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Chembukavu SN, Lindsay AJ. Therapy-induced senescence in breast cancer: an overview. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2024; 5:902-920. [PMID: 39280248 PMCID: PMC11390292 DOI: 10.37349/etat.2024.00254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 06/06/2024] [Indexed: 09/18/2024] Open
Abstract
Outcomes for women with breast cancer have improved dramatically in recent decades. However, many patients present with intrinsic drug resistance and others are initially sensitive to anti-cancer drugs but acquire resistance during the course of their treatment, leading to recurrence and/or metastasis. Drug therapy-induced senescence (TIS) is a form of drug resistance characterised by the induction of cell cycle arrest and the emergence of a senescence-associated secretory phenotype (SASP) that can develop in response to chemo- and targeted- therapies. A wide range of anticancer interventions can lead to cell cycle arrest and SASP induction, by inducing genotoxic stress, hyperactivation of signalling pathways or oxidative stress. TIS can be anti-tumorigenic in the short-term, but pro-tumorigenic in the long-term by creating a pro-inflammatory and immunosuppressive microenvironment. Moreover, the SASP can promote angiogenesis and epithelial-mesenchymal transition in neighbouring cells. In this review, we will describe the characteristics of TIS in breast cancer and detail the changes in phenotype that accompany its induction. We also discuss strategies for targeting senescent cancer cells in order to prevent or delay tumour recurrence.
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Affiliation(s)
- Suraj Narayanan Chembukavu
- Membrane Trafficking and Disease Laboratory, School of Biochemistry & Cell Biology, Biosciences Institute, University College Cork, Cork, T12 YT20, Ireland
| | - Andrew J Lindsay
- Membrane Trafficking and Disease Laboratory, School of Biochemistry & Cell Biology, Biosciences Institute, University College Cork, Cork, T12 YT20, Ireland
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2
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Hall BA, Senior KE, Ocampo NT, Samanta D. Coxiella burnetii-containing vacuoles interact with host recycling endosomal proteins Rab11a and Rab35 for vacuolar expansion and bacterial growth. Front Cell Infect Microbiol 2024; 14:1394019. [PMID: 38841112 PMCID: PMC11150555 DOI: 10.3389/fcimb.2024.1394019] [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: 02/29/2024] [Accepted: 05/01/2024] [Indexed: 06/07/2024] Open
Abstract
Introduction Coxiella burnetii is a gram-negative obligate intracellular bacterium and a zoonotic pathogen that causes human Q fever. The lack of effective antibiotics and a licensed vaccine for Coxiella in the U.S. warrants further research into Coxiella pathogenesis. Within the host cells, Coxiella replicates in an acidic phagolysosome-like vacuole termed Coxiella-containing vacuole (CCV). Previously, we have shown that the CCV pH is critical for Coxiella survival and that the Coxiella Type 4B secretion system regulates CCV pH by inhibiting the host endosomal maturation pathway. However, the trafficking pattern of the 'immature' endosomes in Coxiella- infected cells remained unclear. Methods We transfected HeLa cells with GFP-tagged Rab proteins and subsequently infected them with mCherry-Coxiella to visualize Rab protein localization. Infected cells were immunostained with anti-Rab antibodies to confirm the Rab localization to the CCV, to quantitate Rab11a and Rab35- positive CCVs, and to quantitate total recycling endosome content of infected cells. A dual-hit siRNA mediated knockdown combined with either immunofluorescent assay or an agarose-based colony-forming unit assay were used to measure the effects of Rab11a and Rab35 knockdown on CCV area and Coxiella intracellular growth. Results The CCV localization screen with host Rab proteins revealed that recycling endosome-associated proteins Rab11a and Rab35 localize to the CCV during infection, suggesting that CCV interacts with host recycling endosomes during maturation. Interestingly, only a subset of CCVs were Rab11a or Rab35-positive at any given time point. Quantitation of Rab11a/Rab35-positive CCVs revealed that while Rab11a interacts with the CCV more at 3 dpi, Rab35 is significantly more prevalent at CCVs at 6 dpi, suggesting that the CCV preferentially interacts with Rab11a and Rab35 depending on the stage of infection. Furthermore, we observed a significant increase in Rab11a and Rab35 fluorescent intensity in Coxiella-infected cells compared to mock, suggesting that Coxiella increases the recycling endosome content in infected cells. Finally, siRNA-mediated knockdown of Rab11a and Rab35 resulted in significantly smaller CCVs and reduced Coxiella intracellular growth, suggesting that recycling endosomal Rab proteins are essential for CCV expansion and bacterial multiplication. Discussion Our data, for the first time, show that the CCV dynamically interacts with host recycling endosomes for Coxiella intracellular survival and potentially uncovers novel host cell factors essential for Coxiella pathogenesis.
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Affiliation(s)
- Brooke A. Hall
- Department of Microbiology and Immunology, College of Graduate Studies, Midwestern University, Glendale, AZ, United States
| | - Kristen E. Senior
- Department of Microbiology and Immunology, College of Graduate Studies, Midwestern University, Glendale, AZ, United States
| | - Nicolle T. Ocampo
- Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ, United States
| | - Dhritiman Samanta
- Department of Microbiology and Immunology, College of Graduate Studies, Midwestern University, Glendale, AZ, United States
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3
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Li C, Zhou L, Yin X. Pathophysiological aspects of transferrin-A potential nano-based drug delivery signaling molecule in therapeutic target for varied diseases. Front Pharmacol 2024; 15:1342181. [PMID: 38500764 PMCID: PMC10944884 DOI: 10.3389/fphar.2024.1342181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
Transferrin (Tf), widely known for its role as an iron-binding protein, exemplifies multitasking in biological processes. The role of Tf in iron metabolism involves both the uptake of iron from Tf by various cells, as well as the endocytosis mediated by the complex of Tf and the transferrin receptor (TfR). The direct conjugation of the therapeutic compound and immunotoxin studies using Tf peptide or anti-Tf receptor antibodies as targeting moieties aims to prolong drug circulation time and augment efficient cellular drug uptake, diminish systemic toxicity, traverse the blood-brain barrier, restrict systemic exposure, overcome multidrug resistance, and enhance therapeutic efficacy with disease specificity. This review primarily discusses the various biological actions of Tf, as well as the development of Tf-targeted nano-based drug delivery systems. The goal is to establish the use of Tf as a disease-targeting component, accentuating the potential therapeutic applications of this protein.
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Affiliation(s)
- Chang Li
- Basic Medical College, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Liya Zhou
- Basic Medical College, Changchun University of Traditional Chinese Medicine, Changchun, China
| | - Xunzhe Yin
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
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4
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Edure T, Matsuno Y, Matsushita K, Maruyama N, Fujii W, Naito K, Sugiura K. Dynamics of extracellular vesicle uptake by mural granulosa cells in mice. Mol Reprod Dev 2024; 91:e23737. [PMID: 38450862 DOI: 10.1002/mrd.23737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/13/2024] [Accepted: 02/20/2024] [Indexed: 03/08/2024]
Abstract
Extracellular vesicles (EVs) play an important role in the development and function of mammalian ovarian follicles. However, the mechanisms by which they are taken up by the follicular granulosa cells remain unclear. In addition, while oocytes play a pivotal role in follicular development, the possible interactions between oocyte-derived paracrine factors (ODPFs) and EV signals are unknown. Therefore, this study aimed to elucidate the mechanism of EV uptake and the effects of ODPFs on EV uptake by follicular somatic mural granulosa cells in mice. Fluorescence-labeled transferrin (TRF) and cholera toxin B (CTB), substrates for clathrin- and caveolae-mediated endocytosis, respectively, were taken up by mural granulosa cells in vitro. Their uptake was inhibited by Pitstop 2 and genistein, inhibitors of clathrin and caveolae pathways, respectively. Mural granulosa cells took up EVs, and this uptake was suppressed by Pitstop 2 and genistein. Moreover, ODPFs promoted the uptake of EVs and CTB, but not TRF, by mural granulosa cells. These results suggest that mural granulosa cells take up EVs through both clathrin- and caveolae-mediated endocytosis and that oocytes may promote caveolae-mediated endocytosis to facilitate the uptake of EVs.
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Affiliation(s)
- Taichi Edure
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuta Matsuno
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Kodai Matsushita
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Natsumi Maruyama
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Wataru Fujii
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Kunihiko Naito
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Koji Sugiura
- Laboratory of Applied Genetics, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
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5
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Cantrell AC, Zeng H, Chen JX. The Therapeutic Potential of Targeting Ferroptosis in the Treatment of Mitochondrial Cardiomyopathies and Heart Failure. J Cardiovasc Pharmacol 2024; 83:23-32. [PMID: 37816193 PMCID: PMC10843296 DOI: 10.1097/fjc.0000000000001496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/28/2023] [Indexed: 10/12/2023]
Abstract
ABSTRACT Ferroptosis is a form of iron-regulated cell death implicated in a wide array of diseases, including heart failure, hypertension, and numerous cardiomyopathies. In addition, mitochondrial dysfunction has been associated with several of these same disease states. However, the role of the mitochondrion in ferroptotic cell death remains debated. As a major regulator of cellular iron levels, the mitochondria may very well play a crucial role in the mechanisms behind ferroptosis, but at this point, this has not been adequately defined. Emerging evidence from our laboratory and others indicates a critical role of mitochondrial Sirtuin 3, a deacetylase linked with longevity and protection against numerous conditions, in the prevention of cardiovascular diseases. Here, we provide a brief overview of the potential roles of Sirtuin 3 in mitochondrial iron homeostasis and its contribution to the mitochondrial cardiomyopathy of Friedreich's ataxia and diabetic cardiomyopathy. We also discuss the current knowledge of the involvement of ferroptosis and the mitochondria in these and other cardiovascular disease states, including doxorubicin-induced cardiomyopathy, and provide insight into areas requiring further investigation.
