Amphiregulin production by human eosinophils

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• Amphiregulin (AREG) is crucial for mammary gland development, nematode infection immunity, and lung mucous production.
• Significant eosinophil infiltration is observed at these sites, prompting investigation into eosinophil-derived AREG.

Purpose of the Study:

• To investigate the production and release of amphiregulin (AREG) by human eosinophils in vitro.
• To determine the factors influencing AREG expression and release from eosinophils.

Main Methods:

• Human eosinophils were purified from peripheral blood of normal or mild allergic patients.
• Eosinophils were stimulated with granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-5, IFN-gamma, or secretory IgA.
• AREG mRNA and protein levels were assessed using microarray, RT-PCR, and ELISA.

Main Results:

• Constitutive AREG mRNA expression was found in fresh eosinophils, exceeding levels in other blood cells.
• GM-CSF and IL-5 significantly increased AREG mRNA, while IFN-gamma and IgA did not.
• Dexamethasone enhanced GM-CSF-induced AREG mRNA expression; AREG protein was released upon GM-CSF stimulation.

Conclusions:

• Human eosinophils are a source of AREG production and release.
• Eosinophil-derived AREG likely contributes to physiological and pathological processes in vivo.
• These findings highlight a novel role for eosinophils in immune and developmental contexts.