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Elchaninov A, Vishnyakova P, Menyailo E, Sukhikh G, Fatkhudinov T. An Eye on Kupffer Cells: Development, Phenotype and the Macrophage Niche. Int J Mol Sci 2022; 23:ijms23179868. [PMID: 36077265 PMCID: PMC9456487 DOI: 10.3390/ijms23179868] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/14/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Macrophages are key participants in the maintenance of tissue homeostasis under normal and pathological conditions, and implement a rich diversity of functions. The largest population of resident tissue macrophages is found in the liver. Hepatic macrophages, termed Kupffer cells, are involved in the regulation of multiple liver functionalities. Specific differentiation profiles and functional activities of tissue macrophages have been attributed to the shaping role of the so-called tissue niche microenvironments. The fundamental macrophage niche concept was lately shaken by a flood of new data, leading to a revision and substantial update of the concept, which constitutes the main focus of this review. The macrophage community discusses contemporary evidence on the developmental origins of resident macrophages, notably Kupffer cells and the issues of heterogeneity of the hepatic macrophage populations, as well as the roles of proliferation, cell death and migration processes in the maintenance of macrophage populations of the liver. Special consideration is given to interactions of Kupffer cells with other local cell lineages, including Ito cells, sinusoidal endothelium and hepatocytes, which participate in the maintenance of their phenotypical and functional identity.
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Affiliation(s)
- Andrey Elchaninov
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia
- Histology Department, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Correspondence:
| | - Polina Vishnyakova
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia, 117198 Moscow, Russia
| | - Egor Menyailo
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI “Petrovsky National Research Centre of Surgery”, 117418 Moscow, Russia
| | - Gennady Sukhikh
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia
| | - Timur Fatkhudinov
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia, 117198 Moscow, Russia
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI “Petrovsky National Research Centre of Surgery”, 117418 Moscow, Russia
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2
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Zhang Q, Wei Y, Li Y, Jiao X. Low MARCO Expression is Associated with Poor Survival in Patients with Hepatocellular Carcinoma Following Liver Transplantation. Cancer Manag Res 2022; 14:1935-1944. [PMID: 35720642 PMCID: PMC9200231 DOI: 10.2147/cmar.s363219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 05/09/2022] [Indexed: 11/23/2022] Open
Abstract
Background Macrophage receptor with collagenous structure (MARCO) reportedly plays a crucial role in the occurrence and development of several cancers. However, the association between MARCO and the prognosis of hepatocellular carcinoma (HCC) post-liver transplantation remains poorly elucidated. Methods We examined MARCO expression at mRNA and protein level in 145 HCC samples and adjacent nontumor tissues using quantitative reverse transcription PCR, Western blot and immunohistochemistry. Furthermore, we analyzed the correlation of MARCO expression with clinicopathologic features and prognosis. Results We assessed the association between MARCO expression and clinicopathologic features and used the Cox proportional hazards regression model to explore the association between MARCO expression and clinical prognosis of patients with HCC post-liver transplantation. We observed that the expression of MARCO at mRNA and protein level in adjacent nontumor tissues was higher than that in the HCC tissues. Low MARCO expression in HCC tissues was correlated with higher alpha-fetoprotein levels, higher incidence of microvascular invasion, and a higher number of patients beyond Milan criteria. Kaplan–Meier survival curves showed that patients with HCC with low MARCO expression exhibited poor overall survival (OS) and disease-free survival (DFS). Univariate and multivariate analysis revealed that MARCO expression was an independent prognostic factor for OS (hazard ratio [HR] 2.696, 95% confidence interval [CI] 1.335–5.444, P=0.006) and DFS (HR 2.867, 95% CI 1.665–4.936, P<0.001) in patients with HCC post-liver transplantation. Based on immunofluorescence analysis, MARCO expression was primarily localized to macrophages and might be associated with M2-like macrophage polarization during HCC. Conclusion MARCO expression was downregulated in HCC and associated with poor prognosis of patients with HCC post-liver transplantation. Moreover, it could be a potential prognostic marker and therapeutic target in post-liver transplantation HCC.