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Affiliation(s)
- Aubrey C Cantrell
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, School of Medicine, Jackson, MS
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6
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Skiba M, Guedes G, Karpov D, Feliu N, L. Cortajarena A, Parak WJ, Sanchez-Cano C. Probing the Cellular Fate of the Protein Corona around Nanoparticles with Nanofocused X-ray Fluorescence Imaging. Int J Mol Sci 2023; 25:528. [PMID: 38203697 PMCID: PMC10778884 DOI: 10.3390/ijms25010528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/22/2023] [Accepted: 12/28/2023] [Indexed: 01/12/2024] Open
Abstract
X-ray fluorescence imaging (XRF-imaging) with subcellular resolution is used to study the intracellular integrity of a protein corona that was pre-formed around gold nanoparticles (AuNP). Artificial proteins engineered to obtain Gd coordination for detection by XRF-imaging were used to form the corona. Indications about the degradation of this protein corona at a cellular and subcellular level can be observed by following the Au and Gd quantities in a time and spatial-dependent manner. The extended acquisition times necessary for capturing individual XRF-imaging cell images result in relatively small sample populations, stressing the need for faster image acquisition strategies in future XRF-imaging-based studies to deal with the inherent variability between cells. Still, results obtained reveal degradation of the protein corona during cellular trafficking, followed by differential cellular processing for AuNP and Gd-labelled proteins. Overall, this demonstrates that the dynamic degradation of the protein corona can be tracked by XRF-imaging to a certain degree.
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Affiliation(s)
- Marvin Skiba
- Center for Hybrid Nanostructures, University of Hamburg, 22761 Hamburg, Germany;
- The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany
| | - Gabriela Guedes
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), 20014 Donostia-San Sebastian, Spain
| | - Dmitry Karpov
- European Synchrotron Radiation Facility, 38000 Grenoble, France
| | - Neus Feliu
- Zentrum für Angewandte Nanotechnologie CAN, Fraunhofer-Institut für Angewandte Polymerforschung IAP, 20146 Hamburg, Germany
| | - Aitziber L. Cortajarena
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), 20014 Donostia-San Sebastian, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Wolfgang J. Parak
- Center for Hybrid Nanostructures, University of Hamburg, 22761 Hamburg, Germany;
- The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany
| | - Carlos Sanchez-Cano
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
- Donostia International Physics Center, 20018 Donostia-San Sebastian, Spain
- Polimero eta Material Aurreratuak: Fisika, Kimika eta Teknologia, Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, 20018 Donostia-San Sebastian, Spain
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7
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Leyton JV. The endosomal-lysosomal system in ADC design and cancer therapy. Expert Opin Biol Ther 2023; 23:1067-1076. [PMID: 37978880 DOI: 10.1080/14712598.2023.2285996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/16/2023] [Indexed: 11/19/2023]
Abstract
INTRODUCTION This discourse delves into the intricate connections between the endosomal-lysosomal system and antibody-drug conjugates (ADCs), shedding light on an essential yet less understood dimension of targeted therapy. While ADCs have revolutionized cancer treatment, resistance remains a formidable challenge, often involving diverse and overlapping mechanisms. AREAS COVERED This discourse highlights the roles of various components within the endosomal machinery, including Rab proteins, in ADC resistance development. It also explores how the transferrin-transferrin receptor and epidermal growth factor-epidermal growth factor receptor complexes, known for their roles in recycling and degradation process, respectively, can offer valuable insights for ADC design. Selected strategies to enhance lysosomal targeting are discussed, and potentially offer solutions to improve ADC efficacy. EXPERT OPINION By harnessing these different insights that connect ADCs with the endosomal-lysosomal system, the field may benefit to shape the next-generation of ADC design for increased efficacy and improved patient outcomes.
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Affiliation(s)
- Jeffrey V Leyton
- School of Pharmaceutical Sciences and Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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8
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Lemaigre C, Ceuppens A, Valades-Cruz CA, Ledoux B, Vanbeneden B, Hassan M, Zetterberg FR, Nilsson UJ, Johannes L, Wunder C, Renard HF, Morsomme P. N-BAR and F-BAR proteins-endophilin-A3 and PSTPIP1-control clathrin-independent endocytosis of L1CAM. Traffic 2023; 24:190-212. [PMID: 36843549 DOI: 10.1111/tra.12883] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/07/2023] [Accepted: 02/18/2023] [Indexed: 02/28/2023]
Abstract
Recent advances in the field demonstrate the high diversity and complexity of endocytic pathways. In the current study, we focus on the endocytosis of L1CAM. This glycoprotein plays a major role in the development of the nervous system, and is involved in cancer development and is associated with metastases and poor prognosis. Two L1CAM isoforms are subject to endocytosis: isoform 1, described as a clathrin-mediated cargo; isoform 2, whose endocytosis has never been studied. Deciphering the molecular machinery of isoform 2 internalisation should contribute to a better understanding of its pathophysiological role. First, we demonstrated in our cellular context that both isoforms of L1CAM are mainly a clathrin-independent cargo, which was not expected for isoform 1. Second, the mechanism of L1CAM endocytosis is specifically mediated by the N-BAR domain protein endophilin-A3. Third, we discovered PSTPIP1, an F-BAR domain protein, as a novel actor in this endocytic process. Finally, we identified galectins as endocytic partners and negative regulators of L1CAM endocytosis. In summary, the interplay of the BAR proteins endophilin-A3 and PSTPIP1, and galectins fine tune the clathrin-independent endocytosis of L1CAM.
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Affiliation(s)
- Camille Lemaigre
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Louvain-la-Neuve, Belgium
| | - Apolline Ceuppens
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Louvain-la-Neuve, Belgium
| | - Cesar Augusto Valades-Cruz
- Institut Curie, Université PSL, U1143 INSERM, UMR3666 CNRS, Cellular and Chemical Biology unit, Paris, France.,SERPICO Project Team, UMR144 CNRS Institut Curie, PSL Research University, Paris, France.,SERPICO Project Team, Inria Centre Rennes-Bretagne Atlantique, Campus Universitaire de Beaulieu, Rennes, France
| | - Benjamin Ledoux
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Louvain-la-Neuve, Belgium
| | - Bastien Vanbeneden
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Louvain-la-Neuve, Belgium
| | | | | | - Ulf J Nilsson
- Department of Chemistry, Lund University, Lund, Sweden
| | - Ludger Johannes
- Institut Curie, Université PSL, U1143 INSERM, UMR3666 CNRS, Cellular and Chemical Biology unit, Paris, France
| | - Christian Wunder
- Institut Curie, Université PSL, U1143 INSERM, UMR3666 CNRS, Cellular and Chemical Biology unit, Paris, France
| | - Henri-François Renard
- UNamur, NARILIS, Unité de recherche en biologie cellulaire animale (URBC), Namur, Belgium
| | - Pierre Morsomme
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Louvain-la-Neuve, Belgium
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Kumar A, Sarkar P, Chattopadhyay A. Metabolic depletion of sphingolipids inhibits agonist-induced endocytosis of the serotonin 1A receptor. Traffic 2023; 24:95-107. [PMID: 36533718 DOI: 10.1111/tra.12879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 10/11/2022] [Accepted: 10/18/2022] [Indexed: 12/23/2022]
Abstract
G protein-coupled receptors (GPCRs) are vital cellular signaling machinery and currently represent ~40% drug targets. Endocytosis of GPCRs is an important process that allows stringent spatiotemporal control over receptor population on the cell surface. Although the role of proteins in GPCR endocytosis is well addressed, the contribution of membrane lipids in this process is rather unexplored. Sphingolipids are essential functional lipids in higher eukaryotes and are implicated in several neurological functions. To understand the role of sphingolipids in GPCR endocytosis, we subjected cells expressing human serotonin1A receptors (an important neurotransmitter GPCR involved in cognitive and behavioral functions) to metabolic sphingolipid depletion using fumonisin B1 , an inhibitor of sphingolipid biosynthetic pathway. Our results, using flow cytometric analysis and confocal microscopic imaging, show that sphingolipid depletion inhibits agonist-induced endocytosis of the serotonin1A receptor in a concentration-dependent manner, which was restored when sphingolipid levels were replenished. We further show that there was no change in the internalization of transferrin, a marker for clathrin-mediated endocytosis, under sphingolipid-depleted condition, highlighting the specific requirement of sphingolipids for endocytosis of serotonin1A receptors. Our results reveal the regulatory role of sphingolipids in GPCR endocytosis and highlight the importance of neurotransmitter receptor trafficking in health and disease.
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Affiliation(s)
- Abhishek Kumar
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.,Amity Institute of Biotechnology, Amity University Haryana, Gurugram, India
| | - Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Amitabha Chattopadhyay
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
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O'Brien K, Ughetto S, Mahjoum S, Nair AV, Breakefield XO. Uptake, functionality, and re-release of extracellular vesicle-encapsulated cargo. Cell Rep 2022; 39:110651. [PMID: 35417683 PMCID: PMC9074118 DOI: 10.1016/j.celrep.2022.110651] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 08/06/2021] [Accepted: 03/18/2022] [Indexed: 12/19/2022] Open
Abstract
Extracellular vesicles (EVs) are membrane-encapsulated particles that carry genetically active and protein/lipid cargo that can affect the function of the recipient cell. A number of studies have described the effect of these vesicles on recipient cells and demonstrated their promise as therapeutic delivery vectors. Here we demonstrate functional delivery of EV-encapsulated RNA and protein cargo through use of luminescence and fluorescence reporters by combining organelle-targeted nanoluciferase with fluorescent proteins. We highlight a mechanism by which cells retain internalized cargo in the endosomal compartment for days, usually leading to content degradation. We also identify a mode through which recipient cells re-release internalized EVs intact after uptake. Highlighting these different fates of EVs in recipient cells sheds light on critical factors in steering functional cargo delivery and will ultimately allow more efficient use of EVs for therapeutic purposes.
