Charcot-Leyden crystal protein/galectin-10 interacts with cationic ribonucleases and is required for eosinophil granulogenesis.
J Allergy Clin Immunol
; 146(2): 377-389.e10, 2020 08.
Article
en En
| MEDLINE
| ID: mdl-31982451
ABSTRACT
BACKGROUND:
The human eosinophil Charcot-Leyden crystal (CLC) protein is a member of the Galectin superfamily and is also known as galectin-10 (Gal-10). CLC/Gal-10 forms the distinctive hexagonal bipyramidal crystals that are considered hallmarks of eosinophil participation in allergic responses and related inflammatory reactions; however, the glycan-containing ligands of CLC/Gal-10, its cellular function(s), and its role(s) in allergic diseases are unknown.OBJECTIVE:
We sought to determine the binding partners of CLC/Gal-10 and elucidate its role in eosinophil biology.METHODS:
Intracellular binding partners were determined by ligand blotting with CLC/Gal-10, followed by coimmunoprecipitation and coaffinity purifications. The role of CLC/Gal-10 in eosinophil function was determined by using enzyme activity assays, confocal microscopy, and short hairpin RNA knockout of CLC/Gal-10 expression in human CD34+ cord blood hematopoietic progenitors differentiated to eosinophils.RESULTS:
CLC/Gal-10 interacts with both human eosinophil granule cationic ribonucleases (RNases), namely, eosinophil-derived neurotoxin (RNS2) and eosinophil cationic protein (RNS3), and with murine eosinophil-associated RNases. The interaction is independent of glycosylation and is not inhibitory toward endoRNase activity. Activation of eosinophils with INF-γ induces the rapid colocalization of CLC/Gal-10 with eosinophil-derived neurotoxin/RNS2 and CD63. Short hairpin RNA knockdown of CLC/Gal-10 in human cord blood-derived CD34+ progenitor cells impairs eosinophil granulogenesis.CONCLUSIONS:
CLC/Gal-10 functions as a carrier for the sequestration and vesicular transport of the potent eosinophil granule cationic RNases during both differentiation and degranulation, enabling their intracellular packaging and extracellular functions in allergic inflammation.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Células Madre Hematopoyéticas
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Glicoproteínas
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Gránulos Citoplasmáticos
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Proteína Catiónica del Eosinófilo
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Neurotoxina Derivada del Eosinófilo
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Eosinófilos
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Granuloma
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Hipersensibilidad
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Lisofosfolipasa
Límite:
Animals
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Humans
Idioma:
En
Revista:
J Allergy Clin Immunol
Año:
2020
Tipo del documento:
Article