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Affiliation(s)
- Qi Zhang
- Organ Transplant Center, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Yuxuan Wei
- Organ Transplant Center, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Yihu Li
- Organ Transplant Center, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
| | - Xingyuan Jiao
- Organ Transplant Center, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, People's Republic of China
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3
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Boada CA, Zinger A, Rohen S, Martinez JO, Evangelopoulos M, Molinaro R, Lu M, Villarreal-Leal RA, Giordano F, Sushnitha M, De Rosa E, Simonsen JB, Shevkoplyas S, Taraballi F, Tasciotti E. LDL-Based Lipid Nanoparticle Derived for Blood Plasma Accumulates Preferentially in Atherosclerotic Plaque. Front Bioeng Biotechnol 2021; 9:794676. [PMID: 34926432 PMCID: PMC8672093 DOI: 10.3389/fbioe.2021.794676] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 11/10/2021] [Indexed: 11/24/2022] Open
Abstract
Apolipoprotein-based drug delivery is a promising approach to develop safe nanoparticles capable of targeted drug delivery for various diseases. In this work, we have synthesized a lipid-based nanoparticle (NPs) that we have called “Aposomes” presenting native apolipoprotein B-100 (apoB-100), the primary protein present in Low-Density Lipoproteins (LDL) on its surface. The aposomes were synthesized from LDL isolated from blood plasma using a microfluidic approach. The synthesized aposomes had a diameter of 91 ± 4 nm and a neutral surface charge of 0.7 mV ± mV. Protein analysis using western blot and flow cytometry confirmed the presence of apoB-100 on the nanoparticle’s surface. Furthermore, Aposomes retained liposomes’ drug loading capabilities, demonstrating a prolonged release curve with ∼80% cargo release at 4 hours. Considering the natural tropism of LDL towards the atherosclerotic plaques, we evaluated the biological properties of aposomes in a mouse model of advanced atherosclerosis. We observed a ∼20-fold increase in targeting of plaques when comparing aposomes to control liposomes. Additionally, aposomes presented a favorable biocompatibility profile that showed no deviation from typical values in liver toxicity markers (i.e., LDH, ALT, AST, Cholesterol). The results of this study demonstrate the possibilities of using apolipoprotein-based approaches to create nanoparticles with active targeting capabilities and could be the basis for future cardiovascular therapies.
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Affiliation(s)
- Christian A Boada
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States.,Tecnológico de Monterrey, Escuela de Ingeniería y Ciencias, México, Mexico
| | - Assaf Zinger
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States.,Department of Engineering Medicine, Texas A&M University, Houston, TX, United States.,Laboratory for Bioinspired NanoEngineering and Translational Therapeutics, Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Scott Rohen
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States
| | - Jonathan O Martinez
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States
| | - Michael Evangelopoulos
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States
| | - Roberto Molinaro
- IRCCS Ospedale San Raffaele srl, Milan, Italy.,Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Madeleine Lu
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Ramiro Alejandro Villarreal-Leal
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States.,Tecnológico de Monterrey, Escuela de Ingeniería y Ciencias, México, Mexico
| | - Federica Giordano
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States.,Department of Orthopedics and Sports Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Manuela Sushnitha
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States
| | - Enrica De Rosa
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States
| | - Jens B Simonsen
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Sergey Shevkoplyas
- Department of Biomedical Engineering, University of Houston, Houston, TX, United States
| | - Francesca Taraballi
- Regenerative Medicine Program, Houston Methodist Research Institute, Houston, TX, United States.,Department of Orthopedics and Sports Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Ennio Tasciotti
- San Raffaele University, Rome and IRCCS San Raffaele Hospital, Rome, Italy
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4
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Elchaninov A, Lokhonina A, Vishnyakova P, Soboleva A, Poltavets A, Artemova D, Makarov A, Glinkina V, Goldshtein D, Bolshakova G, Sukhikh G, Fatkhudinov T. MARCO + Macrophage Dynamics in Regenerating Liver after 70% Liver Resection in Mice. Biomedicines 2021; 9:biomedicines9091129. [PMID: 34572315 PMCID: PMC8471044 DOI: 10.3390/biomedicines9091129] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 08/25/2021] [Accepted: 08/28/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Macrophages play a key role in liver regeneration. The fates of resident macrophages after 70% resection are poorly investigated. In this work, using the MARCO macrophage marker (abbreviated from macrophage receptor with collagenous structure), we studied the dynamics of mouse liver resident macrophages after 70% resection. METHODS In BALB/c male mice, a model of liver regeneration after 70% resection was reproduced. The dynamics of markers CD68, TIM4, and MARCO were studied immunohistochemically and by using a Western blot. RESULTS The number of MARCO- and CD68-positive macrophages in the regenerating liver increased 1 day and 3 days after resection, respectively. At the same time, the content of the MARCO protein increased in the sorted macrophages of the regenerating liver on the third day. CONCLUSIONS The data indicate that the number of MARCO-positive macrophages in the regenerating liver increases due to the activation of MARCO synthesis in the liver macrophages. The increased expression of MARCO by macrophages can be regarded as a sign of their activation. In the present study, stimulation with LPS led to an increase in the expression of the Marco gene in both Kupffer cells and macrophages of bone marrow origin.
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Affiliation(s)
- Andrey Elchaninov
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia; (A.L.); (P.V.); (A.P.); (G.S.)
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (A.M.); (T.F.)