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Affiliation(s)
- Killian O'Brien
- Molecular Neurogenetics Unit, Department of Neurology and Center for Molecular Imaging Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| | - Stefano Ughetto
- Department of Oncology, University of Turin, 10060 Candiolo, TO, Italy
| | - Shadi Mahjoum
- Molecular Neurogenetics Unit, Department of Neurology and Center for Molecular Imaging Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Anil V Nair
- Program in Membrane Biology, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Xandra O Breakefield
- Molecular Neurogenetics Unit, Department of Neurology and Center for Molecular Imaging Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
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11
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Chang HY, Wu S, Chowdhury EA, Shah DK. Towards a translational physiologically-based pharmacokinetic (PBPK) model for receptor-mediated transcytosis of anti-transferrin receptor monoclonal antibodies in the central nervous system. J Pharmacokinet Pharmacodyn 2022; 49:337-362. [DOI: 10.1007/s10928-021-09800-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 12/22/2021] [Indexed: 12/19/2022]
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12
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Sphingomyelin-Sequestered Cholesterol Domain Recruits Formin-Binding Protein 17 for Constricting Clathrin-Coated Pits in Influenza Virus Entry. J Virol 2022; 96:e0181321. [PMID: 35020471 DOI: 10.1128/jvi.01813-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Influenza A virus (IAV) is a global health threat. The cellular endocytic machineries harnessed by IAV remain elusive. Here, by tracking single IAV particles and quantifying the internalized IAV, we found that the sphingomyelin (SM)-sequestered cholesterol, but not the accessible cholesterol, is essential for the clathrin-mediated endocytosis (CME) of IAV. The clathrin-independent endocytosis of IAV is cholesterol-independent. Whereas, the CME of transferrin depends on SM-sequestered cholesterol and accessible cholesterol. Furthermore, three-color single-virus tracking and electron microscopy showed that the SM-cholesterol complex nanodomain is recruited to the IAV-containing clathrin-coated structure (CCS) and facilitates neck constriction of the IAV-containing CCS. Meanwhile, formin-binding protein 17 (FBP17), a membrane-bending protein which activates actin nucleation, is recruited to IAV-CCS complex in a manner dependent on the SM-cholesterol complex. We propose that the SM-cholesterol nanodomain at the neck of CCS recruits FBP17 to induce neck constriction by activating actin assembly. These results unequivocally show the physiological importance of the SM-cholesterol complex in IAV entry. Importance: IAV infects the cells by harnessing cellular endocytic machineries. Better understanding of the cellular machineries used for its entry might lead to the development of antiviral strategies, and would also provide important insights into physiological endocytic processes. This work demonstrated that a special pool of cholesterol in plasma membrane, SM-sequestered cholesterol, recruits FBP17 for the constriction of clathrin-coated pits in IAV entry. Meanwhile, the clathrin-independent cell entry of IAV is cholesterol-independent. The internalization of transferrin, the gold-standard cargo endocytosed solely via CME, is much less dependent on the SM-cholesterol complex. These results would provide new insights into IAV infection and pathway/cargo-specific involvement of cholesterol pool(s).
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Markworth R, Bähr M, Burk K. Held Up in Traffic-Defects in the Trafficking Machinery in Charcot-Marie-Tooth Disease. Front Mol Neurosci 2021; 14:695294. [PMID: 34483837 PMCID: PMC8415527 DOI: 10.3389/fnmol.2021.695294] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/23/2021] [Indexed: 12/13/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT), also known as motor and sensory neuropathy, describes a clinically and genetically heterogenous group of disorders affecting the peripheral nervous system. CMT typically arises in early adulthood and is manifested by progressive loss of motor and sensory functions; however, the mechanisms leading to the pathogenesis are not fully understood. In this review, we discuss disrupted intracellular transport as a common denominator in the pathogenesis of different CMT subtypes. Intracellular transport via the endosomal system is essential for the delivery of lipids, proteins, and organelles bidirectionally to synapses and the soma. As neurons of the peripheral nervous system are amongst the longest neurons in the human body, they are particularly susceptible to damage of the intracellular transport system, leading to a loss in axonal integrity and neuronal death. Interestingly, defects in intracellular transport, both in neurons and Schwann cells, have been found to provoke disease. This review explains the mechanisms of trafficking and subsequently summarizes and discusses the latest findings on how defects in trafficking lead to CMT. A deeper understanding of intracellular trafficking defects in CMT will expand our understanding of CMT pathogenesis and will provide novel approaches for therapeutic treatments.
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Affiliation(s)
- Ronja Markworth
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Katja Burk
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
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14
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Gorman BL, Brunet MA, Kraft ML. Depth correction of 3D NanoSIMS images using secondary electron pixel intensities. Biointerphases 2021; 16:041005. [PMID: 34344157 PMCID: PMC8337084 DOI: 10.1116/6.0001092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/22/2021] [Accepted: 07/07/2021] [Indexed: 11/17/2022] Open
Abstract
Strategies that do not require additional characterization to be performed on the sample or the collection of additional secondary ion signals are needed to depth correct 3D SIMS images of cells. Here, we develop a depth correction strategy that uses the pixel intensities in the secondary electron images acquired during negative-ion NanoSIMS depth profiling to reconstruct the sample morphology. This morphology reconstruction was then used to depth correct the 3D SIMS images that show the components of interest in the sample. As a proof of concept, we applied this approach to NanoSIMS depth profiling data that show the 15N-enrichment and 18O-enrichment from 15N-sphingolipids and 18O-cholesterol, respectively, within a metabolically labeled Madin-Darby canine kidney cell. Comparison of the cell morphology reconstruction to the secondary electron images collected with the NanoSIMS revealed that the assumption of a constant sputter rate produced small inaccuracies in sample morphology after approximately 0.66 μm of material was sputtered from the cell. Nonetheless, the resulting 3D renderings of the lipid-specific isotope enrichments better matched the shapes and positions of the subcellular compartments that contained 15N-sphingolipids and 18O-cholesterol than the uncorrected 3D SIMS images. This depth correction of the 3D SIMS images also facilitated the detection of spherical cholesterol-rich compartments that were surrounded by membranes containing cholesterol and sphingolipids. Thus, we expect this approach will facilitate identifying the subcellular structures that are enriched with biomolecules of interest in 3D SIMS images while eliminating the need for correlated analyses or additional secondary ion signals for the depth correction of 3D NanoSIMS images.
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Affiliation(s)
- Brittney L Gorman
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Melanie A Brunet
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Mary L Kraft
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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15
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Mechanisms and Regulation of Cardiac Ca V1.2 Trafficking. Int J Mol Sci 2021; 22:ijms22115927. [PMID: 34072954 PMCID: PMC8197997 DOI: 10.3390/ijms22115927] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 01/05/2023] Open
Abstract
During cardiac excitation contraction coupling, the arrival of an action potential at the ventricular myocardium triggers voltage-dependent L-type Ca2+ (CaV1.2) channels in individual myocytes to open briefly. The level of this Ca2+ influx tunes the amplitude of Ca2+-induced Ca2+ release from ryanodine receptors (RyR2) on the junctional sarcoplasmic reticulum and thus the magnitude of the elevation in intracellular Ca2+ concentration and ultimately the downstream contraction. The number and activity of functional CaV1.2 channels at the t-tubule dyads dictates the amplitude of the Ca2+ influx. Trafficking of these channels and their auxiliary subunits to the cell surface is thus tightly controlled and regulated to ensure adequate sarcolemmal expression to sustain this critical process. To that end, recent discoveries have revealed the existence of internal reservoirs of preformed CaV1.2 channels that can be rapidly mobilized to enhance sarcolemmal expression in times of acute stress when hemodynamic and metabolic demand increases. In this review, we provide an overview of the current thinking on CaV1.2 channel trafficking dynamics in the heart. We highlight the numerous points of control including the biosynthetic pathway, the endosomal recycling pathway, ubiquitination, and lysosomal and proteasomal degradation pathways, and discuss the effects of β-adrenergic and angiotensin receptor signaling cascades on this process.
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16
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Qi T, Cao Y. In Translation: FcRn across the Therapeutic Spectrum. Int J Mol Sci 2021; 22:3048. [PMID: 33802650 PMCID: PMC8002405 DOI: 10.3390/ijms22063048] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 12/14/2022] Open
Abstract
As an essential modulator of IgG disposition, the neonatal Fc receptor (FcRn) governs the pharmacokinetics and functions many therapeutic modalities. In this review, we thoroughly reexamine the hitherto elucidated biological and thermodynamic properties of FcRn to provide context for our assessment of more recent advances, which covers antigen-binding fragment (Fab) determinants of FcRn affinity, transgenic preclinical models, and FcRn targeting as an immune-complex (IC)-clearing strategy. We further comment on therapeutic antibodies authorized for treating SARS-CoV-2 (bamlanivimab, casirivimab, and imdevimab) and evaluate their potential to saturate FcRn-mediated recycling. Finally, we discuss modeling and simulation studies that probe the quantitative relationship between in vivo IgG persistence and in vitro FcRn binding, emphasizing the importance of endosomal transit parameters.
