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Zeng L, Yang K, Wu Y, Yu G, Yan Y, Hao M, Song T, Li Y, Chen J, Sun L. Telitacicept: A novel horizon in targeting autoimmunity and rheumatic diseases. J Autoimmun 2024; 148:103291. [PMID: 39146891 DOI: 10.1016/j.jaut.2024.103291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 06/19/2024] [Accepted: 07/15/2024] [Indexed: 08/17/2024]
Abstract
BLyS and APRIL have the capability to bind to B cells within the body, allowing these cells to evade elimination when they should naturally be removed. While BLyS primarily plays a role in B cell development and maturation, APRIL is linked to B cell activation and the secretion of antibodies. Thus, in theory, inhibiting BLyS or APRIL could diminish the population of aberrant B cells that contribute to SLE and reduce disease activity in patients. Telitacicept functions by binding to and neutralizing the activities of both BLyS and APRIL, thus hindering the maturation and survival of plasma cells and fully developed B cells. The design of telitacicept is distinctive; it is not a monoclonal antibody but a TACI-Fc fusion protein generated through recombinant DNA technology. This fusion involves merging gene segments of the TACI protein, which can target BLyS/APRIL simultaneously, with the Fc gene segment of the human IgG protein. The TACI-Fc fusion protein exhibits the combined characteristics of both proteins. Currently utilized for autoimmune disease treatment, telitacicept is undergoing clinical investigations globally to assess its efficacy in managing various autoimmune conditions. This review consolidates information on the mechanistic actions, dosing regimens, pharmacokinetics, efficacy, and safety profile of telitacicept-a dual-targeted biological agent. It integrates findings from prior experiments and pharmacokinetic analyses in the treatment of RA and SLE, striving to offer a comprehensive overview of telitacicept's research advancements.
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Affiliation(s)
- Liuting Zeng
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Graduate School of Peking Union Medical College, Nanjing, China.
| | - Kailin Yang
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, School of Integrated Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha, China; Psychosomatic laboratory, Department of Psychiatry, Daqing Hospital of Traditional Chinese Medicine, Daqing, China.
| | - Yang Wu
- Department of Rheumatology, National Clinical Research Center for Dermatologic and Immunologic Diseases, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Ganpeng Yu
- People's Hospital of Ningxiang City, Ningxiang, China
| | - Yexing Yan
- Psychosomatic laboratory, Department of Psychiatry, Daqing Hospital of Traditional Chinese Medicine, Daqing, China
| | - Moujia Hao
- Psychosomatic laboratory, Department of Psychiatry, Daqing Hospital of Traditional Chinese Medicine, Daqing, China
| | - Tian Song
- Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yuwei Li
- School of Mathematics and Computational Science, Hunan University of Science and Technology, Hunan, China
| | - Junpeng Chen
- Department of Physiology, School of Medicine, University of Louisville, Kentucky, USA; Psychosomatic laboratory, Department of Psychiatry, Daqing Hospital of Traditional Chinese Medicine, Daqing, China; Tong Jiecheng Studio, Hunan University of Science and Technology, Xiangtan, China.
| | - Lingyun Sun
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Graduate School of Peking Union Medical College, Nanjing, China; Department of Rheumatology and Immunology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.
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Mariette X, Barone F, Baldini C, Bootsma H, Clark KL, De Vita S, Gardner DH, Henderson RB, Herdman M, Lerang K, Mistry P, Punwaney R, Seror R, Stone J, van Daele PL, van Maurik A, Wisniacki N, Roth DA, Tak PP. A randomized, phase II study of sequential belimumab and rituximab in primary Sjögren's syndrome. JCI Insight 2022; 7:e163030. [PMID: 36477362 PMCID: PMC9746921 DOI: 10.1172/jci.insight.163030] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/26/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUNDPrimary Sjögren's syndrome (pSS) is characterized by B cell hyperactivity and elevated B-lymphocyte stimulator (BLyS). Anti-BLyS treatment (e.g., belimumab) increases peripheral memory B cells; decreases naive, activated, and plasma B cell subsets; and increases stringency on B cell selection during reconstitution. Anti-CD20 therapeutics (e.g., rituximab) bind and deplete CD20-expressing B cells in circulation but are less effective in depleting tissue-resident CD20+ B cells. Combined, these 2 mechanisms may achieve synergistic effects.METHODSThis 68-week, phase II, double-blind study (GSK study 201842) randomized 86 adult patients with active pSS to 1 of 4 arms: placebo, s.c. belimumab, i.v. rituximab, or sequential belimumab + rituximab.RESULTSOverall, 60 patients completed treatment and follow-up until week 68. The incidence of adverse events (AEs) and drug-related AEs was similar across groups. Infections/infestations were the most common AEs, and no serious infections of special interest occurred. Near-complete depletion of minor salivary gland CD20+ B cells and a greater and more sustained depletion of peripheral CD19+ B cells were observed with belimumab + rituximab versus monotherapies. With belimumab + rituximab, reconstitution of peripheral B cells occurred, but it was delayed compared with rituximab. At week 68, mean (± standard error) total EULAR Sjögren's syndrome disease activity index scores decreased from 11.0 (1.17) at baseline to 5.0 (1.27) for belimumab + rituximab and 10.4 (1.36) to 8.6 (1.57) for placebo.CONCLUSIONThe safety profile of belimumab + rituximab in pSS was consistent with the monotherapies. Belimumab + rituximab induced enhanced salivary gland B cell depletion relative to the monotherapies, potentially leading to improved clinical outcomes.TRIAL REGISTRATIONClinicalTrials.gov NCT02631538.FUNDINGFunding was provided by GSK.
