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Messina OD, Vidal M, Adami G, Vidal LF, Clark P, Torres JAM, Lems W, Zerbini C, Arguissain C, Reginster JY, Lane NE. Chronic arthritides and bone structure: focus on rheumatoid arthritis-an update. Aging Clin Exp Res 2023:10.1007/s40520-023-02432-9. [PMID: 37222927 DOI: 10.1007/s40520-023-02432-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 05/01/2023] [Indexed: 05/25/2023]
Abstract
Normal bone remodeling depends of a balance between bone forming cells, osteoblasts and bone resorbing cells, the osteoclasts. In chronic arthritides and some inflammatory and autoimmune diseases such as rheumatoid arthritis, there is a great constellation of cytokines produced by pannus that impair bone formation and stimulate bone resorption by inducing osteoclast differentiation and inhibiting osteoblast maturation. Patients with chronic inflammation have multiple causes that lead to low bone mineral density, osteoporosis and a high risk of fracture including circulating cytokines, impaired mobility, chronic administration of glucocorticoids, low vitamin D levels and post-menopausal status in women, among others. Biologic agents and other therapeutic measures to reach prompt remission might ameliorate these deleterious effects. In many cases, bone acting agents need to be added to conventional treatment to reduce the risk of fractures and to preserve articular integrity and independency for daily living activities. A limited number of studies related to fractures in chronic arthritides were published, and future investigation is needed to determine the risk of fractures and the protective effects of different treatments to reduce this risk.
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Affiliation(s)
- Osvaldo Daniel Messina
- Collaborating Centre WHO, Investigaciones Reumatológicas y Osteológicas (IRO), Buenos Aires, Argentina
- International Osteoporosis Foundation (IOF), Buenos Aires, Argentina
| | - Maritza Vidal
- Centro de Diagnóstico de Osteoporosis y Enfermedades Reumáticas (CEDOR), Lima, Peru.
| | - Giovanni Adami
- Rheumatology Section, Department of Medicine, University of Verona, Verona, Italy
| | - Luis Fernando Vidal
- Centro de Diagnóstico de Osteoporosis y Enfermedades Reumáticas (CEDOR), Lima, Peru
- Regional Advisory Council for Latin America - International Osteoporosis Foundation (IOF), Lima, Peru
| | - Patricia Clark
- International Osteoporosis Foundation (IOF), Buenos Aires, Argentina
- Chief of Clinical Epidemiology Unit-Hospital Federico Gomez School of Medicine UNAM, Mexico City, Mexico
| | | | - William Lems
- Department of Rheumatology, Amsterdam UMC, Location VU University Medical Centre Amsterdam, Amsterdam, North-Holland, The Netherlands
| | | | - Constanza Arguissain
- Collaborating Centre WHO, Investigaciones Reumatológicas y Osteológicas (IRO), Buenos Aires, Argentina
| | - Jean-Yves Reginster
- Division of Public Health, Epidemiology and Health Economics, WHO Collaborating Centre for Public Health, Aspects of Musculoskeletal Health and Ageing, University of Liege, Liege, Belgium
| | - Nancy E Lane
- Center for Musculoskeletal Health, University of California at Davis School of Medicine, Sacramento, CA, 95817, USA
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Hasegawa T, Ishii M. Pathological Osteoclasts and Precursor Macrophages in Inflammatory Arthritis. Front Immunol 2022; 13:867368. [PMID: 35464401 PMCID: PMC9024112 DOI: 10.3389/fimmu.2022.867368] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/18/2022] [Indexed: 01/10/2023] Open
Abstract
Macrophages comprise a variety of subsets with diverse biological functions, including inflammation, tissue repair, regeneration, and fibrosis. In the bone marrow, macrophages differentiate into multinucleated osteoclasts, which have a unique bone-destroying capacity and play key roles in physiological bone remodelling. In contrast, osteoclasts are also involved in inflammatory bone erosion in arthritis and it has been unclear whether the osteoclasts in different tissue settings arise from similar monocytoid precursors and share similar phenotypes. Rapid progresses in the sequencing technologies have provided many important insights regarding the heterogeneity of different types of osteoclasts. The application of single-cell RNA sequencing (scRNA-seq) to the osteoclast precursor-containing macrophages enabled to identify the specific subpopulation differentiating into pathological mature osteoclasts in joints. Furthermore, an intravital imaging technology using two-photon microscopy has succeeded in visualizing the real-time dynamics of immune cells in the synovial microenvironment. These technologies together contributed to characterize the unique macrophages in the inflamed synovium, termed “arthritis-associated osteoclastogenic macrophages (AtoMs)”, causing the pathological bone destruction in inflammatory arthritis. Here, we review and discuss how novel technologies help to better understand the role of macrophages in inflammatory arthritis, especially focusing of osteoclastogenesis at the pannus-bone interface.
