by nested polymerase chain reaction.

Results: Forty-two HES patients (18 males and 24 females) with a median age at diagnosis of 56 years (range 17-84) were examined in this study. Their median white blood cell count was 12.9 x 10(9)/L (range 5.3-121), with an absolute eosinophil count of 4.5 x 10(9)/L (range 1.5-99) and a median eosinophilic bone marrow infiltration of 30% (range 11-64). Among the 42 patients, clonal T-cell receptor rearrangements were detected in 18 patients (42.8%). Patients with T-cell receptor clonality included: T-cell receptor beta in 15 patients (35%), T-cell receptor gamma in 9 (21%) and T-cell receptor delta in 9 (21%) patients, respectively. Clonality was detected in all three T-cell receptor loci in 4 cases, in two loci in 7 patients and in one T-cell receptor locus in the remaining 7 patients. The FIP1L1-PDGFRA fusion transcript was absent in all but 2 patients with T-cell receptor clonality. Three patients out of 42 revealed an aberrant T-cell immunophenotype. In some patients, an abnormal CD4:CD8 ratio was demonstrated.

Conclusions: T-cell abnormalities are present at high frequencies in patients with HES.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • CD4-CD8 Ratio
  • Female
  • Gene Rearrangement, beta-Chain T-Cell Antigen Receptor / genetics
  • Gene Rearrangement, beta-Chain T-Cell Antigen Receptor / immunology*
  • Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor / genetics
  • Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor / immunology*
  • Humans
  • Hypereosinophilic Syndrome / blood
  • Hypereosinophilic Syndrome / genetics
  • Hypereosinophilic Syndrome / immunology*
  • Male
  • Middle Aged
  • Oncogene Proteins, Fusion / biosynthesis
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / immunology*
  • Polymerase Chain Reaction
  • Prospective Studies
  • Receptor, Platelet-Derived Growth Factor alpha / biosynthesis
  • Receptor, Platelet-Derived Growth Factor alpha / genetics
  • Receptor, Platelet-Derived Growth Factor alpha / immunology*
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / pathology
  • mRNA Cleavage and Polyadenylation Factors / biosynthesis
  • mRNA Cleavage and Polyadenylation Factors / genetics
  • mRNA Cleavage and Polyadenylation Factors / immunology*

Substances

  • Oncogene Proteins, Fusion
  • mRNA Cleavage and Polyadenylation Factors
  • FIP1L1-PDGFRA fusion protein, human
  • Receptor, Platelet-Derived Growth Factor alpha