Neutrophils as a novel source of eosinophil cationic protein in IgE-mediated processes.
The production of eosinophil cationic protein (ECP) in IgE-mediated diseases has been associated mainly with eosinophils, although no IgE-dependent ECP release has been observed in these cells. Because there is increasing evidence of neutrophil participation in allergic processes, we have examined whether human neutrophils from allergic patients were able to produce ECP by an IgE-dependent mechanism. After challenge with specific Ags to which the patients were sensitized, ECP release was detected in the culture medium. Furthermore, intracellular protein was detected by flow cytometry, immunofluorescence staining, and Western blotting. Expression at both mRNA and de novo protein synthesis were detected, respectively, by RT-PCR and radiolabeling with (35)S. Ag effect was mimicked by cell treatment with anti-IgE Abs or Abs against FcepsilonRI and galectin-3 (FcepsilonRI>galectin-3), but not against FcepsilonRII. These observations represent a novel view of neutrophils as possible source of ECP in IgE-dependent diseases.
Monteseirín
Javier
J
Servicio Regional de Inmunología y Alergia, Hospital Universitario Virgen Macarena, Sevilla, Spain. fmonteserinm@meditex.es
Vega
Antonio
A
Chacón
Pedro
P
Camacho
M Jesús
MJ
El Bekay
Rajaa
R
Asturias
Juan A
JA
Martínez
Alberto
A
Guardia
Pedro
P
Pérez-Cano
Ramón
R
Conde
José
J
D000485:Allergens / Q000494:pharmacology*; D001249:Asthma / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D047150:Eosinophil Cationic Protein / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D037502:Galectin 3 / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology / Q000378:metabolism* / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D014176:Protein Biosynthesis / Q000187:drug effects / Q000276:immunology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D017455:Receptors, IgE / Q000276:immunology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000485:Allergens; D037502:Galectin 3; D012333:RNA, Messenger; D017455:Receptors, IgE; D007073:Immunoglobulin E; D047150:Eosinophil Cationic Protein; C479220:RNASE3 protein, human