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Zhang T, Wang F, Xu L, Yang YG. Structural-functional diversity of CD47 proteoforms. Front Immunol 2024; 15:1329562. [PMID: 38426113 PMCID: PMC10902115 DOI: 10.3389/fimmu.2024.1329562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 02/01/2024] [Indexed: 03/02/2024] Open
Abstract
The ubiquitously expressed transmembrane glycoprotein CD47 participates in various important physiological cell functions, including phagocytosis, apoptosis, proliferation, adhesion, and migration, through interactions with its ligands, including the inhibitory receptor signal regulatory protein α (SIRPα), secreted glycoprotein thrombospondin-1 (TSP-1), and integrins. Elevated expression of CD47 is observed in a wide range of cancer cells as a mechanism for evading the immune system, blocking the interaction between the CD47 and SIRPα is the most advanced and promising therapeutic approach currently investigated in multiple clinical trials. The widely held view that a single type of CD47 protein acts through membrane interactions has been challenged by the discovery of a large cohort of CD47 proteins with cell-, tissue-, and temporal-specific expression and functional profiles. These profiles have been derived from a single gene through alternative splicing and post-translational modifications, such as glycosylation, pyroglutamate modification, glycosaminoglycan modification, and proteolytic cleavage and, to some extent, via specific CD47 clustering in aging and tumor cells and the regulation of its subcellular localization by a pre-translational modification, alternative cleavage and polyadenylation (APA). This review explores the origins and molecular properties of CD47 proteoforms and their roles under physiological and pathological conditions, mentioning the new methods to improve the response to the therapeutic inhibition of CD47-SIRPα immune checkpoints, contributing to the understanding of CD47 proteoform diversity and identification of novel clinical targets and immune-related therapeutic candidates.
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Affiliation(s)
- Ting Zhang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, Institute of Immunology, The First Hospital of Jilin University, Changchun, Jilin, China
- National-Local Joint Engineering Laboratory of Animal Models for Human Disease, The First Hospital of Jilin University, Changchun, China
| | - Feng Wang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, Institute of Immunology, The First Hospital of Jilin University, Changchun, Jilin, China
- National-Local Joint Engineering Laboratory of Animal Models for Human Disease, The First Hospital of Jilin University, Changchun, China
| | - Lu Xu
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, Institute of Immunology, The First Hospital of Jilin University, Changchun, Jilin, China
- National-Local Joint Engineering Laboratory of Animal Models for Human Disease, The First Hospital of Jilin University, Changchun, China
| | - Yong-Guang Yang
- Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, Institute of Immunology, The First Hospital of Jilin University, Changchun, Jilin, China
- National-Local Joint Engineering Laboratory of Animal Models for Human Disease, The First Hospital of Jilin University, Changchun, China
- International Center of Future Science, Jilin University, Changchun, Jilin, China
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2
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Hao Y, Zhou X, Li Y, Li B, Cheng L. The CD47-SIRPα axis is a promising target for cancer immunotherapies. Int Immunopharmacol 2023; 120:110255. [PMID: 37187126 DOI: 10.1016/j.intimp.2023.110255] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/22/2023] [Accepted: 04/27/2023] [Indexed: 05/17/2023]
Abstract
Cluster of differentiation 47(CD47) is a transmembrane protein that is ubiquitously found on the surface of many cells in the body and uniquely overexpressed by both solid and hematologic malignant cells. CD47 interacts with signal-regulatory protein α (SIRPα), to trigger a "don't eat me" signal and thereby achieve cancer immune escape by inhibiting macrophage-mediated phagocytosis. Thus, blocking the CD47-SIRPα phagocytosis checkpoint, for release of the innate immune system, is a current research focus. Indeed, targeting the CD47-SIRPα axis as a cancer immunotherapy has shown promising efficacies in pre-clinical outcomes. Here, we first reviewed the origin, structure, and function of the CD47-SIRPα axis. Then, we reviewed its role as a target for cancer immunotherapies, as well as the factors regulating CD47-SIRPα axis-based immunotherapies. We specifically focused on the mechanism and progress of CD47-SIRPα axis-based immunotherapies and their combination with other treatment strategies. Finally, we discussed the challenges and directions for future research and identified potential CD47-SIRPα axis-based therapies that are suitable for clinical application.
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Affiliation(s)
- Yu Hao
- State Key Laboratory of Oral Diseases & West China Hospital of Stomatology & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610041, China; Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, China
| | - Xinxuan Zhou
- State Key Laboratory of Oral Diseases & West China Hospital of Stomatology & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610041, China
| | - Yiling Li
- State Key Laboratory of Oral Diseases & West China Hospital of Stomatology & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610041, China; Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, China
| | - Bolei Li
- State Key Laboratory of Oral Diseases & West China Hospital of Stomatology & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610041, China; Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, China.
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & West China Hospital of Stomatology & National Clinical Research Center for Oral Diseases, Sichuan University, Chengdu 610041, China; Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, China.
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3
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Jalil AR, Tobin MP, Discher DE. Suppressing or Enhancing Macrophage Engulfment through the Use of CD47 and Related Peptides. Bioconjug Chem 2022; 33:1989-1995. [PMID: 35316023 PMCID: PMC9990087 DOI: 10.1021/acs.bioconjchem.2c00019] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Foreign particles and microbes are rapidly cleared by macrophages in vivo, although many key aspects of uptake mechanisms remain unclear. "Self" cells express CD47 which functions as an anti-phagocytic ligand for SIRPα on macrophages, particularly when pro-phagocytic ligands such as antibodies are displayed in parallel. Here, we review CD47 and related "Self" peptides as modulators of macrophage uptake. Nanoparticles conjugated with either CD47 or peptides derived from its SIRPα binding site can suppress phagocytic uptake by macrophages in vitro and in vivo, with similar findings for CD47-displaying viruses. Drugs, dyes, and genes as payloads thus show increased delivery to targeted cells. On the other hand, CD47 expression by cancer cells enables such cells to evade macrophages and immune surveillance. This has motivated development of soluble antagonists to CD47-SIRPα, ranging from blocking antibodies in the clinic to synthetic peptides in preclinical models. CD47 and peptides are thus emerging as dual-use phagocytosis modulators against diseases.
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4
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Altin JG, Zhao Y. Using peptides to promote delivery and improve anti-tumour efficacy of liposomal drug. J Drug Target 2021; 30:544-556. [PMID: 34939907 DOI: 10.1080/1061186x.2021.2020799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Liposomal drugs exhibit advantages for cancer therapy, but efficacy is often limited by their rapid clearance from blood by the reticuloendothelial system, and an inability to target and penetrate tumours. Interestingly, a 21-amino acid SIRP-α- (signal regulatory protein-α) interacting 'self' peptide is reported to inhibit uptake by phagocytes. Also, 'iRGD' a 9-amino acid cyclic peptide that binds αvβ3 integrins and neuropilin-1 (NRP-1), promotes targeting and penetration of drug into tumours. Here we explore the potential of nitrilotriacetic acid-ditetra-decylamine (NTA3-DTDA)-containing liposomes (NTA-liposomes) engrafted with His-tagged forms of 'self' peptide (pCD47) to prolong circulation time in blood after iv administration, and of iRGD peptide (piRGD) to enhance treatment efficacy of doxorubicin-containing liposomes (Caelyx). Our results show that pre-incubation of murine phagocytic DC2.4 and RAW246.7 cells with pCD47 inhibits uptake of NTA-liposomes in vitro, but engraftment of pCD47 surprisingly reduces liposome lifetime in blood. Engraftment of piRGD promoted binding of NTA-liposomes to murine B16 melanoma and CT26 colorectal carcinoma cells in vitro. Importantly, iv administration of piRGD-engrafted Caelyx was found to significantly inhibit tumour growth and prolong survival in both B16 and CT26 murine tumour models. Our results show that engraftment of piRGD onto Caelyx is a convenient strategy to enhance treatment efficacy.
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Affiliation(s)
- Joseph G Altin
- Division of Biomedical Science and Biochemistry, Research School of Biology, ANU College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, 2601, Australia
| | - Yabing Zhao
- Division of Biomedical Science and Biochemistry, Research School of Biology, ANU College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, 2601, Australia
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5
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Advances in culture methods for acute myeloid leukemia research. Oncoscience 2021; 8:82-90. [PMID: 34368398 PMCID: PMC8336936 DOI: 10.18632/oncoscience.540] [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: 04/09/2021] [Accepted: 07/28/2021] [Indexed: 12/18/2022] Open
Abstract
Conventional suspension cultures have been used in Acute Myeloid Leukemia (AML) research to study its biology as well as to screen any drug molecules, since its inception. Co-culture models of AML cells and other stromal cells as well as 3 dimensional (3D) culture models have gained much attention recently. These culture models try to recapitulate the tumour microenvironment and are found to be more suitable than suspension cultures. Though animal models are being used, they require more time, effort and facilities and hence, it is essential to develop cell culture models for high-throughput screening of drugs. Here, we discuss a new co-culture model developed by our research group involving acute myeloid leukemia (AML) cells and stimulated macrophages. Other studies on co-culture systems and relevance of 3D culture in leukemic research in understanding the pathology and treatment of leukemia are also reviewed.
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6
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Niu D, Ma X, Yuan T, Niu Y, Xu Y, Sun Z, Ping Y, Li W, Zhang J, Wang T, Church GM. Porcine genome engineering for xenotransplantation. Adv Drug Deliv Rev 2021; 168:229-245. [PMID: 32275950 DOI: 10.1016/j.addr.2020.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/28/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
The extreme shortage of human donor organs for treatment of patients with end-stage organ failures is well known. Xenotransplantation, which might provide unlimited organ supply, is a most promising strategy to solve this problem. Domestic pigs are regarded as ideal organ-source animals owing to similarity in anatomy, physiology and organ size to humans as well as high reproductive capacity and low maintenance cost. However, several barriers, which include immune rejection, inflammation and coagulative dysfunctions, as well as the cross-species transmission risk of porcine endogenous retrovirus, blocked the pig-to-human xenotransplantation. With the rapid development of genome engineering technologies and the potent immunosuppressive medications in recent years, these barriers could be eliminated through genetic modification of pig genome together with the administration of effective immunosuppressants. A number of candidate genes involved in the regulation of immune response, inflammation and coagulation have been explored to optimize porcine xenograft survival in non-human primate recipients. PERV inactivation in pigs has also been accomplished to firmly address the safety issue in pig-to-human xenotransplantation. Many encouraging preclinical milestones have been achieved with some organs surviving for years. Therefore, the clinical trials of some promising organs, such as islet, kidney and heart, are aimed to be launched in the near future.
