Nerve growth factor is preformed in and activates human peripheral blood eosinophils

J Allergy Clin Immunol. 1998 Sep;102(3):454-60. doi: 10.1016/s0091-6749(98)70135-6.

Abstract

Background: Recent studies have shown that nerve growth factor (NGF) is produced by and can act on several immune-inflammatory cells.

Objectives: The objective of this study was to study the effects of NGF on human peripheral blood eosinophils and assess whether these cells produce and store NGF.

Methods: Eosinophils were purified by negative immunoselection (magnetic cell sorting systems, purity 98% to 100%) from 13 subjects (9 to 26 years old) with mild blood eosinophilia, mainly of allergic origin. Eosinophils were incubated with NGF (50 to 1000 ng/mL), and supernatants were collected for measurement of eosinophil peroxidase (EPO, 20 minutes, colorimetric enzymatic assay) and IL-6 (12 hours, ELISA). Eosinophil viability was evaluated by Trypan blue test (days 2, 3, and 4). NGF content in freshly isolated eosinophils, after ultrasound disruption, was determined with a 2-site immunoenzymatic assay. The presence of mRNA for NGF was evaluated by reverse transcription PCR.

Results: NGF caused EPO release (highly significant at 1000 ng/mL NGF). IL-6 release from eosinophils was not higher than IL-6 spontaneously released into culture medium alone. NGF did not significantly affect the number of viable eosinophils. NGF was found in the eosinophil sonicates (1.5 to 17.8 pg/mL per 106 cells). Similarly, mRNA for NGF was detected by reverse transcription PCR in the freshly isolated eosinophils.

Conclusions: NGF activates human peripheral blood eosinophils from subjects with mild eosinophilia to selectively release inflammatory mediators. Eosinophils store and produce NGF. Therefore the capability of NGF to induce a secretory response and its production and storage by circulating human eosinophils suggest a possible role for NGF in conditions associated with eosinophilia, including allergic disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Cell Survival / drug effects
  • Child
  • Eosinophil Peroxidase
  • Eosinophilia / blood
  • Eosinophilia / immunology
  • Eosinophils / drug effects*
  • Eosinophils / metabolism
  • Eosinophils / physiology*
  • Humans
  • Hypersensitivity / blood
  • Interleukin-6 / metabolism
  • Nerve Growth Factors / biosynthesis*
  • Nerve Growth Factors / pharmacology*
  • Nerve Growth Factors / physiology
  • Peroxidases / blood
  • RNA, Messenger / metabolism

Substances

  • Interleukin-6
  • Nerve Growth Factors
  • RNA, Messenger
  • Eosinophil Peroxidase
  • Peroxidases