Interleukin-9 enhances interleukin-5 receptor expression, differentiation, and survival of human eosinophils

• Published in: Blood Vol. 96; no. 6; pp. 2163 - 2171
• Main Authors: Gounni, Abdelilah Soussi, Gregory, Bernard, Nutku, Esra, Aris, Fadi, Latifa, Koussih, Minshall, Eleanor, North, Janet, Tavernier, Jan, Levit, Roy, Nicolaides, Nick, Robinson, Douglas, Hamid, Qutayba
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 15.09.2000; The Americain Society of Hematology
• Subjects: Allergic diseases; Antigens, CD34; Biological and medical sciences; Cell Differentiation - drug effects; Cell Survival - drug effects; Eosinophils - cytology; Eosinophils - drug effects; Eosinophils - metabolism; General aspects; Hematopoietic Stem Cells - cytology; HL-60 Cells; Humans; Immunopathology; Interleukin-9 - pharmacology; Medical sciences; Receptors, Interleukin - biosynthesis; Receptors, Interleukin-5; RNA, Messenger - analysis; Human; Respiratory tract; Immunopathology; Allergy; Interleukin 5; Pathogenesis; Cytokine; Granulocyte; Cell differentiation; Eosinophil; Interleukin 9; Biological receptor
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V96.6.2163

Interleukin-9 (IL-9) has been implicated in the pathogenesis of allergic disorders. To examine the interaction between IL-9 and eosinophils, we evaluated mature peripheral blood eosinophils for their expression of the specific α-subunit of the IL-9 receptor (IL-9R–α). The expression of IL-9R–α by human eosinophils was detected at the messenger RNA (mRNA) and protein levels by reverse transcriptase–polymerase chain reaction (RT-PCR), flow cytometry, and immunocytochemical analysis, respectively. Functional analyses demonstrated that recombinant human (rh)IL-9 inhibited in vitro peripheral blood human eosinophil apoptosis in a concentration-dependent manner. We then examined the role of IL-9 in eosinophil differentiation using the human cord blood CD34+cells and human promyelocytic leukemia cells (HL-60). The addition of IL-9 to CD34+ cells cultured in IL-3 and IL-5 enhanced eosinophil development, and IL-9 alone induced the expression of IL-5R–α. IL-9 also up-regulated the IL-5R–α chain cell surface expression during terminal eosinophil differentiation of the HL-60 cell line. Our findings suggest that IL-9 may potentiate in vivo eosinophil function by increasing their survival and IL-5–mediated differentiation and maturation. Taken together, these results suggest a mechanism by which IL-9 potentiates airway and tissue eosinophilia.