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Affiliation(s)
| | - Yanguang Cao
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA;
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17
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De Leo MG, Berger P, Mayer A. WIPI1 promotes fission of endosomal transport carriers and formation of autophagosomes through distinct mechanisms. Autophagy 2021; 17:3644-3670. [PMID: 33685363 PMCID: PMC8632285 DOI: 10.1080/15548627.2021.1886830] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autophagosome formation requires PROPPIN/WIPI proteins and monophosphorylated phosphoinositides, such as phosphatidylinositol-3-phosphate (PtdIns3P) or PtdIns5P. This process occurs in association with mammalian endosomes, where the PROPPIN WIPI1 has additional, undefined roles in vesicular traffic. To explore whether these functions are interconnected, we dissected routes and subreactions of endosomal trafficking requiring WIPI1. WIPI1 specifically acts in the formation and fission of tubulo-vesicular endosomal transport carriers. This activity supports the PtdIns(3,5)P2-dependent transport of endosomal cargo toward the plasma membrane, Golgi, and lysosomes, suggesting a general role of WIPI1 in endosomal protein exit. Three features differentiate the endosomal and macroautophagic/autophagic activities of WIPI1: phosphoinositide binding site II, the requirement for PtdIns(3,5)P2, and bilayer deformation through a conserved amphipathic α-helix. Their inactivation preserves autophagy but leads to a strong enlargement of endosomes, which accumulate micrometer-long endosomal membrane tubules carrying cargo proteins. WIPI1 thus supports autophagy and protein exit from endosomes by different modes of action. We propose that the type of phosphoinositides occupying its two lipid binding sites, the most unusual feature of PROPPIN/WIPI family proteins, switches between these effector functions. Abbreviations: EGF: epidermal growth factorEGFR: epidermal growth factor receptorKD: knockdownKO: knockoutPtdIns3P: phosphatidylinositol-3-phosphatePtdIns5P: phosphatidylinositol-5-phosphatePtdIns(3,5)P2: phosphatidylinositol-3,5-bisphosphateTF: transferrinTFRC: transferrin receptorWT: wildtype
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Affiliation(s)
| | - Philipp Berger
- Department of Biology and Chemistry, Laboratory of Nanoscale Biology, Paul-Scherrer-Institute, Villigen, Switzerland
| | - Andreas Mayer
- Département De Biochimie, Université De Lausanne, Lausanne, Epalinges, Switzerland
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18
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Kumar GA, Chattopadhyay A. Membrane cholesterol regulates endocytosis and trafficking of the serotonin 1A receptor: Insights from acute cholesterol depletion. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158882. [PMID: 33429076 DOI: 10.1016/j.bbalip.2021.158882] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/24/2020] [Accepted: 01/06/2021] [Indexed: 12/12/2022]
Abstract
Endocytosis and intracellular trafficking constitute important regulatory features associated with G protein-coupled receptor (GPCR) function. GPCR endocytosis involves several remodeling events at the plasma membrane orchestrated by a concerted interplay of a large number of proteins and membrane lipids. Although considerable literature exists on the protein framework underlying GPCR endocytosis, the role of membrane lipids in this process remains largely unexplored. In order to explore the role of membrane cholesterol (an essential and important lipid in higher eukaryotes) in GPCR endocytosis, we monitored the effect of acute cholesterol depletion using methyl-β-cyclodextrin (MβCD) on endocytosis and intracellular trafficking of the serotonin1A receptor, an important neurotransmitter GPCR. Our results show that the serotonin1A receptor exhibits agonist-induced clathrin-mediated endocytosis with a concentration-dependent inhibition in internalization with increasing concentrations of MβCD, which was restored upon cholesterol replenishment. Interestingly, subsequent to internalization under these conditions, serotonin1A receptors were re-routed toward lysosomal degradation, instead of endosomal recycling observed under normal conditions, thereby implicating membrane cholesterol in modulation of intracellular trafficking of the receptor. This raises the possibility of a novel cholesterol-dependent role of intracellular sorting proteins in GPCR trafficking. These results differ from our previous observations on the endocytosis of the serotonin1A receptor upon statin-induced chronic cholesterol depletion, in terms of endocytic pathway. We conclude that analysis of complex cellular trafficking events such as GPCR endocytosis under acute and chronic cholesterol depletion conditions should be carried out with caution due to fundamental differences underlying these processes.
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Affiliation(s)
- G Aditya Kumar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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19
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Mannose-Decorated Dendritic Polyglycerol Nanocarriers Drive Antiparasitic Drugs To Leishmania infantum-Infected Macrophages. Pharmaceutics 2020; 12:pharmaceutics12100915. [PMID: 32987800 PMCID: PMC7598597 DOI: 10.3390/pharmaceutics12100915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 09/11/2020] [Accepted: 09/21/2020] [Indexed: 02/07/2023] Open
Abstract
Macrophages are hosts for intracellular pathogens involved in numerous diseases including leishmaniasis. They express surface receptors that may be exploited for specific drug-targeting. Recently, we developed a PEGylated dendritic polyglycerol-based conjugate (PG–PEG) that colocalizes with intracellular parasite. We hereby study the effect of surface decoration with mannose units on the conjugates’ targeting ability toward leishmania intracellular parasites. Murine and human macrophages were exposed to fluorescently labeled mannosylated PG–PEG and uptake was quantified by flow cytometry analysis. Nanocarriers bearing five mannose units showed the highest uptake, which varied between 30 and 88% in the population in human and murine macrophages, respectively. The uptake was found to be dependent on phagocytosis and pinocytosis (80%), as well as clathrin-mediated endocytosis (79%). Confocal microscopy showed that mannosylated PG–PEGs target acidic compartments in macrophages. In addition, when both murine and human macrophages were infected and treated, colocalization between parasites and mannosylated nanoconjugates was observed. Leishmania-infected bone marrow-derived macrophages (BMM) showed avidity by mannosylated PG–PEG whereas non-infected macrophages rarely accumulated conjugates. Moreover, the antileishmanial activity of Amphotericin B was kept upon conjugation to mannosylated PG–PEG through a pH-labile linker. This study demonstrates that leishmania infected macrophages are selectively targeted by mannosylated PEGylated dendritic conjugates.
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20
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Targeting Receptors on Cancer Cells with Protein Toxins. Biomolecules 2020; 10:biom10091331. [PMID: 32957689 PMCID: PMC7563326 DOI: 10.3390/biom10091331] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/12/2020] [Accepted: 09/16/2020] [Indexed: 02/07/2023] Open
Abstract
Cancer cells frequently upregulate surface receptors that promote growth and survival. These receptors constitute valid targets for intervention. One strategy involves the delivery of toxic payloads with the goal of killing those cancer cells with high receptor levels. Delivery can be accomplished by attaching a toxic payload to either a receptor-binding antibody or a receptor-binding ligand. Generally, the cell-binding domain of the toxin is replaced with a ligand or antibody that dictates a new binding specificity. The advantage of this “immunotoxin” approach lies in the potency of these chimeric molecules for killing cancer cells. However, receptor expression on normal tissue represents a significant obstacle to therapeutic intervention.
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21
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Sposini S, Rosendale M, Claverie L, Van TNN, Jullié D, Perrais D. Imaging endocytic vesicle formation at high spatial and temporal resolutions with the pulsed-pH protocol. Nat Protoc 2020; 15:3088-3104. [PMID: 32807908 DOI: 10.1038/s41596-020-0371-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/04/2020] [Indexed: 11/09/2022]
Abstract
Endocytosis is a fundamental process occurring in all eukaryotic cells. Live cell imaging of endocytosis has helped to decipher many of its mechanisms and regulations. With the pulsed-pH (ppH) protocol, one can detect the formation of individual endocytic vesicles (EVs) with an unmatched temporal resolution of 2 s. The ppH protocol makes use of cargo protein (e.g., the transferrin receptor) coupled to a pH-sensitive fluorescent protein, such as superecliptic pHluorin (SEP), which is brightly fluorescent at pH 7.4 but not fluorescent at pH <6.0. If the SEP moiety is at the surface, its fluorescence will decrease when cells are exposed to a low pH (5.5) buffer. If the SEP moiety has been internalized, SEP will remain fluorescent even during application of the low pH buffer. Fast perfusion enables the complete exchange of low and high pH extracellular solutions every 2 s, defining the temporal resolution of the technique. Unlike other imaging-based endocytosis assays, the ppH protocol detects EVs without a priori hypotheses on the dynamics of vesicle formation. Here, we explain how the ppH protocol quantifies the endocytic activity of living cells and the recruitment of associated proteins in real time. We provide a step-by-step procedure for expression of the reporter proteins with transient transfection, live cell image acquisition with synchronized pH changes and automated analysis. The whole protocol can be performed in 2 d to provide quantitative information on the endocytic process being studied.
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Affiliation(s)
- Silvia Sposini
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France
| | - Morgane Rosendale
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Institut des Sciences Moléculaires, UMR 5255, Talence, France
| | - Léa Claverie
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,Euroquality, Bordeaux, France
| | - Thi Nhu Ngoc Van
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,Sys2diag, Montpellier, France
| | - Damien Jullié
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.,University of California, San Francisco, San Francisco, CA, USA
| | - David Perrais
- University of Bordeaux, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France. .,CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, Bordeaux, France.
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22
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Arta A, Larsen JB, Eriksen AZ, Kempen PJ, Larsen M, Andresen TL, Urquhart AJ. Cell targeting strategy affects the intracellular trafficking of liposomes altering loaded doxorubicin release kinetics and efficacy in endothelial cells. Int J Pharm 2020; 588:119715. [PMID: 32750439 DOI: 10.1016/j.ijpharm.2020.119715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/20/2020] [Accepted: 07/28/2020] [Indexed: 11/30/2022]
Abstract
Targeting nanocarrier drug delivery systems, that deliver drug payloads to the site of disease action, are frequently viewed as the future of nanocarrier based therapies but have struggled to breakthrough to the clinic in comparison to non-targeting counterparts. Using unilamellar liposomes as model nanocarriers, we show that cell targeting strategy (electrostatic, ligand and antigen) influences both the intracellular fate of the liposomes and the corresponding efficacy of the loaded drug, doxorubicin, in endothelial cells. We show that increased liposome uptake by cells does not translate to improved efficacy in this scenario but that liposome intracellular trafficking, particularly distribution between recycling endosomes and lysosomes, influences in vitro efficacy. Choosing targeting strategies that promote desired nanocarrier intracellular trafficking may be a viable strategy to enhance the in vivo efficacy of drug delivery systems.
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Affiliation(s)
- Anthoula Arta
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark
| | - Jannik B Larsen
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark
| | - Anne Z Eriksen
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark
| | - Paul J Kempen
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark
| | - Michael Larsen
- Department of Opthalmology, Rigshospitalet, Glostrup, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas L Andresen
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark
| | - Andrew J Urquhart
- Department of Health Technology, Technical University of Denmark, Building 345C, 2800 Kgs. Lyngby, Denmark.
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23
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Bano S, Obaid G, Swain JWR, Yamada M, Pogue BW, Wang K, Hasan T. NIR Photodynamic Destruction of PDAC and HNSCC Nodules Using Triple-Receptor-Targeted Photoimmuno-Nanoconjugates: Targeting Heterogeneity in Cancer. J Clin Med 2020; 9:E2390. [PMID: 32726945 PMCID: PMC7464411 DOI: 10.3390/jcm9082390] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 07/17/2020] [Indexed: 12/22/2022] Open
Abstract
Receptor heterogeneity in cancer is a major limitation of molecular targeting for cancer therapeutics. Single-receptor-targeted treatment exerts selection pressures that result in treatment escape for low-receptor-expressing tumor subpopulations. To overcome this potential for heterogeneity-driven resistance to molecular targeted photodynamic therapy (PDT), we present for the first time a triple-receptor-targeted photoimmuno-nanoconjugate (TR-PIN) platform. TR-PIN functionalization with cetuximab, holo-transferrin, and trastuzumab conferred specificity for epidermal growth factor receptor (EGFR), transferrin receptor (TfR), and human epidermal growth factor receptor 2 (HER-2), respectively. The TR-PINs exhibited up to a 24-fold improvement in cancer cell binding compared with EGFR-specific cetuximab-targeted PINs (Cet-PINs) in low-EGFR-expressing cell lines. Photodestruction using TR-PINs was significantly higher than the monotargeted Cet-PINs in heterocellular 3D in vitro models of heterogeneous pancreatic ductal adenocarcinoma (PDAC; MIA PaCa-2 cells) and heterogeneous head and neck squamous cell carcinoma (HNSCC, SCC9 cells) containing low-EGFR-expressing T47D (high TfR) or SKOV-3 (high HER-2) cells. Through their capacity for multiple tumor target recognition, TR-PINs can serve as a unique and amenable platform for the effective photodynamic eradication of diverse tumor subpopulations in heterogeneous cancers to mitigate escape for more complete and durable treatment responses.