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Affiliation(s)
- Xavier Mariette
- Department of Rheumatology, Université Paris-Saclay, Hôpital Bicêtre, Assistance Publique — Hôpitaux de Paris, INSERM UMR1184, Le Kremlin Bicêtre, Paris, France
| | - Francesca Barone
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Chiara Baldini
- Centro Farmacologia Clinica AOUP, Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Hendrika Bootsma
- Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | | | - Salvatore De Vita
- Rheumatology Clinic, Department of Medical Area, Azienda Ospedaliera Universitaria di Udine, Udine, Italy
| | - David H. Gardner
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Robert B. Henderson
- Clinical Pharmacology and Experimental Medicine, GSK, Stevenage, Hertfordshire, United Kingdom
| | - Michael Herdman
- Clinical Pharmacology and Experimental Medicine, GSK, Stevenage, Hertfordshire, United Kingdom
| | - Karoline Lerang
- Department of Rheumatology, Oslo University Hospital, Oslo, Norway
| | - Prafull Mistry
- R&D Biostatistics, GSK, Stevenage, Hertfordshire, United Kingdom
| | - Raj Punwaney
- Pharmaceutical Research and Development, GSK, Collegeville, Pennsylvania, USA
| | - Raphaele Seror
- Department of Rheumatology, Université Paris-Saclay, Hôpital Bicêtre, Assistance Publique — Hôpitaux de Paris, INSERM UMR1184, Le Kremlin Bicêtre, Paris, France
| | - John Stone
- R&D, GSK, Stevenage, Hertfordshire, United Kingdom
| | - Paul L.A. van Daele
- Department of Internal Medicine and Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - André van Maurik
- Clinical Pharmacology and Experimental Medicine, GSK, Stevenage, Hertfordshire, United Kingdom
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Ramwadhdoebe TH, van Baarsen LGM, Boumans MJH, Bruijnen STG, Safy M, Berger FH, Semmelink JF, van der Laken CJ, Gerlag DM, Thurlings RM, Tak PP. Effect of rituximab treatment on T and B cell subsets in lymph node biopsies of patients with rheumatoid arthritis. Rheumatology (Oxford) 2020; 58:1075-1085. [PMID: 30649469 PMCID: PMC6532448 DOI: 10.1093/rheumatology/key428] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 11/21/2018] [Indexed: 11/25/2022] Open
Abstract
Objectives The exact underlying mechanism of rituximab treatment in patients with RA is poorly defined and knowledge about the effect of B cell depletion on immune cells in secondary lymphoid organs is lacking. We analysed lymphoid tissue responses to rituximab in RA patients. Methods Fourteen RA patients received 2 × 1000 mg rituximab intravenously, and lymph node (LN) biopsies were obtained before and 4 weeks after the first infusion. Tissues were examined by flow cytometry, immunohistochemistry and quantitative PCR. LN biopsies from five healthy individuals (HC) served as controls. Results LN biopsies of RA patients showed increased frequencies of CD21+CD23+IgDhighIgMvariable follicular B cells and CD3+CD25+CD69+ early activated, tissue resident T cells when compared with HCs. After treatment, there was incomplete depletion of LN B cells. There was a significant decrease in CD27−IgD+ naïve B cells, and CD27+IgD+ unswitched memory B cells including the CD27+IgD+IgM+ subset and follicular B cells. Strikingly, CD27+IgD− switched memory B cells persisted in LN biopsies after rituximab treatment. In the T cell compartment, a significant decrease was observed in the frequency of early activated, tissue resident T cells after rituximab treatment, but late activated T cells persisted. B cell proliferation inducing cytokine IL-21 was higher expressed in LN biopsies of RA patients compared with HC and expression was not affected by rituximab treatment. Conclusion Rituximab does not cure RA, possibly due to persistence of switched memory B cells in lymphoid tissues suggesting that factors promoting B cell survival and differentiation need to be additionally targeted.
