1
|
Rinaldi DA, Kanagy WK, Kaye HC, Grattan RM, Lucero SR, Pérez MP, Wester MJ, Lidke KA, Wilson BS, Lidke DS. Antigen Geometry Tunes Mast Cell Signaling Through Distinct FcεRI Aggregation and Structural Changes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.552060. [PMID: 37609336 PMCID: PMC10441289 DOI: 10.1101/2023.08.04.552060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Immunoreceptor tyrosine-based activation motif (ITAM)-containing Fc receptors are critical components of the innate and adaptive immune systems. FcεRI mediates the allergic response via crosslinking of IgE-bound receptors by multivalent antigens. Yet, the underlying molecular mechanisms that govern the response of FcεRI to specific antigens remain poorly understood. We compared responses induced by two antigens with distinct geometries, high valency DNP-BSA and trivalent DF3, and found unique secretion and receptor phosphorylation profiles that are due to differential recruitment of Lyn and SHIP1. To understand how these two antigens can cause such markedly different outcomes, we used direct stochastic optical reconstruction microscopy (dSTORM) super-resolution imaging combined with Bayesian Grouping of Localizations (BaGoL) analysis to compare the nanoscale characteristics of FcεRI aggregates. DF3 aggregates were found to be smaller and more densely packed than DNP-BSA aggregates. Using lifetime-based Förster resonance energy transfer (FRET) measurements, we discovered that FcεRI subunits undergo structural rearrangements upon crosslinking with either antigen, and in response to interaction with monovalent antigen presented on a supported lipid bilayer. The extent of conformational change is positively correlated with signaling efficiency. Finally, we provide evidence for forces in optimizing FcεRI signaling, such that immobilizing DF3 on a rigid surface promoted degranulation while increasing DNP-BSA flexibility lowered degranulation. These results provide a link between the physical attributes of allergens, including size, shape, valency, and flexibility, and FcεRI signaling strength. Thus, the antigen modulates mast cell outcomes by creating unique aggregate geometries that tune FcεRI conformation, phosphorylation and signaling partner recruitment.
Collapse
Affiliation(s)
- Derek A. Rinaldi
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - William K. Kanagy
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Present address: Department of Immunology, University of Minnesota, Minneapolis, MN 55455
| | - Hannah C. Kaye
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Rachel M. Grattan
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Shayna R. Lucero
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | | | - Michael J. Wester
- Department Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131
| | - Keith A. Lidke
- Department Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Bridget S. Wilson
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Diane S. Lidke
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| |
Collapse
|
2
|
Schneider L, Rabe KS, Domínguez CM, Niemeyer CM. Hapten-Decorated DNA Nanostructures Decipher the Antigen-Mediated Spatial Organization of Antibodies Involved in Mast Cell Activation. ACS NANO 2023; 17:6719-6730. [PMID: 36990450 PMCID: PMC10100567 DOI: 10.1021/acsnano.2c12647] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 03/07/2023] [Indexed: 06/19/2023]
Abstract
The immunological response of mast cells is controlled by the multivalent binding of antigens to immunoglobulin E (IgE) antibodies bound to the high-affinity receptor FcεRI on the cell membrane surface. However, the spatial organization of antigen-antibody-receptor complexes at the nanometer scale and the structural constraints involved in the initial events at the cell surface are not yet fully understood. For example, it is unclear what influence the affinity and nanoscale distance between the binding partners involved have on the activation of mast cells to degranulate inflammatory mediators from storage granules. We report the use of DNA origami nanostructures (DON) functionalized with different arrangements of the haptenic 2,4-dinitrophenyl (DNP) ligand to generate multivalent artificial antigens with full control over valency and nanoscale ligand architecture. To investigate the spatial requirements for mast cell activation, the DNP-DON complexes were initially used in surface plasmon resonance (SPR) analysis to study the binding kinetics of isolated IgE under physiological conditions. The most stable binding was observed in a narrow window of approximately 16 nm spacing between haptens. In contrast, affinity studies with FcεRI-linked IgE antibodies on the surface of rat basophilic leukemia cells (RBL-2H3) indicated virtually no distance-dependent variations in the binding of the differently structured DNP-DON complexes but suggested a supramolecular oligovalent nature of the interaction. Finally, the use of DNP-DON complexes for mast cell activation revealed that antigen-directed tight assembly of antibody-receptor complexes is the critical factor for triggering degranulation, even more critical than ligand valence. Our study emphasizes the significance of DNA nanostructures for the study of fundamental biological processes.
Collapse
|
3
|
Adnan A, Acharya S, Alenazy LA, de las Vecillas L, Giavina Bianchi P, Picard M, Calbache-Gil L, Romero-Pinedo S, Abadí´a-Molina AC, Kerr W, Pedicone C, Nagai J, Hollers E, Dwyer D, Castells M. Multistep IgE Mast Cell Desensitization Is a Dose- and Time-Dependent Process Partially Regulated by SHIP-1. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:709-720. [PMID: 36881903 PMCID: PMC9986054 DOI: 10.4049/jimmunol.2100485] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 12/22/2022] [Indexed: 03/09/2023]
Abstract
Multistep mast cell desensitization blocks the release of mediators following IgE crosslinking with increasing doses of Ag. Although its in vivo application has led to the safe reintroduction of drugs and foods in IgE-sensitized patients at risk for anaphylaxis, the mechanisms of the inhibitory process have remained elusive. We sought to investigate the kinetics, membrane, and cytoskeletal changes and to identify molecular targets. IgE-sensitized wild-type murine (WT) and FcεRIα humanized (h) bone marrow mast cells were activated and desensitized with DNP, nitrophenyl, dust mites, and peanut Ags. The movements of membrane receptors, FcεRI/IgE/Ag, actin, and tubulin and the phosphorylation of Syk, Lyn, P38-MAPK, and SHIP-1 were assessed. Silencing SHIP-1 protein was used to dissect the SHIP-1 role. Multistep IgE desensitization of WT and transgenic human bone marrow mast cells blocked the release of β-hexosaminidase in an Ag-specific fashion and prevented actin and tubulin movements. Desensitization was regulated by the initial Ag dose, number of doses, and time between doses. FcεRI, IgE, Ags, and surface receptors were not internalized during desensitization. Phosphorylation of Syk, Lyn, p38 MAPK, and SHIP-1 increased in a dose-response manner during activation; in contrast, only SHIP-1 phosphorylation increased in early desensitization. SHIP-1 phosphatase function had no impact on desensitization, but silencing SHIP-1 increased β-hexoxaminidase release, preventing desensitization. Multistep IgE mast cell desensitization is a dose- and time-regulated process that blocks β-hexosaminidase, impacting membrane and cytoskeletal movements. Signal transduction is uncoupled, favoring early phosphorylation of SHIP-1. Silencing SHIP-1 impairs desensitization without implicating its phosphatase function.