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Affiliation(s)
- Shazia Bano
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; (S.B.); (G.O.); (J.W.R.S.); (M.Y.)
| | - Girgis Obaid
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; (S.B.); (G.O.); (J.W.R.S.); (M.Y.)
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX 75080, USA
| | - Joseph W. R. Swain
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; (S.B.); (G.O.); (J.W.R.S.); (M.Y.)
| | - Marina Yamada
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; (S.B.); (G.O.); (J.W.R.S.); (M.Y.)
- Department of Health Sciences, Northeastern University, Boston, MA 02115, USA
| | - Brian W. Pogue
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA;
| | - Kenneth Wang
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN 55905, USA;
| | - Tayyaba Hasan
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; (S.B.); (G.O.); (J.W.R.S.); (M.Y.)
- Division of Health Sciences and Technology, Harvard University and Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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24
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Eversole D, Subramanian K, Harrison RK, Bourgeois F, Yuksel A, Ben-Yakar A. Femtosecond Plasmonic Laser Nanosurgery (fs-PLN) mediated by molecularly targeted gold nanospheres at ultra-low pulse fluences. Sci Rep 2020; 10:12387. [PMID: 32709944 PMCID: PMC7382507 DOI: 10.1038/s41598-020-68512-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 06/25/2020] [Indexed: 12/16/2022] Open
Abstract
Plasmonic Laser Nanosurgery (PLN) is a novel photomodification technique that exploits the near-field enhancement of femtosecond (fs) laser pulses in the vicinity of gold nanoparticles. While prior studies have shown the advantages of fs-PLN to modify cells, further reduction in the pulse fluence needed to initiate photomodification is crucial to facilitate deep–tissue treatments. This work presents an in-depth study of fs-PLN at ultra-low pulse fluences using 47 nm gold nanoparticles, conjugated to antibodies that target the epithelial growth factor receptor and excited off-resonance using 760 nm, 270 fs laser pulses at 80 MHz repetition rate. We find that fs-PLN can optoporate cellular membranes with pulse fluences as low as 1.3 mJ/cm2, up to two orders of magnitude lower than those used at lower repetition rates. Our results, corroborated by simulations of free-electron generation by particle photoemission and photoionization of the surrounding water, shed light on the off-resonance fs-PLN mechanism. We suggest that photo-chemical pathways likely drive cellular optoporation and cell damage at these off-resonance, low fluence, and high repetition rate fs-laser pulses, with clusters acting as local concentrators of ROS generation. We believe that the low fluence and highly localized ROS-mediated fs-PLN approach will enable targeted therapeutics and cancer treatment.
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Affiliation(s)
- Daniel Eversole
- Biomedical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Kaushik Subramanian
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Rick K Harrison
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Frederic Bourgeois
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Anil Yuksel
- Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA
| | - Adela Ben-Yakar
- Biomedical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA. .,Mechanical Engineering, The University of Texas At Austin, Austin, TX, 78712, USA.
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25
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Kaźmierczak Z, Szostak-Paluch K, Przybyło M, Langner M, Witkiewicz W, Jędruchniewicz N, Dąbrowska K. Endocytosis in cellular uptake of drug delivery vectors: Molecular aspects in drug development. Bioorg Med Chem 2020; 28:115556. [PMID: 32828419 DOI: 10.1016/j.bmc.2020.115556] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 12/16/2022]
Abstract
Drug delivery vectors are widely applied to increase drug efficacy while reducing the side effects and potential toxicity of a drug. They allow for patient-tailored therapy, dose titration, and therapeutic drug monitoring. A major part of drug delivery systems makes use of large nanocarriers: liposomes or virus-like particles (VLPs). These systems allow for a relatively large amount of cargo with good stability of vectors, and they offer multiple options for targeting vectors in vivo. Here we discuss endocytic pathways that are available for drug delivery by large nanocarriers. We focus on molecular aspects of the process, including an overview of potential molecular targets for studies of drug delivery vectors and for future solutions allowing targeted drug delivery.
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Affiliation(s)
- Zuzanna Kaźmierczak
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Kamila Szostak-Paluch
- Research and Development Center, Regional Specialized Hospital, Wrocław, Poland; Wrocław University of Science and Technology, Faculty of Fundamental Technical Problems, Department of Biomedical Engineering, Wrocław, Poland
| | - Magdalena Przybyło
- Wrocław University of Science and Technology, Faculty of Fundamental Technical Problems, Department of Biomedical Engineering, Wrocław, Poland; Lipid Systems sp z o.o., Wrocław, Poland
| | - Marek Langner
- Wrocław University of Science and Technology, Faculty of Fundamental Technical Problems, Department of Biomedical Engineering, Wrocław, Poland; Lipid Systems sp z o.o., Wrocław, Poland
| | - Wojciech Witkiewicz
- Research and Development Center, Regional Specialized Hospital, Wrocław, Poland
| | | | - Krystyna Dąbrowska
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland; Research and Development Center, Regional Specialized Hospital, Wrocław, Poland.
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26
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Zackova Suchanova J, Hejtmankova A, Neburkova J, Cigler P, Forstova J, Spanielova H. The Protein Corona Does Not Influence Receptor-Mediated Targeting of Virus-like Particles. Bioconjug Chem 2020; 31:1575-1585. [DOI: 10.1021/acs.bioconjchem.0c00240] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Jirina Zackova Suchanova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Alzbeta Hejtmankova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Jitka Neburkova
- Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Petr Cigler
- Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Jitka Forstova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Hana Spanielova
- Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
- Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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27
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Kumar GA, Chattopadhyay A. Statin-Induced Chronic Cholesterol Depletion Switches GPCR Endocytosis and Trafficking: Insights from the Serotonin 1A Receptor. ACS Chem Neurosci 2020; 11:453-465. [PMID: 31880914 DOI: 10.1021/acschemneuro.9b00659] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Endocytosis is a key regulatory mechanism adopted by G protein-coupled receptors (GPCRs) to modulate downstream signaling responses within a stringent spatiotemporal regime. Although the role of membrane lipids has been extensively studied in the context of the function, organization, and dynamics of GPCRs, their role in receptor endocytosis remains largely unexplored. Cholesterol, the predominant sterol in higher eukaryotes, plays a crucial role in maintaining the structure and organization of cell membranes and is involved in essential cellular processes in health and disease. The serotonin1A receptor is a representative GPCR involved in neuronal development and in neuropsychiatric disorders such as anxiety and depression. We recently combined quantitative flow cytometric and confocal microscopic approaches to demonstrate that the serotonin1A receptor undergoes clathrin-mediated endocytosis upon agonist stimulation and subsequently traffics along the endosomal recycling pathway. In this work, we show that statin-induced chronic cholesterol depletion switches the endocytic pathway of the serotonin1A receptor from clathrin- to caveolin-mediated endocytosis. Interestingly, under these conditions, a significant proportion of endocytosed receptors is rerouted toward lysosomal degradation. To the best of our knowledge, these results constitute one of the first comprehensive reports on the role of membrane cholesterol in GPCR endocytosis and trafficking. These results are significant in our overall understanding of the modulatory effects of membrane lipids on GPCR endocytosis and trafficking and could provide novel insight in developing therapeutic interventions against neuropsychiatric disorders such as depression.
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Affiliation(s)
- G. Aditya Kumar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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28
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Fong VH, Wong S, Jintaridhi P, Vieira A. Transport of the Thyroid Hormone Carrier Protein Transthyretin into Human Epidermoid Cells. Endocr Res 2020; 45:131-136. [PMID: 31762320 DOI: 10.1080/07435800.2019.1694538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Purpose: Transthyretin (TTR) is a protein with a growing number of biological functions in addition to its well-established binding and circulatory transport of thyroxine, and indirect retinoid transport through interaction with retinol-binding protein. Misfolded and aggregated wild-type and mutant TTRs are involved in amyloid diseases. Several aspects of TTR pathology and physiology remain poorly understood. Receptor-mediated cellular transport of TTR has been described in a few cell types; and such studies suggest the possibility of different TTR receptors and endocytic pathways. Our main objective was to further understand the endocytic pathways for TTR.Methods: In the current study, analyses of TTR endocytic transport were performed in the human A431 cell line. The results of TTR uptake were compared with those of the iron-carrier protein transferrin (Tf, a common stardard for endocytosis studies) in the same cell types.Results: A comparison of TTR and Tf endocytosis suggested similar early, 5-10 min, accumulation kinetics. But at a later time, 30 min, TTR accumulation was 20-30% lower than that of Tf (p < .05), a result that suggests different post-endocytic fates for these two ligands. Through the use of multiple endocytosis inhibitors, biochemical evidence is provided for an internalization pathway that differs from the clathrin-mediated endocytosis of Tf.Conclusions: These results for A431 cells are compared with others reported for different cell types; and it is suggested that this same hormone carrier protein can transit into cells through multiple endocytic pathways.