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Affiliation(s)
- Tamara H Ramwadhdoebe
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands.,Department of Experimental Immunology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, University of Amsterdam, Netherlands
| | - Lisa G M van Baarsen
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands.,Department of Experimental Immunology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, University of Amsterdam, Netherlands
| | - Maria J H Boumans
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands
| | - Stefan T G Bruijnen
- Department of Rheumatology and Clinical Immunology, ARC, Amsterdam UMC, Vrije Universiteit Amsterdam, Netherlands
| | - Mary Safy
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands
| | - Ferco H Berger
- Department of Radiology & Nuclear Medicine, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Johanna F Semmelink
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands.,Department of Experimental Immunology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, University of Amsterdam, Netherlands
| | - Conny J van der Laken
- Department of Rheumatology and Clinical Immunology, ARC, Amsterdam UMC, Vrije Universiteit Amsterdam, Netherlands
| | - Danielle M Gerlag
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands.,Clinical Unit Cambridge, GlaxoSmithKline, UK
| | - Rogier M Thurlings
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands
| | - Paul P Tak
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center (ARC), Netherlands.,University of Cambridge, Cambridge, UK.,Ghent University, Ghent, Belgium
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Bensalem A, Mulleman D, Thibault G, Azzopardi N, Goupille P, Paintaud G, Ternant D. CD4+ count-dependent concentration-effect relationship of rituximab in rheumatoid arthritis. Br J Clin Pharmacol 2019; 85:2747-2758. [PMID: 31454097 DOI: 10.1111/bcp.14102] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/29/2019] [Accepted: 08/13/2019] [Indexed: 01/14/2023] Open
Abstract
AIMS Rituximab is approved in rheumatoid arthritis (RA). A substantial decrease in CD4+ count was observed in responders after a single cycle of treatment. This study aimed to describe and quantifying the influence of CD4+ count depletion on the concentration-response relationship of rituximab in RA patients. METHODS In this retrospective monocentric observational study, 52 patients were assessed. Repeated measurements of rituximab concentrations (pharmacokinetics), CD4+ counts (biomarker) and disease activity score in 28 joints (DAS28, clinical response) were made. Rituximab pharmacokinetics was described using a 2-compartment model, and CD4+ cell counts and DAS28 measurements were described using indirect turnover and direct Emax pharmacokinetic-pharmacodynamic models, respectively. Delay between rituximab concentrations and responses was accounted for by including biophase compartments. RESULTS Elimination half-life of rituximab was 18 days. The pharmacokinetic-pharmacodynamic model showed that DAS28 response to rituximab was partly associated with CD4+ cell depletion. At 6 months, a deeper DAS28 decrease was observed in patients when CD4+ cell count is decreased: median [interquartile range] of DAS28 was 3.7 [2.9-4.4] and 4.5 [3.7-5.3] in patients with and without CD4+ decrease, respectively. CONCLUSIONS This is the first study to quantify the relationship between rituximab concentrations, CD4+ count and DAS28 in RA patients. This model showed that approximately 75% of patients had CD4+ count decrease, and that the clinical improvement is 2-fold higher in patients with CD4+ cells decrease than in others.
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Affiliation(s)
| | - Denis Mulleman
- EA 7501 GICC, Université de Tours, Tours, France.,Department of Rheumatology, CHRU de Tours, Tours, France
| | - Gilles Thibault
- EA 7501 GICC, Université de Tours, Tours, France.,Laboratory of Immunology, CHRU de Tours, Tours, France.,ERL 7001, CNRS, Tours, France
| | - Nicolas Azzopardi
- EA 7501 GICC, Université de Tours, Tours, France.,ERL 7001, CNRS, Tours, France
| | - Philippe Goupille
- EA 7501 GICC, Université de Tours, Tours, France.,Department of Rheumatology, CHRU de Tours, Tours, France
| | - Gilles Paintaud
- EA 7501 GICC, Université de Tours, Tours, France.,Department of Medical Pharmacology, CHRU de Tours, Tours, France
| | - David Ternant
- EA 7501 GICC, Université de Tours, Tours, France.,Department of Medical Pharmacology, CHRU de Tours, Tours, France
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Pollastro S, Klarenbeek PL, Doorenspleet ME, van Schaik BDC, Esveldt REE, Thurlings RM, Boumans MJH, Gerlag DM, Tak PP, Vos K, Baas F, van Kampen AHC, de Vries N. Non-response to rituximab therapy in rheumatoid arthritis is associated with incomplete disruption of the B cell receptor repertoire. Ann Rheum Dis 2019; 78:1339-1345. [PMID: 31217169 PMCID: PMC6788876 DOI: 10.1136/annrheumdis-2018-214898] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To gain more insight into the dynamics of lymphocyte depletion and develop new predictors of clinical response to rituximab in rheumatoid arthritis (RA). METHODS RNA-based next-generation sequencing was used to analyse the B cell receptor (BCR) repertoire in peripheral blood and synovial tissue samples collected from 24 seropositive patients with RA treated with rituximab. Clonal expansion, mutation load and clonal overlap were assessed in samples collected before, at week 4 and at week 16 or 24 after treatment and correlated to the patients' clinical response. RESULTS After 4 weeks of rituximab-induced B cell depletion, the peripheral blood BCR repertoire of treated patients consisted of fewer, more dominant and more mutated BCR clones. No significant changes in the synovial tissue BCR repertoire were detected until week 16 post-treatment, when a reduced clonal overlap with baseline and an increased mutation load were observed. In patients who were non-responders at month 3 (n=5) using the European League Against Rheumatism response criteria, peripheral blood samples taken at week 4 after rituximab treatment showed more dominant clones compared with moderate responders (n=9) (median (IQR): 36 (27-52) vs 18 (16-26); p<0.01) and more clonal overlap with the baseline (median (IQR): 5% (2%-20%) vs 0% (0%-0%); p≤0.01). CONCLUSION Significant changes in BCR clonality are observed in peripheral blood of patients 4 weeks after rituximab treatment, while changes in synovial tissue were observed at later time points. Incomplete depletion of the dominant baseline peripheral blood BCR repertoire in the first month of treatment might predict clinical non-response at 3 months.