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Affiliation(s)
- Dong Niu
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Xiang Ma
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, College of Animal Science and Technology & College of Veterinary Medicine of Zhejiang A&F University, Hangzhou, P.R. China
| | - Taoyan Yuan
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, China
| | - Yifan Niu
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China
| | - Yibin Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zhongxin Sun
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China
| | - Yuan Ping
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Weifen Li
- College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jufang Zhang
- Cosmetic & Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, Zhejiang 310006, China.
| | - Tao Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, Jiangsu 211300, China.
| | - George M Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
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7
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Yu WB, Ye ZH, Chen X, Shi JJ, Lu JJ. The development of small-molecule inhibitors targeting CD47. Drug Discov Today 2020; 26:561-568. [PMID: 33197622 DOI: 10.1016/j.drudis.2020.11.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 10/12/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022]
Abstract
Immunotherapy has become an indispensable part of cancer treatment. A pivotal phagocytosis checkpoint, named cluster of differentiation 47 (CD47), which functions as 'don't eat me' signal to protect cells from phagocytosis upon interaction with signal regulatory protein alpha (SIRPα) on macrophages, has recently attracted much attention. Numerous antibodies targeting the CD47/SIRPα axis have shown encouraging efficacy in clinical trials. Meanwhile, studies on small-molecule inhibitors that interfere with CD47/SIRPα interaction or regulate CD47 expression are also in full swing. In this review, we summarize the small-molecule inhibitors interrupting the binding of CD47/SIRPα and regulating CD47 at the transcriptional, translational, and post-translational modification (PTM) levels. We provide perspectives and strategies for targeting the CD47/SIRPα phagocytosis checkpoint.
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Affiliation(s)
- Wei-Bang Yu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Zi-Han Ye
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Xiuping Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Jia-Jie Shi
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
| | - Jin-Jian Lu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
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8
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Feng R, Zhao H, Xu J, Shen C. CD47: the next checkpoint target for cancer immunotherapy. Crit Rev Oncol Hematol 2020; 152:103014. [PMID: 32535479 DOI: 10.1016/j.critrevonc.2020.103014] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 05/22/2020] [Accepted: 05/28/2020] [Indexed: 02/05/2023] Open
Abstract
Cancer immunotherapy using checkpoint blockade has brought about a paradigm shift in the treatment of advanced-stage cancers. Unfortunately, not all patients benefit from these therapies, paving the way for other immune checkpoints to be targeted. CD47, a 'marker-of-self' protein that is overexpressed broadly across tumor types, is emerging as a novel potent macrophage immune checkpoint for cancer immunotherapy. Recently, CD47 blockade by Hu5F9-G4 has shown promise combined with Rituximab in non-Hodgkin's lymphoma. Here we review the complex structure and various physiological functions of CD47 and their implications in cancer biology. Further, this review considers future directions and challenges in advancing this promising target platform to widespread therapeutic use.
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Affiliation(s)
- Ridong Feng
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Hai Zhao
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Jianguo Xu
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
| | - Chongyang Shen
- Basic Medicine School, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, China; Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui 230038, China.
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9
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Jalil AR, Andrechak JC, Discher DE. Macrophage checkpoint blockade: results from initial clinical trials, binding analyses, and CD47-SIRPα structure-function. Antib Ther 2020; 3:80-94. [PMID: 32421049 PMCID: PMC7206415 DOI: 10.1093/abt/tbaa006] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/07/2020] [Accepted: 04/14/2020] [Indexed: 12/11/2022] Open
Abstract
The macrophage checkpoint is an anti-phagocytic interaction between signal regulatory protein alpha (SIRPα) on a macrophage and CD47 on all types of cells - ranging from blood cells to cancer cells. This interaction has emerged over the last decade as a potential co-target in cancer when combined with other anti-cancer agents, with antibodies against CD47 and SIRPα currently in preclinical and clinical development for a variety of hematological and solid malignancies. Monotherapy with CD47 blockade is ineffective in human clinical trials against many tumor types tested to date, except for rare cutaneous and peripheral lymphomas. In contrast, pre-clinical results show efficacy in multiple syngeneic mouse models of cancer, suggesting that many of these tumor models are more immunogenic and likely artificial compared to human tumors. However, combination therapies in humans of anti-CD47 with agents such as the anti-tumor antibody rituximab do show efficacy against liquid tumors (lymphoma) and are promising. Here, we review such trials as well as key interaction and structural features of CD47-SIRPα.
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Affiliation(s)
- AbdelAziz R Jalil
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, USA
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, PA, USA
| | - Jason C Andrechak
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, PA, USA
- Graduate Group in Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Dennis E Discher
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, PA, USA
- Graduate Group in Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
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10
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Kulkarni HS, Scozzi D, Gelman AE. Recent advances into the role of pattern recognition receptors in transplantation. Cell Immunol 2020; 351:104088. [PMID: 32183988 DOI: 10.1016/j.cellimm.2020.104088] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 12/19/2022]
Abstract
Pattern recognition receptors (PRRs) are germline-encoded sensors best characterized for their critical role in host defense. However, there is accumulating evidence that organ transplantation induces the release or display of molecular patterns of cellular injury and death that trigger PRR-mediated inflammatory responses. There are also new insights that indicate PRRs are able to distinguish between self and non-self, suggesting the existence of non-clonal mechanisms of allorecognition. Collectively, these reports have spurred considerable interest into whether PRRs or their ligands can be targeted to promote transplant survival. This review examines the mounting evidence that PRRs play in transplant-mediated inflammation. Given the large number of PRRs, we will focus on members from four families: the complement system, toll-like receptors, the formylated peptide receptor, and scavenger receptors through examining reports of their activity in experimental models of cellular and solid organ transplantation as well as in the clinical setting.
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Affiliation(s)
- Hrishikesh S Kulkarni
- Department of Medicine, Division of Pulmonary & Critical Care Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Davide Scozzi
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Andrew E Gelman
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA; Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO, USA.
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11
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Hayes BH, Tsai RK, Dooling LJ, Kadu S, Lee JY, Pantano D, Rodriguez PL, Subramanian S, Shin JW, Discher DE. Macrophages show higher levels of engulfment after disruption of cis interactions between CD47 and the checkpoint receptor SIRPα. J Cell Sci 2020; 133:jcs.237800. [PMID: 31964705 DOI: 10.1242/jcs.237800] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/20/2019] [Indexed: 12/14/2022] Open
Abstract
The macrophage checkpoint receptor SIRPα signals against phagocytosis by binding CD47 expressed on all cells - including macrophages. Here, we found that inhibiting cis interactions between SIRPα and CD47 on the same macrophage increased engulfment ('eating') by approximately the same level as inhibiting trans interactions. Antibody blockade of CD47, as pursued in clinical trials against cancer, was applied separately to human-derived macrophages and to red blood cell (RBC) targets for phagocytosis, and both scenarios produced surprisingly similar increases in RBC engulfment. Blockade of both macrophages and targets resulted in hyper-phagocytosis, and knockdown of macrophage-CD47 likewise increased engulfment of 'foreign' cells and particles, decreased the baseline inhibitory signaling of SIRPα, and linearly increased binding of soluble CD47 in trans, consistent with cis-trans competition. Many cell types express both SIRPα and CD47, including mouse melanoma B16 cells, and CRISPR-mediated deletions modulate B16 phagocytosis, consistent with cis-trans competition. Additionally, soluble SIRPα binding to human CD47 displayed on Chinese hamster ovary (CHO) cells was suppressed by SIRPα co-display, and atomistic computations confirm SIRPα bends and binds CD47 in cis Safety and efficacy profiles for CD47-SIRPα blockade might therefore reflect a disruption of both cis and trans interactions.
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Affiliation(s)
- Brandon H Hayes
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Group in Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Richard K Tsai
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Group in Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lawrence J Dooling
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Siddhant Kadu
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Justine Y Lee
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Diego Pantano
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Pia L Rodriguez
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Jae-Won Shin
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Group in Pharmacology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dennis E Discher
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Group in Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Group in Pharmacology, University of Pennsylvania, Philadelphia, PA 19104, USA
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12
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Jain S, Van Scoyk A, Morgan EA, Matthews A, Stevenson K, Newton G, Powers F, Autio A, Louissaint A, Pontini G, Aster JC, Luscinskas FW, Weinstock DM. Targeted inhibition of CD47-SIRPα requires Fc-FcγR interactions to maximize activity in T-cell lymphomas. Blood 2019; 134:1430-1440. [PMID: 31383641 PMCID: PMC6839960 DOI: 10.1182/blood.2019001744] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/30/2019] [Indexed: 12/21/2022] Open
Abstract
Antibodies that bind CD47 on tumor cells and prevent interaction with SIRPα on phagocytes are active against multiple cancer types including T-cell lymphoma (TCL). Here we demonstrate that surface CD47 is heterogeneously expressed across primary TCLs, whereas major histocompatibility complex (MHC) class I, which can also suppress phagocytosis, is ubiquitous. Multiple monoclonal antibodies (mAbs) that block CD47-SIRPα interaction promoted phagocytosis of TCL cells, which was enhanced by cotreatment with antibodies targeting MHC class I. Expression levels of surface CD47 and genes that modulate CD47 pyroglutamation did not correlate with the extent of phagocytosis induced by CD47 blockade in TCL lines. In vivo treatment of multiple human TCL patient-derived xenografts or an immunocompetent murine TCL model with a short course of anti-CD47 mAb markedly reduced lymphoma burden and extended survival. Depletion of macrophages reduced efficacy in vivo, whereas depletion of neutrophils had no effect. F(ab')2-only fragments of anti-CD47 antibodies failed to induce phagocytosis by human macrophages, indicating a requirement for Fc-Fcγ receptor interactions. In contrast, F(ab')2-only fragments increased phagocytosis by murine macrophages independent of SLAMF7-Mac-1 interaction. Full-length anti-CD47 mAbs also induced phagocytosis by Fcγ receptor-deficient murine macrophages. An immunoglobulin G1 anti-CD47 mAb induced phagocytosis and natural killer cell-mediated cytotoxicity of TCL cells that was augmented by cotreatment with mogamulizumab, an anti-CCR4 mAb, or a mAb blocking MHC class I. These studies help explain the disparate activity of monotherapy with agents that block CD47 in murine models compared with patients. They also have direct translational implications for the deployment of anti-CD47 mAbs alone or in combination.