Collapse
Affiliation(s)
- Ather Adnan
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
- Texas A&M Health Science Center, College of Medicine, Houston, TX
| | - Shree Acharya
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Leila A. Alenazy
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
- Division of Allergy and Clinical Immunology, Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Leticia de las Vecillas
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
- Department of Allergy, Marqués de Valdecilla University Hospital – Instituto de Investigación Marques de Valdecilla, Santander, Spain
| | - Pedro Giavina Bianchi
- Clinical Immunology and Allergy Division, School of Medicine, Universidade de São Paulo, R. Prof. Artur Ramos Sao Paulo, Brazil
| | - Matthieu Picard
- Division of Allergy and Clinical Immunology, Department of Medicine, Hôpital Maisonneuve-Rosemont, Université de Montréal, Montreal, QC, Canada
| | - Lucia Calbache-Gil
- Unidad de Inmunología, IBIMER, CIBM, Universidad de Granada, Granada, Spain
- Departamento de Bioquímica y Biología Molecular III e Inmunología, Facultad de Medicina, Universidad de Granada, Granada, Spain
| | - Salvador Romero-Pinedo
- Unidad de Inmunología, IBIMER, CIBM, Universidad de Granada, Granada, Spain
- Departamento de Bioquímica y Biología Molecular III e Inmunología, Facultad de Medicina, Universidad de Granada, Granada, Spain
| | - Ana Clara Abadí´a-Molina
- Unidad de Inmunología, IBIMER, CIBM, Universidad de Granada, Granada, Spain
- Departamento de Bioquímica y Biología Molecular III e Inmunología, Facultad de Medicina, Universidad de Granada, Granada, Spain
| | - William Kerr
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY
| | - Chiara Pedicone
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY
| | - Jun Nagai
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Eleanor Hollers
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Daniel Dwyer
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Mariana Castells
- Division of Allergy and Immunology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| |
Collapse
|
4
|
Chong G, MacKerell AD. Spatial requirements for ITAM signaling in an intracellular natural killer cell model membrane. Biochim Biophys Acta Gen Subj 2022; 1866:130221. [PMID: 35933027 PMCID: PMC9420803 DOI: 10.1016/j.bbagen.2022.130221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/27/2022] [Accepted: 07/31/2022] [Indexed: 11/17/2022]
Abstract
FcγRIIIa-FcεRIγ complexes, upon stimulation by antibodies, cluster to initiate intracellular signaling and activate natural killer (NK) cells. Intracellular signaling involves Lck phosphorylation of ITAMs of each monomer of a FcεRIγ homodimer in a FcγRIIIa-FcεRIγ complex and subsequent binding of two phosphotyrosines (pY) in tandem by a Syk family kinase. However, how FcR clustering triggers ITAM signaling is not resolved. Molecular modeling and dynamics (MD) simulations are applied to generate ensembles of structures of the FcγRIIIa and FcεRIγ homodimeric cytoplasmic tails of FcγRIIIa-FcεRIγ complexes based on the transmembrane helices and cytoplasmic tails spaced 120, 80, and 50 Å apart to model different extents of clustering. Site-identification by ligand competitive saturation method with Monte Carlo sampling (SILCS-MC) is used to model how Lck could phosphorylate a diversity of ITAM conformations. At 80 Å separation between FcγRIIIa-FcεRIγ complexes, Lck can perform multiple phosphorylations on individual and multiple ITAMs across complexes, including potential sequential phosphorylation events. Syk may then potentially bind the two pYs within a single ITAM in tandem in isolated FcγRIIIa-FcεRIγ complexes, as observed in CD3ε and ζ chains of T cell receptors by the Syk family kinase ZAP-70. In addition, at 50 Å separation between complexes, unique to natural killer cells over T cells, Syk could potentially bind in tandem to pYs in different ITAMs across FcγRIIIa-FcεRIγ complexes. Thus, we predict that an ensemble of spatial orientations of the ITAMS of FcγRIIIa-FcεRIγ complexes that occur upon clustering lead to ITAM phosphorylation by Lck and subsequent Syk activity thereby facilitating downstream signaling.
Collapse
Affiliation(s)
- Gene Chong
- Computer Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201, United States
| | - Alexander D MacKerell
- Computer Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201, United States.
| |
Collapse
|
5
|
Bratti M, Vibhushan S, Longé C, Koumantou D, Ménasché G, Benhamou M, Varin-Blank N, Blank U, Saveanu L, Ben Mkaddem S. Insulin-regulated aminopeptidase contributes to setting the intensity of FcR-mediated inflammation. Front Immunol 2022; 13:1029759. [PMID: 36389775 PMCID: PMC9647545 DOI: 10.3389/fimmu.2022.1029759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 10/12/2022] [Indexed: 11/25/2022] Open
Abstract
The function of intracellular trafficking in immune-complex triggered inflammation remains poorly understood. Here, we investigated the role of Insulin-Regulated Amino Peptidase (IRAP)-positive endosomal compartments in Fc receptor (FcR)-induced inflammation. Less severe FcγR-triggered arthritis, active systemic anaphylaxis and FcεRI-triggered passive systemic anaphylaxis were observed in IRAP-deficient versus wild-type mice. In mast cells FcεRI stimulation induced rapid plasma membrane recruitment of IRAP-positive endosomes. IRAP-deficient cells exhibited reduced secretory responses, calcium signaling and activating SykY519/520 phosphorylation albeit receptor tyrosine phosphorylation on β and γ subunits was not different. By contrast, in the absence of IRAP, SHP1-inactivating phosphorylation on Ser591 that controls Syk activity was decreased. Ex-vivo cell profiling after FcγR-triggered anaphylaxis confirmed decreased phosphorylation of both SykY519/520 and SHP-1S591 in IRAP-deficient neutrophils and monocytes. Thus, IRAP-positive endosomal compartments, in promoting inhibition of SHP-1 during FcR signaling, control the extent of phosphorylation events at the plasma membrane and contribute to setting the intensity of immune-complex triggered inflammatory diseases.
Collapse
Affiliation(s)
- Manuela Bratti
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
| | - Shamila Vibhushan
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
| | - Cyril Longé
- Université Paris Cité, Imagine Institute, Laboratory of Molecular basis of altered immune homeostasis, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1163, Paris, France
| | - Despoina Koumantou
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
| | - Gaël Ménasché
- Université Paris Cité, Imagine Institute, Laboratory of Molecular basis of altered immune homeostasis, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1163, Paris, France
| | - Marc Benhamou
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
| | - Nadine Varin-Blank
- Institut National de la Santé et de la Recherche Médicale (INSERM) U978, Université Paris 13 Sorbonne Paris Nord, Unité de Formation et de Recherche (UFR) Santé Médecine et Biologie Humaine (SMBH), Bobigny, France
| | - Ulrich Blank
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
- *Correspondence: Ulrich Blank,
| | - Loredana Saveanu
- Université Paris Cité, Centre de Recherche sur l’Inflammation, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1149, Centre National de la Recherche Scientifique (CNRS) Equipe Mixte de Recherche(EMR)-8252, Faculté de Médecine site Bichat, Paris, France
- Université Paris Cité, Laboratoire d’Excellence INFLAMEX, Paris, France
| | - Sanae Ben Mkaddem
- Institut National de la Santé et de la Recherche Médicale (INSERM) U978, Université Paris 13 Sorbonne Paris Nord, Unité de Formation et de Recherche (UFR) Santé Médecine et Biologie Humaine (SMBH), Bobigny, France
- Institute of biological Sciences, Mohammed VI Polytechnic University (UM6P), Ben-Guerir, Morocco
| |
Collapse
|
6
|
Kanagy WK, Cleyrat C, Fazel M, Lucero SR, Bruchez MP, Lidke KA, Wilson BS, Lidke DS. Docking of Syk to FcεRI is enhanced by Lyn but limited in duration by SHIP1. Mol Biol Cell 2022; 33:ar89. [PMID: 35793126 PMCID: PMC9582627 DOI: 10.1091/mbc.e21-12-0603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The high-affinity immunoglobulin E (IgE) receptor, FcεRI, is the primary immune receptor found on mast cells and basophils. Signal initiation is classically attributed to phosphorylation of FcεRI β− and γ-subunits by the Src family kinase (SFK) Lyn, followed by the recruitment and activation of the tyrosine kinase Syk. FcεRI signaling is tuned by the balance between Syk-driven positive signaling and the engagement of inhibitory molecules, including SHIP1. Here, we investigate the mechanistic contributions of Lyn, Syk, and SHIP1 to the formation of the FcεRI signalosome. Using Lyn-deficient RBL-2H3 mast cells, we found that another SFK can weakly monophosphorylate the γ-subunit, yet Syk still binds the incompletely phosphorylated immunoreceptor tyrosine-based activation motifs (ITAMs). Once recruited, Syk further enhances γ-phosphorylation to propagate signaling. In contrast, the loss of SHIP1 recruitment indicates that Lyn is required for phosphorylation of the β-subunit. We demonstrate two noncanonical Syk binding modes, trans γ-bridging and direct β-binding, that can support signaling when SHIP1 is absent. Using single particle tracking, we reveal a novel role of SHIP1 in regulating Syk activity, where the presence of SHIP1 in the signaling complex acts to increase the Syk:receptor off-rate. These data suggest that the composition and dynamics of the signalosome modulate immunoreceptor signaling activities.