- Correspondence:
| | - Anastasia Lokhonina
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia; (A.L.); (P.V.); (A.P.); (G.S.)
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (A.M.); (T.F.)
| | - Polina Vishnyakova
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia; (A.L.); (P.V.); (A.P.); (G.S.)
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (A.M.); (T.F.)
| | - Anna Soboleva
- Laboratory of Growth and Development, Scientific Research Institute of Human Morphology, 117418 Moscow, Russia; (A.S.); (D.A.); (G.B.)
| | - Anastasiya Poltavets
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia; (A.L.); (P.V.); (A.P.); (G.S.)
| | - Daria Artemova
- Laboratory of Growth and Development, Scientific Research Institute of Human Morphology, 117418 Moscow, Russia; (A.S.); (D.A.); (G.B.)
| | - Andrey Makarov
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (A.M.); (T.F.)
| | - Valeria Glinkina
- Histology Department, Pirogov Russian National Research Medical University, Ministry of Healthcare of the Russian Federation, 117997 Moscow, Russia;
| | - Dmitry Goldshtein
- Stem Cell Genetics Laboratory, Research Centre for Medical Genetics, 115522 Moscow, Russia;
| | - Galina Bolshakova
- Laboratory of Growth and Development, Scientific Research Institute of Human Morphology, 117418 Moscow, Russia; (A.S.); (D.A.); (G.B.)
| | - Gennady Sukhikh
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 117997 Moscow, Russia; (A.L.); (P.V.); (A.P.); (G.S.)
| | - Timur Fatkhudinov
- Histology Department, Medical Institute, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (A.M.); (T.F.)
- Laboratory of Growth and Development, Scientific Research Institute of Human Morphology, 117418 Moscow, Russia; (A.S.); (D.A.); (G.B.)
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La Fleur L, Boura VF, Alexeyenko A, Berglund A, Pontén V, Mattsson JSM, Djureinovic D, Persson J, Brunnström H, Isaksson J, Brandén E, Koyi H, Micke P, Karlsson MCI, Botling J. Expression of scavenger receptor MARCO defines a targetable tumor-associated macrophage subset in non-small cell lung cancer. Int J Cancer 2018; 143:1741-1752. [PMID: 29667169 DOI: 10.1002/ijc.31545] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 03/14/2018] [Accepted: 03/28/2018] [Indexed: 12/14/2022]
Abstract
Tumor-associated macrophages (TAMs) are attractive targets for immunotherapy. Recently, studies in animal models showed that treatment with an anti-TAM antibody directed against the scavenger receptor MARCO resulted in suppression of tumor growth and metastatic dissemination. Here we investigated the expression of MARCO in relation to other macrophage markers and immune pathways in a non-small cell lung cancer (NSCLC) cohort (n = 352). MARCO, CD68, CD163, MSR1 and programmed death ligand-1 (PD-L1) were analyzed by immunohistochemistry and immunofluorescence, and associations to other immune cells and regulatory pathways were studied in a subset of cases (n = 199) with available RNA-seq data. We observed a large variation in macrophage density between cases and a strong correlation between CD68 and CD163, suggesting that the majority of TAMs present in NSCLC exhibit a protumor phenotype. Correlation to clinical data only showed a weak trend toward worse survival for patients with high macrophage infiltration. Interestingly, MARCO was expressed on a distinct subpopulation of TAMs, which tended to aggregate in close proximity to tumor cell nests. On the transcriptomic level, we found a positive association between MARCO gene expression and general immune response pathways including strong links to immunosuppressive TAMs, T-cell infiltration and immune checkpoint molecules. Indeed, a higher macrophage infiltration was seen in tumors expressing PD-L1, and macrophages residing within tumor cell nests co-expressed MARCO and PD-L1. Thus, MARCO is a potential new immune target for anti-TAM treatment in a subset of NSCLC patients, possibly in combination with available immune checkpoint inhibitors.