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Affiliation(s)
- Sabrina Pollastro
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands.,Department of Experimental Immunology
- Amsterdam Infection & Immunity Institute, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Paul L Klarenbeek
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Marieke E Doorenspleet
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Barbera D C van Schaik
- Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health Research Institute, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Rebecca E E Esveldt
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Rogier M Thurlings
- Department of Rheumatology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Maria J H Boumans
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Danielle M Gerlag
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands.,Clinical Unit Cambridge, GlaxoSmithKline, Cambridge, UK
| | - Paul P Tak
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medicine, Cambridge University, Cambridge, Massachusetts, USA.,Department of Rheumatology, Ghent University, Ghent, Belgium.,Flagship Pioneering, Cambridge, Massachusetts, USA
| | - Koen Vos
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Frank Baas
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands.,Laboratory for Diagnostic Genome Analysis, Leiden University Medical Center, Leiden, The Netherlands
| | - Antoine H C van Kampen
- Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Public Health Research Institute, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Niek de Vries
- Amsterdam Rheumatology and Immunology Center (ARC)
- Department of Clinical Immunology and Rheumatology, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands .,Department of Experimental Immunology
- Amsterdam Infection & Immunity Institute, Amsterdam UMC, location AMC, University of Amsterdam, Amsterdam, The Netherlands
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Schnute ME, Benoit SE, Buchler IP, Caspers N, Grapperhaus ML, Han S, Hotchandani R, Huang N, Hughes RO, Juba BM, Kim KH, Liu E, McCarthy E, Messing D, Miyashiro JS, Mohan S, O’Connell TN, Ohren JF, Parikh MD, Schmidt M, Selness SR, Springer JR, Thanabal V, Trujillo JI, Walker DP, Wan ZK, Withka JM, Wittwer AJ, Wood NL, Xing L, Zapf CW, Douhan J. Aminopyrazole Carboxamide Bruton's Tyrosine Kinase Inhibitors. Irreversible to Reversible Covalent Reactive Group Tuning. ACS Med Chem Lett 2019; 10:80-85. [PMID: 30655951 DOI: 10.1021/acsmedchemlett.8b00461] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/03/2018] [Indexed: 12/14/2022] Open
Abstract
Potent covalent inhibitors of Bruton's tyrosine kinase (BTK) based on an aminopyrazole carboxamide scaffold have been identified. Compared to acrylamide-based covalent reactive groups leading to irreversible protein adducts, cyanamide-based reversible-covalent inhibitors provided the highest combined BTK potency and EGFR selectivity. The cyanamide covalent mechanism with BTK was confirmed through enzyme kinetic, NMR, MS, and X-ray crystallographic studies. The lead cyanamide-based inhibitors demonstrated excellent kinome selectivity and rat pharmacokinetic properties.