Collapse
Affiliation(s)
- William K Kanagy
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Cédric Cleyrat
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Mohamadreza Fazel
- Department of Physics, University of New Mexico, Albuquerque, NM 87131
| | - Shayna R Lucero
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Marcel P Bruchez
- Department of Biological Sciences and Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Keith A Lidke
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131.,Department of Physics, University of New Mexico, Albuquerque, NM 87131
| | - Bridget S Wilson
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Diane S Lidke
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| |
Collapse
|
7
|
Nagata Y, Suzuki R. FcεRI: A Master Regulator of Mast Cell Functions. Cells 2022; 11:cells11040622. [PMID: 35203273 PMCID: PMC8870323 DOI: 10.3390/cells11040622] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/29/2022] [Accepted: 02/09/2022] [Indexed: 02/04/2023] Open
Abstract
Mast cells (MCs) perform multiple functions thought to underlie different manifestations of allergies. Various aspects of antigens (Ags) and their interactions with immunoglobulin E (IgE) cause diverse responses in MCs. FcεRI, a high-affinity IgE receptor, deciphers the Ag–IgE interaction and drives allergic responses. FcεRI clustering is essential for signal transduction and, therefore, determines the quality of MC responses. Ag properties precisely regulate FcεRI dynamics, which consequently initiates differential outcomes by switching the intracellular-signaling pathway, suggesting that Ag properties can control MC responses, both qualitatively and quantitatively. Thus, the therapeutic benefits of FcεRI-targeting strategies have long been examined. Disrupting IgE–FcεRI interactions is a potential therapeutic strategy because the binding affinity between IgE and FcεRI is extremely high. Specifically, FcεRI desensitization, due to internalization, is also a potential therapeutic target that is involved in the mechanisms of allergen-specific immunotherapy. Several recent findings have suggested that silent internalization is strongly associated with FcεRI dynamics. A comprehensive understanding of the role of FcεRI may lead to the development of novel therapies for allergies. Here, we review the qualitatively diverse responses of MCs that impact the attenuation/development of allergies with a focus on the role of FcεRI toward Ag exposure.
Collapse
|
8
|
Temporal Modulation of Drug Desensitization Procedures. Curr Issues Mol Biol 2022; 44:833-844. [PMID: 35723342 PMCID: PMC8929139 DOI: 10.3390/cimb44020057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 01/28/2022] [Accepted: 01/30/2022] [Indexed: 11/17/2022] Open
Abstract
Drug hypersensitivity reactions are an unavoidable clinical consequence of the presence of new therapeutic agents. These adverse reactions concern patients afflicted with infectious diseases (e.g., hypersensitivity to antibiotics), and with non-infectious chronic diseases, such as in cancers, diabetes or cystic fibrosis treatments, and may occur at the first drug administration or after repeated exposures. Here we revise recent key studies on the mechanisms underlying the desensitization protocols, and propose an additional temporal regulation layer that is based on the circadian control of the signaling pathway involved and on the modulation of the memory effects established by the desensitization procedures.
Collapse
|
9
|
Kang SY, Seo J, Kang HR. Desensitization for the prevention of drug hypersensitivity reactions. Korean J Intern Med 2022; 37:261-270. [PMID: 35123386 PMCID: PMC8925949 DOI: 10.3904/kjim.2021.438] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/19/2021] [Indexed: 11/27/2022] Open
Abstract
Drug desensitization is the temporary induction of tolerance to a sensitized drug by administering slow increments of the drug, starting from a very small amount to a full therapeutic dose. It can be used as a therapeutic strategy for patients with drug hypersensitivity when no comparable alternatives are available. Desensitization has been recommended for immunoglobulin E (IgE)-mediated immediate hypersensitivity; however, its indications have recently been expanded to include non-IgE-mediated, non-immunological, or delayed T cell-mediated reactions. Currently, the mechanism of desensitization is not fully understood. However, the attenuation of various intracellular signals in target cells is an area of active research, such as high-affinity IgE receptor (FcεRI) internalization, anti-drug IgG4 blocking antibody, altered signaling pathways in mast cells and basophils, and reduced Ca2+ influx. Agents commonly requiring desensitization include antineoplastic agents, antibiotics, antituberculous agents, and aspirin/nonsteroidal antiinflammatory drugs. Various desensitization protocols (rapid or slow, multi-bag or one-bag, with different target doses) have been proposed for each drug. An appropriate protocol should be selected with the appropriate concentration, dosage, dosing interval, and route of administration. In addition, the protocol should be adjusted with consideration of the severity of the initial reaction, the characteristics of the drug itself, as well as the frequency, pattern, and degree of breakthrough reactions.
Collapse
Affiliation(s)
- Sung-Yoon Kang
- Department of Internal Medicine, Gachon University Gil Medical Center, Incheon,
Korea
| | - Jeongmin Seo
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul,
Korea
| | - Hye-Ryun Kang
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul,
Korea
- Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul National University College of Medicine, Seoul,
Korea
| |
Collapse
|
10
|
Arthur GK, Cruse G. Regulation of Trafficking and Signaling of the High Affinity IgE Receptor by FcεRIβ and the Potential Impact of FcεRIβ Splicing in Allergic Inflammation. Int J Mol Sci 2022; 23:ijms23020788. [PMID: 35054974 PMCID: PMC8776166 DOI: 10.3390/ijms23020788] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/06/2022] [Accepted: 01/08/2022] [Indexed: 12/23/2022] Open
Abstract
Mast cells are tissue-resident immune cells that function in both innate and adaptive immunity through the release of both preformed granule-stored mediators, and newly generated proinflammatory mediators that contribute to the generation of both the early and late phases of the allergic inflammatory response. Although mast cells can be activated by a vast array of mediators to contribute to homeostasis and pathophysiology in diverse settings and contexts, in this review, we will focus on the canonical setting of IgE-mediated activation and allergic inflammation. IgE-dependent activation of mast cells occurs through the high affinity IgE receptor, FcεRI, which is a multimeric receptor complex that, once crosslinked by antigen, triggers a cascade of signaling to generate a robust response in mast cells. Here, we discuss FcεRI structure and function, and describe established and emerging roles of the β subunit of FcεRI (FcεRIβ) in regulating mast cell function and FcεRI trafficking and signaling. We discuss current approaches to target IgE and FcεRI signaling and emerging approaches that could target FcεRIβ specifically. We examine how alternative splicing of FcεRIβ alters protein function and how manipulation of splicing could be employed as a therapeutic approach. Targeting FcεRI directly and/or IgE binding to FcεRI are promising approaches to therapeutics for allergic inflammation. The characteristic role of FcεRIβ in both trafficking and signaling of the FcεRI receptor complex, the specificity to IgE-mediated activation pathways, and the preferential expression in mast cells and basophils, makes FcεRIβ an excellent, but challenging, candidate for therapeutic strategies in allergy and asthma, if targeting can be realized.