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MESH Headings
- Animals
- Antigens, Differentiation/immunology
- Antineoplastic Agents, Immunological/pharmacology
- Antineoplastic Agents, Immunological/therapeutic use
- CD47 Antigen/antagonists & inhibitors
- CD47 Antigen/immunology
- Cell Line, Tumor
- Humans
- Lymphoma, T-Cell/drug therapy
- Lymphoma, T-Cell/immunology
- Lymphoma, T-Cell/pathology
- Mice
- Receptors, Fc/immunology
- Receptors, IgG/immunology
- Receptors, Immunologic/immunology
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Affiliation(s)
- Salvia Jain
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA
- Harvard Medical School, Boston, MA
| | - Alexandria Van Scoyk
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
- Department of Oncological Sciences, University of Utah, Salt Lake City, UT
| | - Elizabeth A Morgan
- Harvard Medical School, Boston, MA
- Department of Pathology, Brigham and Women's Hospital, Boston, MA
| | - Andrew Matthews
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA
| | - Kristen Stevenson
- Department of Computational Biology and Biostatistics, Dana-Farber Cancer Institute, Boston, MA
| | - Gail Newton
- Department of Pathology, Brigham and Women's Hospital, Boston, MA
| | - Foster Powers
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Anu Autio
- Department of Pathology, Brigham and Women's Hospital, Boston, MA
| | - Abner Louissaint
- Harvard Medical School, Boston, MA
- Department of Pathology, Massachusetts General Hospital, Boston, MA
| | | | - Jon C Aster
- Harvard Medical School, Boston, MA
- Department of Pathology, Brigham and Women's Hospital, Boston, MA
| | - Francis W Luscinskas
- Harvard Medical School, Boston, MA
- Department of Pathology, Brigham and Women's Hospital, Boston, MA
| | - David M Weinstock
- Harvard Medical School, Boston, MA
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
- Broad Institute of Harvard and MIT, Cambridge, MA
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13
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Miller TW, Amason JD, Garcin ED, Lamy L, Dranchak PK, Macarthur R, Braisted J, Rubin JS, Burgess TL, Farrell CL, Roberts DD, Inglese J. Quantitative high-throughput screening assays for the discovery and development of SIRPα-CD47 interaction inhibitors. PLoS One 2019; 14:e0218897. [PMID: 31276567 PMCID: PMC6611588 DOI: 10.1371/journal.pone.0218897] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 06/11/2019] [Indexed: 02/06/2023] Open
Abstract
CD47 is an immune checkpoint molecule that downregulates key aspects of both the innate and adaptive anti-tumor immune response via its counter receptor SIRPα, and it is expressed at high levels in a wide variety of tumor types. This has led to the development of biologics that inhibit SIRPα engagement including humanized CD47 antibodies and a soluble SIRPα decoy receptor that are currently undergoing clinical trials. Unfortunately, toxicological issues, including anemia related to on-target mechanisms, are barriers to their clinical advancement. Another potential issue with large biologics that bind CD47 is perturbation of CD47 signaling through its high-affinity interaction with the matricellular protein thrombospondin-1 (TSP1). One approach to avoid these shortcomings is to identify and develop small molecule molecular probes and pretherapeutic agents that would (1) selectively target SIRPα or TSP1 interactions with CD47, (2) provide a route to optimize pharmacokinetics, reduce on-target toxicity and maximize tissue penetration, and (3) allow more flexible routes of administration. As the first step toward this goal, we report the development of an automated quantitative high-throughput screening (qHTS) assay platform capable of screening large diverse drug-like chemical libraries to discover novel small molecules that inhibit CD47-SIRPα interaction. Using time-resolved Förster resonance energy transfer (TR-FRET) and bead-based luminescent oxygen channeling assay formats (AlphaScreen), we developed biochemical assays, optimized their performance, and individually tested them in small-molecule library screening. Based on performance and low false positive rate, the LANCE TR-FRET assay was employed in a ~90,000 compound library qHTS, while the AlphaScreen oxygen channeling assay served as a cross-validation orthogonal assay for follow-up characterization. With this multi-assay strategy, we successfully eliminated compounds that interfered with the assays and identified five compounds that inhibit the CD47-SIRPα interaction; these compounds will be further characterized and later disclosed. Importantly, our results validate the large library qHTS for antagonists of CD47-SIRPα interaction and suggest broad applicability of this approach to screen chemical libraries for other protein-protein interaction modulators.
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Affiliation(s)
- Thomas W. Miller
- Paradigm Shift Therapeutics LLC, Rockville, Maryland, United States of America
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Joshua D. Amason
- Paradigm Shift Therapeutics LLC, Rockville, Maryland, United States of America
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Elsa D. Garcin
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Catonsville, Maryland, United States of America
| | - Laurence Lamy
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Patricia K. Dranchak
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Ryan Macarthur
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - John Braisted
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Jeffrey S. Rubin
- Paradigm Shift Therapeutics LLC, Rockville, Maryland, United States of America
| | - Teresa L. Burgess
- Paradigm Shift Therapeutics LLC, Rockville, Maryland, United States of America
| | | | - David D. Roberts
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - James Inglese
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
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14
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Alfayez M, Borthakur G. Checkpoint inhibitors and acute myelogenous leukemia: promises and challenges. Expert Rev Hematol 2019; 11:373-389. [PMID: 29589969 DOI: 10.1080/17474086.2018.1459184] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Immunity, for treatment of acute myelogenous leukemia (AML), has been leveraged historically in the form of allogeneic stem cell transplantation. Checkpoint inhibitors (CPI) as positive modulators of immune response have been recent major breakthroughs in solid tumors. Areas covered: Emerging concepts and clinical data with CPIs in acute Myeloid Leukemia - the focus of this review- will be discussed. CPIs can potentially be effective in absence of 'actionable' mutations and are expected to be effective against poor-risk AML. Immune inhibitory checkpoint molecules are upregulated in both de novo and relapsed AML. Similar data also suggest role of checkpoint molecules in mediating resistance particularly to hypomethylating agent (HMA) therapy, which can potentially be reversed by using checkpoint inhibitors. Expert commentary: Ongoing clinical trials in combination with HMAs are showing early promise, with doubling of response than that seen in historic controls. The optimal combinations of CPIs and the optimal space that they will fit in the continuum of AML therapies need lot of in depth work.
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Affiliation(s)
- Mansour Alfayez
- a Department of Leukemia , University of Texas M. D. Anderson Cancer Center , Houston , TX , USA
| | - Gautam Borthakur
- a Department of Leukemia , University of Texas M. D. Anderson Cancer Center , Houston , TX , USA
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15
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Wang Y, Wang Z, Qian Y, Fan L, Yue C, Jia F, Sun J, Hu Z, Wang W. Synergetic estrogen receptor-targeting liposome nanocarriers with anti-phagocytic properties for enhanced tumor theranostics. J Mater Chem B 2019; 7:1056-1063. [DOI: 10.1039/c8tb03351j] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A synergetic targeted liposomal system which functionalized with both a tumor identification ligand and an immune targeting ligand was constructed. It could recognize and bind ER-positive breast cancer tissues in a specific way and reduce the macrophage phagocytosis of the nanoparticles.
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Affiliation(s)
- Yuehua Wang
- School of Pharmaceutical Science and Technology
- Health Science Platform
- Tianjin University
- Tianjin 300072
- China
| | - Zihua Wang
- CAS Key Laboratory of Colloid
- Interface and Chemical Thermodynamics
- Institute of Chemistry Chinese Academy of Sciences
- Beijing 100190
- China
| | - Yixia Qian
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
| | - Linyang Fan
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
| | - Chunyan Yue
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
| | - Fei Jia
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
| | - Jian Sun
- School of Pharmaceutical Science and Technology
- Health Science Platform
- Tianjin University
- Tianjin 300072
- China
| | - Zhiyuan Hu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
| | - Weizhi Wang
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- CAS Center for Excellence in Nanoscience
- National Center for Nanoscience and Technology of China
- Beijing 100190
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16
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Steinkühler J, Różycki B, Alvey C, Lipowsky R, Weikl TR, Dimova R, Discher DE. Membrane fluctuations and acidosis regulate cooperative binding of 'marker of self' protein CD47 with the macrophage checkpoint receptor SIRPα. J Cell Sci 2018; 132:jcs.216770. [PMID: 29777034 DOI: 10.1242/jcs.216770] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022] Open
Abstract
Cell-cell interactions that result from membrane proteins binding weakly in trans can cause accumulations in cis that suggest cooperativity and thereby an acute sensitivity to environmental factors. The ubiquitous 'marker of self' protein CD47 binds weakly to SIRPα on macrophages, which leads to accumulation of SIRPα (also known as SHPS-1, CD172A and SIRPA) at phagocytic synapses and ultimately to inhibition of engulfment of 'self' cells - including cancer cells. We reconstituted this macrophage checkpoint with GFP-tagged CD47 on giant vesicles generated from plasma membranes and then imaged vesicles adhering to SIRPα immobilized on a surface. CD47 diffusion is impeded near the surface, and the binding-unbinding events reveal cooperative interactions as a concentration-dependent two-dimensional affinity. Membrane fluctuations out-of-plane link cooperativity to membrane flexibility with suppressed fluctuations in the vicinity of bound complexes. Slight acidity (pH 6) stiffens membranes, diminishes cooperative interactions and also reduces 'self' signaling of cancer cells in phagocytosis. Sensitivity of cell-cell interactions to microenvironmental factors - such as the acidity of tumors and other diseased or inflamed sites - can thus arise from the collective cooperative properties of flexible membranes.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jan Steinkühler
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, 19104 PA, USA.,Theory and Bio-Systems, Max Planck Institut of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Bartosz Różycki
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Cory Alvey
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, 19104 PA, USA
| | - Reinhard Lipowsky
- Theory and Bio-Systems, Max Planck Institut of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Thomas R Weikl
- Theory and Bio-Systems, Max Planck Institut of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Rumiana Dimova
- Theory and Bio-Systems, Max Planck Institut of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Dennis E Discher
- Molecular & Cell Biophysics Lab, University of Pennsylvania, Philadelphia, 19104 PA, USA
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17
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Aoki T. A Comprehensive Review of Our Current Understanding of Red Blood Cell (RBC) Glycoproteins. MEMBRANES 2017; 7:membranes7040056. [PMID: 28961212 PMCID: PMC5746815 DOI: 10.3390/membranes7040056] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 09/20/2017] [Accepted: 09/24/2017] [Indexed: 12/11/2022]
Abstract
Human red blood cells (RBC), which are the cells most commonly used in the study of biological membranes, have some glycoproteins in their cell membrane. These membrane proteins are band 3 and glycophorins A-D, and some substoichiometric glycoproteins (e.g., CD44, CD47, Lu, Kell, Duffy). The oligosaccharide that band 3 contains has one N-linked oligosaccharide, and glycophorins possess mostly O-linked oligosaccharides. The end of the O-linked oligosaccharide is linked to sialic acid. In humans, this sialic acid is N-acetylneuraminic acid (NeuAc). Another sialic acid, N-glycolylneuraminic acid (NeuGc) is present in red blood cells of non-human origin. While the biological function of band 3 is well known as an anion exchanger, it has been suggested that the oligosaccharide of band 3 does not affect the anion transport function. Although band 3 has been studied in detail, the physiological functions of glycophorins remain unclear. This review mainly describes the sialo-oligosaccharide structures of band 3 and glycophorins, followed by a discussion of the physiological functions that have been reported in the literature to date. Moreover, other glycoproteins in red blood cell membranes of non-human origin are described, and the physiological function of glycophorin in carp red blood cell membranes is discussed with respect to its bacteriostatic activity.
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Affiliation(s)
- Takahiko Aoki
- Laboratory of Quality in Marine Products, Graduate School of Bioresources, Mie University, 1577 Kurima Machiya-cho, Mie, Tsu 514-8507, Japan.
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18
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Dai H, Friday AJ, Abou-Daya KI, Williams AL, Mortin-Toth S, Nicotra ML, Rothstein DM, Shlomchik WD, Matozaki T, Isenberg JS, Oberbarnscheidt MH, Danska JS, Lakkis FG. Donor SIRPα polymorphism modulates the innate immune response to allogeneic grafts. Sci Immunol 2017; 2:2/12/eaam6202. [PMID: 28783664 DOI: 10.1126/sciimmunol.aam6202] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 05/15/2017] [Indexed: 12/16/2022]
Abstract
Mice devoid of T, B, and natural killer (NK) cells distinguish between self and allogeneic nonself despite the absence of an adaptive immune system. When challenged with an allograft, they mount an innate response characterized by accumulation of mature, monocyte-derived dendritic cells (DCs) that produce interleukin-12 and present antigen to T cells. However, the molecular mechanisms by which the innate immune system detects allogeneic nonself to generate these DCs are not known. To address this question, we studied the innate response of Rag2-/- γc-/- mice, which lack T, B, and NK cells, to grafts from allogeneic donors. By positional cloning, we identified that donor polymorphism in the gene encoding signal regulatory protein α (SIRPα) is a key modulator of the recipient's innate allorecognition response. Donors that differed from the recipient in one or both Sirpa alleles elicited an innate alloresponse. The response was mediated by binding of donor SIRPα to recipient CD47 and was modulated by the strength of the SIRPα-CD47 interaction. Therefore, sensing SIRPα polymorphism by CD47 provides a molecular mechanism by which the innate immune system distinguishes between self and allogeneic nonself independently of T, B, and NK cells.