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Affiliation(s)
| | | | | | - Nicole Caspers
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
| | | | - Seungil Han
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
| | | | | | | | | | | | | | | | | | | | | | | | - Jeffrey F. Ohren
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
| | - Mihir D. Parikh
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
| | | | | | | | | | - John I. Trujillo
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
| | | | | | - Jane M. Withka
- Medicine Design, Pfizer, Groton, Connecticut 06340, United States
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Nayar S, Campos J, Smith CG, Iannizzotto V, Gardner DH, Colafrancesco S, Pipi E, Kollert F, Hunter KJ, Brewer C, Buckley CD, Bowman SJ, Priori R, Valesini G, Juarez M, Fahy WA, Fisher BA, Payne A, Allen RA, Barone F. Phosphatidylinositol 3-kinase delta pathway: a novel therapeutic target for Sjögren's syndrome. Ann Rheum Dis 2018; 78:249-260. [PMID: 30472652 PMCID: PMC6352416 DOI: 10.1136/annrheumdis-2017-212619] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 09/28/2018] [Accepted: 10/18/2018] [Indexed: 01/08/2023]
Abstract
Background The phosphatidylinositol 3-kinase delta isoform (PI3Kδ) belongs to an intracellular lipid kinase family that regulate lymphocyte metabolism, survival, proliferation, apoptosis and migration and has been successfully targeted in B-cell malignancies. Primary Sjögren’s syndrome (pSS) is a chronic immune-mediated inflammatory disease characterised by exocrine gland lymphocytic infiltration and B-cell hyperactivation which results in systemic manifestations, autoantibody production and loss of glandular function. Given the central role of B cells in pSS pathogenesis, we investigated PI3Kδ pathway activation in pSS and the functional consequences of blocking PI3Kδ in a murine model of focal sialoadenitis that mimics some features of pSS. Methods and results Target validation assays showed significant expression of phosphorylated ribosomal protein S6 (pS6), a downstream mediator of the phosphatidylinositol 3-kinase delta (PI3Kδ) pathway, within pSS salivary glands. pS6 distribution was found to co-localise with T/B cell markers within pSS aggregates and the CD138+ plasma cells infiltrating the glands. In vivo blockade of PI3Kδ activity with seletalisib, a PI3Kδ-selective inhibitor, in a murine model of focal sialoadenitis decreased accumulation of lymphocytes and plasma cells within the glands of treated mice in the prophylactic and therapeutic regimes. Additionally, production of lymphoid chemokines and cytokines associated with ectopic lymphoneogenesis and, remarkably, saliva flow and autoantibody production, were significantly affected by treatment with seletalisib. Conclusion These data demonstrate activation of PI3Kδ pathway within the glands of patients with pSS and its contribution to disease pathogenesis in a model of disease, supporting the exploration of the therapeutic potential of PI3Kδ pathway inhibition in this condition.
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Affiliation(s)
- Saba Nayar
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Joana Campos
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Charlotte G Smith
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Valentina Iannizzotto
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - David H Gardner
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Serena Colafrancesco
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK.,Dipartimento di Medicina Interna e Specialita' Mediche, Sapienza, University of Rome, Rome, Italy
| | - Elena Pipi
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Florian Kollert
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK.,Rheumatology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.,Department of Rheumatology, Immunology and Allergology, University Hospital, University of Bern, Bern, Switzerland
| | - Kelly J Hunter
- Immunology, HBRC, University of Birmingham, Birmingham, UK
| | | | - Christopher Dominic Buckley
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Sandwell and West Birmingham NHS Foundation Trust & Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Simon J Bowman
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Roberta Priori
- Dipartimento di Medicina Interna e Specialita' Mediche, Sapienza, University of Rome, Rome, Italy
| | - Guido Valesini
- Dipartimento di Medicina Interna e Specialita' Mediche, Sapienza, University of Rome, Rome, Italy
| | | | | | - Benjamin A Fisher
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Sandwell and West Birmingham NHS Foundation Trust & Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | | | | | - Francesca Barone
- Centre for Translational Inflammation Research, Institute of Inflammation and Ageing, College of Medical & Dental Sciences, University of Birmingham, Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK .,Rheumatology Department, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
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Becerra E, De La Torre I, Leandro MJ, Cambridge G. B cell phenotypes in patients with rheumatoid arthritis relapsing after rituximab: expression of B cell-activating factor-binding receptors on B cell subsets. Clin Exp Immunol 2017; 190:372-383. [PMID: 28800164 DOI: 10.1111/cei.13024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2017] [Indexed: 01/14/2023] Open
Abstract
Serum levels of B cell-activating factor (BAFF) rise following rituximab (RTX) therapy in patients with rheumatoid arthritis (RA). Initiation of naive B cell return to the periphery and autoreactive B cell expansion leading to relapse after RTX may therefore be linked to interactions between BAFF and BAFF-binding receptors (BBR). Relationships between serum BAFF and BBR expression [(BAFFR, calcium signal modulating cyclophilic ligand interactor (TACI) and B cell maturation antigen (BCMA)] were determined on B cell subsets, defined using immunoglobulin (Ig)D/CD38. Twenty pre-RTX and 18 RA patients relapsing after B cell depletion were included. Results were analysed with respect to timing of relapse up to 7 months after peripheral B cell return (≥ 5 B cells/μl) and to serum BAFF levels. After B cell return, B cell populations from relapsing patients had significantly lower BAFFR+ expression compared to HC and pre-RTX patients. The percentage of BAFFR+ B cells increased with time after B cell return and was correlated inversely with serum BAFF levels. BAFFR expression remained reduced. The percentage of TACI+ memory B cells were lower in RA patients after RTX compared with healthy controls (HC). BCMA expression (% and expression) did not differ between patients and HC. Relapse following B cell return appeared largely independent of the percentage of BAFFR+ or percentage of BCMA+ B cells or serum BAFF levels. The lower percentage of TACI+ memory B cells may reduce inhibitory signalling for B cell differentiation. In patients relapsing at longer periods after B cell return, recovery of the B cell pool was more complete, suggesting that selection or expansion of autoreactive B cells may be needed to precipitate relapse.
