title: Human eosinophils constitutively express a unique serine protease, PRSS33.
abstract: BACKGROUND
  Eosinophils play important roles in asthma, especially airway remodeling, by producing various granule proteins, chemical mediators, cytokines, chemokines and proteases. However, protease production by eosinophils is not fully understood. In the present study, we investigated the production of eosinophil-specific proteases/proteinases by transcriptome analysis.
  
  
  METHODS
  Human eosinophils and other cells were purified from peripheral blood by density gradient sedimentation and negative/positive selections using immunomagnetic beads. Protease/proteinase expression in eosinophils and release into the supernatant were evaluated by microarray analysis, qPCR, ELISA, flow cytometry and immunofluorescence staining before and after stimulation with eosinophil-activating cytokines and secretagogues. mRNAs for extracellular matrix proteins in human normal fibroblasts were measured by qPCR after exposure to recombinant protease serine 33 (PRSS33) protein (rPRSS33), created with a baculovirus system.
  
  
  RESULTS
  Human eosinophils expressed relatively high levels of mRNA for metalloproteinase 25 (MMP25), a disintegrin and metalloprotease 8 (ADAM8), ADAM10, ADAM19 and PRSS33. Expression of PRSS33 was the highest and eosinophil-specific. PRSS33 mRNA expression was not affected by eosinophil-activating cytokines. Immunofluorescence staining showed that PRSS33 was co-localized with an eosinophil granule protein. PRSS33 was not detected in the culture supernatant of eosinophils even after stimulation with secretagogues, but its cell surface expression was increased. rPRSS33 stimulation of human fibroblasts increased expression of collagen and fibronectin mRNAs, at least in part via protease-activated receptor-2 activation.
  
  
  CONCLUSIONS
  Activated eosinophils may induce fibroblast extracellular matrix protein synthesis via cell surface expression of PRSS33, which would at least partly explain eosinophils' role(s) in airway remodeling.
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan; Department of Immune Regulation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Sumika
authors.initials: S
authors.lastname: Toyama
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Okada
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Matsuda
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Morita
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Saito
authors.affiliation: Institute for Clinical Research, Mie National Hospital, Mie, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Fujisawa
authors.affiliation: Laboratory of Systems Biology, Center for Experimental Medicine and Systems Biology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Saitama, 332-0012, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Nakae
authors.affiliation: Department of Immune Regulation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Karasuyama
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan. Electronic address: matsumoto-k@ncchd.go.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D001249:Asthma / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015415:Biomarkers; D015550:Cell Degranulation / Q000276:immunology; D002478:Cells, Cultured; D004804:Eosinophils / Q000276:immunology / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D005434:Flow Cytometry; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism; D009928:Organ Specificity / Q000235:genetics; D021381:Protein Transport; D057057:Serine Proteases / Q000235:genetics* / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D015415:Biomarkers; D057057:Serine Proteases
keywords: Eosinophil; Extracellular matrix; Protease/proteinase; Remodeling; Transcriptome