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Affiliation(s)
- Linnéa La Fleur
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Vanessa F Boura
- Department of Microbiology, Tumor and Cell biology, Karolinska institutet, Stockholm, Sweden
| | - Andrey Alexeyenko
- Department of Microbiology, Tumor and Cell biology, Karolinska institutet, Stockholm, Sweden.,Science for Life Laboratory, National Bioinformatics Infrastructure Sweden, Solna, Sweden
| | | | - Victor Pontén
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Johanna S M Mattsson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Dijana Djureinovic
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Johan Persson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Hans Brunnström
- Division of Pathology, Lund University, Skåne University Hospital, Lund, Sweden
| | - Johan Isaksson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden.,Department of Respiratory Medicine, Gävle Hospital, Gävle, Sweden.,County Council of Gävleborg, Centre for Research and Development, Uppsala University, Uppsala, Sweden
| | - Eva Brandén
- Department of Respiratory Medicine, Gävle Hospital, Gävle, Sweden.,County Council of Gävleborg, Centre for Research and Development, Uppsala University, Uppsala, Sweden
| | - Hirsh Koyi
- Department of Respiratory Medicine, Gävle Hospital, Gävle, Sweden.,County Council of Gävleborg, Centre for Research and Development, Uppsala University, Uppsala, Sweden
| | - Patrick Micke
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
| | - Mikael C I Karlsson
- Department of Microbiology, Tumor and Cell biology, Karolinska institutet, Stockholm, Sweden
| | - Johan Botling
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
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6
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Stichling N, Suomalainen M, Flatt JW, Schmid M, Pacesa M, Hemmi S, Jungraithmayr W, Maler MD, Freudenberg MA, Plückthun A, May T, Köster M, Fejer G, Greber UF. Lung macrophage scavenger receptor SR-A6 (MARCO) is an adenovirus type-specific virus entry receptor. PLoS Pathog 2018. [PMID: 29522575 PMCID: PMC5862501 DOI: 10.1371/journal.ppat.1006914] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Macrophages are a diverse group of phagocytic cells acting in host protection against stress, injury, and pathogens. Here, we show that the scavenger receptor SR-A6 is an entry receptor for human adenoviruses in murine alveolar macrophage-like MPI cells, and important for production of type I interferon. Scavenger receptors contribute to the clearance of endogenous proteins, lipoproteins and pathogens. Knockout of SR-A6 in MPI cells, anti-SR-A6 antibody or the soluble extracellular SR-A6 domain reduced adenovirus type-C5 (HAdV-C5) binding and transduction. Expression of murine SR-A6, and to a lower extent human SR-A6 boosted virion binding to human cells and transduction. Virion clustering by soluble SR-A6 and proximity localization with SR-A6 on MPI cells suggested direct adenovirus interaction with SR-A6. Deletion of the negatively charged hypervariable region 1 (HVR1) of hexon reduced HAdV-C5 binding and transduction, implying that the viral ligand for SR-A6 is hexon. SR-A6 facilitated macrophage entry of HAdV-B35 and HAdV-D26, two important vectors for transduction of hematopoietic cells and human vaccination. The study highlights the importance of scavenger receptors in innate immunity against human viruses. Macrophages are a diverse group of phagocytic cells acting in host protection against stress, injury, and pathogens. They phenotypically and functionally adapt to their local environment, for example, peritoneal macrophages are distinct from brain-resident microglia, from liver-resident Kupffer cells or lung macrophages in the lung. Airway macrophages are among the first cells to encounter human respiratory viruses, such as adenoviruses. They release pro-inflammatory cytokines, kill pathogens, present antigens, and restore tissues. Yet, interactions of viruses with lung macrophages are poorly understood, and it is unclear, how they lead to infection or virus clearance. Here we identified the murine scavenger receptor SR-A6 as a receptor for a subset of human adenoviruses on alveolar macrophage-like cells, so-called MPI cells. Scavenger receptors comprise a large family of trans-membrane proteins, and contribute to the clearance of endogenous proteins, lipoproteins and pathogens. In a series of robust experimentation, we show that adenoviruses use SR-A6 as an entry receptor for infection of MPI cells, and production of type I interferon. MPI cells are non-transformed, self-renewing macrophages derived from fetal murine liver, and closely resemble adult alveolar macrophages. The results demonstrate that SR-A6 binds virions on the surface of alveolar macrophage-like cells, and leads to infection.