Collapse
Affiliation(s)
- Greer K. Arthur
- Department of Population Health and Pathobiology, College of Veterinary Medicine, NC State University, Raleigh, NC 27607, USA;
| | - Glenn Cruse
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, NC State University, Raleigh, NC 27607, USA
- Correspondence: ; Tel.: +1-919-515-8865
| |
Collapse
|
11
|
McCarty MF, Lerner A, DiNicolantonio JJ, Benzvi C. Nutraceutical Aid for Allergies - Strategies for Down-Regulating Mast Cell Degranulation. J Asthma Allergy 2021; 14:1257-1266. [PMID: 34737578 PMCID: PMC8558634 DOI: 10.2147/jaa.s332307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/24/2021] [Indexed: 11/23/2022] Open
Abstract
Interactions of antigens with the mast cell FcεRI-IgE receptor complex induce degranulation and boost synthesis of pro-inflammatory lipid mediators and cytokines. Activation of spleen tyrosine kinase (Syk) functions as a central hub in this signaling. The tyrosine phosphatase SHP-1 opposes Syk activity; stimulation of NADPH oxidase by FcεRI activation results in the production of oxidants that reversibly inhibit SHP-1, up-regulating the signal from Syk. Activated AMPK can suppress Syk activation by the FcεRI receptor, possibly reflecting its ability to phosphorylate the FcεRI beta subunit. Cyclic GMP, via protein kinase G II, enhances the activity of SHP-1 by phosphorylating its C-terminal region; this may explain its inhibitory impact on mast cell activation. Hydrogen sulfide (H2S) likewise opposes mast cell activation; H2S can boost AMPK activity, up-regulate cGMP production, and trigger Nrf2-mediated induction of Phase 2 enzymes - including heme oxygenase-1, whose generation of bilirubin suppresses NADPH oxidase activity. Phycocyanobilin (PCB), a chemical relative of bilirubin, shares its inhibitory impact on NADPH oxidase, rationalizing reported anti-allergic effects of PCB-rich spirulina ingestion. Phase 2 inducer nutraceuticals can likewise oppose the up-regulatory impact of NADPH oxidase on FcεRI signaling. AMPK can be activated with the nutraceutical berberine. High-dose biotin can boost cGMP levels in mast cells via direct stimulation of soluble guanylate cyclase. Endogenous generation of H2S in mast cells can be promoted by administering N-acetylcysteine and likely by taurine, which increases the expression of H2S-producing enzymes in the vascular system. Mast cell stabilization by benifuuki green tea catechins may reflect the decreased surface expression of FcεRI.
Collapse
Affiliation(s)
| | - Aaron Lerner
- Chaim Sheba Medical Center, The Zabludowicz Research Center for Autoimmune Diseases, Tel Hashomer, Israel
| | - James J DiNicolantonio
- Saint Luke’s Mid America Heart Institute, Kansas City, MO, USA
- Advanced Ingredients for Dietary Products, AIDP, City of Industry, CA, USA
| | - Carina Benzvi
- Chaim Sheba Medical Center, The Zabludowicz Research Center for Autoimmune Diseases, Tel Hashomer, Israel
| |
Collapse
|
12
|
Sieber J, Renner S, Lakatos-Krepcik A, Szépfalusi Z. Case Report: Maintenance of Desensitization to Nebulized Colomycin Over 10 Years. Front Pediatr 2021; 9:663228. [PMID: 33869120 PMCID: PMC8049140 DOI: 10.3389/fped.2021.663228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/05/2021] [Indexed: 12/28/2022] Open
Abstract
Drug desensitization can be achieved successfully by gradual drug dose increases in different protocols. Most protocols are designed to obtain temporal tolerance. The data on long-term maintenance of drug tolerance is scarce. Based on an IgE-mediated colomycin allergy we describe the maintenance of drug tolerance to nebulized drug for the period of 10 years in a 15-year-old cystic fibrosis patient, proceeded by successful rush intravenous desensitization protocol. The mechanism of drug tolerance is largely speculative; however, long-term maintenance of it seems achievable by continuous local drug application.
Collapse
Affiliation(s)
- Justyna Sieber
- Division of Pediatric Pulmonology, Allergy and Endocrinology, Departement of Pediatrics and Adolescent Medicine, Comprehensive Center of Pediatrics, Medical University of Vienna, Vienna, Austria.,Department of Clinical Immunology, Wroclaw Medical University, Wroclaw, Poland
| | - Sabine Renner
- Division of Pediatric Pulmonology, Allergy and Endocrinology, Departement of Pediatrics and Adolescent Medicine, Comprehensive Center of Pediatrics, Medical University of Vienna, Vienna, Austria
| | | | - Zsolt Szépfalusi
- Division of Pediatric Pulmonology, Allergy and Endocrinology, Departement of Pediatrics and Adolescent Medicine, Comprehensive Center of Pediatrics, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
13
|
Mazhari A, Emanuele MA, Espiritu B. Desensitization to Methimazole. Endocr Pract 2020; 27:185-190. [PMID: 33779553 DOI: 10.1016/j.eprac.2020.10.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/11/2020] [Accepted: 10/18/2020] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Thionamides (methimazole and propylthiouracil) have been associated with common side effects, such as rash and pruritus, and rare but serious adverse effects, such as agranulocytosis and hepatotoxicity. Methimazole is usually the preferred thionamide for the treatment of hyperthyroidism if the patient is not planning to conceive or not in the first trimester of pregnancy, given the less frequent dosing and lower risk of hepatotoxicity. In patients who experience rash or itching when treated with methimazole, switching them to propylthiouracil is one treatment option. Here we report our experience regarding desensitization to methimazole to allow continued treatment with methimazole as an alternative management option. METHODS We conducted a retrospective chart review of patients at a single institution who had side effects to methimazole and who were desensitized to methimazole under the supervision of an allergist. A total of 7 patients were included who experienced side effects to methimazole that did not include agranulocytosis or hepatotoxicity. RESULTS All 7 patients were able to take methimazole for treatment of their hyperthyroidism, either for continued medical therapy or as a bridge to definitive therapy, with either surgery or radioactive iodine treatment. CONCLUSION Under the supervision of an allergist, desensitization to methimazole is an option for treating patients who experience side effects to methimazole (excluding agranulocytosis and hepatotoxicity).
Collapse
|
14
|
Neuhaus K, Wamhoff EC, Freichel T, Grafmüller A, Rademacher C, Hartmann L. Asymmetrically Branched Precision Glycooligomers Targeting Langerin. Biomacromolecules 2019; 20:4088-4095. [PMID: 31600054 DOI: 10.1021/acs.biomac.9b00906] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Asymmetrically branched precision glycooligomers are synthesized by solid-phase polymer synthesis for studying multivalent carbohydrate-protein interactions. Through the stepwise assembly of Fmoc-protected oligo(amidoamine) building blocks and Fmoc/Dde-protected lysine, straightforward variation of structural parameters such as the number and length of arms, as well as the number and position of carbohydrate ligands, is achieved. Binding of 1-arm and 3-arm glycooligomers toward lectin receptors langerin and concanavalin A (ConA) was evaluated where the smallest 3-arm glycooligomer shows the highest binding toward langerin, and stepwise elongation of one, two, or all three arms leads to decreased binding. When directly comparing binding toward langerin and ConA, we find that structural variation of the scaffold affects glycomimetic ligand binding differently for the different targets, indicating the potential to tune such ligands not only for their avidity but also for their selectivity toward different lectins.
Collapse
Affiliation(s)
- Kira Neuhaus
- Institute of Organic Chemistry and Macromolecular Chemistry , Heinrich-Heine-Universität Düsseldorf , Universitätsstr. 1 , 40225 Düsseldorf , Germany
| | - Eike-Christian Wamhoff
- Department of Biomolecular Systems , Max Planck Institute of Colloids and Interfaces , Am Mühlenberg 1 , 14424 Potsdam , Germany.,Department of Biology, Chemistry and Pharmacy , Freie Universität Berlin , Königin-Luise-Straße 28-30 , 14195 Berlin , Germany
| | - Tanja Freichel
- Institute of Organic Chemistry and Macromolecular Chemistry , Heinrich-Heine-Universität Düsseldorf , Universitätsstr. 1 , 40225 Düsseldorf , Germany
| | - Andrea Grafmüller
- Department of Theory and Bio-Systems , Max Planck Institute of Colloids and Interfaces , Am Mühlenberg 1 , 14424 Potsdam , Germany
| | - Christoph Rademacher
- Department of Biomolecular Systems , Max Planck Institute of Colloids and Interfaces , Am Mühlenberg 1 , 14424 Potsdam , Germany.,Department of Biology, Chemistry and Pharmacy , Freie Universität Berlin , Königin-Luise-Straße 28-30 , 14195 Berlin , Germany
| | - Laura Hartmann
- Institute of Organic Chemistry and Macromolecular Chemistry , Heinrich-Heine-Universität Düsseldorf , Universitätsstr. 1 , 40225 Düsseldorf , Germany
| |
Collapse
|
15
|
Bucaite G, Kang-Pettinger T, Moreira J, Gould HJ, James LK, Sutton BJ, McDonnell JM. Interplay between Affinity and Valency in Effector Cell Degranulation: A Model System with Polcalcin Allergens and Human Patient-Derived IgE Antibodies. THE JOURNAL OF IMMUNOLOGY 2019; 203:1693-1700. [PMID: 31462504 DOI: 10.4049/jimmunol.1900509] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/19/2019] [Indexed: 01/10/2023]
Abstract
An allergic reaction is rapidly generated when allergens bind and cross-link IgE bound to its receptor FcεRI on effector cells, resulting in cell degranulation and release of proinflammatory mediators. The extent of effector cell activation is linked to allergen affinity, oligomeric state, valency, and spacing of IgE-binding epitopes on the allergen. Whereas most of these observations come from studies using synthetic allergens, in this study we have used Timothy grass pollen allergen Phl p 7 and birch pollen allergen Bet v 4 to study these effects. Despite the high homology of these polcalcin family allergens, Phl p 7 and Bet v 4 display different binding characteristics toward two human patient-derived polcalcin-specific IgE Abs. We have used native polcalcin dimers and engineered multimeric allergens to test the effects of affinity and oligomeric state on IgE binding and effector cell activation. Our results indicate that polcalcin multimers are required to stimulate high levels of effector cell degranulation when using the humanized RBL-SX38 cell model and that multivalency can overcome the need for high-affinity interactions.