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Affiliation(s)
- Tetsuo Hasegawa
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Osaka, Japan
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Masaru Ishii
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Osaka, Japan
- World Premier International Research Center Initiative (WPI)-Immunology Frontier Research Center, Osaka University, Osaka, Japan
- Laboratory of Bioimaging and Drug Discovery, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
- *Correspondence: Masaru Ishii,
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Hu Q, Zhong X, Tian H, Liao P. The Efficacy of Denosumab in Patients With Rheumatoid Arthritis: A Systematic Review and Pooled Analysis of Randomized or Matched Data. Front Immunol 2022; 12:799575. [PMID: 35069583 PMCID: PMC8766643 DOI: 10.3389/fimmu.2021.799575] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 12/13/2021] [Indexed: 12/19/2022] Open
Abstract
Objective The purpose of this study was to evaluate the efficacy of denosumab treatment in patients with rheumatoid arthritis (RA). Methods The Medline, Embase and Cochrane Library databases were searched for relevant clinical studies. Studies that assessed the efficacy of denosumab in patients with RA were identified. The primary endpoints were the percent changes in bone mineral density (BMD), and the changes in modified total Sharp score (mTSS), modified Sharp erosion score and joint space narrowing (JSN) score. Pooled analyses were calculated using random-effect models. Results After searching the literature and performing further detailed assessments, 10 studies with a total of 1758 patients were included in the quantitative analysis. Pooled analyses showed that denosumab treatment significantly increased the percent changes in lumbar spine BMD [mean difference (MD): 5.12, confidence intervals (CI): 4.15 to 6.09], total hip BMD (MD: 2.72, 95% CI: 1.80 to 3.64) and femoral neck BMD (MD: 2.20, 95% CI: 0.94 to 3.46) compared with controls. Moreover, denosumab treatment significantly decreased the changes in mTSS (MD: -0.63, 95% CI: -0.86 to -0.41) and modified Sharp erosion score (MD: -0.62, 95% CI: -0.88 to -0.35). Subgroup analysis indicated that denosumab was superior to bisphosphonates for the improvement of BMD and the mitigation of joint destruction. Conclusion Denosumab treatment was associated with increased BMD and alleviated progression of joint destruction in RA patients, even when compared with bisphosphonates.
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Affiliation(s)
- Qiongwen Hu
- Department of Medical Laboratory, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Xue Zhong
- Department of Nephrology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Hua Tian
- Department of Medical Laboratory, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
| | - Pu Liao
- Department of Medical Laboratory, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, China
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Hasegawa T, Kikuta J, Ishii M. Imaging of bone and joints in vivo: pathological osteoclastogenesis in arthritis. Int Immunol 2021; 33:679-686. [PMID: 34324641 DOI: 10.1093/intimm/dxab047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 07/28/2021] [Indexed: 11/12/2022] Open
Abstract
Osteoimmunology highlights the reciprocal interactions between the skeletal and immune systems. Over the past two decades, many molecules that link the two have been identified, including cytokines, receptors and transcription factors, leading to successful translation of research into therapeutic approaches to autoimmune diseases such as rheumatoid arthritis. The development of an intravital imaging system using multi-photon microscopy, combined with a variety of fluorescent probes and reporter mouse strains, has provided valuable insights into the real-time dynamics of osteoclasts and immune cells in the bone marrow. This technique is now applied to the synovial tissue of arthritic mice to investigate the pathogenesis of osteoimmune diseases and enables direct observation of complex biological phenomena in vivo. In addition, rapid progress in the next-generation sequencing technologies has provided important insights into the field of osteoimmunology through characterizing individual cells in the synovial microenvironment. Single-cell RNA sequencing (scRNA-seq) dissects cellular heterogeneity within a biological system and enables the identification of specific cells differentiating into mature osteoclasts within the previously defined "osteoclast precursor (OP)-containing population". In this review, we will explain the cellular interactions and cytokine milieu involved in inflammatory bone destruction and update how the novel technologies, such as scRNA-seq and intravital imaging, have contributed to better understand the pathogenesis of bone destruction in arthritis.