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MESH Headings
- Adenoviridae Infections/immunology
- Adenoviridae Infections/metabolism
- Adenoviridae Infections/virology
- Adenoviruses, Human/immunology
- Animals
- Humans
- Immunity, Innate
- Lung/immunology
- Lung/metabolism
- Lung/virology
- Macrophages/immunology
- Macrophages/metabolism
- Macrophages/virology
- Macrophages, Alveolar/immunology
- Macrophages, Alveolar/metabolism
- Macrophages, Alveolar/virology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Protein Binding
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- Receptors, Immunologic/physiology
- Virus Internalization
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Affiliation(s)
- Nicole Stichling
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- Molecular Life Sciences Graduate School, ETH and University of Zurich, Switzerland
| | - Maarit Suomalainen
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Justin W. Flatt
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Markus Schmid
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Martin Pacesa
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Silvio Hemmi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Wolfgang Jungraithmayr
- University Hospital Zurich, Institute of Thorax Surgery, Zurich, Switzerland
- present address: Department of Thoracic Surgery, Medical University Brandenburg, Neuruppin, Germany
| | - Mareike D. Maler
- Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
- Allergy Research Group, Department of Dermatology, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Marina A. Freudenberg
- Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, Albert-Ludwigs-Universität, Freiburg, Germany
- Department of Pneumology, Medical Center–University of Freiburg and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Tobias May
- Inscreenex GmbH, Inhoffenstr. Brunswick, Germany
| | - Mario Köster
- Helmholtz-Zentrum für Infektionsforschung GmbH, Braunschweig, Germany
| | - György Fejer
- School of Biomedical and Healthcare Sciences, Peninsula Schools of Medicine and Dentistry, University of Plymouth, Plymouth, United Kingdom
| | - Urs F. Greber
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- * E-mail:
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7
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Zani IA, Stephen SL, Mughal NA, Russell D, Homer-Vanniasinkam S, Wheatcroft SB, Ponnambalam S. Scavenger receptor structure and function in health and disease. Cells 2015; 4:178-201. [PMID: 26010753 PMCID: PMC4493455 DOI: 10.3390/cells4020178] [Citation(s) in RCA: 226] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 05/14/2015] [Accepted: 05/15/2015] [Indexed: 12/23/2022] Open
Abstract
Scavenger receptors (SRs) are a ‘superfamily’ of membrane-bound receptors that were initially thought to bind and internalize modified low-density lipoprotein (LDL), though it is currently known to bind to a variety of ligands including endogenous proteins and pathogens. New family of SRs and their properties have been identified in recent years, and have now been classified into 10 eukaryote families, defined as Classes A-J. These receptors are classified according to their sequences, although in each class they are further classified based in the variations of the sequence. Their ability to bind a range of ligands is reflected on the biological functions such as clearance of modified lipoproteins and pathogens. SR members regulate pathophysiological states including atherosclerosis, pathogen infections, immune surveillance, and cancer. Here, we review our current understanding of SR structure and function implicated in health and disease.
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Affiliation(s)
- Izma Abdul Zani
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Sam L Stephen
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Nadeem A Mughal
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
- Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX, UK
| | - David Russell
- Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX, UK
| | | | - Stephen B Wheatcroft
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK
| | - Sreenivasan Ponnambalam
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK.
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8
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Kelley JL, Ozment TR, Li C, Schweitzer JB, Williams DL. Scavenger receptor-A (CD204): a two-edged sword in health and disease. Crit Rev Immunol 2015; 34:241-61. [PMID: 24941076 DOI: 10.1615/critrevimmunol.2014010267] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Scavenger receptor A (SR-A), also known as the macrophage scavenger receptor and cluster of differentiation 204 (CD204), plays roles in lipid metabolism, atherogenesis, and a number of metabolic processes. However, recent evidence points to important roles for SR-A in inflammation, innate immunity, host defense, sepsis, and ischemic injury. Herein, we review the role of SR-A in inflammation, innate immunity, host defense, sepsis, cardiac and cerebral ischemic injury, Alzheimer's disease, virus recognition and uptake, bone metabolism, and pulmonary injury. Interestingly, SR-A is reported to be host protective in some disease states, but there is also compelling evidence that SR-A plays a role in the pathophysiology of other diseases. These observations of both harmful and beneficial effects of SR-A are discussed here in the framework of inflammation, innate immunity, and endoplasmic reticulum stress.
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Affiliation(s)
- Jim L Kelley
- Departments of Internal Medicine, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614
| | - Tammy R Ozment
- Departments of Surgery, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614
| | - Chuanfu Li
- Departments of Surgery, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614
| | - John B Schweitzer
- Departments of Pathology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614
| | - David L Williams
- Departments of Surgery, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614
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9
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Stephen SL, Freestone K, Dunn S, Twigg MW, Homer-Vanniasinkam S, Walker JH, Wheatcroft SB, Ponnambalam S. Scavenger receptors and their potential as therapeutic targets in the treatment of cardiovascular disease. Int J Hypertens 2010; 2010:646929. [PMID: 20981357 PMCID: PMC2958427 DOI: 10.4061/2010/646929] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Accepted: 07/07/2010] [Indexed: 12/12/2022] Open
Abstract
Scavenger receptors act as membrane-bound and soluble proteins that bind to macromolecular complexes and pathogens. This diverse supergroup of proteins mediates binding to modified lipoprotein particles which regulate the initiation and progression of atherosclerotic plaques. In vascular tissues, scavenger receptors are implicated in regulating intracellular signaling, lipid accumulation, foam cell development, and cellular apoptosis or necrosis linked to the pathophysiology of atherosclerosis. One approach is using gene therapy to modulate scavenger receptor function in atherosclerosis. Ectopic expression of membrane-bound scavenger receptors using viral vectors can modify lipid profiles and reduce the incidence of atherosclerosis. Alternatively, expression of soluble scavenger receptors can also block plaque initiation and progression. Inhibition of scavenger receptor expression using a combined gene therapy and RNA interference strategy also holds promise for long-term therapy. Here we review our current understanding of the gene delivery by viral vectors to cells and tissues in gene therapy strategies and its application to the modulation of scavenger receptor function in atherosclerosis.
