A functional study on CysLT1 receptors in human eosinophils

Nobuharu Ohshima, Hiroyuki Nagase, Takeshi Koshino, Misato Miyamasu, Masao Yamaguchi, Koichi Hirai, Kazuhiko Yamamoto, Takao Fujisawa, Naoki Nakagawa, Katsuya Kishikawa, Yutaka Morita

Research output: Contribution to journalArticlepeer-review

29 Citations (Scopus)

Abstract

Background: The cysteinyl leukotrienes (CysLTs) mediate their biological actions through two receptors: CysLT1 receptor and CysLT2 receptor. Objective: This study was undertaken to examine the direct effects of CysLTs on eosinophils, such as chemotaxis and degranulation, focusing on CysLT1. Methods: Eosinophils were isolated from venous blood from normal volunteers who had no history of allergy (purity >99%). They were subjected to reverse transcription-PCR analysis and flow-cytometric analysis for CysLT1. Binding assays were performed with [3H]LTD4. Purified eosinophils loaded with Fura-2 acetoxymethyl ester were stimulated with CysLTs, and Ca2+ influx was measured. Eosinophil migration in response to CysLTs was measured using a 96-well multi-well Boyden chamber. Eosinophils were treated with LTD4 at 10-6 M for 60 min followed by incubation for 4 h at 37°C in the presence or absence of IL-5 and eosinophil-derived neurotoxin (EDN) release was evaluated. Results: The expression of the mRNA and protein of CysLT1 on eosinophils and [3H]LTD4-specific binding to eosinophils were observed. Neither Th1 cytokine (IFN-γ) nor Th2 cytokines (IL-4 or IL-5) affected CysLT1 expression in eosinophils. CysLTs induced an increase in intracellular free Ca2+ in eosinophils via CysLT1, as suggested by the efficient inhibition by a CysLT1 antagonist, pranlukast, in addition to the rank order of potency being LTD4, LTC4 and LTE4. LTD4 stimulated eosinophils to migrate at 10-6 M via CysLT1. LTE4 also induced significant eosinophil migration at 10-6 M. LTD4 enhanced EDN release induced by IL-5 via CysLT1. Conclusion: CysLTs induce migration and enhance degranulation in eosinophils via CysLT1. Accordingly, interaction of CysLTs and CysLT1 on eosinophils has the potential to play a prominent role in the pathophysiology of asthma.

Original languageEnglish
Pages (from-to)67-75
Number of pages9
JournalInternational archives of allergy and immunology
Volume129
Issue number1
DOIs
Publication statusPublished - 2002

Keywords

  • Bronchial asthma
  • Cainflux
  • CysLT receptor
  • Cysteinyl leukotrienes
  • Eosinophil
  • Eosinophil-derived neurotoxin
  • IL-5
  • Migration

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'A functional study on CysLT<sub>1</sub> receptors in human eosinophils'. Together they form a unique fingerprint.

Cite this