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Affiliation(s)
- Tetsuo Hasegawa
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Yamada-oka, Suita, Osaka, Japan
| | - Junichi Kikuta
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Yamada-oka, Suita, Osaka, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Yamada-oka, Suita, Osaka, Japan.,Laboratory of Bioimaging and Drug Discovery, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
| | - Masaru Ishii
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Yamada-oka, Suita, Osaka, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Yamada-oka, Suita, Osaka, Japan.,Laboratory of Bioimaging and Drug Discovery, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
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Raterman HG, Bultink IE, Lems WF. Osteoporosis in patients with rheumatoid arthritis: an update in epidemiology, pathogenesis, and fracture prevention. Expert Opin Pharmacother 2020; 21:1725-1737. [PMID: 32605401 DOI: 10.1080/14656566.2020.1787381] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Rheumatoid arthritis (RA) is a chronic disabling disease characterized by a symmetrical articular involvement due to ongoing joint inflammation, if left insufficiently treated. Local and generalized bone loss is one of the main extra-articular complications of RA and leads to an increased risk for fragility fractures, which further impair functional ability, quality of life, and life expectancy. Therefore, there is an urgent need for good fracture risk management in the vulnerable RA patient. AREAS COVERED The authors review: the epidemiology and pathophysiology (i.e. risk factors) of osteoporosis (OP), fracture, and vertebral fracture risk assessment, the effects of anti-rheumatic drugs on bone loss, pharmacological treatment of OP in RA including both bisphosphonates (BP) and newer drugs including anti-resorptives and osteoanabolic treatment options. EXPERT OPINION Patients with active RA have elevated bone resorption and local bone loss. Moreover, these patients are at increased risk for generalized bone loss, vertebral and non-vertebral fractures. Since general risk factors (such as low BMI, fall risk) and RA-related factors play a role, optimal fracture prevention in RA patients is based on optimal diagnostics based on both of these factors, and on the use of adequate non-medical and medical treatment options.
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Affiliation(s)
- Hennie G Raterman
- Department of Rheumatology, North West Clinics , Alkmaar, The Netherlands
| | - Irene Em Bultink
- Department of Rheumatology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Rheumatology and Immunology Center , Amsterdam, The Netherlands
| | - Willem F Lems
- Department of Rheumatology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Rheumatology and Immunology Center , Amsterdam, The Netherlands.,Department of Rheumatology, Amsterdam Rheumatology and Immunology Center , Amsterdam, The Netherlands
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Pharmacological Management of Osteoporosis in Rheumatoid Arthritis Patients: A Review of the Literature and Practical Guide. Drugs Aging 2020; 36:1061-1072. [PMID: 31541358 PMCID: PMC6884430 DOI: 10.1007/s40266-019-00714-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Rheumatoid arthritis (RA) is a chronic disabling disease that is associated with increased localized and generalized osteoporosis (OP). Previous studies estimated that approximately one-third of the RA population experience bone loss. Moreover, RA patients suffer from a doubled fracture incidence depending on several clinical factors, such as disease severity, age, glucocorticoid (GC) use, and immobility. As OP fractures are related to impaired quality of life and increased mortality rates, OP has an enormous impact on global health status. Therefore, there is an urgent need for a holistic approach in daily clinical practice. In other words, both OP- and RA-related factors should be taken into account in treatment guidelines for OP in RA. First, to determine the actual fracture risk, dual-energy X-ray absorptiometry (DXA), including vertebral fracture assessment (VFA) and calculation of the 10-year fracture risk with FRAX®, should be performed. In case of high fracture risk, calcium and vitamin D should be supplemented alongside anti-osteoporotic treatment. Importantly, RA treatment should be optimal, aiming at low disease activity or remission. Moreover, GC treatment should be at the lowest possible dose. In this way, good fracture risk management will lead to fracture risk reduction in RA patients. This review provides a practical guide for clinicians regarding pharmacological treatment options in RA patients with OP, taking into account both osteoporotic-related factors and factors related to RA.