Collapse
Affiliation(s)
- Gintare Bucaite
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom
| | - Tara Kang-Pettinger
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom.,Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, United Kingdom; and
| | - Jorge Moreira
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom
| | - Hannah J Gould
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom
| | - Louisa K James
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom.,Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, United Kingdom
| | - Brian J Sutton
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom.,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom
| | - James M McDonnell
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom; .,Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London, London SE1 1UL, United Kingdom
| |
Collapse
|
16
|
Travers T, Kanagy WK, Mansbach RA, Jhamba E, Cleyrat C, Goldstein B, Lidke DS, Wilson BS, Gnanakaran S. Combinatorial diversity of Syk recruitment driven by its multivalent engagement with FcεRIγ. Mol Biol Cell 2019; 30:2331-2347. [PMID: 31216232 PMCID: PMC6743456 DOI: 10.1091/mbc.e18-11-0722] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 05/17/2019] [Accepted: 06/10/2019] [Indexed: 12/14/2022] Open
Abstract
Syk/Zap70 family kinases are essential for signaling via multichain immune-recognition receptors such as tetrameric (αβγ2) FcεRI. Syk activation is generally attributed to cis binding of its tandem SH2 domains to dual phosphotyrosines within FcεRIγ-ITAMs (immunoreceptor tyrosine-based activation motifs). However, the mechanistic details of Syk docking on γ homodimers are unresolved. Here, we estimate that multivalent interactions for WT Syk improve cis-oriented binding by three orders of magnitude. We applied molecular dynamics (MD), hybrid MD/worm-like chain polymer modeling, and live cell imaging to evaluate relative binding and signaling output for all possible cis and trans Syk-FcεRIγ configurations. Syk binding is likely modulated during signaling by autophosphorylation on Y130 in interdomain A, since a Y130E phosphomimetic form of Syk is predicted to lead to reduced helicity of interdomain A and alter Syk's bias for cis binding. Experiments in reconstituted γ-KO cells, whose γ subunits are linked by disulfide bonds, as well as in cells expressing monomeric ITAM or hemITAM γ-chimeras, support model predictions that short distances between γ ITAM pairs are required for trans docking. We propose that the full range of docking configurations improves signaling efficiency by expanding the combinatorial possibilities for Syk recruitment, particularly under conditions of incomplete ITAM phosphorylation.
Collapse
Affiliation(s)
- Timothy Travers
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - William K. Kanagy
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Rachael A. Mansbach
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Elton Jhamba
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Cedric Cleyrat
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Byron Goldstein
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Diane S. Lidke
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Bridget S. Wilson
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - S. Gnanakaran
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM 87545
| |
Collapse
|
17
|
Velappan N, Mahajan A, Naranjo L, Velappan P, Andrews N, Tiee N, Chakraborti S, Hemez C, Gaiotto T, Wilson B, Bradbury A. Selection and characterization of FcεRI phospho-ITAM specific antibodies. MAbs 2019; 11:1206-1218. [PMID: 31311408 PMCID: PMC6748597 DOI: 10.1080/19420862.2019.1632113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Post-translational modifications, such as the phosphorylation of tyrosines, are often the initiation step for intracellular signaling cascades. Pan-reactive antibodies against modified amino acids (e.g., anti-phosphotyrosine), which are often used to assay these changes, require isolation of the specific protein prior to analysis and do not identify the specific residue that has been modified (in the case that multiple amino acids have been modified). Phosphorylation state-specific antibodies (PSSAs) developed to recognize post-translational modifications within a specific amino acid sequence can be used to study the timeline of modifications during a signal cascade. We used the FcϵRI receptor as a model system to develop and characterize high-affinity PSSAs using phage and yeast display technologies. We selected three β-subunit antibodies that recognized: 1) phosphorylation of tyrosines Y218 or Y224; 2) phosphorylation of the Y228 tyrosine; and 3) phosphorylation of all three tyrosines. We used these antibodies to study the receptor activation timeline of FcϵR1 in rat basophilic leukemia cells (RBL-2H3) upon stimulation with DNP24-BSA. We also selected an antibody recognizing the N-terminal phosphorylation site of the γ-subunit (Y65) of the receptor and applied this antibody to evaluate receptor activation. Recognition patterns of these antibodies show different timelines for phosphorylation of tyrosines in both β and γ subunits. Our methodology provides a strategy to select antibodies specific to post-translational modifications and provides new reagents to study mast cell activation by the high-affinity IgE receptor, FcϵRI.
Collapse
Affiliation(s)
- Nileena Velappan
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Avanika Mahajan
- Department of Pathology, University of New Mexico School of Medicine , Albuquerque , NM , USA
| | | | - Priyanka Velappan
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Nasim Andrews
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Nicholas Tiee
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Subhendu Chakraborti
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Colin Hemez
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Tiziano Gaiotto
- Biosecurity and Public Health, Bioscience Division, Los Alamos National Laboratory , Los Alamos , NM , USA
| | - Bridget Wilson
- Department of Pathology, University of New Mexico School of Medicine , Albuquerque , NM , USA
| | | |
Collapse
|
18
|
Vargas AM, Mahajan A, Tille KS, Wilson BS, Mattison CP. Cross-reaction of recombinant termite (Coptotermes formosanus) tropomyosin with IgE from cockroach and shrimp allergic individuals. Ann Allergy Asthma Immunol 2018; 120:335-337. [PMID: 29508724 DOI: 10.1016/j.anai.2017.12.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/27/2017] [Accepted: 12/20/2017] [Indexed: 11/17/2022]
Affiliation(s)
- Aurora M Vargas
- Initiative for Maximizing Student Development, Louisiana State University, Baton Rouge, Louisiana
| | - Avanika Mahajan
- University of New Mexico, School of Medicine, Albuquerque, New Mexico
| | - Katherine S Tille
- Malcolm Grow Medical Clinics and Surgical Center, Joint Base Andrews, Maryland
| | - Bridget S Wilson
- University of New Mexico, School of Medicine, Albuquerque, New Mexico
| | - Christopher P Mattison
- US Department of Agriculture-Agricultural Research Service, Southern Regional Research Center, New Orleans, Louisiana.
| |
Collapse
|
19
|
Shahinuzzaman M, Khetan J, Barua D. A spatio-temporal model reveals self-limiting Fc ɛRI cross-linking by multivalent antigens. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180190. [PMID: 30839725 PMCID: PMC6170560 DOI: 10.1098/rsos.180190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 08/23/2018] [Indexed: 06/09/2023]
Abstract
Aggregation of cell surface receptor proteins by multivalent antigens is an essential early step for immune cell signalling. A number of experimental and modelling studies in the past have investigated multivalent ligand-mediated aggregation of IgE receptors (FcɛRI) in the plasma membrane of mast cells. However, understanding of the mechanisms of FcɛRI aggregation remains incomplete. Experimental reports indicate that FcɛRI forms relatively small and finite-sized clusters when stimulated by a multivalent ligand. By contrast, modelling studies have shown that receptor cross-linking by a trivalent ligand may lead to the formation of large receptor superaggregates that may potentially give rise to hyperactive cellular responses. In this work, we have developed a Brownian dynamics-based spatio-temporal model to analyse FcɛRI aggregation by a trivalent antigen. Unlike the existing models, which implemented non-spatial simulation approaches, our model explicitly accounts for the coarse-grained site-specific features of the multivalent species (molecules and complexes). The model incorporates membrane diffusion, steric collisions and sub-nanometre-scale site-specific interaction of the time-evolving species of arbitrary structures. Using the model, we investigated temporal evolution of the species and their diffusivities. Consistent with a recent experimental report, our model predicted sharp decay in species mobility in the plasma membrane in response receptor cross-linking by a multivalent antigen. We show that, due to such decay in the species mobility, post-stimulation receptor aggregation may become self-limiting. Our analysis reveals a potential regulatory mechanism suppressing hyperactivation of immune cells in response to multivalent antigens.