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Affiliation(s)
- E Becerra
- Department of Rheumatology, University College London, London, UK
| | - I De La Torre
- Department of Rheumatology, University College London, London, UK
| | - M J Leandro
- Department of Rheumatology, University College London, London, UK
| | - G Cambridge
- Department of Rheumatology, University College London, London, UK
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11
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First line treatment of pemphigus vulgaris with a novel protocol in patients with contraindications to systemic corticosteroids and immunosuppressive agents: Preliminary retrospective study with a seven year follow-up. Int Immunopharmacol 2016; 34:25-31. [DOI: 10.1016/j.intimp.2016.02.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/12/2016] [Accepted: 02/15/2016] [Indexed: 11/15/2022]
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12
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Ahmed AR, Shetty S, Kaveri S, Spigelman ZS. Treatment of recalcitrant bullous pemphigoid (BP) with a novel protocol: A retrospective study with a 6-year follow-up. J Am Acad Dermatol 2016; 74:700-8.e3. [DOI: 10.1016/j.jaad.2015.11.030] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 11/09/2015] [Accepted: 11/15/2015] [Indexed: 10/22/2022]
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Morais SA, Vilas-Boas A, Isenberg DA. B-cell survival factors in autoimmune rheumatic disorders. Ther Adv Musculoskelet Dis 2015; 7:122-51. [PMID: 26288664 PMCID: PMC4530383 DOI: 10.1177/1759720x15586782] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Autoimmune rheumatic disorders have complex etiopathogenetic mechanisms in which B cells play a central role. The importance of factors stimulating B cells, notably the B-cell activating factor (BAFF) and A proliferation inducing ligand (APRIL) axis is now recognized. BAFF and APRIL are cytokines essential for B-cell proliferation and survival from the immature stages to the development of plasma cells. Their levels are increased in some subsets of patients with autoimmune disorders. Several recent biologic drugs have been developed to block this axis, namely belimumab [already licensed for systemic lupus erythematosus (SLE) treatment], tabalumab, atacicept and blisibimod. Many clinical trials to evaluate the safety and efficacy of these drugs in several autoimmune disorders are ongoing, or have been completed recently. This review updates the information on the use of biologic agents blocking BAFF/APRIL for patients with SLE, rheumatoid arthritis, Sjögren's syndrome and myositis.
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Affiliation(s)
- Sandra A Morais
- Internal Medicine Department, Hospital Pedro Hispano, Matosinhos, Portugal
| | - Andreia Vilas-Boas
- Internal Medicine Department, Hospital Pedro Hispano, Matosinhos, Portugal
| | - David A Isenberg
- Centre for Rheumatology, University College London, Room 424, 4th Floor Rayne Building, 5 University Street, London WC1E 6JF, UK
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Noort AR, Tak PP, Tas SW. Non-canonical NF-κB signaling in rheumatoid arthritis: Dr Jekyll and Mr Hyde? Arthritis Res Ther 2015; 17:15. [PMID: 25774937 PMCID: PMC4308835 DOI: 10.1186/s13075-015-0527-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The nuclear factor-κB (NF-κB) family of transcription factors is essential for the expression of pro-inflammatory cytokines, but can also induce regulatory pathways. NF-κB can be activated via two distinct pathways: the classical or canonical pathway, and the alternative or non-canonical pathway. It is well established that the canonical NF-κB pathway is essential both in acute inflammatory responses and in chronic inflammatory diseases, including rheumatoid arthritis (RA). Although less extensively studied, the non-canonical NF-κB pathway is not only central in lymphoid organ development and adaptive immune responses, but is also thought to play an important role in the pathogenesis of RA. Importantly, this pathway appears to have cell type-specific functions and, since many different cell types are involved in the pathogenesis of RA, it is difficult to predict the net overall contribution of the non-canonical NF-κB pathway to synovial inflammation. In this review, we describe the current understanding of non-canonical NF-κB signaling in various important cell types in the context of RA and consider the relevance to the pathogenesis of the disease. In addition, we discuss current drugs targeting this pathway, as well as future therapeutic prospects.