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Affiliation(s)
- Hehua Dai
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Andrew J Friday
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Khodor I Abou-Daya
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Amanda L Williams
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Steven Mortin-Toth
- Program in Genetics and Genome Biology, Hospital for Sick Children Research Institute, Toronto, Ontario M5G1X8, Canada
| | - Matthew L Nicotra
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - David M Rothstein
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Warren D Shlomchik
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Takashi Matozaki
- Division of Molecular and Cellular Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Kobe 650-0017, Japan
| | - Jeffrey S Isenberg
- Heart, Lung, Blood, and Vascular Medicine Institute and Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Martin H Oberbarnscheidt
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Program in Genetics and Genome Biology, Hospital for Sick Children Research Institute, Toronto, Ontario M5G1X8, Canada
| | - Jayne S Danska
- Program in Genetics and Genome Biology, Hospital for Sick Children Research Institute, Toronto, Ontario M5G1X8, Canada. .,Departments of Immunology and Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S1A8, Canada
| | - Fadi G Lakkis
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA. .,Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.,Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
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19
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Prolonged Survival of Pig Skin on Baboons After Administration of Pig Cells Expressing Human CD47. Transplantation 2017; 101:316-321. [PMID: 27232934 DOI: 10.1097/tp.0000000000001267] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Successful xenotransplantation will likely depend, in part, on the induction of immunological tolerance, because the high levels of immunosuppression otherwise required would likely have unacceptable side effects. Rapid clearance of administered porcine hematopoietic stem cells by primate macrophages has hampered previous attempts to induce tolerance through mixed hematopoietic chimerism across a pig-to-primate barrier. Phagocytosis is normally inhibited by binding of cell surface protein CD47 to macrophage signal regulatory protein α receptors. However, pig CD47 has previously been shown to be ineffective in transducing signals through primate signal regulatory protein α. METHODS Mobilized peripheral blood hematopoietic cells from transgenic swine expressing high or low levels of human CD47 were infused into conditioned baboons at 3 time points over a 9-week period. Xenogeneic peripheral blood chimerism was assessed after each infusion. Split thickness skin grafts from the hematopoietic cell donor swine were placed on recipients 5 weeks after the last cell infusion and 7 weeks after the discontinuation of all immunosuppression to test immune response. RESULTS The level and duration of transient chimerism were substantially greater in baboons receiving hematopoietic cells from a pig expressing high levels of human CD47. Skin graft survival on high CD47 recipients was prolonged as well, in 1 case showing no signs of rejection at least 53 days after placement. CONCLUSIONS Prolongation of transient porcine chimerism via transgenic expression of human CD47 in a primate model is associated with an immune modulating effect, leading to markedly prolonged survival of donor swine skin xenografts that may be applicable to clinical solid organ xenotransplantation.
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20
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Flies AS, Blackburn NB, Lyons AB, Hayball JD, Woods GM. Comparative Analysis of Immune Checkpoint Molecules and Their Potential Role in the Transmissible Tasmanian Devil Facial Tumor Disease. Front Immunol 2017; 8:513. [PMID: 28515726 PMCID: PMC5413580 DOI: 10.3389/fimmu.2017.00513] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 04/18/2017] [Indexed: 12/13/2022] Open
Abstract
Immune checkpoint molecules function as a system of checks and balances that enhance or inhibit immune responses to infectious agents, foreign tissues, and cancerous cells. Immunotherapies that target immune checkpoint molecules, particularly the inhibitory molecules programmed cell death 1 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), have revolutionized human oncology in recent years, yet little is known about these key immune signaling molecules in species other than primates and rodents. The Tasmanian devil facial tumor disease is caused by transmissible cancers that have resulted in a massive decline in the wild Tasmanian devil population. We have recently demonstrated that the inhibitory checkpoint molecule PD-L1 is upregulated on Tasmanian devil (Sarcophilus harrisii) facial tumor cells in response to the interferon-gamma cytokine. As this could play a role in immune evasion by tumor cells, we performed a thorough comparative analysis of checkpoint molecule protein sequences among Tasmanian devils and eight other species. We report that many of the key signaling motifs and ligand-binding sites in the checkpoint molecules are highly conserved across the estimated 162 million years of evolution since the last common ancestor of placental and non-placental mammals. Specifically, we discovered that the CTLA-4 (MYPPPY) ligand-binding motif and the CTLA-4 (GVYVKM) inhibitory domain are completely conserved across all nine species used in our comparative analysis, suggesting that the function of CTLA-4 is likely conserved in these species. We also found that cysteine residues for intra- and intermolecular disulfide bonds were also highly conserved. For instance, all 20 cysteine residues involved in disulfide bonds in the human 4-1BB molecule were also present in devil 4-1BB. Although many key sequences were conserved, we have also identified immunoreceptor tyrosine-based inhibitory motifs (ITIMs) and immunoreceptor tyrosine-based switch motifs (ITSMs) in genes and protein domains that have not been previously reported in any species. This checkpoint molecule analysis and review of salient features for each of the molecules presented here can serve as road map for the development of a Tasmanian devil facial tumor disease immunotherapy. Finally, the strategies can be used as a guide for veterinarians, ecologists, and other researchers willing to venture into the nascent field of wild immunology.
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Affiliation(s)
- Andrew S. Flies
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
- Department of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia
| | - Nicholas B. Blackburn
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
- School of Medicine, South Texas Diabetes and Obesity Institute, University of Texas Rio Grande Valley, Brownsville, TX, USA
| | - Alan Bruce Lyons
- School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - John D. Hayball
- Department of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia
- Discipline of Obstetrics and Gynaecology, School of Medicine, Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Gregory M. Woods
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
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21
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Ma YH, Dou WT, Pan YF, Dong LW, Tan YX, He XP, Tian H, Wang HY. Fluorogenic 2D Peptidosheet Unravels CD47 as a Potential Biomarker for Profiling Hepatocellular Carcinoma and Cholangiocarcinoma Tissues. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1604253. [PMID: 27869342 DOI: 10.1002/adma.201604253] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/21/2016] [Indexed: 06/06/2023]
Abstract
A 2D peptidosheet unravels CD47 as a potential biomarker to image hepatocarcinoma and cholangiocarcinoma cells and tissues. Supramolecular assembly between water-soluble 2D MoS2 and a peptide probe produces the 2D peptidosheet suited for the profiling of hepatocarcinoma and cholangiocarcinoma tissues over healthy tissues on clinical specimens.
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Affiliation(s)
- Yun-Han Ma
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, the Second Military Medical University, Shanghai, 200433, P. R. China
| | - Wei-Tao Dou
- Key Laboratory for Advanced Materials & Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Rd., Shanghai, 200237, P. R. China
| | - Yu-Fei Pan
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, the Second Military Medical University, Shanghai, 200433, P. R. China
| | - Li-Wei Dong
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, the Second Military Medical University, Shanghai, 200433, P. R. China
| | - Ye-Xiong Tan
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, the Second Military Medical University, Shanghai, 200433, P. R. China
| | - Xiao-Peng He
- Key Laboratory for Advanced Materials & Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Rd., Shanghai, 200237, P. R. China
| | - He Tian
- Key Laboratory for Advanced Materials & Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Rd., Shanghai, 200237, P. R. China
| | - Hong-Yang Wang
- International Cooperation Laboratory on Signal Transduction, Eastern Hepatobiliary Surgery Institute, the Second Military Medical University, Shanghai, 200433, P. R. China
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22
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Huang Y, Ma Y, Gao P, Yao Z. Targeting CD47: the achievements and concerns of current studies on cancer immunotherapy. J Thorac Dis 2017; 9:E168-E174. [PMID: 28275508 PMCID: PMC5334085 DOI: 10.21037/jtd.2017.02.30] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 01/22/2017] [Indexed: 02/04/2023]
Abstract
Targeting CD47 is in the spotlight of cancer immunotherapy. Blocking CD47 triggers the recognition and elimination of cancer cells by the innate immunity. There are three CD47 antagonists in phase I clinical trials, but their potential efficacies are highly controversial. We raise our concern that NOD-based xenograft hosts tend to overestimate, while syngeneic mouse models could substantially underestimate the efficacy of anti-CD47 therapy. Such discrepancy may be resulted from specific reagent that alters CD47 clustering, and the highly variable avidities of interspecies and intraspecies CD47-SIRPα interaction. This problem can be addressed by alternative animal models for better recapitulation of human CD47-SIRPα interaction. Both fragment crystallizable (Fc) fragment-dependent effects, like antibody-dependent cell-mediated cytotoxicity (ADCC), and Fc-independent CD47 intrinsic functions are involved in anti-CD47 therapy. The latter may be SIRPα-dependent or SIRPα-independent, such as the case of calreticulin. It has not reached a consensus which of the factors predominate the process, but the answer to this question will determine the optimal pharmaceutical and clinical design of CD47 targeting strategies.
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Affiliation(s)
- Yuting Huang
- Department of Immunology, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Educational Ministry of China, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300071, China
| | - Yuchi Ma
- Center for Molecular Medicine, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Peng Gao
- University of the District of Columbia, Washington D.C., USA
| | - Zhi Yao
- Department of Immunology, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Educational Ministry of China, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300071, China
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23
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Sosale NG, Ivanovska II, Tsai RK, Swift J, Hsu JW, Alvey CM, Zoltick PW, Discher DE. "Marker of Self" CD47 on lentiviral vectors decreases macrophage-mediated clearance and increases delivery to SIRPA-expressing lung carcinoma tumors. Mol Ther Methods Clin Dev 2016; 3:16080. [PMID: 28053997 PMCID: PMC5148596 DOI: 10.1038/mtm.2016.80] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 10/05/2016] [Accepted: 10/06/2016] [Indexed: 02/08/2023]
Abstract
Lentiviruses infect many cell types and are now widely used for gene delivery in vitro, but in vivo uptake of these foreign vectors by macrophages is a limitation. Lentivectors are produced here from packaging cells that overexpress "Marker of Self" CD47, which inhibits macrophage uptake of cells when prophagocytic factors are also displayed. Single particle analyses show "hCD47-Lenti" display properly oriented human-CD47 for interactions with the macrophage's inhibitory receptor SIRPA. Macrophages derived from human and NOD/SCID/Il2rg-/- (NSG) mice show a SIRPA-dependent decrease in transduction, i.e., transgene expression, by hCD47-Lenti compared to control Lenti. Consistent with known "Self" signaling pathways, macrophage transduction by control Lenti is decreased by drug inhibition of Myosin-II to the same levels as hCD47-Lenti. In contrast, human lung carcinoma cells express SIRPA and use it to enhance transduction by hCD47-Lenti- as illustrated by more efficient gene deletion using CRISPR/Cas9. Intravenous injection of hCD47-Lenti into NSG mice shows hCD47 prolongs circulation, unless a blocking anti-SIRPA is preinjected. In vivo transduction of spleen and liver macrophages also decreases for hCD47-Lenti while transduction of lung carcinoma xenografts increases. hCD47 could be useful when macrophage uptake is limiting on other viral vectors that are emerging in cancer treatments (e.g., Measles glycoprotein-pseudotyped lentivectors) and also in targeting various SIRPA-expressing tumors such as glioblastomas.