Collapse
Affiliation(s)
| | | | - Dipak Barua
- Author for correspondence: Dipak Barua e-mail:
| |
Collapse
|
20
|
Timescale Separation of Positive and Negative Signaling Creates History-Dependent Responses to IgE Receptor Stimulation. Sci Rep 2017; 7:15586. [PMID: 29138425 PMCID: PMC5686181 DOI: 10.1038/s41598-017-15568-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 10/26/2017] [Indexed: 02/02/2023] Open
Abstract
The high-affinity receptor for IgE expressed on the surface of mast cells and basophils interacts with antigens, via bound IgE antibody, and triggers secretion of inflammatory mediators that contribute to allergic reactions. To understand how past inputs (memory) influence future inflammatory responses in mast cells, a microfluidic device was used to precisely control exposure of cells to alternating stimulatory and non-stimulatory inputs. We determined that the response to subsequent stimulation depends on the interval of signaling quiescence. For shorter intervals of signaling quiescence, the second response is blunted relative to the first response, whereas longer intervals of quiescence induce an enhanced second response. Through an iterative process of computational modeling and experimental tests, we found that these memory-like phenomena arise from a confluence of rapid, short-lived positive signals driven by the protein tyrosine kinase Syk; slow, long-lived negative signals driven by the lipid phosphatase Ship1; and slower degradation of Ship1 co-factors. This work advances our understanding of mast cell signaling and represents a generalizable approach for investigating the dynamics of signaling systems.
Collapse
|
21
|
Shahinuzzaman MD, Barua D. A Multiscale Algorithm for Spatiotemporal Modeling of Multivalent Protein-Protein Interaction. J Comput Biol 2017; 24:1275-1283. [PMID: 29099235 DOI: 10.1089/cmb.2017.0178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This article introduces a multiscale framework for spatiotemporal modeling of protein-protein interaction. Cellular protein molecules represent multivalent species that contain modular features, such as binding domains and phosphorylation motifs. The binding and transformations of these features occur at a small time and spatial scale. On the other hand, space and time involved in protein diffusion, colocalization, and formation of complexes could be relatively large. Here, we present an agent-based framework integrated with a multiscale Brownian Dynamics (BD) simulation algorithm. The framework employs spatial graphs to describe multivalent molecules and complexes with their site-specific details. By implementing a time-adaptive feature, the BD algorithm enables efficient computation while capturing the site-specific interactions of the diffusing species at the sub-nanometer scale. We demonstrate these capabilities by modeling two multivalent molecules, one representing a ligand and the other a receptor, in a two-dimensional plane (cell membrane). Using the model, we show that the algorithm can accelerate computation by orders of magnitudes in both concentrated and dilute regimes. We also show that the algorithm enables robust model predictions against a wide range of selection of time step sizes.
Collapse
Affiliation(s)
- M D Shahinuzzaman
- Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology , Rolla, Missouri
| | - Dipak Barua
- Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology , Rolla, Missouri
| |
Collapse
|
22
|
Schwartz SL, Cleyrat C, Olah MJ, Relich PK, Phillips GK, Hlavacek WS, Lidke KA, Wilson BS, Lidke DS. Differential mast cell outcomes are sensitive to FcεRI-Syk binding kinetics. Mol Biol Cell 2017; 28:3397-3414. [PMID: 28855374 PMCID: PMC5687039 DOI: 10.1091/mbc.e17-06-0350] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/21/2017] [Accepted: 08/22/2017] [Indexed: 11/11/2022] Open
Abstract
Cross-linking of immunoglobulin E-bound FcεRI triggers multiple cellular responses, including degranulation and cytokine production. Signaling is dependent on recruitment of Syk via docking of its dual SH2 domains to phosphorylated tyrosines within the FcεRI immunoreceptor tyrosine-based activation motifs. Using single-molecule imaging in live cells, we directly visualized and quantified the binding of individual mNeonGreen-tagged Syk molecules as they associated with the plasma membrane after FcεRI activation. We found that Syk colocalizes transiently to FcεRI and that Syk-FcεRI binding dynamics are independent of receptor aggregate size. Substitution of glutamic acid for tyrosine between the Syk SH2 domains (Syk-Y130E) led to an increased Syk-FcεRI off-rate, loss of site-specific Syk autophosphorylation, and impaired downstream signaling. Genome edited cells expressing only Syk-Y130E were deficient in antigen-stimulated calcium release, degranulation, and production of some cytokines (TNF-a, IL-3) but not others (MCP-1, IL-4). We propose that kinetic discrimination along the FcεRI signaling pathway occurs at the level of Syk-FcεRI interactions, with key outcomes dependent upon sufficiently long-lived Syk binding events.
Collapse
Affiliation(s)
- Samantha L Schwartz
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Cédric Cleyrat
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Mark J Olah
- Department of Physics, University of New Mexico, Albuquerque, NM 87131
| | - Peter K Relich
- Department of Physics, University of New Mexico, Albuquerque, NM 87131
| | - Genevieve K Phillips
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - William S Hlavacek
- Theoretical Biology and Biophysics Group, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Keith A Lidke
- Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131.,Department of Physics, University of New Mexico, Albuquerque, NM 87131
| | - Bridget S Wilson
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131.,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| | - Diane S Lidke
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131 .,Comprehensive Cancer Center, University of New Mexico, Albuquerque, NM 87131
| |
Collapse
|
23
|
Deak PE, Vrabel MR, Kiziltepe T, Bilgicer B. Determination of Crucial Immunogenic Epitopes in Major Peanut Allergy Protein, Ara h2, via Novel Nanoallergen Platform. Sci Rep 2017; 7:3981. [PMID: 28638052 PMCID: PMC5479826 DOI: 10.1038/s41598-017-04268-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 05/10/2017] [Indexed: 12/16/2022] Open
Abstract
Current methods for detection and diagnosis of allergies do not provide epitope specific immunogenic information and hence lack critical information that could aid in the prediction of clinical responses. To address this issue, we developed a nanoparticle based platform, called nanoallergens that enable multivalent display of potential allergy epitopes for determining the immunogenicity of each IgE binding epitope. By synthesizing nanoallergens that present various epitopes from the major peanut allergen, Ara h2, we directly determined the immunogenicity of each epitope, alone and in combination with other epitopes, using patient sera. This information provided insights on which epitopes are most critical for physiological responses to Ara h2 and revealed the importance of both high and low affinity epitopes for allergic responses. We anticipate the nanoallergen platform to be used to provide information regarding allergic reactions and therefore potentially aid in more accurate diagnosis and design of personalized treatment options.
Collapse
Affiliation(s)
- Peter E Deak
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Maura R Vrabel
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Tanyel Kiziltepe
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA
- Advanced Diagnostics and Therapeutics, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Basar Bilgicer
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA.
- Advanced Diagnostics and Therapeutics, University of Notre Dame, Notre Dame, IN, 46556, USA.