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Affiliation(s)
- Sam L Stephen
- Endothelial Cell Biology Unit, Institute of Molecular & Cellular Biology, LIGHT Laboratories, University of Leeds, Clarendon Way, Leeds LS2 9JT, UK
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10
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MARCO, a macrophage scavenger receptor highly expressed in rodents, mediates dalcetrapib-induced uptake of lipids by rat and mouse macrophages. Toxicol In Vitro 2010; 24:745-50. [DOI: 10.1016/j.tiv.2010.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 01/04/2010] [Accepted: 01/08/2010] [Indexed: 11/22/2022]
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11
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DeWitte-Orr SJ, Collins SE, Bauer CMT, Bowdish DM, Mossman KL. An accessory to the 'Trinity': SR-As are essential pathogen sensors of extracellular dsRNA, mediating entry and leading to subsequent type I IFN responses. PLoS Pathog 2010; 6:e1000829. [PMID: 20360967 PMCID: PMC2847946 DOI: 10.1371/journal.ppat.1000829] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Accepted: 02/22/2010] [Indexed: 12/24/2022] Open
Abstract
Extracellular RNA is becoming increasingly recognized as a signaling molecule. Virally derived double stranded (ds)RNA released into the extracellular space during virus induced cell lysis acts as a powerful inducer of classical type I interferon (IFN) responses; however, the receptor that mediates this response has not been identified. Class A scavenger receptors (SR-As) are likely candidates due to their cell surface expression and ability to bind nucleic acids. In this study, we investigated a possible role for SR-As in mediating type I IFN responses induced by extracellular dsRNA in fibroblasts, a predominant producer of IFNbeta. Fibroblasts were found to express functional SR-As, even SR-A species thought to be macrophage specific. SR-A specific competitive ligands significantly blocked extracellular dsRNA binding, entry and subsequent interferon stimulated gene (ISG) induction. Candidate SR-As were systematically investigated using RNAi and the most dramatic inhibition in responses was observed when all candidate SR-As were knocked down in unison. Partial inhibition of dsRNA induced antiviral responses was observed in vivo in SR-AI/II(-/-) mice compared with WT controls. The role of SR-As in mediating extracellular dsRNA entry and subsequent induced antiviral responses was observed in both murine and human fibroblasts. SR-As appear to function as 'carriers', facilitating dsRNA entry and delivery to the established dsRNA sensing receptors, specifically TLR3, RIGI and MDA-5. Identifying SR-As as gatekeepers of the cell, mediating innate antiviral responses, represents a novel function for this receptor family and provides insight into how cells recognize danger signals associated with lytic virus infections. Furthermore, the implications of a cell surface receptor capable of recognizing extracellular RNA may exceed beyond viral immunity to mediating other important innate immune functions.
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Affiliation(s)
| | - Susan E. Collins
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Carla M. T. Bauer
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Dawn M. Bowdish
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Karen L. Mossman
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
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12
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Haywood MEK, Rose SJ, Horswell S, Lees MJ, Fu G, Walport MJ, Morley BJ. Overlapping BXSB congenic intervals, in combination with microarray gene expression, reveal novel lupus candidate genes. Genes Immun 2007; 7:250-63. [PMID: 16541099 DOI: 10.1038/sj.gene.6364294] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The BXSB mouse strain is an important model of glomerulonephritis observed in systemic lupus erythematosus (SLE). Linkage studies have successfully identified disease-susceptibility intervals; however, extracting the identity of the susceptibility gene(s) in such regions is the crucial next step. Congenic mouse strains present a defined genetic resource that is highly amenable to microarray analysis. We have performed microarray analysis using a series of chromosome 1 BXSB congenic mice with partially overlapping disease-susceptibility intervals. Simultaneous comparison of the four congenic lines allowed the identification of expression differences associated with both the initiation and progression of disease. Thus, we have identified a number of novel SLE disease gene candidates and have confirmed the identity of Ifi202 as a disease candidate in the BXSB strain. Sequencing of the promoter regions of Gas5 has revealed polymorphisms in the BXSB strain, which may account for the differential expression profile. Furthermore, the combination of the microarray results with the different phenotypes of these mice has allowed the identification of a number of expression differences that do not necessarily map to the congenic interval, but may be implicated in disease pathways.