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Affiliation(s)
- Nisha G Sosale
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Irena I Ivanovska
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Richard K Tsai
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Joe Swift
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jake W Hsu
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Cory M Alvey
- Pharmacological Sciences Graduate Group, University of Pennsylvania, Pennsylvania, USA
| | - Philip W Zoltick
- Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Dennis E Discher
- Biophysical Engineering Labs, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Pharmacological Sciences Graduate Group, University of Pennsylvania, Pennsylvania, USA
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Caston SS, Cooper EE, Chandramani-Shivalingappa P, Sponseller BA, Hostetter JM, Sun Y. CD47 expression in cryopreserved equine cutaneous masses and normal skin. J Vet Diagn Invest 2016; 28:408-13. [PMID: 27154320 DOI: 10.1177/1040638716643352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We investigated CD47 expression in cryopreserved sections of equine cutaneous masses and normal skin. CD47 is a cell surface protein expressed on many cell types and overexpressed in some tumors. Interaction of CD47 and signal regulatory protein-alpha (SIRPα) inhibits phagocytosis by macrophages. Formalin-fixed tissues from horses prospectively enrolled in the study were used to establish a histologic diagnosis. Immunohistochemical assays were performed on cryopreserved tissues using anti-CD47 antibodies or IgG control antibodies. CD47 was not expressed on equine normal skin but positivity to CD47 was present in 13 of 24 (54%) masses. Immunotherapy with anti-CD47 antibodies for equine cutaneous tumors that express CD47 warrants further investigation.
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Affiliation(s)
- Stephanie S Caston
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
| | - Elizabeth E Cooper
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
| | - Prashanth Chandramani-Shivalingappa
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
| | - Brett A Sponseller
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
| | - Jesse M Hostetter
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
| | - Yaxuan Sun
- Departments of Veterinary Clinical Sciences (Caston, Cooper), Iowa State University, Ames, IAVeterinary Microbiology and Preventive Medicine (Chandramani-Shivalingappa, Sponseller), Iowa State University, Ames, IAVeterinary Pathology (Hostetter), Iowa State University, Ames, IACollege of Veterinary Medicine, and Department of Statistics (Sun), Iowa State University, Ames, IA
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25
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Curran E, Corrales L, Kline J. Targeting the innate immune system as immunotherapy for acute myeloid leukemia. Front Oncol 2015; 5:83. [PMID: 25914882 PMCID: PMC4391043 DOI: 10.3389/fonc.2015.00083] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/21/2015] [Indexed: 01/05/2023] Open
Abstract
Because of its disseminated nature and lack of tumor-draining lymph nodes, acute myeloid leukemia (AML) likely employs unique immune evasion strategies as compared to solid malignancies. Targeting these unique mechanisms may result in improved immunotherapeutic approaches. Emerging data suggest that a specific dendritic cell (DC) subset, CD8α DCs, may be responsible for mediating tolerance in AML and thus targeting the innate immune system may be of benefit in this disease. Promising immune targets include the toll-like receptors, calreticulin/CD47, the stimulator of interferon genes pathway, and signal transducer and activator of transcription 3 (STAT3). However, it is becoming clear that compensatory mechanisms may limit the efficacy of these agents alone and thus rationale combinations of immunotherapies are warranted. This review discusses the potential immune evasion strategies in AML, as well as discussion of the promising innate immune targets, both alone and in combination, for this disease.
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Affiliation(s)
- Emily Curran
- Department of Medicine, University of Chicago , Chicago, IL , USA
| | - Leticia Corrales
- Department of Pathology, University of Chicago , Chicago, IL , USA ; Committee on Immunology, University of Chicago , Chicago, IL , USA
| | - Justin Kline
- Department of Medicine, University of Chicago , Chicago, IL , USA ; Committee on Immunology, University of Chicago , Chicago, IL , USA ; University of Chicago Comprehensive Cancer Center , Chicago, IL , USA
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26
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Soto-Pantoja DR, Kaur S, Roberts DD. CD47 signaling pathways controlling cellular differentiation and responses to stress. Crit Rev Biochem Mol Biol 2015; 50:212-30. [PMID: 25708195 DOI: 10.3109/10409238.2015.1014024] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CD47 is a widely expressed integral membrane protein that serves as the counter-receptor for the inhibitory phagocyte receptor signal-regulatory protein-α (SIRPα) and as a signaling receptor for the secreted matricellular protein thrombospondin-1. Recent studies employing mice and somatic cells lacking CD47 have revealed important pathophysiological functions of CD47 in cardiovascular homeostasis, immune regulation, resistance of cells and tissues to stress and chronic diseases of aging including cancer. With the emergence of experimental therapeutics targeting CD47, a more thorough understanding of CD47 signal transduction is essential. CD47 lacks a substantial cytoplasmic signaling domain, but several cytoplasmic binding partners have been identified, and lateral interactions of CD47 with other membrane receptors play important roles in mediating signaling resulting from the binding of thrombospondin-1. This review addresses recent advances in identifying the lateral binding partners, signal transduction pathways and downstream transcription networks regulated through CD47 in specific cell lineages. Major pathways regulated by CD47 signaling include calcium homeostasis, cyclic nucleotide signaling, nitric oxide and hydrogen sulfide biosynthesis and signaling and stem cell transcription factors. These pathways and other undefined proximal mediators of CD47 signaling regulate cell death and protective autophagy responses, mitochondrial biogenesis, cell adhesion and motility and stem cell self-renewal. Although thrombospondin-1 is the best characterized agonist of CD47, the potential roles of other members of the thrombospondin family, SIRPα and SIRPγ binding and homotypic CD47 interactions as agonists or antagonists of signaling through CD47 should also be considered.
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Affiliation(s)
- David R Soto-Pantoja
- a Laboratory of Pathology , Center for Cancer Research, National Cancer Institute, National Institutes of Health , Bethesda , MD , USA
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Tena A, Kurtz J, Leonard DA, Dobrinsky JR, Terlouw SL, Mtango N, Verstegen J, Germana S, Mallard C, Arn JS, Sachs DH, Hawley RJ. Transgenic expression of human CD47 markedly increases engraftment in a murine model of pig-to-human hematopoietic cell transplantation. Am J Transplant 2014; 14:2713-22. [PMID: 25278264 PMCID: PMC4236244 DOI: 10.1111/ajt.12918] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/16/2014] [Accepted: 07/06/2014] [Indexed: 01/25/2023]
Abstract
Mixed chimerism approaches for induction of tolerance of solid organ transplants have been applied successfully in animal models and in the clinic. However, in xenogeneic models (pig-to-primate), host macrophages participate in the rapid clearance of porcine hematopoietic progenitor cells, hindering the ability to achieve mixed chimerism. CD47 is a cell-surface molecule that interacts in a species-specific manner with SIRPα receptors on macrophages to inhibit phagocytosis and expression of human CD47 (hCD47) on porcine cells has been shown to inhibit phagocytosis by primate macrophages. We report here the generation of hCD47 transgenic GalT-KO miniature swine that express hCD47 in all blood cell lineages. The effect of hCD47 expression on xenogeneic hematopoietic engraftment was tested in an in vivo mouse model of human hematopoietic cell engraftment. High-level porcine chimerism was observed in the bone marrow of hCD47 progenitor cell recipients and smaller but readily measurable chimerism levels were observed in the peripheral blood of these recipients. In contrast, transplantation of WT progenitor cells resulted in little or no bone marrow engraftment and no detectable peripheral chimerism. These results demonstrate a substantial protective effect of hCD47 expression on engraftment and persistence of porcine cells in this model, presumably by modulation of macrophage phagocytosis.
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Affiliation(s)
- Aseda Tena
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Josef Kurtz
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA,Department of Biology, Emmanuel College, Boston, MA
| | - David A. Leonard
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | | | | | | | | | - Sharon Germana
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Christopher Mallard
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - J. Scott Arn
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - David H. Sachs
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
| | - Robert J. Hawley
- Transplantation Biology Research Center, Massachusetts General Hospital, Boston, MA
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Barclay AN, van den Berg TK. The Interaction Between Signal Regulatory Protein Alpha (SIRPα) and CD47: Structure, Function, and Therapeutic Target. Annu Rev Immunol 2014; 32:25-50. [DOI: 10.1146/annurev-immunol-032713-120142] [Citation(s) in RCA: 448] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Neil Barclay
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK;
| | - Timo K. van den Berg
- Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1066 CX Amsterdam, The Netherlands;
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29
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Murata Y, Kotani T, Ohnishi H, Matozaki T. The CD47-SIRPα signalling system: its physiological roles and therapeutic application. J Biochem 2014; 155:335-44. [PMID: 24627525 DOI: 10.1093/jb/mvu017] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Signal regulatory protein α (SIRPα), also known as SHPS-1/BIT/ CD172a, is an immunoglobulin superfamily protein that binds to the protein tyrosine phosphatases SHP-1 and SHP-2 through its cytoplasmic region. CD47, another immunoglobulin superfamily protein, is a ligand for SIRPα, with the two proteins constituting a cell-cell communication system (the CD47-SIRPα signalling system). SIRPα is particularly abundant in the myeloid-lineage hematopoietic cells such as macrophages or dendritic cells (DCs), whereas CD47 is expressed ubiquitously. Interaction of CD47 (on red blood cells) with SIRPα (on macrophages) is thought to prevent the phagocytosis by the latter cells of the former cells, determining the lifespan of red blood cells. Recent studies further indicate that this signalling system plays important roles in engraftment of hematopoietic stem cells as well as in tumour immune surveillance through regulation of the phagocytic activity of macrophages. In the immune system, the CD47-SIRPα interaction is also important for the development of a subset of CD11c(+)DCs as well as organization of secondary lymphoid organs. Finally, the CD47-SIRPα signalling system likely regulates bone homeostasis by osteoclast development. Newly emerged functions of the CD47-SIRPα signalling system thus provide multiple therapeutic strategies for cancer, autoimmune diseases and bone disorders.
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Affiliation(s)
- Yoji Murata
- Department of Biochemistry and Molecular Biology, Division of Molecular and Cellular Signaling, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; and Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8514, Japan
| | - Takenori Kotani
- Department of Biochemistry and Molecular Biology, Division of Molecular and Cellular Signaling, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; and Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8514, Japan
| | - Hiroshi Ohnishi
- Department of Biochemistry and Molecular Biology, Division of Molecular and Cellular Signaling, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; and Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8514, Japan
| | - Takashi Matozaki
- Department of Biochemistry and Molecular Biology, Division of Molecular and Cellular Signaling, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; and Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8514, Japan
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30
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Rodriguez PL, Harada T, Christian DA, Pantano DA, Tsai RK, Discher DE. Minimal "Self" peptides that inhibit phagocytic clearance and enhance delivery of nanoparticles. Science 2013; 339:971-5. [PMID: 23430657 PMCID: PMC3966479 DOI: 10.1126/science.1229568] [Citation(s) in RCA: 696] [Impact Index Per Article: 63.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Foreign particles and cells are cleared from the body by phagocytes that must also recognize and avoid clearance of "self" cells. The membrane protein CD47 is reportedly a "marker of self" in mice that impedes phagocytosis of self by signaling through the phagocyte receptor CD172a. Minimal "Self" peptides were computationally designed from human CD47 and then synthesized and attached to virus-size particles for intravenous injection into mice that express a CD172a variant compatible with hCD47. Self peptides delay macrophage-mediated clearance of nanoparticles, which promotes persistent circulation that enhances dye and drug delivery to tumors. Self-peptide affinity for CD172a is near the optimum measured for human CD172a variants, and Self peptide also potently inhibits nanoparticle uptake mediated by the contractile cytoskeleton. The reductionist approach reveals the importance of human Self peptides and their utility in enhancing drug delivery and imaging.