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Affiliation(s)
- Vai Hong Fong
- Biomedical Physiology BPK, Simon Fraser University, Burnaby, BC, Canada
- Department of Neurology, Far Eastern Memorial University Hospital, New Taipei City, Taiwan
| | - Shaun Wong
- Biomedical Physiology BPK, Simon Fraser University, Burnaby, BC, Canada
| | | | - Amandio Vieira
- Biomedical Physiology BPK, Simon Fraser University, Burnaby, BC, Canada
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29
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Jonker CTH, Deo C, Zager PJ, Tkachuk AN, Weinstein AM, Rodriguez-Boulan E, Lavis LD, Schreiner R. Accurate measurement of fast endocytic recycling kinetics in real time. J Cell Sci 2020; 133:jcs.231225. [PMID: 31843759 DOI: 10.1242/jcs.231225] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 12/09/2019] [Indexed: 01/01/2023] Open
Abstract
The fast turnover of membrane components through endocytosis and recycling allows precise control of the composition of the plasma membrane. Endocytic recycling can be rapid, with some molecules returning to the plasma membrane with a half time <5 min. Existing methods to study these trafficking pathways utilize chemical, radioactive or fluorescent labeling of cell surface receptors in pulse-chase experiments, which require tedious washing steps and manual collection of samples. Here, we introduce a live-cell endocytic recycling assay based on a newly designed cell-impermeable fluorogenic ligand for HaloTag, Janelia Fluor 635i (JF635i, where i indicates impermeant), which allows real-time detection of membrane receptor recycling at steady state. We used this method to study the effect of iron depletion on transferrin receptor (TfR) recycling using the chelator desferrioxamine. We found that this perturbation significantly increases the TfR recycling rate. The high temporal resolution and simplicity of this assay provides a clear advantage over extant methods and makes it ideal for large scale cellular imaging studies. This assay can be adapted to examine other cellular kinetic parameters such as protein turnover and biosynthetic trafficking.
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Affiliation(s)
- Caspar T H Jonker
- Weill Cornell Medicine, Department of Ophthalmology, Margaret Dyson Vision Research Institute, New York, NY, 10065, USA
| | - Claire Deo
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, United States
| | - Patrick J Zager
- Weill Cornell Medicine, Department of Ophthalmology, Margaret Dyson Vision Research Institute, New York, NY, 10065, USA
| | - Ariana N Tkachuk
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, United States
| | - Alan M Weinstein
- Department of Physiology and Biophysics, Department of Medicine, Weill Cornell Medicine, New York, New York 10065, USA
| | - Enrique Rodriguez-Boulan
- Weill Cornell Medicine, Department of Ophthalmology, Margaret Dyson Vision Research Institute, New York, NY, 10065, USA
| | - Luke D Lavis
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, United States
| | - Ryan Schreiner
- Weill Cornell Medicine, Department of Ophthalmology, Margaret Dyson Vision Research Institute, New York, NY, 10065, USA
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30
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Release of trivalent chromium from serum transferrin is sufficiently rapid to be physiologically relevant. J Inorg Biochem 2020; 202:110901. [DOI: 10.1016/j.jinorgbio.2019.110901] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/24/2019] [Accepted: 10/17/2019] [Indexed: 12/18/2022]
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31
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Luxán G, Stewen J, Díaz N, Kato K, Maney SK, Aravamudhan A, Berkenfeld F, Nagelmann N, Drexler HC, Zeuschner D, Faber C, Schillers H, Hermann S, Wiseman J, Vaquerizas JM, Pitulescu ME, Adams RH. Endothelial EphB4 maintains vascular integrity and transport function in adult heart. eLife 2019; 8:45863. [PMID: 31782728 PMCID: PMC6884395 DOI: 10.7554/elife.45863] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 11/15/2019] [Indexed: 12/17/2022] Open
Abstract
The homeostasis of heart and other organs relies on the appropriate provision of nutrients and functional specialization of the local vasculature. Here, we have used mouse genetics, imaging and cell biology approaches to investigate how homeostasis in the adult heart is controlled by endothelial EphB4 and its ligand ephrin-B2, which are known regulators of vascular morphogenesis and arteriovenous differentiation during development. We show that inducible and endothelial cell-specific inactivation of Ephb4 in adult mice is compatible with survival, but leads to rupturing of cardiac capillaries, cardiomyocyte hypertrophy, and pathological cardiac remodeling. In contrast, EphB4 is not required for integrity and homeostasis of capillaries in skeletal muscle. Our analysis of mutant mice and cultured endothelial cells shows that EphB4 controls the function of caveolae, cell-cell adhesion under mechanical stress and lipid transport. We propose that EphB4 maintains critical functional properties of the adult cardiac vasculature and thereby prevents dilated cardiomyopathy-like defects.
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Affiliation(s)
- Guillermo Luxán
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Jonas Stewen
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Noelia Díaz
- Regulatory Genomics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Katsuhiro Kato
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Sathish K Maney
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Anusha Aravamudhan
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Frank Berkenfeld
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Nina Nagelmann
- Department of Clinical Radiology, University Hospital Münster, Münster, Germany
| | - Hannes Ca Drexler
- Bioanalytical Mass Spectrometry Unit, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Dagmar Zeuschner
- Electron Microscopy Unit, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Cornelius Faber
- Department of Clinical Radiology, University Hospital Münster, Münster, Germany
| | - Hermann Schillers
- Institute for Physiology II, University of Münster, Münster, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging, University of Münster, Münster, Germany
| | - John Wiseman
- Discovery Biology, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Juan M Vaquerizas
- Regulatory Genomics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Mara E Pitulescu
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany.,Faculty of Medicine, University of Münster, Münster, Germany
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32
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Landi A, Mari M, Kleiser S, Wolf T, Gretzmeier C, Wilhelm I, Kiritsi D, Thünauer R, Geiger R, Nyström A, Reggiori F, Claudinon J, Römer W. Pseudomonas aeruginosa lectin LecB impairs keratinocyte fitness by abrogating growth factor signalling. Life Sci Alliance 2019; 2:2/6/e201900422. [PMID: 31732693 PMCID: PMC6858607 DOI: 10.26508/lsa.201900422] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 12/22/2022] Open
Abstract
Lectins are glycan-binding proteins with no catalytic activity and ubiquitously expressed in nature. Numerous bacteria use lectins to efficiently bind to epithelia, thus facilitating tissue colonisation. Wounded skin is one of the preferred niches for Pseudomonas aeruginosa, which has developed diverse strategies to impair tissue repair processes and promote infection. Here, we analyse the effect of the P. aeruginosa fucose-binding lectin LecB on human keratinocytes and demonstrate that it triggers events in the host, upon binding to fucosylated residues on cell membrane receptors, which extend beyond its role as an adhesion molecule. We found that LecB associates with insulin-like growth factor-1 receptor and dampens its signalling, leading to the arrest of cell cycle. In addition, we describe a novel LecB-triggered mechanism to down-regulate host cell receptors by showing that LecB leads to insulin-like growth factor-1 receptor internalisation and subsequent missorting towards intracellular endosomal compartments, without receptor activation. Overall, these data highlight that LecB is a multitask virulence factor that, through subversion of several host pathways, has a profound impact on keratinocyte proliferation and survival.
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Affiliation(s)
- Alessia Landi
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Muriel Mari
- Department of Biomedical Sciences of Cells & Systems, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
| | - Svenja Kleiser
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Tobias Wolf
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Christine Gretzmeier
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Isabel Wilhelm
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine, University of Freiburg, Freiburg, Germany
| | - Dimitra Kiritsi
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Roland Thünauer
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Roger Geiger
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Alexander Nyström
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells & Systems, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
| | - Julie Claudinon
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Winfried Römer
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany .,Signalling Research Centres, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies , Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine, University of Freiburg, Freiburg, Germany
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33
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Yuan D, Rode F, Cao Y. A systems pharmacokinetic/pharmacodynamic model for concizumab to explore the potential of anti-TFPI recycling antibodies. Eur J Pharm Sci 2019; 138:105032. [PMID: 31394258 PMCID: PMC6824202 DOI: 10.1016/j.ejps.2019.105032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 07/22/2019] [Accepted: 08/01/2019] [Indexed: 01/31/2023]
Abstract
Concizumab is a humanized monoclonal antibody in clinical investigation directed against membrane-bound and soluble tissue factor pathway inhibitor (mTFPI and sTFPI) for treatment of hemophilia. Concizumab displays a non-linear pharmacokinetic (PK) profile due to mTFPI-mediated endocytosis and necessitates a high dose and frequent dosing to suppress the abundant sTFPI, a negative regulator of coagulation. Recycling antibodies that can dissociate bound mTFPI/sTFPI in endosomes for degradation and rescue antibody from degradation have a potential in reducing the dose by extending antibody systemic persistence and sTFPI suppression. We developed a systems PK/pharmacodynamics (PD) model with nested endosome compartments to simulate the effect of decreased antibody binding to mTFPI/sTFPI in endosomes on antibody clearance and sTFPI suppression for exploring the potential of anti-TFPI recycling antibodies in reducing the dose. A dynamic model-building strategy was taken. A reduced PK/PD model without the endosome compartments was developed to optimize unknown target turnover parameters using concizumab PK data. The optimized parameters were then employed in the systems PK/PD model for simulations. The obtained systems PK/PD model adequately described the PK of concizumab in rabbits, monkeys, and humans and the PD in humans. The systems PK/PD model predicted that an anti-TFPI recycling antibody with a 100-fold higher mTFPI/sTFPI dissociation constant in endosomes than concizumab can extend sTFPI suppression from 12 days to 1 month. Thus, the systems PK/PD model provides a quantitative platform for guiding the engineering and translational development of anti-TFPI recycling antibodies.
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Affiliation(s)
- Dongfen Yuan
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Frederik Rode
- Novo Nordisk, Translational DMPK, H. Lundbeck A/S, Denmark
| | - Yanguang Cao
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Kumar GA, Karmakar J, Mandal C, Chattopadhyay A. Leishmania donovani Internalizes into Host Cells via Caveolin-mediated Endocytosis. Sci Rep 2019; 9:12636. [PMID: 31477757 PMCID: PMC6718660 DOI: 10.1038/s41598-019-49007-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 08/19/2019] [Indexed: 02/08/2023] Open
Abstract
Leishmania donovani is an intracellular protozoan parasite that causes visceral leishmaniasis, a major cause of mortality and morbidity worldwide. The host plasma membrane serves as the portal of entry for Leishmania to gain access to the cellular interior. Although several host cell membrane receptors have been shown to be involved in the entry of Leishmania donovani into host cells, the endocytic pathway involved in the internalization of the parasite is not known. In this work, we explored the endocytic pathway involved in the entry of Leishmania donovani into host macrophages, utilizing specific inhibitors against two major pathways of internalization, i.e., clathrin- and caveolin-mediated endocytosis. We show that pitstop 2, an inhibitor for clathrin-mediated endocytosis, does not affect the entry of Leishmania donovani promastigotes into host macrophages. Interestingly, a significant reduction in internalization was observed upon treatment with genistein, an inhibitor for caveolin-mediated endocytosis. These results are supported by a similar trend in intracellular amastigote load within host macrophages. These results suggest that Leishmania donovani utilizes caveolin-mediated endocytosis to internalize into host cells. Our results provide novel insight into the mechanism of phagocytosis of Leishmania donovani into host cells and assume relevance in the development of novel therapeutics against leishmanial infection.
