Cytokine-stimulated human lung alveolar epithelial cells release eotaxin-2 (CCL24) and eotaxin-3 (CCL26).
Asthma is a complex inflammatory disease characterized by a prolonged underlying airway inflammation resulting from cytokine-orchestrated signaling between many types of cells, including airway epithelial cells. Trafficking, recruitment, and activation of cells in airway disease are, in part, modulated by the newly discovered CC subfamily of chemokines, eotaxin (CCL11), eotaxin-2 (CCL24) and eotaxin-3 (CCL26), which transduce signals by acting as agonists for the CCR3 receptor. The specific cytokine stimuli that modulate CCL24 and CCL26 release in airway epithelial cells remain poorly defined. Thus, human 549 alveolar type II epithelium-like cells were stimulated singly and with combinations of 1-100 ng/ml tumor necrosis-factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-4, cytokines known to be elevated in the airways of asthmatics. Release of CCL11, CCL24, and CCL26 was quantified by ELISA, and CCR3 receptors monitored by immunocytochemistry and FACS analysis. Results suggest that epithelial cells release CCL11 during the first 24 h of stimulation, in contrast to a significant increase in CCL24 and CCL26 release after 24-48 h of stimulation. Differential release of the eotaxins in response to cytokine combinations was noted. The alveolar type II epithelial cells were found to possess constitutive CCR3 receptors, which increased after proinflammatory cytokine stimulation. The airway epithelium CCR3 receptor/eotaxin ligand signal transduction system may be an important target for development of novel mechanism-based adjunctive therapies designed to interrupt the underlying chronic inflammation in allergic and inflammatory disorders.
Heiman
Ann S
AS
College of Pharmacy and Pharmaceutical Sciences, Florida A & M University, Tallahassee, FL 32307, USA. ann.heiman@famu.edu
Abonyo
Barack O
BO
Darling-Reed
Selina F
SF
Alexander
Marilyn S
MS
D002460:Cell Line; D054423:Chemokine CCL24; D000075906:Chemokine CCL26; D019742:Chemokines, CC / Q000378:metabolism*; D002631:Chemotactic Factors, Eosinophil / Q000378:metabolism; D016207:Cytokines / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D004804:Eosinophils / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D007375:Interleukin-1 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D008168:Lung / Q000166:cytology / Q000378:metabolism*; D054397:Receptors, CCR3; D019707:Receptors, Chemokine / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
C515484:CCL24 protein, human; C120429:CCL26 protein, human; C515350:CCR3 protein, human; D054423:Chemokine CCL24; D000075906:Chemokine CCL26; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil; D016207:Cytokines; D007375:Interleukin-1; D054397:Receptors, CCR3; D019707:Receptors, Chemokine; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4