title: Atopic donor status does not influence the uptake of the major grass pollen allergen, Phl p 5, by dendritic cells.
abstract: Dendritic cells (DCs) are sentinels of the immune system for antigen recognition and uptake, as well as presentation to naïve T cells for stimulation or priming. Internalization and endocytic degradation of allergens by DCs are important steps required for T cell priming. In the current study we investigated binding and internalization of purified recombinant non-glycosylated grass pollen allergen, Phl p 5, and natural non-specific lipid transfer protein from sunflower, SF-nsLTP to human monocyte derived dendritic cells (MoDCs). Colocalization of Phl p 5 with low affinity (CD23) or high affinity receptor (FcεRI) was investigated by immunofluorescence staining. Likewise, localization of the allergens in early (EE) and late endosomes (LE) was detected by co-staining for early endosome antigen (EEA1) and lysosomal-associated membrane protein 1 (LAMP1). In our experimental setting we could demonstrate that Phl p 5 as well as SF-nsLTP bound to MoDCs from both, grass pollen allergic and non-allergic individuals. Competitive allergen uptake experiments demonstrated non-preferential and simultaneous uptake of Phl p 5 and SF-nsLTP by MoDCs. No overlap of signals from Phl p 5 and CD23 or FcεRI was detectable, excluding IgE-mediated uptake for this allergen. Both allergens, Phl p 5 and SF-nsLTP, were localized in early and late endosomes. The present study applied a set of methods to assess the allergen uptake by MoDCs in an in vitro model. No qualitative and quantitative differences in the allergen uptake of both, Phl p 5 and SF-nsLTP were detected in single and competitive assays.
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: kazem.ashjaei@meduniwien.ac.at.
authors.forename: Kazem
authors.initials: K
authors.lastname: Ashjaei
authors.affiliation: Vienna Institute of Biotechnology - VIBT, University of Natural Resources and Life Sciences, Vienna, Austria. Electronic address: dieter.palmberger@boku.ac.at.
authors.forename: Dieter
authors.initials: D
authors.lastname: Palmberger
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: merima.bublin@meduniwien.ac.at.
authors.forename: Merima
authors.initials: M
authors.lastname: Bublin
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: erika.bajna@meduniwien.ac.at.
authors.forename: Erika
authors.initials: E
authors.lastname: Bajna
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: heimo.breiteneder@meduniwien.ac.at.
authors.forename: Heimo
authors.initials: H
authors.lastname: Breiteneder
authors.affiliation: Vienna Institute of Biotechnology - VIBT, University of Natural Resources and Life Sciences, Vienna, Austria. Electronic address: reingard.grabherr@boku.ac.at.
authors.forename: Reingard
authors.initials: R
authors.lastname: Grabherr
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: isabella.ellinger@meduniwien.ac.at.
authors.forename: Isabella
authors.initials: I
authors.lastname: Ellinger
authors.affiliation: Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria. Electronic address: Karin.Hoffmann-Sommergruber@meduniwien.ac.at.
authors.forename: Karin
authors.initials: K
authors.lastname: Hoffmann-Sommergruber
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology* / Q000378:metabolism; D001692:Biological Transport; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis / Q000276:immunology* / Q000378:metabolism; D007073:Immunoglobulin E / Q000276:immunology / Q000378:metabolism; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D010940:Plant Proteins / Q000276:immunology* / Q000378:metabolism; D011058:Pollen / Q000276:immunology*; D011485:Protein Binding; D017455:Receptors, IgE / Q000378:metabolism; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D055815:Young Adult
chemical_list: D000485:Allergens; C076049:Phl p V protein, Phleum pratense; D010940:Plant Proteins; D017455:Receptors, IgE; D007073:Immunoglobulin E
keywords: Allergen; Endocytosis; Grass pollen; Monocyte derived dendritic cells; Phl p 5; SF-nsLTP