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Duraisingham SS, Buckland M, Dempster J, Lorenzo L, Grigoriadou S, Longhurst HJ. Primary vs. secondary antibody deficiency: clinical features and infection outcomes of immunoglobulin replacement. PLoS One 2014; 9:e100324. [PMID: 24971644 PMCID: PMC4074074 DOI: 10.1371/journal.pone.0100324] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 05/23/2014] [Indexed: 12/04/2022] Open
Abstract
Secondary antibody deficiency can occur as a result of haematological malignancies or certain medications, but not much is known about the clinical and immunological features of this group of patients as a whole. Here we describe a cohort of 167 patients with primary or secondary antibody deficiencies on immunoglobulin (Ig)-replacement treatment. The demographics, causes of immunodeficiency, diagnostic delay, clinical and laboratory features, and infection frequency were analysed retrospectively. Chemotherapy for B cell lymphoma and the use of Rituximab, corticosteroids or immunosuppressive medications were the most common causes of secondary antibody deficiency in this cohort. There was no difference in diagnostic delay or bronchiectasis between primary and secondary antibody deficiency patients, and both groups experienced disorders associated with immune dysregulation. Secondary antibody deficiency patients had similar baseline levels of serum IgG, but higher IgM and IgA, and a higher frequency of switched memory B cells than primary antibody deficiency patients. Serious and non-serious infections before and after Ig-replacement were also compared in both groups. Although secondary antibody deficiency patients had more serious infections before initiation of Ig-replacement, treatment resulted in a significant reduction of serious and non-serious infections in both primary and secondary antibody deficiency patients. Patients with secondary antibody deficiency experience similar delays in diagnosis as primary antibody deficiency patients and can also benefit from immunoglobulin-replacement treatment.
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Affiliation(s)
| | - Matthew Buckland
- Immunology Department, Barts Health NHS Trust, London, United Kingdom
| | - John Dempster
- Immunology Department, Barts Health NHS Trust, London, United Kingdom
| | - Lorena Lorenzo
- Immunology Department, Barts Health NHS Trust, London, United Kingdom
| | - Sofia Grigoriadou
- Immunology Department, Barts Health NHS Trust, London, United Kingdom
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The effect of B-cell depletion therapy on serological evidence of B-cell and plasmablast activation in patients with rheumatoid arthritis over multiple cycles of rituximab treatment. J Autoimmun 2014; 50:67-76. [DOI: 10.1016/j.jaut.2013.12.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 11/29/2013] [Accepted: 12/03/2013] [Indexed: 02/06/2023]
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Duraisingham SS, Buckland MS, Grigoriadou S, Longhurst HJ. Secondary antibody deficiency. Expert Rev Clin Immunol 2014; 10:583-91. [PMID: 24684706 DOI: 10.1586/1744666x.2014.902314] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Secondary antibody deficiencies are defined by a quantitative or qualitative decrease in antibodies that occur most commonly as a consequence of renal or gastrointestinal immunoglobulin loss, hematological malignancies and corticosteroid, immunosuppressive or anticonvulsant medications. Patients with hematological malignancies or requiring immunosuppressive medications are known to be at increased risk of infection, but few studies directly address this relationship in the context of antibody deficiency. Immunoglobulin replacement therapy has been shown to be effective in reducing infections in primary and some secondary antibody deficiencies. The commonly encountered causes of secondary antibody deficiencies and their association with infection-related morbidity and mortality are discussed. Recommendations are made for screening and clinical management of those at risk.
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Affiliation(s)
- Sai S Duraisingham
- Immunology Department, Royal London Hospital, Barts Health NHS Trust, London, UK
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Choi IY, Gerlag DM, Herenius MJ, Thurlings RM, Wijbrandts CA, Foell D, Vogl T, Roth J, Tak PP, Holzinger D. MRP8/14 serum levels as a strong predictor of response to biological treatments in patients with rheumatoid arthritis. Ann Rheum Dis 2013; 74:499-505. [DOI: 10.1136/annrheumdis-2013-203923] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Shetty S, Ahmed AR. Preliminary analysis of mortality associated with rituximab use in autoimmune diseases. Autoimmunity 2013; 46:487-96. [DOI: 10.3109/08916934.2013.838563] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Leandro MJ. B-cell subpopulations in humans and their differential susceptibility to depletion with anti-CD20 monoclonal antibodies. Arthritis Res Ther 2013; 15 Suppl 1:S3. [PMID: 23566754 PMCID: PMC3624669 DOI: 10.1186/ar3908] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In humans, different B-cell subpopulations can be distinguished in peripheral blood
and other tissues on the basis of differential expression of various surface markers.
