Targeting Key Factors Involved in Immune Reactions mediated by Tick Bites to the Carbohydrate alpha-Gal

• Applicants: Professor Dr. Tilo Biedermann; Privatdozent Dr. Jörg Fischer
• Subject Area: Clinical Immunology and Allergology ; Dermatology
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 392344742

• Final Report Year: 2023

Final Report Abstract

Alpha-gal is a carbohydrate with the potential to trigger allergic responses to mammalian meat and drugs of mammalian origin in humans. Sensitization to alpha-gal is mediated through the skin by tick bites and results in the induction of alpha-gal-specific IgE antibodies. Whereas immune responses to protein antigens are well characterized, immune responses to carbohydrates are so far poorly understood. However, treatment options for food allergies are limited to avoidance of the allergen and alleviation of symptoms. Thus, there is a clear need to elucidate the mechanisms resulting in sensitization to alpha-gal, including potential alpha-gal sources in ticks and mammalian blood. In this study, we performed in-depth analysis of tickderived and immunological factors involved in sensitization to alpha-gal. By screening mammalian fed and unfed ticks using microscopy and mass spectrometry, we identified proteins of host origin in fed ticks, indicating that residual glycoproteins and/or -lipids from former feeding may be a relevant source of alpha-gal responsible for sensitization in the skin. Moreover, we performed phenotyping of IgG subtypes and immune cell subsets in blood samples in individuals with recurrent tick bites and observed an increase in IgG1 and IgG2 and specific B cell subsets including plasma. The allergenicity of different alpha-gal-carrying glycoproteins and - lipids were studied in basophil activation test in alpha-gal IgE-positive individuals and observed that rabbit blood-derived glycolipids strongly activated basophils. Finally, we established a mouse model of alpha-gal allergy involving repetitive intracutaneous administration of an alpha-gal-carrying self-protein, resulting in efficient sensitization accompanied by induction of alpha-gal-specific IgE and IgG1 antibodies. Administration of both glycoproteins and glycolipids elicited anaphylaxis in sensitized mice, confirming the potent allergenicity of the rabbit-derived glycolipids in an in vivo setting. In accordance with findings in human patients, our analysis of immune cell phenotypes in sensitized skin and skin-draining lymph nodes revealed an increase in skin basophils and alpha-gal-specific B cells in lymph nodes. All in all, these new insights into the sources and mechanisms of alpha-gal sensitization will contribute to the improvement of patients’ diagnostic and care in the future.

Publications

• Drugs of porcine origin—A risk for patients with α-gal syndrome?. The Journal of Allergy and Clinical Immunology: In Practice, 7(5), 1687-1690.e3.
  Swiontek, Kyra; Morisset, Martine; Codreanu-Morel, Françoise; Fischer, Jörg; Mehlich, Jana; Darsow, Ulf; Petitpain, Nadine; Biedermann, Tilo; Ollert, Markus; Eberlein, Bernadette & Hilger, Christiane
  
• Role and Mechanism of Galactose-Alpha-1,3-Galactose in the Elicitation of Delayed Anaphylactic Reactions to Red Meat. Current Allergy and Asthma Reports, 19(1).
  Hilger, Christiane; Fischer, Jörg; Wölbing, Florian & Biedermann, Tilo
  
• The basophil activation test differentiates between patients with alpha-gal syndrome and asymptomatic alpha-gal sensitization. Journal of Allergy and Clinical Immunology, 143(1), 182-189.
  Mehlich, Jana; Fischer, Jörg; Hilger, Christiane; Swiontek, Kyra; Morisset, Martine; Codreanu-Morel, Françoise; Schiener, Maximilian; Blank, Simon; Ollert, Markus; Darsow, Ulf; Biedermann, Tilo & Eberlein, Bernadette
  
• Negative Oral Provocation Test With Porcine Pancreatic Enzyme Plus Cofactors Despite Confirmed α-Gal Syndrome. Journal of Investigational Allergology and Clinical Immunology, 30(6), 468-469.
  Eberlein, B.; Mehlich, J.; Reidenbach, K.; Pilz, C.; Hilger, C.; Darsow, U.; Brockow, K. & Biedermann, T.
  