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Affiliation(s)
- M E K Haywood
- Rheumatology Section, Division of Medicine, Imperial College Faculty of Medicine, London, UK
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13
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Sarraj MA, McClive PJ, Wilmore HP, Loveland KL, Sinclair AH. Novel scavenger receptor gene is differentially expressed in the embryonic and adult mouse testis. Dev Dyn 2006; 234:1026-33. [PMID: 16245330 DOI: 10.1002/dvdy.20594] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
In an effort to understand the mechanisms that underpin gonadal differentiation at the time of sex determination, we identified a cDNA encoding a putative novel testis expressed scavenger receptor, Tesr. Based on its domain structure, we hypothesize that the function of Tesr is similar to that of other scavenger receptors that play roles in phagocytosis of apoptotic cells, cell-cell adhesion, and defense. Tesr mRNA was detected in fetal mouse gonads of both sexes at 11.5 days post coitum (dpc). From 12.0 dpc, Tesr expression rapidly decreased in the female and was maintained in the male. Expression was seen in embryonic mouse sites other than the testis, such as in brain, eye, head, heart, neural arch, and cartilage primordium. Tesr expression in the newborn testis was faint to undetectable, but it increased from 2 days postpartum (dpp) until 15 dpp and was found in a subset of interstitial cells and in germ and Sertoli cells. Tesr mRNA in the adult mouse testis was observed in Sertoli cells, spermatogonia, spermatocytes, round spermatids, and in a subset of interstitial cells. We conclude that Tesr is differentially expressed in the male vs. female embryonic gonad and is expressed in both the ovary and the testes postnatally after 2 dpp.
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Affiliation(s)
- M A Sarraj
- The ARC Centre of Excellence in Biotechnology and Development, Melbourne, VIC, Australia.
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14
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Frigola J, Song J, Stirzaker C, Hinshelwood RA, Peinado MA, Clark SJ. Epigenetic remodeling in colorectal cancer results in coordinate gene suppression across an entire chromosome band. Nat Genet 2006; 38:540-9. [PMID: 16642018 DOI: 10.1038/ng1781] [Citation(s) in RCA: 286] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Accepted: 03/16/2006] [Indexed: 12/22/2022]
Abstract
We report a new mechanism in carcinogenesis involving coordinate long-range epigenetic gene silencing. Epigenetic silencing in cancer has always been envisaged as a local event silencing discrete genes. However, in this study of silencing in colorectal cancer, we found common repression of the entire 4-Mb band of chromosome 2q.14.2, associated with global methylation of histone H3 Lys9. DNA hypermethylation within the repressed genomic neighborhood was localized to three separate enriched CpG island 'suburbs', with the largest hypermethylated suburb spanning 1 Mb. These data change our understanding of epigenetic gene silencing in cancer cells: namely, epigenetic silencing can span large regions of the chromosome, and both DNA-methylated and neighboring unmethylated genes can be coordinately suppressed by global changes in histone modification. We propose that loss of gene expression can occur through long-range epigenetic silencing, with similar implications as loss of heterozygosity in cancer.
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Affiliation(s)
- Jordi Frigola
- Cancer Program, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney 2010, New South Wales, Australia
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15
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Murphy JE, Tedbury PR, Homer-Vanniasinkam S, Walker JH, Ponnambalam S. Biochemistry and cell biology of mammalian scavenger receptors. Atherosclerosis 2006; 182:1-15. [PMID: 15904923 DOI: 10.1016/j.atherosclerosis.2005.03.036] [Citation(s) in RCA: 247] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Revised: 03/10/2005] [Accepted: 03/24/2005] [Indexed: 01/14/2023]
Abstract
Scavenger receptors are integral membrane proteins that bind a wide variety of ligands including modified or oxidised low-density lipoproteins, apoptotic cells and pathogens. Modified low-density lipoprotein accumulation is thought to be an early event in vascular disease and thus scavenger receptor function is critical in this context. The scavenger receptor family has at least eight different subclasses (A-H) which bear little sequence homology to each other but recognize common ligands. Here we review our current understanding of the scavenger receptor subclasses with emphasis on their genetics, protein structure, biochemical properties, membrane trafficking, intracellular signalling and links to disease states. We also highlight emerging areas where scavenger receptors play roles in cell and animal physiology.