These different subsets correspond to different stages of maturation, activation and
differentiation. B-cell depletion therapy based on rituximab, an anti-CD20 mAb, is
widely used in the treatment of various malignant and autoimmune diseases. Rituximab
induces a very significant depletion of B-cell subpopulations in the peripheral blood
usually for a period of 6 to 9 months after one cycle of therapy. Cells detected
circulating during depletion are mainly CD20 negative plasmablasts. Data on depletion
of CD20-expressing B cells in solid tissues are limited but show that depletion is
significant but not complete, with bone marrow and spleen being more easily depleted
than lymph nodes. Factors influencing depletion are thought to include not only the
total drug dose administered and distribution into various tissues, but also B-cell
intrinsic and microenvironment factors influencing recruitment of effector mechanisms
and antigen and effector modulation. Available studies show that the degree of
depletion varies between individuals, even if treated with the same dose, but that it
tends to be consistent in the same individual. This suggests that individual factors
are important in determining the final extent of depletion.
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Affiliation(s)
- Maria J Leandro
- Centre for Rheumatology and Bloomsbury Rheumatology Unit, Rayne Building, Room 416, University College London, 5 University Street, London WC1E 6JF, UK.
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Li J, Ju Y, Bouta EM, Xing L, Wood RW, Kuzin I, Bottaro A, Ritchlin CT, Schwarz EM. Efficacy of B cell depletion therapy for murine joint arthritis flare is associated with increased lymphatic flow. ACTA ACUST UNITED AC 2013; 65:130-8. [PMID: 23002006 DOI: 10.1002/art.37709] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 09/13/2012] [Indexed: 12/30/2022]
Abstract
OBJECTIVE B cell depletion therapy ameliorates rheumatoid arthritis by mechanisms that are incompletely understood. Arthritis flare in tumor necrosis factor (TNF)-transgenic mice is associated with efferent lymph node (LN) "collapse," triggered by B cell translocation into lymphatic spaces and decreased lymphatic drainage. The aim of this study was to examine whether the efficacy of B cell depletion therapy is associated with restoration of lymphatic drainage due to removal of obstructing nodal B cells. METHODS We used contrast-enhanced magnetic resonance imaging, indocyanine green near-infrared imaging, and intravital immunofluorescence imaging to longitudinally assess synovitis, lymphatic flow, and cell migration in lymphatic vessels in TNF-transgenic mice. We conducted tests to determine whether the efficacy of B cell depletion therapy is associated with restoration of lymphatic draining and cell egress from arthritic joints. RESULTS Unlike active lymphatics to normal and prearthritic knees, afferent lymphatic vessels to collapsed LNs in inflamed knees do not pulse. Intravital immunofluorescence imaging demonstrated that CD11b+ monocyte/macrophages in lymphatic vessels afferent to expanding LNs travel at high velocity (mean±SD 186±37 μm/second), while these cells are stationary in lymphatic vessels afferent to collapsed popliteal LNs. B cell depletion therapy for arthritis flares in TNF-transgenic mice significantly decreased knee synovium volume (by 50% from the baseline level) and significantly increased lymphatic clearance compared with placebo (P<0.05). This increased lymphatic drainage restored macrophage egress from inflamed joints without recovery of the lymphatic pulse. CONCLUSION These results support a novel mechanism in which B cell depletion therapy for joint arthritis flares lessens inflammation by increasing lymphatic drainage and subsequent migration of cells and cytokines from the synovial space.
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Affiliation(s)
- Jie Li
- University of Rochester School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York 14642, USA
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Abstract
Within the B-cell follicle of secondary lymphoid organs, germinal center (GC) reactions produce high affinity antibody-secreting plasma cells (PCs) and memory B-cells necessary for the host's defense against invading pathogens. This process of GC formation is reliant on the activation of antigen-specific B-cells by T-cells capable of recognizing epitopes of the same antigenic complex. The unique architecture of secondary lymphoid organs facilitates these initial GC events through the placement of large clonally-diverse B-cell follicles near equally diverse T-cell zones. Antigen-activated B-cells that receive proper differentiation signals at the T-cell border of the B-cell follicle initiate an early GC B-cell transcriptional profile and migrate to follicular dendritic cell (FDC) networks within the B-cell follicle to seed the GC reaction. Peripheral to FDCs, GC B-cells rapidly divide in dark zones of the GC, and undergo somatic hypermutation of their immunoglobulin (Ig) variable domain. Newly formed GC B-cell clones then migrate into the GC light zone where they compete for antigen and secondary signals presented by FDCs and a specialized subset of CD4(+) T-cells known as T-follicular helper (T(FH)) cells. Survival, proliferative and differentiation signals delivered by mature FDCs and T(FH) cells initiate transcriptional programs that determine if GC B-cells become memory B-cells or terminally differentiated PCs. To prevent oncogenic transformation and/or the escape of autoreactive clones, there are several regulatory mechanisms that restrict GC B-cell proliferation and survival. Here we will detail the recent advances in GC B-cell biology that relate to their generation and fate-determination as well as their pathogenic potential.
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Affiliation(s)
- Keith M Hamel
- Department of Medicine, Section of Rheumatology and Gwen Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois 60637, USA.
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