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HASEGAWA T, ISHII M. Visualizing bone tissue in homeostatic and pathological conditions. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2020; 96:43-49. [PMID: 32037368 PMCID: PMC7030973 DOI: 10.2183/pjab.96.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 11/18/2019] [Indexed: 05/25/2023]
Abstract
The human body is comprised of hundreds of bones, which are constantly regenerated through the interactions of two cell types: osteoblasts and osteoclasts. Given the difficulty of analyzing their intravital dynamics, we have developed a system for intravital imaging of the bone marrow cavity using two-photon microscopy, to visualize the dynamic behaviors of living bone cells without sectioning. Combined with the newly developed chemical fluorescent probes to detect localized acidification caused by osteoclasts, we identified two distinct functional states of mature osteoclasts, i.e., "bone-resorptive" and "non-resorptive". Here, we focus on the dynamics and functions of bone cells within the bone marrow cavity and discuss how this novel approach has been applied to evaluate the mechanisms of action of drugs currently in clinical use. We further introduce our recent study that identified arthritis-associated osteoclastogenic macrophages in inflamed synovium and revealed their differentiation trajectory into the pathological osteoclasts, which together represent to a new paradigm in bone research.
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Affiliation(s)
- Tetsuo HASEGAWA
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Suita, Osaka, Japan
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Masaru ISHII
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Suita, Osaka, Japan
- WPI-Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan
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8
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Hasegawa T, Kikuta J, Ishii M. Imaging the Bone-Immune Cell Interaction in Bone Destruction. Front Immunol 2019; 10:596. [PMID: 30972080 PMCID: PMC6443987 DOI: 10.3389/fimmu.2019.00596] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/05/2019] [Indexed: 11/13/2022] Open
Abstract
Bone is a highly dynamic organ that is continuously being remodeled by the reciprocal interactions between bone and immune cells. We have originally established an advanced imaging system for visualizing the in vivo behavior of osteoclasts and their precursors in the bone marrow cavity using two-photon microscopy. Using this system, we found that the blood-enriched lipid mediator, sphingosine-1-phosphate, controlled the migratory behavior of osteoclast precursors. We also developed pH-sensing chemical fluorescent probes to detect localized acidification by bone-resorbing osteoclasts on the bone surface in vivo, and identified two distinct functional states of differentiated osteoclasts, "bone-resorptive" and "non-resorptive." Here, we summarize our studies on the dynamics and functions of bone and immune cells within the bone marrow. We further discuss how our intravital imaging techniques can be applied to evaluate the mechanisms of action of biological agents in inflammatory bone destruction. Our intravital imaging techniques would be beneficial for studying the cellular dynamics in arthritic inflammation and bone destruction in vivo and would also be useful for evaluating novel therapies in animal models of bone-destroying diseases.