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Affiliation(s)
- Pia L. Rodriguez
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Takamasa Harada
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David A. Christian
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Diego A. Pantano
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Richard K. Tsai
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dennis E. Discher
- Molecular and Cell Biophysics and NanoBioPolymers Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
- Pharmacological Sciences Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA
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31
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CD47: A Cell Surface Glycoprotein Which Regulates Multiple Functions of Hematopoietic Cells in Health and Disease. ISRN HEMATOLOGY 2013; 2013:614619. [PMID: 23401787 PMCID: PMC3564380 DOI: 10.1155/2013/614619] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 11/19/2012] [Indexed: 12/22/2022]
Abstract
Interactions between cells and their surroundings are important for proper function and homeostasis in a multicellular organism. These interactions can either be established between the cells and molecules in their extracellular milieu, but also involve interactions between cells. In all these situations, proteins in the plasma membranes are critically involved to relay information obtained from the exterior of the cell. The cell surface glycoprotein CD47 (integrin-associated protein (IAP)) was first identified as an important regulator of integrin function, but later also was shown to function in ways that do not necessarily involve integrins. Ligation of CD47 can induce intracellular signaling resulting in cell activation or cell death depending on the exact context. By binding to another cell surface glycoprotein, signal regulatory protein alpha (SIRPα), CD47 can regulate the function of cells in the monocyte/macrophage lineage. In this spotlight paper, several functions of CD47 will be reviewed, although some functions may be more briefly mentioned. Focus will be on the ways CD47 regulates hematopoietic cells and functions such as CD47 signaling, induction of apoptosis, and regulation of phagocytosis or cell-cell fusion.
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32
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Soto-Pantoja DR, Miller TW, Pendrak ML, DeGraff WG, Sullivan C, Ridnour LA, Abu-Asab M, Wink DA, Tsokos M, Roberts DD. CD47 deficiency confers cell and tissue radioprotection by activation of autophagy. Autophagy 2012; 8:1628-42. [PMID: 22874555 PMCID: PMC3494592 DOI: 10.4161/auto.21562] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Accidental or therapeutic exposure to ionizing radiation has severe physiological consequences and can result in cell death. We previously demonstrated that deficiency or blockade of the ubiquitously expressed receptor CD47 results in remarkable cell and tissue protection against ischemic and radiation stress. Antagonists of CD47 or its ligand THBS1/thrombospondin 1 enhance cell survival and preserve their proliferative capacity. However the signaling pathways that mediate this cell-autonomous radioprotection are unclear. We now report a marked increase in autophagy in irradiated T-cells and endothelial cells lacking CD47. Irradiated T cells lacking CD47 exhibit significant increases in formation of autophagosomes comprising double-membrane vesicles visualized by electron microscopy and numbers of MAP1LC3A/B(+) puncta. Moreover, we observed significant increases in BECN1, ATG5, ATG7 and a reduction in SQSTM1/p62 expression relative to irradiated wild-type T cells. We observed similar increases in autophagy gene expression in mice resulting from blockade of CD47 in combination with total body radiation. Pharmacological or siRNA-mediated inhibition of autophagy selectively sensitized CD47-deficient cells to radiation, indicating that enhanced autophagy is necessary for the prosurvival response to CD47 blockade. Moreover, re-expression of CD47 in CD47-deficient T cells sensitized these cells to death by ionizing radiation and reversed the increase in autophagic flux associated with survival. This study indicates that CD47 deficiency confers cell survival through the activation of autophagic flux and identifies CD47 blockade as a pharmacological route to modulate autophagy for protecting tissue from radiation injury.
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Affiliation(s)
- David R. Soto-Pantoja
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Thomas W. Miller
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Michael L. Pendrak
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - William G. DeGraff
- Radiation Biology Branch; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Camille Sullivan
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Lisa A. Ridnour
- Radiation Biology Branch; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Mones Abu-Asab
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
- Section of Immunopathology; Laboratory of Immunology; National Eye Institute; National Institutes of Health; Bethesda, MD USA
| | - David A. Wink
- Radiation Biology Branch; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - Maria Tsokos
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
| | - David D. Roberts
- Laboratory of Pathology; Center for Cancer Research; National Cancer Institute; Bethesda, MD USA
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Theocharides APA, Jin L, Cheng PY, Prasolava TK, Malko AV, Ho JM, Poeppl AG, van Rooijen N, Minden MD, Danska JS, Dick JE, Wang JCY. Disruption of SIRPα signaling in macrophages eliminates human acute myeloid leukemia stem cells in xenografts. ACTA ACUST UNITED AC 2012; 209:1883-99. [PMID: 22945919 PMCID: PMC3457732 DOI: 10.1084/jem.20120502] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Inhibition of macrophage SIRPα–CD47 interactions mediates phagocytosis and clearance of acute myeloid leukemia stem cells. Although tumor surveillance by T and B lymphocytes is well studied, the role of innate immune cells, in particular macrophages, is less clear. Moreover, the existence of subclonal genetic and functional diversity in some human cancers such as leukemia underscores the importance of defining tumor surveillance mechanisms that effectively target the disease-sustaining cancer stem cells in addition to bulk cells. In this study, we report that leukemia stem cell function in xenotransplant models of acute myeloid leukemia (AML) depends on SIRPα-mediated inhibition of macrophages through engagement with its ligand CD47. We generated mice expressing SIRPα variants with differential ability to bind human CD47 and demonstrated that macrophage-mediated phagocytosis and clearance of AML stem cells depend on absent SIRPα signaling. We obtained independent confirmation of the genetic restriction observed in our mouse models by using SIRPα-Fc fusion protein to disrupt SIRPα–CD47 engagement. Treatment with SIRPα-Fc enhanced phagocytosis of AML cells by both mouse and human macrophages and impaired leukemic engraftment in mice. Importantly, SIRPα-Fc treatment did not significantly enhance phagocytosis of normal hematopoietic targets. These findings support the development of therapeutics that antagonize SIRPα signaling to enhance macrophage-mediated elimination of AML.
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Affiliation(s)
- Alexandre P A Theocharides
- The Campbell Family Cancer Research Institute, Ontario Cancer Institute, Princess Margaret Hospital, University Health Network, Toronto, Ontario M5G 2M9, Canada
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34
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Van VQ, Baba N, Rubio M, Wakahara K, Panzini B, Richard C, Soucy G, Franchimont D, Fortin G, Torres ACM, Cabon L, Susin S, Sarfati M. CD47(low) status on CD4 effectors is necessary for the contraction/resolution of the immune response in humans and mice. PLoS One 2012; 7:e41972. [PMID: 22870271 PMCID: PMC3411572 DOI: 10.1371/journal.pone.0041972] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 06/29/2012] [Indexed: 12/14/2022] Open
Abstract
How do effector CD4 T cells escape cell death during the contraction of the immune response (IR) remain largely unknown. CD47, through interactions with thrombospondin-1 (TSP-1) and SIRP-α, is implicated in cell death and phagocytosis of malignant cells. Here, we reported a reduction in SIRP-α-Fc binding to effector memory T cells (T(EM)) and in vitro TCR-activated human CD4 T cells that was linked to TSP-1/CD47-induced cell death. The reduced SIRP-α-Fc binding (CD47(low) status) was not detected when CD4 T cells were stained with two anti-CD47 mAbs, which recognize distinct epitopes. In contrast, increased SIRP-α-Fc binding (CD47(high) status) marked central memory T cells (T(CM)) as well as activated CD4 T cells exposed to IL-2, and correlated with resistance to TSP-1/CD47-mediated killing. Auto-aggressive CD4 effectors, which accumulated in lymph nodes and at mucosal sites of patients with Crohn's disease, displayed a CD47(high) status despite a high level of TSP-1 release in colonic tissues. In mice, CD47 (CD47(low) status) was required on antigen (Ag)-specific CD4 effectors for the contraction of the IR in vivo, as significantly lower numbers of Ag-specific CD47(+/+)CD4 T cells were recovered when compared to Ag-specific CD47(-/-) CD4 T cells. In conclusion, we demonstrate that a transient change in the status of CD47, i.e. from CD47(high) to CD47(low), on CD4 effectors regulates the decision-making process that leads to CD47-mediated cell death and contraction of the IR while maintenance of a CD47(high) status on tissue-destructive CD4 effectors prevents the resolution of the inflammatory response.
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Affiliation(s)
- Vu Quang Van
- Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Nobuyasu Baba
- Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Manuel Rubio
- Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Keiko Wakahara
- Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Benoit Panzini
- Department of Gastroenterology, Centre Hospitalier de l’Université de Montréal (CHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Carole Richard
- Department of Digestive Tract Surgery, Centre Hospitalier de l’Université de Montréal (CHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Genevieve Soucy
- Department of Pathology, Centre Hospitalier de l’Université de Montréal (CHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
| | - Denis Franchimont
- Department de Gastroenterology, Erasme Hospital, Université Libre de Bruxelles (ULB), Bruxelles, Belgique
| | - Genevieve Fortin
- Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Ana Carolina Martinez Torres
- INSERM U872, Mort Cellulaire Programmée et Physiopathologie des Cellules Tumorales, Equipe 19, Centre de Recherche des Cordeliers, Paris, France
- Université Pierre et Marie Curie-Sorbonne Universités, UMRS 872, Paris, France
- Université Paris Descartes, Paris, France
| | - Lauriane Cabon
- INSERM U872, Mort Cellulaire Programmée et Physiopathologie des Cellules Tumorales, Equipe 19, Centre de Recherche des Cordeliers, Paris, France
- Université Pierre et Marie Curie-Sorbonne Universités, UMRS 872, Paris, France
- Université Paris Descartes, Paris, France
| | - Santos Susin
- INSERM U872, Mort Cellulaire Programmée et Physiopathologie des Cellules Tumorales, Equipe 19, Centre de Recherche des Cordeliers, Paris, France
- Université Pierre et Marie Curie-Sorbonne Universités, UMRS 872, Paris, France
- Université Paris Descartes, Paris, France
| | - Marika Sarfati
- Immunoregulation Laboratory, Centre Hospitalier de l’Université de Montréal, Research Center (CRCHUM), Notre-Dame Hospital, Montreal, Quebec, Canada
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The effect of CD47 modified polymer surfaces on inflammatory cell attachment and activation. Biomaterials 2011; 32:4317-26. [PMID: 21429575 DOI: 10.1016/j.biomaterials.2011.02.053] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 02/25/2011] [Indexed: 02/04/2023]
Abstract
CD47 is a transmembrane protein that is a marker of "self". CD47 binding to its cognate receptor in leukocytes and macrophages, signal-regulatory protein alpha (SIRPα), causes inhibition of inflammatory cell attachment. We hypothesized that immobilization of recombinant CD47 on polymeric surfaces would reduce inflammation. Recombinant CD47 was appended to polyvinyl chloride (PVC) or polyurethane (PU) surfaces via photoactivation chemistry. Cell culture studies showed that CD47 immobilization significantly reduced human neutrophil (HL-60) and human monocyte derived macrophage (MDM) (THP-1) attachment to PVC and PU respectively. A neutralizing antibody, directed against SIRPα, inhibited THP-1 and HL-60 binding to PU and PVC surfaces respectively. This antibody also increased the level of SIRPα tyrosine phosphorylation, thereby indicating a direct role for SIRPα mediated signaling in preventing inflammatory cell attachment. Studies using human blood in an ex vivo flow-loop showed that CD47 modified PVC tubing significantly reduced cell binding and neutrophil activation compared to unmodified tubing or poly-2-methoxy-ethylacrylate (PMEA) coated tubing. In ten-week rat subdermal implants, CD47 functionalized PU films showed a significant reduction in markers of MDM mediated oxidative degradation compared to unmodified PU. In conclusion, CD47 functionalized surfaces can resist inflammatory cell interactions both in vitro and in vivo.