• Spatial distribution of alpha-gal in Ixodes ricinus – A histological study. Ticks and Tick-borne Diseases, 11(5), 101506.
  Fischer, Jörg; Riel, Simon; Fehrenbacher, Birgit; Frank, Alisa; Schaller, Martin; Biedermann, Tilo; Hilger, Christiane & Mackenstedt, Ute
  
• The History of Carbohydrates in Type I Allergy. Frontiers in Immunology, 11.
  Hils, Miriam; Wölbing, Florian; Hilger, Christiane; Fischer, Jörg; Hoffard, Nils & Biedermann, Tilo
  
• Carbohydrate epitopes currently recognized as targets for IgE antibodies. Allergy, 76(8), 2383-2394.
  Platts‐Mills, Thomas A.; Hilger, Christiane; Jappe, Uta; van Hage, Marianne; Gadermaier, Gabriele; Spillner, Edzard; Lidholm, Jonas; Keshavarz, Behnam; Aalberse, Rob C.; van Ree, Ronald; Goodman, Richard E. & Pomés, Anna
  
• Delayed reaction in alpha‐gal allergy is reflected in serum levels after ingestion of pork kidney, and absorption is dependent on food processing. Clinical & Experimental Allergy, 52(1), 197-200.
  Eller, Esben; Stahl, Skov Per; Baumann, Katrine; Hilger, Christiane; Ollert, Markus & Bindslev‐Jensen, Carsten
  
• Experience with polyethylene glycol allergy‐guided risk management for COVID‐19 vaccine anaphylaxis. Allergy, 77(7), 2200-2210.
  Brockow, Knut; Mathes, Sonja; Fischer, Jörg; Volc, Sebastian; Darsow, Ulf; Eberlein, Bernadette & Biedermann, Tilo
  
• Pre-digest of unprotected DNA by Benzonase improves the representation of living skin bacteria and efficiently depletes host DNA. Microbiome, 9(1).
  Amar, Yacine; Lagkouvardos, Ilias; Silva, Rafaela L.; Ishola, Oluwaseun Ayodeji; Foesel, Bärbel U.; Kublik, Susanne; Schöler, Anne; Niedermeier, Sebastian; Bleuel, Rachela; Zink, Alexander; Neuhaus, Klaus; Schloter, Michael; Biedermann, Tilo & Köberle, Martin
  
• The basophil activation test differentiates between patients with wheat‐dependent exercise‐induced anaphylaxis and control subjects using gluten and isolated gluten protein types. Clinical and Translational Allergy, 11(6).
  Gabler, Angelika Miriam; Gebhard, Julia; Eberlein, Bernadette; Biedermann, Tilo; Scherf, Katharina Anne & Brockow, Knut
  
• A novel monoclonal IgG1 antibody specific for Galactose-alpha-1,3-galactose questions alpha-Gal epitope expression by bacteria. Frontiers in Immunology, 13.
  Kreft, Luisa; Schepers, Aloys; Hils, Miriam; Swiontek, Kyra; Flatley, Andrew; Janowski, Robert; Mirzaei, Mohammadali Khan; Dittmar, Michael; Chakrapani, Neera; Desai, Mahesh S.; Eyerich, Stefanie; Deng, Li; Niessing, Dierk; Fischer, Konrad; Feederle, Regina; Blank, Simon; Schmidt-Weber, Carsten B.; Hilger, Christiane; Biedermann, Tilo & Ohnmacht, Caspar
  
• Alpha-Gal-Syndrom. Der Hautarzt, 73(3), 195-200.
  Fischer, J.; Reepschläger, T.; Schricker, T. & Raap, U.
  
• Could Cat Flea Bites Contribute to a-Gal Serum IgE Levels in Humans?. Journal of Investigational Allergology and Clinical Immunology, 32(6), 494-495.
  Stenger, F.; Seidel, P.; Schricker, T.; Volc, S. & Fischer, J.
  
• Platts-Mills TAE. Allergy to mammalian meat. In: Molecular Allergology. User’s Guide 2.0. published EAACI 2022. ISBN 978-3-9524815-4-7.
  van Hage M.; Biedermann T. & Hilger C.
  
• α-Gal present on both glycolipids and glycoproteins contributes to immune response in meat-allergic patients. Journal of Allergy and Clinical Immunology, 150(2), 396-405.e11.
  Chakrapani, Neera; Fischer, Jörg; Swiontek, Kyra; Codreanu-Morel, Françoise; Hannachi, Farah; Morisset, Martine; Mugemana, Clément; Bulaev, Dmitry; Blank, Simon; Bindslev-Jensen, Carsten; Biedermann, Tilo; Ollert, Markus & Hilger, Christiane