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IL ‐5‐stimulated eosinophils adherent to periostin undergo stereotypic morphological changes and ADAM 8‐dependent migration
Author(s) -
Johansson M. W.,
Khanna M.,
Bortnov V.,
Annis D. S.,
Nguyen C. L.,
Mosher D. F.
Publication year - 2017
Publication title -
clinical and experimental allergy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.462
H-Index - 154
eISSN - 1365-2222
pISSN - 0954-7894
DOI - 10.1111/cea.12934
Subject(s) - periostin , microbiology and biotechnology , matricellular protein , eosinophil , chemistry , integrin , disintegrin , metalloproteinase , extracellular matrix , biology , immunology , matrix metalloproteinase , receptor , biochemistry , asthma
Summary Background IL ‐5 causes suspended eosinophils to polarize with filamentous (F)‐actin and granules at one pole and the nucleus in a specialized uropod, the “nucleopod,” which is capped with P‐selectin glycoprotein ligand‐1 ( PSGL ‐1). IL ‐5 enhances eosinophil adhesion and migration on periostin, an extracellular matrix protein upregulated in asthma by type 2 immunity mediators. Objective Determine how the polarized morphology evolves to foster migration of IL ‐5‐stimulated eosinophils on a surface coated with periostin. Methods Blood eosinophils adhering to adsorbed periostin were imaged at different time points by fluorescent microscopy, and migration of eosinophils on periostin was assayed. Results After 10 minutes in the presence of IL ‐5, adherent eosinophils were polarized with PSGL ‐1 at the nucleopod tip and F‐actin distributed diffusely at the opposite end. After 30‐60 minutes, the nucleopod had dissipated such that PSGL ‐1 was localized in a crescent or ring away from the cell periphery, and F‐actin was found in podosome‐like structures. The periostin layer, detected with monoclonal antibody Stiny‐1, shown here to recognize the FAS 1 4 module, was cleared in wide areas around adherent eosinophils. Clearance was attenuated by metalloproteinase inhibitors or antibodies to disintegrin metalloproteinase 8 ( ADAM 8), a major eosinophil metalloproteinase previously implicated in asthma pathogenesis. ADAM 8 was not found in podosome‐like structures, which are associated with proteolytic activity in other cell types. Instead, immunoblotting demonstrated proteoforms of ADAM 8 that lack the cytoplasmic tail in the supernatant. Anti‐ ADAM 8 inhibited migration of IL ‐5‐stimulated eosinophils on periostin. Conclusions and Clinical Relevance Migrating IL ‐5‐activated eosinophils on periostin exhibit loss of nucleopodal features and appearance of prominent podosomes along with clearance of the Stiny‐1 periostin epitope. Migration and epitope clearance are both attenuated by inhibitors of ADAM 8. We propose, therefore, that eosinophils remodel and migrate on periostin‐rich extracellular matrix in the asthmatic airway in an ADAM 8‐dependent manner, making ADAM 8 a possible therapeutic target.