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Affiliation(s)
- G Aditya Kumar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India
| | - Joyshree Karmakar
- CSIR-Indian Institute of Chemical Biology, Raja S.C. Mullick Road, Kolkata, 700 032, India
| | - Chitra Mandal
- CSIR-Indian Institute of Chemical Biology, Raja S.C. Mullick Road, Kolkata, 700 032, India.
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35
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Computer-assembled cross-species/cross-modalities two-pore physiologically based pharmacokinetic model for biologics in mice and rats. J Pharmacokinet Pharmacodyn 2019; 46:339-359. [PMID: 31079322 DOI: 10.1007/s10928-019-09640-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 05/05/2019] [Indexed: 12/11/2022]
Abstract
Two-pore physiologically-based pharmacokinetic (PBPK) models can be expected to describe the tissue distribution and elimination kinetics of soluble proteins, endogenous or dosed, as function of their size. In this work, we amalgamated our previous two-pore PBPK model for an inert domain antibody (dAb) in mice with the cross-species platform PBPK model for monoclonal antibodies described in literature into a unified two-pore platform that describes protein modalities of different sizes and includes neonatal Fc receptor (FcRn) mediated recycling. This unified PBPK model was parametrized for organ-specific lymph flow rates and the endosomal recycling rate constant using an extended tissue distribution time-course dataset that included an inert dAb, albumin and IgG in rats and mice. The model was evaluated by comparing the ab initio predictions for the tissue distribution and elimination properties of albumin-binding dAbs (AlbudAbsTM) in mice and rats with the experimental observations. Due to the large number of molecular species and reactions involved in large-scale PBPK models, we have also developed and deployed a MatlabTM script for automating the assembly of SimBiologyTM-based two-pore biologics PBPK models which drastically cuts the time and effort required for model building.
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36
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A role for Rab11 in the homeostasis of the endosome-lysosomal pathway. Exp Cell Res 2019; 380:55-68. [PMID: 30981667 DOI: 10.1016/j.yexcr.2019.04.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/31/2019] [Accepted: 04/08/2019] [Indexed: 12/26/2022]
Abstract
The small GTPases Rab11a and 11b are key regulators of membrane transport, localised to the recycling endosomes and also early endosomes. The function of Rab11 within the recycling pathway has been well defined, however, the role of Rab11 at the early endosomes remains poorly characterised. Here, we have generated HeLa cell lines devoid of either Rab11a or Rab11b using CRISPR/Cas9 to functionally dissect the roles of these two Rab11 family members in recycling and in the endosomal-lysosomal system. Both Rab11a and Rab11b contribute to the dynamics of tubulation arising from recycling endosomes whereas Rab11a has the major role in recycling of transferrin receptor. Deletion of either Rab11a or Rab11b resulted in the formation of enlarged early endosomes and perturbation of the endosomal-lysosomal pathway. Strikingly, Rab11a knock-out cells showed an increased density of functional late endosomes/lysosomes as well as lysotracker-positive organelles which were primarily concentrated in a perinuclear location, indicating that the homeostasis of the endosome/lysosome pathway had been perturbed. Moreover, in Rab11a knockout cells there was a functional defect in the intracellular recycling of the cation-independent mannose 6-phosphate receptor (CI-M6PR) between the late endosomes and the TGN, a defect associated with enhanced degradation of CI-M6PR. Expression of wild-type Rab11a in Rab11a knockout cells rescued the late endosome/lysosome phenotype. Overall, these results indicate that Rab11a and Rab11b have overlapping and distinct functions and that Rab11a, unexpectedly, plays a central role in the homeostasis of endosomal-lysosomal biogenesis.
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Kumar GA, Sarkar P, Jafurulla M, Singh SP, Srinivas G, Pande G, Chattopadhyay A. Exploring Endocytosis and Intracellular Trafficking of the Human Serotonin1A Receptor. Biochemistry 2019; 58:2628-2641. [DOI: 10.1021/acs.biochem.9b00033] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- G. Aditya Kumar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Md. Jafurulla
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Shishu Pal Singh
- National Centre for Biological Sciences, UAS-GKVK Campus, Bellary Road, Bangalore 560 065, India
| | - Gunda Srinivas
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Gopal Pande
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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Hardiansyah D, Ng CM. Minimal physiologically-based pharmacokinetic model to investigate the effect of pH dependent FcRn affinity and the endothelial endocytosis on the pharmacokinetics of anti-VEGF humanized IgG1 antibody in cynomolgus monkey. Eur J Pharm Sci 2018; 125:130-141. [PMID: 30248389 DOI: 10.1016/j.ejps.2018.09.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 11/29/2022]
Abstract
In this study, we developed a first minimal physiologically-based pharmacokinetic (mPBPK) model to investigate the complex interaction effects of endocytosis rate/FcRn binding affinity at both acidic/physiological pH on the pharmacokinetics (PK) of the anti-VEGF IgG1 antibodies. The data used in this study were the PK of the native IgG and humanized anti-VEGF IgG1 antibodies with a wide range FcRn-binding at both acidic and physiological pH in the cynomolgus monkey. The basic structure of the developed mPBPK models consisted of plasma, tissue and lymph compartments. The tissue compartment was subdivided into vascular, endothelial and interstitial spaces. Non-equilibrium binding mechanism was used to describe the FcRn-IgG interaction in the endosome. The fittings in the final model with three pH systems in the endosome compartment showed a good fit based on the visualization of the fitted graphs and the coefficient of variations of the estimated parameters (CV < 50%). The quantitative endocytosis/FcRn binding affinity PK relationships was constructed using the final model to provide better understanding of complex interaction effects of endocytosis rate and FcRn binding on PK of anti-VEGF IgG1 antibodies. This result may serve as an important model-based drug discovery platform to guide the design and development of the future generation of anti-VEGF IgG1 or other therapeutic IgG1 antibodies. In addition, the mPBPK model developed in cynomolgus monkey was successfully used to predict the PK of the anti-VEGF IgG1 antibody (bevacizumab) in human subjects.
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Affiliation(s)
- Deni Hardiansyah
- College of Pharmacy, University of Kentucky, BioPharm Building, Room 341, 789 S. Limestone, Lexington, KY 40536, USA
| | - Chee Meng Ng
- College of Pharmacy, University of Kentucky, BioPharm Building, Room 341, 789 S. Limestone, Lexington, KY 40536, USA.
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Li T, Balthasar JP. Application of Physiologically Based Pharmacokinetic Modeling to Predict the Effects of FcRn Inhibitors in Mice, Rats, and Monkeys. J Pharm Sci 2018; 108:701-713. [PMID: 30423340 DOI: 10.1016/j.xphs.2018.10.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/28/2018] [Accepted: 10/30/2018] [Indexed: 01/06/2023]
Abstract
There is a growing interest in developing inhibitors of the neonatal Fc-receptor, FcRn, for use in the treatment for humoral autoimmune conditions. We have developed a new physiologically based pharmacokinetic model that is capable of characterizing the pharmacokinetics and pharmacodynamics of anti-FcRn monoclonal antibodies (mAb) in mice, rats, and monkeys. The model includes incorporation of FcRn recycling of immune gamma globulin (IgG) in hematopoietic cells in addition to FcRn recycling of IgG in vascular endothelial cells and considers FcRn turnover and intracellular cycling. The model captured antibody disposition in wild-type and FcRn-knockout mice and rats, and also predicted the effects of intravenous immune globulin and anti-FcRn mAb on IgG disposition. Simulations predicted the change in IgG clearance in response to intravenous immune globulin with good accuracy in rats (mean prediction error of 7.15% ± 7.67%). In monkeys, prediction windows for simulated IgG concentration versus time data, as generated through Monte Carlo simulation, were able to capture the effects of anti-FcRn mAb on endogenous IgG. The model may have utility in guiding preclinical evaluations of anti-FcRn therapies in development, potentially assisting in the identification of optimal dosing strategies for this emerging class of immunosuppressive drugs.
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Affiliation(s)
- Tommy Li
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14214
| | - Joseph P Balthasar
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14214.
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40
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Cullen PJ, Steinberg F. To degrade or not to degrade: mechanisms and significance of endocytic recycling. Nat Rev Mol Cell Biol 2018; 19:679-696. [PMID: 30194414 DOI: 10.1038/s41580-018-0053-7] [Citation(s) in RCA: 329] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Newly endocytosed integral cell surface proteins are typically either directed for degradation or subjected to recycling back to the plasma membrane. The sorting of integral cell surface proteins, including signalling receptors, nutrient transporters, ion channels, adhesion molecules and polarity markers, within the endolysosomal network for recycling is increasingly recognized as an essential feature in regulating the complexities of physiology at the cell, tissue and organism levels. Historically, endocytic recycling has been regarded as a relatively passive process, where the majority of internalized integral proteins are recycled via a nonspecific sequence-independent 'bulk membrane flow' pathway. Recent work has increasingly challenged this view. The discovery of sequence-specific sorting motifs and the identification of cargo adaptors and associated coat complexes have begun to uncover the highly orchestrated nature of endosomal cargo recycling, thereby providing new insight into the function and (patho)physiology of this process.
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Affiliation(s)
- Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol, UK.
| | - Florian Steinberg
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg im Breisgau, Germany.