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Kaur S, Kuznetsova SA, Pendrak ML, Sipes JM, Romeo MJ, Li Z, Zhang L, Roberts DD. Heparan sulfate modification of the transmembrane receptor CD47 is necessary for inhibition of T cell receptor signaling by thrombospondin-1. J Biol Chem 2011; 286:14991-5002. [PMID: 21343308 DOI: 10.1074/jbc.m110.179663] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cell surface proteoglycans on T cells contribute to retroviral infection, binding of chemokines and other proteins, and are necessary for some T cell responses to the matricellular glycoprotein thrombospondin-1. The major cell surface proteoglycans expressed by primary T cells and Jurkat T cells have an apparent M(r) > 200,000 and are modified with chondroitin sulfate and heparan sulfate chains. Thrombospondin-1 bound in a heparin-inhibitable manner to this proteoglycan and to a soluble form released into the medium. Based on mass spectrometry, knockdown, and immunochemical analyses, the proteoglycan contains two major core proteins as follows: amyloid precursor-like protein-2 (APLP2, apparent M(r) 230,000) and CD47 (apparent M(r) > 250,000). CD47 is a known thrombospondin-1 receptor but was not previously reported to be a proteoglycan. This proteoglycan isoform of CD47 is widely expressed on vascular cells. Mutagenesis identified glycosaminoglycan modification of CD47 at Ser(64) and Ser(79). Inhibition of T cell receptor signaling by thrombospondin-1 was lost in CD47-deficient T cells that express the proteoglycan isoform of APLP2, indicating that binding to APLP2 is not sufficient. Inhibition of CD69 induction was restored in CD47-deficient cells by re-expressing CD47 or an S79A mutant but not by the S64A mutant. Therefore, inhibition of T cell receptor signaling by thrombospondin-1 is mediated by CD47 and requires its modification at Ser(64).
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Affiliation(s)
- Sukhbir Kaur
- Laboratory of Pathology, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20982, USA
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Kaur S, Martin-Manso G, Pendrak ML, Garfield SH, Isenberg JS, Roberts DD. Thrombospondin-1 inhibits VEGF receptor-2 signaling by disrupting its association with CD47. J Biol Chem 2010; 285:38923-32. [PMID: 20923780 DOI: 10.1074/jbc.m110.172304] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Thrombospondin-1 (TSP1) can inhibit angiogenic responses directly by interacting with VEGF and indirectly by engaging several endothelial cell TSP1 receptors. We now describe a more potent mechanism by which TSP1 inhibits VEGF receptor-2 (VEGFR2) activation through engaging its receptor CD47. CD47 ligation is known to inhibit downstream signaling targets of VEGFR2, including endothelial nitric-oxide synthase and soluble guanylate cyclase, but direct effects on VEGFR2 have not been examined. Based on FRET and co-immunoprecipitation, CD47 constitutively associated with VEGFR2. Ligation of CD47 by TSP1 abolished resonance energy transfer with VEGFR2 and inhibited phosphorylation of VEGFR2 and its downstream target Akt without inhibiting VEGF binding to VEGFR2. The inhibitory activity of TSP1 in large vessel and microvascular endothelial cells was replicated by a recombinant domain of the protein containing its CD47-binding site and by a CD47-binding peptide derived from this domain but not by the CD36-binding domain of TSP1. Inhibition of VEGFR2 phosphorylation was lost when CD47 expression was suppressed in human endothelial cells and in murine CD47-null cells. These results reveal that anti-angiogenic signaling through CD47 is highly redundant and extends beyond inhibition of nitric oxide signaling to global inhibition of VEGFR2 signaling.
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Affiliation(s)
- Sukhbir Kaur
- Laboratory of Pathology, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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38
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Lee WY, Weber DA, Laur O, Stowell SR, McCall I, Andargachew R, Cummings RD, Parkos CA. The role of cis dimerization of signal regulatory protein alpha (SIRPalpha) in binding to CD47. J Biol Chem 2010; 285:37953-63. [PMID: 20826801 DOI: 10.1074/jbc.m110.180018] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Interaction of SIRPα with its ligand, CD47, regulates leukocyte functions, including transmigration, phagocytosis, oxidative burst, and cytokine secretion. Recent progress has provided significant insights into the structural details of the distal IgV domain (D1) of SIRPα. However, the structural roles of proximal IgC domains (D2 and D3) have been largely unstudied. The high degree of conservation of D2 and D3 among members of the SIRP family as well as the propensity of known IgC domains to assemble in cis has led others to hypothesize that SIRPα forms higher order structures on the cell surface. Here we report that SIRPα forms noncovalently linked cis homodimers. Treatment of SIRPα-expressing cells with a membrane-impermeable cross-linker resulted in the formation of SDS-stable SIRPα dimers and oligomers. Biochemical analyses of soluble recombinant extracellular regions of SIRPα, including domain truncation mutants, revealed that each of the three extracellular immunoglobulin loops of SIRPα formed dimers in solution. Co-immunoprecipitation experiments using cells transfected with different affinity-tagged SIRPα molecules revealed that SIRPα forms cis dimers. Interestingly, in cells treated with tunicamycin, SIRPα dimerization but not CD47 binding was inhibited, suggesting that a SIRPα dimer is probably bivalent. Last, we demonstrate robust dimerization of SIRPa in adherent, stimulated human neutrophils. Collectively, these data are consistent with SIRPα being expressed on the cell surface as a functional cis-linked dimer.
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Affiliation(s)
- Winston Y Lee
- Epithelial Pathobiology Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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39
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Tsai RK, Rodriguez PL, Discher DE. Self inhibition of phagocytosis: the affinity of 'marker of self' CD47 for SIRPalpha dictates potency of inhibition but only at low expression levels. Blood Cells Mol Dis 2010; 45:67-74. [PMID: 20299253 DOI: 10.1016/j.bcmd.2010.02.016] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2010] [Accepted: 01/19/2010] [Indexed: 12/20/2022]
Abstract
Phagocytes engulf foreign cells but not 'self' in part because self cells express CD47 as a ligand for signal regulatory protein SIRPalpha, which inhibits phagocytosis. Motivated by reports of upregulation of CD47 on both normal and cancerous stem cells [1: Jaiswal et al., 2009] and also by polymorphisms in SIRPalpha [2: Takenaka et al., 2007], we show here that inhibition of engulfment correlates with affinity of CD47 for SIRPalpha - but only at low levels of CD47. One common human polymorph of SIRPalpha is studied and binds more strongly to human-CD47 than to mouse-CD47 (K(d) approximately 0.12 microM and 6.9 microM, respectively) and does not bind sheep red blood cells (RBCs) - which are well-established targets of human macrophages; in comparison, a common mouse polymorph of SIRPalpha binds with similar affinity to human and mouse CD47 (K(d) approximately 0.22 microM). Using immunoglobulin (IgG)-opsonized particles with varying levels of either human- or mouse-CD47, the effective inhibition constants K(i) for blocking phagocytosis are then determined with both human- and mouse-derived macrophages. Only human phagocytes show significant differences in man versus mouse K(i)'s and only at CD47 levels below normal densities for RBCs. While phospho-signaling through human-SIRPalpha shows similar trends, consistent again with the affinity differences, saturating levels of CD47 (>K(i)) can signal and inhibit phagocytosis regardless of man versus mouse. Quantitative analyses here prompt more complete characterizations of both CD47 levels and SIRPalpha polymorphisms when attempting to study in vivo effects of these key proteins in innate immunity.
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Affiliation(s)
- Richard K Tsai
- Biophysical Engineering Lab, University of Pennsylvania, Philadelphia, PA 19104, USA.
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41
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White AF, Mazur M, Sorscher EJ, Zinn KR, Ponnazhagan S. Genetic modification of adeno-associated viral vector type 2 capsid enhances gene transfer efficiency in polarized human airway epithelial cells. Hum Gene Ther 2009; 19:1407-14. [PMID: 18778196 DOI: 10.1089/hum.2008.117] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Cystic fibrosis (CF) is a common genetic disease characterized by defects in the expression of the CF transmembrane conductance regulator (CFTR) gene. Gene therapy offers better hope for the treatment of CF. Adeno-associated viral (AAV) vectors are capable of stable expression with low immunogenicity. Despite their potential in CF gene therapy, gene transfer efficiency by AAV is limited because of pathophysiological barriers in these patients. Although a few AAV serotypes have shown better transduction compared with the AAV2-based vectors, gene transfer efficiency in human airway epithelium has still not reached therapeutic levels. To engineer better AAV vectors for enhanced gene delivery in human airway epithelium, we developed and characterized mutant AAV vectors by genetic capsid modification, modeling the well-characterized AAV2 serotype. We genetically incorporated putative high-affinity peptide ligands to human airway epithelium on the GH loop region of AAV2 capsid protein. Six independent mutant AAV were constructed, containing peptide ligands previously reported to bind with high affinity for known and unknown receptors on human airway epithelial cells. The vectors were tested on nonairway cells and nonpolarized and polarized human airway epithelial cells for enhanced infectivity. One of the mutant vectors, with the peptide sequence THALWHT, not only showed the highest transduction in undifferentiated human airway epithelial cells but also indicated significant transduction in polarized cells. Interestingly, this modified vector was also able to infect cells independently of the heparan sulfate proteoglycan receptor. Incorporation of this ligand on other AAV serotypes, which have shown improved gene transfer efficiency in the human airway epithelium, may enhance the application of AAV vectors in CF gene therapy.
