Franziska Roth-Walter1, Sheriene Moussa Afify2, Luis F Pacios3, Bart R Blokhuis4, Frank Redegeld4, Andreas Regner5, Lisa-Marie Petje5, Alessandro Fiocchi6, Eva Untersmayr7, Zdenek Dvorak8, Karin Hufnagl9, Isabella Pali-Schöll9, Erika Jensen-Jarolim10. 1. The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria; Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria. Electronic address: franziska.roth-walter@meduniwien.ac.at. 2. The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria; Laboratory Medicine and Immunology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt. 3. Biotechnology Department, ETSIAAB, Center for Plant Biotechnology and Genomics, CBGP (UPM-INIA), Technical University of Madrid, Madrid, Spain. 4. Faculty of Science, Division of Pharmacology, Department of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands. 5. The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria. 6. Childrens Hospital Bambino Gesù, Rome, Italy. 7. Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria. 8. Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Olomouc, Czech Republic. 9. The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria; Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria. 10. The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria; Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria. Electronic address: erika.jensen-jarolim@medunwien.ac.at.
Abstract
BACKGROUND: Beta-lactoglobulin (BLG) is a bovine lipocalin in milk with an innate defense function. The circumstances under which BLG is associated with tolerance of or allergy to milk are not understood. OBJECTIVE: Our aims were to assess the capacity of ligand-free apoBLG versus loaded BLG (holoBLG) to protect mice against allergy by using an iron-quercetin complex as an exemplary ligand and to study the molecular mechanisms of this protection. METHODS: Binding of iron-quercetin to BLG was modeled and confirmed by spectroscopy and docking calculations. Serum IgE binding to apoBLG and holoBLG in children allergic to milk and children tolerant of milk was assessed. Mice were intranasally treated with apoBLG versus holoBLG and analyzed immunologically after systemic challenge. Aryl hydrocarbon receptor (AhR) activation was evaluated with reporter cells and Cyp1A1 expression. Treated human PBMCs and human mast cells were assessed by fluorescence-activated cell sorting and degranulation, respectively. RESULTS: Modeling predicted masking of major IgE and T-cell epitopes of BLG by ligand binding. In line with this modeling, IgE binding in children allergic to milk was reduced toward holoBLG, which also impaired degranulation of mast cells. In mice, only treatments with holoBLG prevented allergic sensitization and anaphylaxis, while sustaining regulatory T cells. BLG facilitated quercetin-dependent AhR activation and, downstream of AhR, lung Cyp1A1 expression. HoloBLG shuttled iron into monocytic cells and impaired their antigen presentation. CONCLUSION: The cargo of holoBLG is decisive in preventing allergy in vivo. BLG without cargo acted as an allergen in vivo and further primed human mast cells for degranulation in an antigen-independent fashion. Our data provide a mechanistic explanation why the same proteins can act either as tolerogens or as allergens.
BACKGROUND:Beta-lactoglobulin (BLG) is a bovine lipocalin in milk with an innate defense function. The circumstances under which BLG is associated with tolerance of or allergy to milk are not understood. OBJECTIVE: Our aims were to assess the capacity of ligand-free apoBLG versus loaded BLG (holoBLG) to protect mice against allergy by using an iron-quercetin complex as an exemplary ligand and to study the molecular mechanisms of this protection. METHODS: Binding of iron-quercetin to BLG was modeled and confirmed by spectroscopy and docking calculations. Serum IgE binding to apoBLG and holoBLG in children allergic to milk and children tolerant of milk was assessed. Mice were intranasally treated with apoBLG versus holoBLG and analyzed immunologically after systemic challenge. Aryl hydrocarbon receptor (AhR) activation was evaluated with reporter cells and Cyp1A1 expression. Treated human PBMCs and human mast cells were assessed by fluorescence-activated cell sorting and degranulation, respectively. RESULTS: Modeling predicted masking of major IgE and T-cell epitopes of BLG by ligand binding. In line with this modeling, IgE binding in children allergic to milk was reduced toward holoBLG, which also impaired degranulation of mast cells. In mice, only treatments with holoBLG prevented allergic sensitization and anaphylaxis, while sustaining regulatory T cells. BLG facilitated quercetin-dependent AhR activation and, downstream of AhR, lung Cyp1A1 expression. HoloBLG shuttled iron into monocytic cells and impaired their antigen presentation. CONCLUSION: The cargo of holoBLG is decisive in preventing allergy in vivo. BLG without cargo acted as an allergen in vivo and further primed human mast cells for degranulation in an antigen-independent fashion. Our data provide a mechanistic explanation why the same proteins can act either as tolerogens or as allergens.
Authors: Maksymilian Chruszcz; Fook Tim Chew; Karin Hoffmann-Sommergruber; Barry K Hurlburt; Geoffrey A Mueller; Anna Pomés; Juha Rouvinen; Mayte Villalba; Birgitta M Wöhrl; Heimo Breiteneder Journal: Allergy Date: 2021-05-02 Impact factor: 14.710
Authors: Isabella Pali-Schöll; Rodolfo Bianchini; Sheriene Moussa Afify; Gerlinde Hofstetter; Simona Winkler; Stella Ahlers; Theresa Altemeier; Hanna Mayerhofer; Karin Hufnagl; Anna D J Korath; Christina Pranger; Raimund Widhalm; Stephan Hann; Thomas Wittek; Anne Kasper-Giebl; Luis F Pacios; Franziska Roth-Walter; Donata Vercelli; Erika von Mutius; Erika Jensen-Jarolim Journal: Clin Transl Allergy Date: 2022-02-12 Impact factor: 5.871
Authors: Sebastian A Jensen; Alessandro Fiocchi; Ton Baars; Galateja Jordakieva; Anna Nowak-Wegrzyn; Isabella Pali-Schöll; Stefano Passanisi; Christina L Pranger; Franziska Roth-Walter; Kristiina Takkinen; Amal H Assa'ad; Carina Venter; Erika Jensen-Jarolim Journal: World Allergy Organ J Date: 2022-09-15 Impact factor: 5.516