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA.
| |
Collapse
|
24
|
de Las Vecillas Sánchez L, Alenazy LA, Garcia-Neuer M, Castells MC. Drug Hypersensitivity and Desensitizations: Mechanisms and New Approaches. Int J Mol Sci 2017; 18:E1316. [PMID: 28632196 PMCID: PMC5486137 DOI: 10.3390/ijms18061316] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/13/2017] [Accepted: 06/14/2017] [Indexed: 12/13/2022] Open
Abstract
Drug hypersensitivity reactions (HSRs) are increasing in the 21st Century with the ever expanding availability of new therapeutic agents. Patients with cancer, chronic inflammatory diseases, cystic fibrosis, or diabetes can become allergic to their first line therapy after repeated exposures or through cross reactivity with environmental allergens. Avoidance of the offending allergenic drug may impact disease management, quality of life, and life expectancy. Precision medicine provides new tools for the understanding and management of hypersensitivity reactions (HSRs), as well as a personalized treatment approach for IgE (Immunoglobuline E) and non-IgE mediated HSRs with drug desensitization (DS). DS induces a temporary hyporesponsive state by incremental escalation of sub-optimal doses of the offending drug. In vitro models have shown evidence that IgE desensitization is an antigen-specific process which blocks calcium flux, impacts antigen/IgE/FcεRI complex internalization and prevents the acute and late phase reactions as well as mast cell mediator release. Through a "bench to bedside" approach, in vitro desensitization models help elucidate the molecular pathways involved in DS, providing new insights to improved desensitization protocols for all patients. The aim of this review is to summarize up to date information on the drug HSRs, the IgE mediated mechanisms of desensitization, and their clinical applications.
Collapse
Affiliation(s)
- Leticia de Las Vecillas Sánchez
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
- Department of Allergy, Marqués de Valdecilla University Hospital-IDIVAL, 39011 Santander, Spain.
| | - Leila A Alenazy
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
- Department of Medicine, College of Medicine, King Saud University, Riyadh 12372, Saudi Arabia.
- Master of Medical Sciences in Immunology Program, Harvard Medical School, Boston, MA 02115, USA.
| | - Marlene Garcia-Neuer
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Mariana C Castells
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
25
|
Mahajan A, Youssef LA, Cleyrat C, Grattan R, Lucero SR, Mattison CP, Erasmus MF, Jacobson B, Tapia L, Hlavacek WS, Schuyler M, Wilson BS. Allergen Valency, Dose, and FcεRI Occupancy Set Thresholds for Secretory Responses to Pen a 1 and Motivate Design of Hypoallergens. THE JOURNAL OF IMMUNOLOGY 2016; 198:1034-1046. [PMID: 28039304 DOI: 10.4049/jimmunol.1601334] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 11/30/2016] [Indexed: 11/19/2022]
Abstract
Ag-mediated crosslinking of IgE-FcεRI complexes activates mast cells and basophils, initiating the allergic response. Of 34 donors recruited having self-reported shrimp allergy, only 35% had significant levels of shrimp-specific IgE in serum and measurable basophil secretory responses to rPen a 1 (shrimp tropomyosin). We report that degranulation is linked to the number of FcεRI occupied with allergen-specific IgE, as well as the dose and valency of Pen a 1. Using clustered regularly interspaced palindromic repeat-based gene editing, human RBLrαKO cells were created that exclusively express the human FcεRIα subunit. Pen a 1-specific IgE was affinity purified from shrimp-positive plasma. Cells primed with a range of Pen a 1-specific IgE and challenged with Pen a 1 showed a bell-shaped dose response for secretion, with optimal Pen a 1 doses of 0.1-10 ng/ml. Mathematical modeling provided estimates of receptor aggregation kinetics based on FcεRI occupancy with IgE and allergen dose. Maximal degranulation was elicited when ∼2700 IgE-FcεRI complexes were occupied with specific IgE and challenged with Pen a 1 (IgE epitope valency of ≥8), although measurable responses were achieved when only a few hundred FcεRI were occupied. Prolonged periods of pepsin-mediated Pen a 1 proteolysis, which simulates gastric digestion, were required to diminish secretory responses. Recombinant fragments (60-79 aa), which together span the entire length of tropomyosin, were weak secretagogues. These fragments have reduced dimerization capacity, compete with intact Pen a 1 for binding to IgE-FcεRI complexes, and represent a starting point for the design of promising hypoallergens for immunotherapy.
Collapse
Affiliation(s)
- Avanika Mahajan
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Lama A Youssef
- Department of Pharmaceutics and Pharmaceutical Technology, School of Pharmacy, Damascus University, Damascus, Syria.,National Commission for Biotechnology, Damascus, Syria
| | - Cédric Cleyrat
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Rachel Grattan
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Shayna R Lucero
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Christopher P Mattison
- Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, New Orleans, LA 70124
| | - M Frank Erasmus
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131
| | - Bruna Jacobson
- Department of Computer Sciences, University of New Mexico, Albuquerque, NM 87131
| | - Lydia Tapia
- Department of Computer Sciences, University of New Mexico, Albuquerque, NM 87131
| | - William S Hlavacek
- Theoretical Biology and Biophysics Group, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545.,Theoretical Biology and Biophysics Group, Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545; and
| | - Mark Schuyler
- Department of Medicine, University of New Mexico, Albuquerque, NM 87131
| | - Bridget S Wilson
- Department of Pathology, University of New Mexico, Albuquerque, NM 87131;
| |
Collapse
|
26
|
Getahun A, Cambier JC. Of ITIMs, ITAMs, and ITAMis: revisiting immunoglobulin Fc receptor signaling. Immunol Rev 2016; 268:66-73. [PMID: 26497513 DOI: 10.1111/imr.12336] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Receptors for immunoglobulin Fc regions play multiple critical roles in the immune system, mediating functions as diverse as phagocytosis, triggering degranulation of basophils and mast cells, promoting immunoglobulin class switching, and preventing excessive activation. Transmembrane signaling associated with these functions is mediated primarily by two amino acid sequence motifs, ITAMs (immunoreceptor tyrosine-based activation motifs) and ITIMs (immunoreceptor tyrosine-based inhibition motifs) that act as the receptors' interface with activating and inhibitory signaling pathways, respectively. While ITAMs mobilize activating tyrosine kinases and their consorts, ITIMs mobilize opposing tyrosine and inositol-lipid phosphatases. In this review, we will discuss our current understanding of signaling by these receptors/motifs and their sometimes blurred lines of function.
Collapse
Affiliation(s)
- Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, USA
| |
Collapse
|
27
|
Hoard B, Jacobson B, Manavi K, Tapia L. Extending rule-based methods to model molecular geometry and 3D model resolution. BMC SYSTEMS BIOLOGY 2016; 10 Suppl 2:48. [PMID: 27490268 PMCID: PMC4977479 DOI: 10.1186/s12918-016-0294-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Computational modeling is an important tool for the study of complex biochemical processes associated with cell signaling networks. However, it is challenging to simulate processes that involve hundreds of large molecules due to the high computational cost of such simulations. Rule-based modeling is a method that can be used to simulate these processes with reasonably low computational cost, but traditional rule-based modeling approaches do not include details of molecular geometry. The incorporation of geometry into biochemical models can more accurately capture details of these processes, and may lead to insights into how geometry affects the products that form. Furthermore, geometric rule-based modeling can be used to complement other computational methods that explicitly represent molecular geometry in order to quantify binding site accessibility and steric effects. RESULTS We propose a novel implementation of rule-based modeling that encodes details of molecular geometry into the rules and binding rates. We demonstrate how rules are constructed according to the molecular curvature. We then perform a study of antigen-antibody aggregation using our proposed method. We simulate the binding of antibody complexes to binding regions of the shrimp allergen Pen a 1 using a previously developed 3D rigid-body Monte Carlo simulation, and we analyze the aggregate sizes. Then, using our novel approach, we optimize a rule-based model according to the geometry of the Pen a 1 molecule and the data from the Monte Carlo simulation. We use the distances between the binding regions of Pen a 1 to optimize the rules and binding rates. We perform this procedure for multiple conformations of Pen a 1 and analyze the impact of conformation and resolution on the optimal rule-based model. CONCLUSIONS We find that the optimized rule-based models provide information about the average steric hindrance between binding regions and the probability that antibodies will bind to these regions. These optimized models quantify the variation in aggregate size that results from differences in molecular geometry and from model resolution.