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Affiliation(s)
- Jane E Murphy
- School of Biochemistry and Microbiology, University of Leeds, Leeds LS2 9JT, UK
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16
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Grolleau A, Misek DE, Kuick R, Hanash S, Mulé JJ. Inducible expression of macrophage receptor Marco by dendritic cells following phagocytic uptake of dead cells uncovered by oligonucleotide arrays. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 171:2879-88. [PMID: 12960310 DOI: 10.4049/jimmunol.171.6.2879] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The efficient Ag presenting and immunostimulatory capacity of dendritic cells (DCs) has led to the use of tumor Ag-pulsed DCs in treatment regimens for cancer. Although vaccine studies involving tumor lysate-pulsed DCs have been performed, little, if any, information is available on the effects of phagocytic uptake of tumor lysate on DC biology and function. We have investigated gene expression pattern differences between unpulsed DCs and tumor lysate-pulsed-DCs, using Affymetrix MG-U74Av2 oligonucleotide arrays, which contain approximately 12,000 genes and expressed sequence tags. Upon 24 h tumor lysate pulsing, the levels of 87 transcripts increased at least 3-fold while the levels of 121 transcripts were reduced by one-third or more, with accompanying p values <0.01. Most of these genes encoded proteins important for DC effector functions including cytokines, chemokines, and receptors, such as IL-12p40, macrophage inflammatory protein-2, and IL-6; Ag presentation, such as carboxypeptidase D and H2-DM; cell adhesion (e.g., EGF-like module containing, mucin-like, hormone receptor-like sequence 1, rhoB); and T cell activation. Interestingly, we observed a high level of expression of a novel member of the class A scavenger receptor family, macrophage receptor with collagenous structure (Marco). Marco is thought to play an important role in the immune response by mediating binding and phagocytosis, but also in the formation of lamellipodia-like structures and of dendritic processes. Therefore, we have identified a repertoire of genes that likely play a role in DC function.
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Affiliation(s)
- Annabelle Grolleau
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
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17
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Finger AN, Bisoffi M, Wetterwald A, Gautschi E, Hohenfeld U, Klima I, Stadler BM, Mazzucchelli L, Thalmann GN, Cecchini MG. Scavenger receptor block as strategy for the identification of bone marrow homing phages by panning in vivo random peptide phage displayed libraries. J Immunol Methods 2002; 264:173-86. [PMID: 12191520 DOI: 10.1016/s0022-1759(02)00089-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Surface molecules exclusively expressed by cells of the bone marrow (BM) are candidate targets for delivering therapeutic agents to this tissue. To identify ligands specific for the BM, we performed a series of pannings in vivo with random peptide phage displayed libraries (RPPDL). We could show that phages bind to bone marrow endothelium (BME) independently of the peptide insert, suggesting that the BM, similarly to spleen and liver, is part of the reticulo-endothelial system (RES). Furthermore, this strong "natural" affinity to the BME was abrogated by polyanions, indicating that phage trapping by this endothelium is mediated by scavenger receptors (SR). To circumvent interference by SR, polyinosinic acid was administered before phage panning in vivo. This led to the identification of a consensus motif that confers binding specificity for a subpopulation of hemopoietic marrow cells. Thus, SR inhibition, by avoiding phage trapping by the endothelium, seems to allow phage particles to extravasate and reach parenchymal cells. Accordingly, this panning strategy in vivo may be useful for the identification of targeting motifs specific for cells located in the extravascular space of various tissues.
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Affiliation(s)
- Anita N Finger
- Gene Therapy Laboratory, Department of Clinical Research and Department of Urology, University of Bern, Sahli-Haus 2, Inselspital, Bern, Switzerland
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18
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Shakhov AN, Nedospasov SA. Expression profiling in knockout mice: lymphotoxin versus tumor necrosis factor in the maintenance of splenic microarchitecture. Cytokine Growth Factor Rev 2001; 12:107-19. [PMID: 11312122 DOI: 10.1016/s1359-6101(01)00004-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Expression profiling provides a powerful approach to define the underlying molecular mechanisms in disease. Several techniques referred collectively to as gene profiling may be also helpful in the analysis of the phenotype of mice with targeted mutations, especially if applied to distinct histological compartments, to specific cell types or to evaluate the effect of specific challenges, such as infection. Here we review several of the existing techniques applicable to genetic knockout studies, and share our experience from the study of mice with tumor necrosis factor (TNF) and lymphotoxin (LT) deficiencies, with specific emphasis on the distinction between TNF- and LT-mediated signalling pathways in vivo. Gene expression profiling analysis of TNF/LT-deficient mice supports the notion that TNF and LT, originally discovered as distinct biological activities, manifest both distinct and redundant functions in vivo.
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Affiliation(s)
- A N Shakhov
- Intramural Research Support Program, SAIC Frederick, Division of Basic Sciences, Building 560, Room 31-33, NCI-FCRDC, PO Box B, Frederick, MD 21702, USA.
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19
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Abstract
MARCO (macrophage receptor with collagenous structure) belongs to the class A scavenger receptor molecules. The structure and function of the molecule is described. Although it is expressed on subsets of macrophages, it can be upregulated on other macrophages after bacterial infection. The strategic position of MARCO-expressing cells in lymphoid organs suggests an important role for this bacteria-binding molecule in removal of pathogens.
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Affiliation(s)
- G Kraal
- Department of Cell Biology and Immunology, Vrije Universiteit Amsterdam, van der Boechorststraat 7, 1081 BT, Amsterdam, the Netherlands
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