title: Epidermal keratinocyte-derived basophil promoting activity. Role of interleukin 3 and soluble CD23.
abstract: Human epidermal keratinocytes (EK) secrete factors able to sustain the proliferation of early myeloid cells and, in particular, the generation of basophils. This activity was previously attributed to IL-3, although no definitive in situ demonstration of this cytokine was provided. In regard to the possible physiological relevance of these data, we investigated herein the nature of EK-derived factors responsible for basophil promotion. Our data show that EK-derived supernatants (EK-sup) contain IL-3 as well as soluble CD23 (sCD23), both known for their colony stimulating activity. Messenger RNA for IL-3 and CD23 were also detected in EK. Blocking experiments using specific neutralizing monoclonal antibodies (mAb) further indicate that EK-derived basophil promoting activity is mainly due to the presence of IL-3 and sCD23 in EK-sup. Furthermore, by contrast to IL-3, sCD23 secretion by EK is cortisone sensitive and highly enhanced by IL-4, suggesting distinct regulatory mechanisms for their production.
authors.affiliation: Laboratoire d'Immunologie, Centre National de la Recherche Scientifique URA625, CHU Pitié-Salpêtrière, Paris, France.
authors.forename: A H
authors.initials: AH
authors.lastname: Dalloul
authors.forename: M
authors.initials: M
authors.lastname: Arock
authors.forename: C
authors.initials: C
authors.lastname: Fourcade
authors.forename: J Y
authors.initials: JY
authors.lastname: Béranger
authors.forename: P
authors.initials: P
authors.lastname: Jaffray
authors.forename: P
authors.initials: P
authors.lastname: Debré
authors.forename: M D
authors.initials: MD
authors.lastname: Mossalayi
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D001491:Basophils / Q000502:physiology*; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007377:Interleukin-3 / Q000235:genetics / Q000502:physiology*; D015603:Keratinocytes / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D017455:Receptors, IgE / Q000235:genetics / Q000502:physiology*
chemical_list: D000911:Antibodies, Monoclonal; D007377:Interleukin-3; D012333:RNA, Messenger; D017455:Receptors, IgE