Collapse
Affiliation(s)
- Brittany Hoard
- Department of Computer Science, University of New Mexico, Albuquerque, 87131, New Mexico, USA
| | - Bruna Jacobson
- Department of Computer Science, University of New Mexico, Albuquerque, 87131, New Mexico, USA
| | - Kasra Manavi
- Department of Computer Science, University of New Mexico, Albuquerque, 87131, New Mexico, USA
| | - Lydia Tapia
- Department of Computer Science, University of New Mexico, Albuquerque, 87131, New Mexico, USA.
| |
Collapse
|
28
|
Abstract
SUMMARYIt is estimated that allergies afflict up to 40% of the world's population. A primary mediator for allergies is the aggregation of antigens and IgE antibodies bound to cell-surface receptors, FcεRI. Antibody/antigen aggregate formation causes stimulation of mast cells and basophils, initiating cellular degranulation and releasing immune mediators which produce an allergic or anaphylactic response. Understanding the shape and structure of these aggregates can provide critical insights into the allergic response. We have previously developed methods to geometrically model, simulate and analyze antibody aggregation inspired by rigid body robotic motion simulations. Our technique handles the large size and number of molecules involved in aggregation, providing an advantage over traditional simulations such as molecular dynamics (MD) and coarse-grained energetic models. In this paper, we study the impact of model resolution on simulations of geometric structures using both our previously developed Monte Carlo simulation and a novel application of rule-based modeling. These methods complement each other, the former providing explicit geometric detail and the latter providing a generic representation where multiple resolutions can be captured. Our exploration is focused on two antigens, a man-made antigen with three binding sites, DF3, and a common shrimp allergen (antigen), Pen a 1. We find that impact of resolution is minimal for DF3, a small globular antigen, but has a larger impact on Pen a 1, a rod-shaped molecule. The volume reduction caused by the loss in resolution allows more binding site accessibility, which can be quantified using a rule-based model with implicit geometric input. Clustering analysis of our simulation shows good correlation when compared with available experimental results. Moreover, collisions in all-atom reconstructions are negligible, at around 0.2% at 90% reduction.
Collapse
|
29
|
Deak PE, Vrabel MR, Pizzuti VJ, Kiziltepe T, Bilgicer B. Nanoallergens: A multivalent platform for studying and evaluating potency of allergen epitopes in cellular degranulation. Exp Biol Med (Maywood) 2016; 241:996-1006. [PMID: 27188517 DOI: 10.1177/1535370216644533] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Degranulation caused by type I hypersensitivity (allergies) is a complex biophysical process, and available experimental models for studying relevant immunoglobulin E binding epitopes on allergen proteins lack the ability to adequately evaluate, rank, and associate these epitopes individually and with each other. In this study, we propose a new allergy model system for studying potential allergen epitopes using nanoallergens, liposomes modified to effectively display IgE binding epitopes/haptens. By utilizing the covalently conjugated lipid tails on two hapten molecules (dinitrophenol and dansyl), hapten molecules were successfully incorporated into liposomes with high precision to form nanoallergens. Nanoallergens, with precisely controlled high-particle valency, can trigger degranulation with much greater sensitivity than commonly used bovine serum albumin conjugates. In rat basophil leukemia cell experiments, nanoallergens with only 2% hapten loading were able to trigger degranulation in vitro at concentrations as low as 10 pM. Additionally, unlike bovine serum albumin-hapten conjugates, nanoallergens allow exact control over particle size and valency. By varying the nanoallergen parameters such as size, valency, monovalent affinity of hapten, and specific IgE ratios, we exposed the importance of these variables on degranulation intensity while demonstrating nanoallergens' potential for evaluating both high- and low-affinity epitopes. The data presented in this article establish nanoallergen platform as a reliable and versatile allergy model to study and evaluate allergen epitopes in mast cell degranulation.
Collapse
Affiliation(s)
- Peter E Deak
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA
| | - Maura R Vrabel
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA
| | - Vincenzo J Pizzuti
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA
| | - Tanyel Kiziltepe
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA Advanced Diagnostics and Therapeutics, University of Notre Dame, IN 46556, USA
| | - Basar Bilgicer
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, IN 46556, USA Advanced Diagnostics and Therapeutics, University of Notre Dame, IN 46556, USA Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556, USA
| |
Collapse
|
30
|
Hoffmann HJ. News in Cellular Allergology: A Review of the Human Mast Cell and Basophil Granulocyte Literature from January 2013 to May 2015. Int Arch Allergy Immunol 2016; 168:253-62. [DOI: 10.1159/000443960] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
31
|
Phong BL, Avery L, Sumpter TL, Gorman JV, Watkins SC, Colgan JD, Kane LP. Tim-3 enhances FcεRI-proximal signaling to modulate mast cell activation. J Exp Med 2015; 212:2289-304. [PMID: 26598760 PMCID: PMC4689164 DOI: 10.1084/jem.20150388] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 10/21/2015] [Indexed: 12/24/2022] Open
Abstract
Phong et al. show that depending on the expression of p-Lyn, mast cell activation by antigen can result in dichotomous effects on mast cell function and signaling that can be accentuated by Tim-3 ligation. T cell (or transmembrane) immunoglobulin and mucin domain protein 3 (Tim-3) has attracted significant attention as a novel immune checkpoint receptor (ICR) on chronically stimulated, often dysfunctional, T cells. Antibodies to Tim-3 can enhance antiviral and antitumor immune responses. Tim-3 is also constitutively expressed by mast cells, NK cells and specific subsets of macrophages and dendritic cells. There is ample evidence for a positive role for Tim-3 in these latter cell types, which is at odds with the model of Tim-3 as an inhibitory molecule on T cells. At this point, little is known about the molecular mechanisms by which Tim-3 regulates the function of T cells or other cell types. We have focused on defining the effects of Tim-3 ligation on mast cell activation, as these cells constitutively express Tim-3 and are activated through an ITAM-containing receptor for IgE (FcεRI), using signaling pathways analogous to those in T cells. Using a variety of gain- and loss-of-function approaches, we find that Tim-3 acts at a receptor-proximal point to enhance Lyn kinase-dependent signaling pathways that modulate both immediate-phase degranulation and late-phase cytokine production downstream of FcεRI ligation.
Collapse
Affiliation(s)
- Binh L Phong
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261 Graduate Program in Immunology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Lyndsay Avery
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261 Infectious Disease and Microbiology Graduate Program, University of Pittsburgh, Pittsburgh, PA 15261
| | - Tina L Sumpter
- Department of Dermatology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Jacob V Gorman
- Interdisciplinary Graduate Program in Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261
| | - John D Colgan
- Interdisciplinary Graduate Program in Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242 Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| | - Lawrence P Kane
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261
| |
Collapse
|
32
|
Chylek LA, Harris LA, Faeder JR, Hlavacek WS. Modeling for (physical) biologists: an introduction to the rule-based approach. Phys Biol 2015; 12:045007. [PMID: 26178138 PMCID: PMC4526164 DOI: 10.1088/1478-3975/12/4/045007] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Models that capture the chemical kinetics of cellular regulatory networks can be specified in terms of rules for biomolecular interactions. A rule defines a generalized reaction, meaning a reaction that permits multiple reactants, each capable of participating in a characteristic transformation and each possessing certain, specified properties, which may be local, such as the state of a particular site or domain of a protein. In other words, a rule defines a transformation and the properties that reactants must possess to participate in the transformation. A rule also provides a rate law. A rule-based approach to modeling enables consideration of mechanistic details at the level of functional sites of biomolecules and provides a facile and visual means for constructing computational models, which can be analyzed to study how system-level behaviors emerge from component interactions.
Collapse
Affiliation(s)
- Lily A Chylek
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
- Theoretical Biology and Biophysics Group, Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Leonard A Harris
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37212, USA
| | - James R Faeder
- Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - William S Hlavacek
- Theoretical Biology and Biophysics Group, Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
- New Mexico Consortium, Los Alamos, NM 87544, USA
| |
Collapse
|