Noemi Zbären1, Daniel Brigger1, Daniel Bachmann2, Arthur Helbling3, Lukas Jörg3, Michael P Horn4, Johannes M Schmid5, Hans Jürgen Hoffmann5, Jean-Pierre Kinet6, Thomas Kaufmann7, Alexander Eggel8. 1. Department of BioMedical Research, University of Bern, Bern, Switzerland; Department of Rheumatology, Immunology and Allergology, University Hospital Bern, Bern, Switzerland. 2. Institute of Pharmacology, University of Bern, Bern, Switzerland. 3. Division of Allergology and Clinical Immunology, Department of Pneumology, Inselspital, University Hospital Bern, Bern, Switzerland. 4. Department of Clinical Chemistry, Inselspital University Hospital, Bern, Switzerland. 5. Department of Respiratory Diseases and Allergy, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark. 6. Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass. 7. Institute of Pharmacology, University of Bern, Bern, Switzerland. Electronic address: thomas.kaufmann@pki.unibe.ch. 8. Department of BioMedical Research, University of Bern, Bern, Switzerland; Department of Rheumatology, Immunology and Allergology, University Hospital Bern, Bern, Switzerland. Electronic address: alexander.eggel@dbmr.unibe.ch.
Abstract
BACKGROUND: Clinical management of allergic diseases has been hampered by the lack of safe and convenient tests to reliably identify culprit allergens and to closely follow changes in disease activity over time. Because allergy diagnosis is a complex and laborious multistep procedure, there is an urgent need for simpler but still functionally accurate ex vivo assays allowing objective diagnosis, substantiating treatment choices, and quantifying therapeutic responses. OBJECTIVE: In this study, we sought to develop a novel functional cell-based assay that relies on passive sensitization of allergic effector cells with patient serum, circumventing current limitations in allergy diagnosis. METHODS: We genetically engineered a conditional homeobox B8 (Hoxb8)-immortalized progenitor line from the bone marrow of mice that are transgenic for the human high-affinity IgE receptor (FcεRIα). These cells can be reproducibly differentiated into mature Hoxb8 mast cells within 5 days of culture in virtually unlimited numbers. RESULTS: We demonstrate that the established Hoxb8 mast cell assay can be used to accurately measure total IgE levels, identify culprit allergens, longitudinally monitor allergen-specific immunotherapy, and potentially determine the time point of tolerance induction upon allergen-specific immunotherapy in patients with allergy. To facilitate the analysis of large testing volumes, we demonstrate a proof-of-concept for a high-throughput screening application based on fluorescent cell barcoding using the engineered Hoxb8 mast cells. CONCLUSIONS: Our results indicate that this novel mast cell assay could represent a valuable tool to support clinicians in the identification of IgE-mediated allergies and in the quantification of treatment efficacy as well as duration of therapeutic response.
BACKGROUND: Clinical management of allergic diseases has been hampered by the lack of safe and convenient tests to reliably identify culprit allergens and to closely follow changes in disease activity over time. Because allergy diagnosis is a complex and laborious multistep procedure, there is an urgent need for simpler but still functionally accurate ex vivo assays allowing objective diagnosis, substantiating treatment choices, and quantifying therapeutic responses. OBJECTIVE: In this study, we sought to develop a novel functional cell-based assay that relies on passive sensitization of allergic effector cells with patient serum, circumventing current limitations in allergy diagnosis. METHODS: We genetically engineered a conditional homeobox B8 (Hoxb8)-immortalized progenitor line from the bone marrow of mice that are transgenic for the human high-affinity IgE receptor (FcεRIα). These cells can be reproducibly differentiated into mature Hoxb8 mast cells within 5 days of culture in virtually unlimited numbers. RESULTS: We demonstrate that the established Hoxb8 mast cell assay can be used to accurately measure total IgE levels, identify culprit allergens, longitudinally monitor allergen-specific immunotherapy, and potentially determine the time point of tolerance induction upon allergen-specific immunotherapy in patients with allergy. To facilitate the analysis of large testing volumes, we demonstrate a proof-of-concept for a high-throughput screening application based on fluorescent cell barcoding using the engineered Hoxb8 mast cells. CONCLUSIONS: Our results indicate that this novel mast cell assay could represent a valuable tool to support clinicians in the identification of IgE-mediated allergies and in the quantification of treatment efficacy as well as duration of therapeutic response.
Authors: Jada Suber; Yugen Zhang; Ping Ye; Rishu Guo; A Wesley Burks; Michael D Kulis; Scott A Smith; Onyinye I Iweala Journal: Front Immunol Date: 2022-09-29 Impact factor: 8.786