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Affiliation(s)
- Tetsuo Hasegawa
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Osaka, Japan.,Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Junichi Kikuta
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Osaka, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Masaru Ishii
- Department of Immunology and Cell Biology, Graduate School of Medicine and Frontier Biosciences, Osaka University, Osaka, Japan.,WPI-Immunology Frontier Research Center, Osaka University, Osaka, Japan
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Colangelo L, Biamonte F, Pepe J, Cipriani C, Minisola S. Understanding and managing secondary osteoporosis. Expert Rev Endocrinol Metab 2019; 14:111-122. [PMID: 30735441 DOI: 10.1080/17446651.2019.1575727] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/22/2019] [Indexed: 02/08/2023]
Abstract
INTRODUCTION The term secondary osteoporosis (SO) identifies a reduction of bone mass related to a well-established disease or pharmacological agent. The identification of the underlying disease often represents a challenging situation in clinical practice. AREAS COVERED The prevalence of SO in the real world may vary, ranging from 17% to 80%; therefore, search for a form of SO represents a pillar when evaluating patients with osteoporosis. Guidelines for treatment of specific secondary forms of osteoporosis, such as glucocorticoid-induced osteoporosis, have been published even though often neglected in clinical practice. For the majority of SO, there are currently no specific guidelines concerning treatment with only few trials showing the effect of bone-active drugs on fracture risk reduction. EXPERT OPINION Healthcare professionals should be aware of the secondary forms of osteoporosis, in particular when the reason for reduced skeletal resistance is uncertain or when bone mineral density results are unsatisfactory in a patient compliant to therapy. In a few cases (such as, for example: no response to therapy, better classification of bone involvement in patients with kidney failure, suspicion of rare metabolic bone disease) bone biopsy is needed to investigate the patient. This review highlights recent advances in understanding and managing SO.
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Affiliation(s)
- Luciano Colangelo
- a Department of Internal Medicine and Medical Disciplines , "Sapienza" University of Rome , Rome , Italy
| | - Federica Biamonte
- a Department of Internal Medicine and Medical Disciplines , "Sapienza" University of Rome , Rome , Italy
| | - Jessica Pepe
- a Department of Internal Medicine and Medical Disciplines , "Sapienza" University of Rome , Rome , Italy
| | - Cristiana Cipriani
- a Department of Internal Medicine and Medical Disciplines , "Sapienza" University of Rome , Rome , Italy
| | - Salvatore Minisola
- a Department of Internal Medicine and Medical Disciplines , "Sapienza" University of Rome , Rome , Italy
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Mechanisms and therapeutic targets for bone damage in rheumatoid arthritis, in particular the RANK-RANKL system. Curr Opin Pharmacol 2018; 40:110-119. [DOI: 10.1016/j.coph.2018.03.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/20/2018] [Indexed: 01/01/2023]
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11
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Park JH, Park SH, Lee HY, Lee JW, Lee BK, Lee BY, Kim JH, Kim MS. An injectable, electrostatically interacting drug depot for the treatment of rheumatoid arthritis. Biomaterials 2018; 154:86-98. [DOI: 10.1016/j.biomaterials.2017.10.055] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 10/26/2017] [Accepted: 10/26/2017] [Indexed: 12/17/2022]
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12
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Walsh MC, Takegahara N, Kim H, Choi Y. Updating osteoimmunology: regulation of bone cells by innate and adaptive immunity. Nat Rev Rheumatol 2018; 14:146-156. [PMID: 29323344 DOI: 10.1038/nrrheum.2017.213] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Osteoimmunology encompasses all aspects of the cross-regulation of bone and the immune system, including various cell types, signalling pathways, cytokines and chemokines, under both homeostatic and pathogenic conditions. A number of key areas are of increasing interest and relevance to osteoimmunology researchers. Although rheumatoid arthritis has long been recognized as one of the most common autoimmune diseases to affect bone integrity, researchers have focused increased attention on understanding how molecular triggers and innate signalling pathways (such as Toll-like receptors and purinergic signalling pathways) related to pathogenic and/or commensal microbiota are relevant to bone biology and rheumatic diseases. Additionally, although most discussions relating to osteoimmune regulation of homeostasis and disease have focused on the effects of adaptive immune responses on bone, evidence exists of the regulation of immune cells by bone cells, a concept that is consistent with the established role of the bone marrow in the development and homeostasis of the immune system. The active regulation of immune cells by bone cells is an interesting emerging component of investigations that seek to understand how to control immune-associated diseases of the bone and joints.
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Affiliation(s)
- Matthew C Walsh
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Noriko Takegahara
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Hyunsoo Kim
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
| | - Yongwon Choi
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA
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