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Affiliation(s)
- April F White
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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42
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Estrella C, Rocks N, Paulissen G, Quesada-Calvo F, Noël A, Vilain E, Lassalle P, Tillie-Leblond I, Cataldo D, Gosset P. Role of A disintegrin and metalloprotease-12 in neutrophil recruitment induced by airway epithelium. Am J Respir Cell Mol Biol 2009; 41:449-58. [PMID: 19213876 DOI: 10.1165/rcmb.2008-0124oc] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Among proteases, metalloproteases are implicated in tissue remodeling, as shown in numerous diseases including allergy. ADAMs (A Disintegrin And Metalloprotease) metalloproteases are implicated in physiologic processes such as cytokine and growth factor shedding, cell migration, adhesion, or repulsion. Our aim was to measure ADAM-12 expression in airway epithelium and to define its role during the allergic response. To raise this question, we analyzed the ADAM-12 expression ex vivo after allergen exposure in patients with allergic rhinitis and in vitro in cultured primary human airway epithelial cells (AEC). Clones of BEAS-2B cells transfected with the full-length form of ADAM-12 were generated to study the consequences of ADAM-12 up-regulation on AEC function. After allergen challenge, a strong increase of ADAM-12 expression was observed in airway epithelium from patients with allergic rhinitis but not from control subjects. In contrast with the other HB-epidermal growth factor sheddases, ADAM-10 and -17, TNF-alpha in vitro increased the expression of ADAM-12 by AEC, an effect amplified by IL-4 and IL-13. Up-regulation of ADAM-12 in AEC increased the expression of alpha3 and alpha4 integrins and to the modulation of cell migration on fibronectin but not on collagen. Moreover, overexpression of ADAM-12 in BEAS-2B enhanced the secretion of CXCL1 and CXCL8 and their capacity to recruit neutrophils. CD47 was strongly decreased by ADAM-12 overexpression, a process associated with a reduced adhesion of neutrophils. These effects were mainly dependent on epidermal growth factor receptor activation. In summary, ADAM-12 is produced during allergic reaction by AEC and might increase neutrophil recruitment within airway mucosa.
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Affiliation(s)
- Cecilia Estrella
- INSERM U774, Biomolecules and Pulmonary Inflammation, Institut Pasteur de Lille, 1 rue du Pr Calmette, BP245, 59019 Lille Cedex, France
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Barclay AN. Signal regulatory protein alpha (SIRPalpha)/CD47 interaction and function. Curr Opin Immunol 2009; 21:47-52. [PMID: 19223164 PMCID: PMC3128989 DOI: 10.1016/j.coi.2009.01.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Accepted: 01/20/2009] [Indexed: 12/12/2022]
Abstract
SIRPalpha is an inhibitory receptor present on myeloid cells that interacts with a widely distributed membrane protein CD47. The activating member SIRPbeta, despite extensive sequence similarity to SIRPalpha in the extracellular region, shows negligible binding to CD47. The SIRPalpha/CD47 interaction is unusual in that it can lead to bidirectional signalling through both SIRPalpha and CD47. This review concentrates on the interactions of SIRPalpha with CD47 where recent data have shed light on the structure of the proteins including determining why the activating SIRPbeta does not bind CD47, evidence of extensive polymorphisms and implication for the evolution and function of this protein and paired receptors in general. The interaction may be modified by endocytosis of the receptors, cleavage by proteolysis and through interactions of surfactant proteins.
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Affiliation(s)
- A Neil Barclay
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom.
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Kim Y, Tewari M, Pajerowski JD, Cai S, Sen S, Williams JH, Williams J, Sirsi SR, Sirsi S, Lutz GJ, Lutz G, Discher DE. Polymersome delivery of siRNA and antisense oligonucleotides. J Control Release 2008; 134:132-40. [PMID: 19084037 DOI: 10.1016/j.jconrel.2008.10.020] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Accepted: 10/24/2008] [Indexed: 01/07/2023]
Abstract
siRNA and antisense oligonucleotides, AON, have similar size and negative charge and are often packaged for in vitro delivery with cationic lipids or polymers-but exposed positive charge is problematic in vivo. Here we demonstrate loading and functional delivery of RNAi and AON with non-ionic, nano-transforming polymersomes. These degradable carriers are taken up passively by cultured cells after which the vesicles transform into micelles that allow endolysosomal escape and delivery of either siRNA into cytosol for mRNA knockdown or else AON into the nucleus for exon skipping within pre-mRNA. Polymersome-mediated knockdown appears as efficient as common cationic-lipid transfection and about half as effective as Lenti-virus after sustained selection. For AON, initial results also show that intramuscular injection into a mouse model of muscular dystrophy leads to the expected protein expression, which occurs along the entire length of muscle. The lack of cationic groups in antisense polymersomes together with initial tests of efficacy suggests broader utility of these non-viral carriers.
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Affiliation(s)
- Younghoon Kim
- Department of Chemical and Biomolecular Engineering and Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, USA
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45
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Barros MMO, Yamamoto M, Figueiredo MS, Cançado R, Kimura EYS, Langhi DM, Chiattone CS, Bordin JO. Expression levels of CD47, CD35, CD55, and CD59 on red blood cells and signal-regulatory protein-alpha,beta on monocytes from patients with warm autoimmune hemolytic anemia. Transfusion 2008; 49:154-60. [PMID: 18954403 DOI: 10.1111/j.1537-2995.2008.01936.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Animal models have shown that CD47-deficient mice develop severe autoimmune hemolytic anemia (AIHA) because the binding of red blood cell (RBC) CD47 to signal-regulatory protein (SIRP-alpha) on macrophages contributes to the inhibition of phagocytosis. In contrast, complement-inhibitory proteins such as CD35, CD55, and CD59 may protect RBCs against the lysis by complement. STUDY DESIGN AND METHODS With the use of flow cytometric analyses, the expression of CD47, CD35, CD55, and CD59 on RBCs and of SIRP-alpha,beta on peripheral monocytes of 36 patients with warm AIHA (wAIHA; 23 with active wAIHA, 13 with wAIHA in remission) and 20 healthy subjects was evaluated. RESULTS The mean fluorescence intensities (MFIs) of the expression of CD47, CD35, CD55, and SIRP-alpha,beta of active wAIHA patients, wAIHA in remission, and healthy subjects were not statistically different. Patients with active wAIHA showed significantly lower CD59 expression on RBCs than healthy individuals (MFI, 512.5 +/- 59.6 vs. 553.7 +/- 36.6; p = 0.009), while the CD59 expression in patients with wAIHA in remission was not significantly different from that of healthy controls (MFI, 538.4 +/- 48.3 vs. 553.7 +/- 36.6; p > 0.05). The expression of CD59 on RBCs of 3 patients who died from the wAIHA was lower than that seen on RBCs of healthy controls (MFI, 433.6 +/- 69.6 vs. 553.74 +/- 36.6; p = 0.0001). CONCLUSIONS Our data show that the expression of CD47 on RBCs and SIRP-alpha,beta on monocytes of patients with wAIHA is not different from that seen in healthy individuals. In addition, we detected that patients with active wAIHA present low expression of CD59 and normal expression of CD35 and CD55 on their RBCs. Complement-regulatory proteins may play an important role in protecting RBC destruction through the activation of complement.
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Affiliation(s)
- Melca M O Barros
- Faculdade de Ciências Médicas, Universidade Federal de São Paulo, Santa Casa de São Paulo, São Paulo, Brasil
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Abstract
The ability of phagocytes to discriminate between viable/healthy and apoptotic/foreign/abnormal cells is of fundamental importance; a recent study provides new molecular insights into the function of CD47-SIRP alpha signaling in this discrimination.
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47
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Paired Receptor Specificity Explained by Structures of Signal Regulatory Proteins Alone and Complexed with CD47. Mol Cell 2008; 31:266-77. [DOI: 10.1016/j.molcel.2008.05.026] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 03/13/2008] [Accepted: 05/13/2008] [Indexed: 11/20/2022]
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48
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CD47-Fc fusion proteins as putative immunotherapeutic agents for the treatment of immunological and inflammatory diseases. Expert Opin Ther Pat 2008. [DOI: 10.1517/13543776.18.5.555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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49
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Maile LA, Capps BE, Miller EC, Allen LB, Veluvolu U, Aday AW, Clemmons DR. Glucose regulation of integrin-associated protein cleavage controls the response of vascular smooth muscle cells to insulin-like growth factor-I. Mol Endocrinol 2008; 22:1226-37. [PMID: 18292237 PMCID: PMC2366182 DOI: 10.1210/me.2007-0552] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Accepted: 02/12/2008] [Indexed: 11/19/2022] Open
Abstract
Vascular smooth muscle cells (SMC) maintained in high glucose are more responsive to IGF-I than SMC maintained in normal glucose due to a difference in the Shc phosphorylation response. In this study we aimed to determine the mechanism by which glucose regulates the sensitivity of SMC to IGF-I. For Shc to be phosphorylated in response to IGF-I it must be recruited to tyrosine-phosphorylated sites on Src homology 2 domain-containing phosphatase (SHP) substrate-1 (SHPS-1). The association of integrin-associated protein (IAP) with SHPS-1 is required for SHPS-1 tyrosine phosphorylation. When SMC were grown in 5 mm glucose, the amount of intact IAP was reduced, compared with SMC grown in 25 mm glucose. This reduction was due to proteolytic cleavage of IAP. Proteolysis of IAP resulted in loss of its SHPS-1 binding site, which led to loss of SHPS-1 phosphorylation. Analysis of the conditioned medium showed that there was more protease activity in the medium from SMC cultured in 5 mm glucose as compared with 25 mm. Inhibition of matrix metalloprotease-2 synthesis using RNA interference or its activity using a specific protease inhibitor protected IAP from cleavage. This protection was associated with an increase in IAP-SHPS-1 association, increased recruitment and phosphorylation of Shc, and increased cell growth in response to IGF-I. Our results show that the enhanced response of SMC in 25 mm glucose to IGF-I is due to the protection of IAP from proteolytic degradation, thereby increasing its association with SHPS-1 and allowing the formation of the SHPS-1-Shc signaling complex.
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MESH Headings
- Animals
- CD47 Antigen/metabolism
- Cell Proliferation/drug effects
- Glucose/pharmacology
- Humans
- Insulin-Like Growth Factor I/pharmacology
- Matrix Metalloproteinase 2/genetics
- Matrix Metalloproteinase 2/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Protein Binding/drug effects
- RNA Interference
- Receptors, Immunologic/metabolism
- Signal Transduction/drug effects
- Swine
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Affiliation(s)
- Laura A Maile
- Division of Endocrinology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7170, USA.
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Tsai RK, Discher DE. Inhibition of "self" engulfment through deactivation of myosin-II at the phagocytic synapse between human cells. ACTA ACUST UNITED AC 2008; 180:989-1003. [PMID: 18332220 PMCID: PMC2265407 DOI: 10.1083/jcb.200708043] [Citation(s) in RCA: 344] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phagocytosis of foreign cells or particles by macrophages is a rapid process that is inefficient when faced with “self” cells that display CD47—although signaling mechanisms in self-recognition have remained largely unknown. With human macrophages, we show the phagocytic synapse at cell contacts involves a basal level of actin-driven phagocytosis that, in the absence of species-specific CD47 signaling, is made more efficient by phospho-activated myosin. We use “foreign” sheep red blood cells (RBCs) together with CD47-blocked, antibody-opsonized human RBCs in order to visualize synaptic accumulation of phosphotyrosine, paxillin, F-actin, and the major motor isoform, nonmuscle myosin-IIA. When CD47 is functional, the macrophage counter-receptor and phosphatase-activator SIRPα localizes to the synapse, suppressing accumulation of phosphotyrosine and myosin without affecting F-actin. On both RBCs and microbeads, human CD47 potently inhibits phagocytosis as does direct inhibition of myosin. CD47–SIRPα interaction initiates a dephosphorylation cascade directed in part at phosphotyrosine in myosin. A point mutation turns off this motor's contribution to phagocytosis, suggesting that self-recognition inhibits contractile engulfment.
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Affiliation(s)
- Richard K Tsai
- Biophysical Engineering Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
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