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41
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Polli JR, Engler FA, Balthasar JP. Physiologically Based Modeling of the Pharmacokinetics of "Catch-and-Release" Anti-Carcinoembryonic Antigen Monoclonal Antibodies in Colorectal Cancer Xenograft Mouse Models. J Pharm Sci 2018; 108:674-691. [PMID: 30321546 DOI: 10.1016/j.xphs.2018.09.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
Abstract
Engineered monoclonal antibodies (mAbs) with pH-sensitive target release, or "catch-and-release" (CAR) binding, have shown promise in decreasing the extent of target-mediated mAb elimination, increasing mAb exposure, and increasing dose potency. This study developed a mechanistic physiologically based pharmacokinetic (PBPK) model to evaluate the effects of pH-sensitive CAR target binding on the disposition of anti-carcinoembryonic antigen (CEA) mAbs in mouse models of colorectal cancer. The PBPK model was qualified by comparing model-predicted plasma concentration-time data with data observed in tumor-bearing mice following the administration of T84.66, a "standard" anti-CEA mAb that demonstrates strong binding at pH 7.4 and 5.5. Further simulations evaluated the effects CAR pH-dependent binding, with decreasing CEA affinity with decreasing pH, on anti-CEA mAb plasma pharmacokinetics. Simulated data were compared with data observed for a novel CAR mAb, 10H6. The PBPK model provided precise parameter estimates, and excellent data characterization (median prediction error 18.4%) following fitting to T84.66 data. Simulations well predicted 10H6 data (median prediction error 21.4%). Sensitivity analyses demonstrated that key determinants of the disposition of CAR mAbs include the following: antigen binding affinity, the rate constant of mAb-CEA dissociation in acidified endosomes, antigen concentration, and the tumor vasculature reflection coefficient.
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Affiliation(s)
- Joseph Ryan Polli
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14215
| | - Frank A Engler
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14215
| | - Joseph P Balthasar
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York 14215.
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42
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Maib H, Ferreira F, Vassilopoulos S, Smythe E. Cargo regulates clathrin-coated pit invagination via clathrin light chain phosphorylation. J Cell Biol 2018; 217:4253-4266. [PMID: 30228161 PMCID: PMC6279376 DOI: 10.1083/jcb.201805005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 07/20/2018] [Accepted: 09/07/2018] [Indexed: 12/18/2022] Open
Abstract
Phosphorylation of clathrin light chains (CLCs) regulates GPCR uptake but is dispensable for transferrin internalization. Maib et al. show that CLCb phosphorylation is required for efficient auxilin-mediated clathrin exchange to promote coated pit invagination in a cargo-specific manner. Clathrin light chains (CLCs) control selective uptake of a range of G protein–coupled receptors (GPCRs), although the mechanism by which this occurs has remained elusive thus far. In particular, site-specific phosphorylation of CLCb controls the uptake of the purinergic GPCR P2Y12, but it is dispensable for the constitutive uptake of the transferrin receptor (TfR). We demonstrate that phosphorylation of CLCb is required for the maturation of clathrin-coated pits (CCPs) through the transition of flat lattices into invaginated buds. This transition is dependent on efficient clathrin exchange regulated by CLCb phosphorylation and mediated through auxilin. Strikingly, this rearrangement is required for the uptake of P2Y12 but not TfR. These findings link auxilin-mediated clathrin exchange to early stages of CCP invagination in a cargo-specific manner. This supports a model in which CCPs invaginate with variable modes of curvature depending on the cargo they incorporate.
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Affiliation(s)
- Hannes Maib
- Centre for Membrane Interactions and Dynamics, Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Filipe Ferreira
- Centre for Membrane Interactions and Dynamics, Department of Biomedical Science, University of Sheffield, Sheffield, UK
| | - Stéphane Vassilopoulos
- Sorbonne Université, INSERM, Institute of Myology, Centre for Research in Myology, UMRS 974, Paris, France
| | - Elizabeth Smythe
- Centre for Membrane Interactions and Dynamics, Department of Biomedical Science, University of Sheffield, Sheffield, UK
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43
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Maas BM, Cao Y. A minimal physiologically based pharmacokinetic model to investigate FcRn-mediated monoclonal antibody salvage: Effects of K on, K off, endosome trafficking, and animal species. MAbs 2018; 10:1322-1331. [PMID: 30130450 DOI: 10.1080/19420862.2018.1506648] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Manipulation of binding affinity between monoclonal antibodies (mAbs) and the neonatal Fc receptor (FcRn) has been leveraged to extend mAb half-life; however, the steps required for success remain ambiguous and experimental observations are inconsistent. Recent models have considered the time course of endosomal transit a major contributor to the relationship between FcRn affinity and antibody half-life. Our objective was to develop a minimal physiologically based pharmacokinetic model to explain how changes in IgG-FcRn association rate constant (Kon), dissociation rate constant (Koff), and endosomal transit time [T(w)] translate to improved IgG clearance across mice, monkeys and humans. By simulating mAb clearance across physiological values of Kon, Koff, and T(w), we found that lowering Koff improves clearance only until the dissociation half-life reaches endosomal transit time. In contrast, Kon influenced clearance independently of T(w).The model was then applied to fit 66 mAb plasma profiles across species digitized from the literature, and clearance of mAb (CLIgG) and vascular fluid-phase endocytosis rate (CLup) were estimated. We found that CLIgG scaled well with body weight (allometric exponent of 0.90). After accounting for mAbs with significant FcRn binding at physiological pH, CLup was allometrically scalable (exponent 0.72). For the antibodies surveyed, Kon was more highly correlated with CLIgG across all species. The relationship between Koff and KD with CLIgG was largely inconsistent. Taken together, this model provides a parsimonious approach to evaluate endosomal transit kinetics using only mAb plasma concentrations. These findings reinforce the idea that endosomal transit kinetics should be considered when modeling FcRn salvage.
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Affiliation(s)
- Brian M Maas
- a Division of Pharmacotherapy and Experimental Therapeutics , UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill , Chapel Hill , USA
| | - Yanguang Cao
- a Division of Pharmacotherapy and Experimental Therapeutics , UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill , Chapel Hill , USA
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44
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Xu X, Liu Y, Tang M, Yan Y, Gu W, Wang W, Meng Q. The function of Eriocheir sinensis transferrin and iron in Spiroplasma eriocheiris infection. FISH & SHELLFISH IMMUNOLOGY 2018; 79:79-85. [PMID: 29753143 DOI: 10.1016/j.fsi.2018.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 05/05/2018] [Accepted: 05/08/2018] [Indexed: 06/08/2023]
Abstract
Transferrin, a member of the iron binding superfamily protein, plays an extremely important role in the transport of iron in the biological process of cells. The result of preliminary proteomic study on E. sinensis hemocytes infected Spiroplasma eriocheiris showed the expression of transferrin (EsTF) and ferrin (EsFe) significantly changed. In addition, other reports have confirmed that transferrin, ferritin and iron are involved in the immune response of hosts. In order to validate the immune function of EsTF, the whole length of EsTF was successfully amplified by the gene cloning and RACE technique. The results showed that the full-length cDNA of the EsTF gene was 2748 bp, including a 2193 bp open reading frame which encodes 730 amino acids. The result of bioinformatics analysis showed EsTF contains two highly conserved TR_FER domains. Evolutionary analysis showed that EsTF has a close genetic relationship with other TFs of invertebrates. In addition, EsTF mRNA was highly transcripted in nerve and intestine tissues, followed by hemocytes. The expression of EsTF, EsFe1 and EsFe2 increased after exogenous supplemental of iron under the concentration of 100 nmol/L in water. After exogenous supplement of iron and injection with S. eriocheiris, these three gene transcription of mRNA levels were higher than that of PBS group, while lower than the S. eriocheiris group and the iron group. Besides, the copy number of S. eriocheiris in the experimental group was significantly reduced, and the death rate decreased. As can be seen, iron made transferrin and ferritin return to normal levels during the infection of S. eriocheiris and help the host maintain normal immunity levels to resist S. eriocheiris. These results further demonstrated that EsTF, EsFe1, EsFe2 and iron play a role in the immune defense mechanism of the crabs to resist S. eriocheiris infection.
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Affiliation(s)
- Xuechuan Xu
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Yuhan Liu
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Mengyue Tang
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Yuye Yan
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Wei Gu
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China; Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, Jiangsu, 222005, China
| | - Wen Wang
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China
| | - Qingguo Meng
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023, China; Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, Jiangsu, 222005, China.
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45
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Allgood SC, Neunuebel MR. The recycling endosome and bacterial pathogens. Cell Microbiol 2018; 20:e12857. [PMID: 29748997 PMCID: PMC5993623 DOI: 10.1111/cmi.12857] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 04/05/2018] [Accepted: 04/27/2018] [Indexed: 12/29/2022]
Abstract
Bacterial pathogens have developed a wide range of strategies to survive within human cells. A number of pathogens multiply in a vacuolar compartment, whereas others can rupture the vacuole and replicate in the host cytosol. A common theme among many bacterial pathogens is the use of specialised secretion systems to deliver effector proteins into the host cell. These effectors can manipulate the host's membrane trafficking pathways to remodel the vacuole into a replication-permissive niche and prevent degradation. As master regulators of eukaryotic membrane traffic, Rab GTPases are principal targets of bacterial effectors. This review highlights the manipulation of Rab GTPases that regulate host recycling endocytosis by several bacterial pathogens, including Chlamydia pneumoniae, Chlamydia trachomatis, Shigella flexneri, Salmonella enterica serovar Typhimurium, Uropathogenic Escherichia coli, and Legionella pneumophila. Recycling endocytosis plays key roles in a variety of cellular aspects such as nutrient uptake, immunity, cell division, migration, and adhesion. Though much remains to be understood about the molecular basis and the biological relevance of bacterial pathogens exploiting Rab GTPases, current knowledge supports the notion that endocytic recycling Rab GTPases are differentially targeted to avoid degradation and support bacterial replication. Thus, future studies of the interactions between bacterial pathogens and host endocytic recycling pathways are poised to deepen our understanding of bacterial survival strategies.
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Affiliation(s)
| | - M. Ramona Neunuebel
- Department of Biological Sciences, University of Delaware, Newark, Delaware, USA
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46
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Fermie J, Liv N, Ten Brink C, van Donselaar EG, Müller WH, Schieber NL, Schwab Y, Gerritsen HC, Klumperman J. Single organelle dynamics linked to 3D structure by correlative live-cell imaging and 3D electron microscopy. Traffic 2018; 19:354-369. [PMID: 29451726 DOI: 10.1111/tra.12557] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 01/05/2023]
Abstract
Live-cell correlative light-electron microscopy (live-cell-CLEM) integrates live movies with the corresponding electron microscopy (EM) image, but a major challenge is to relate the dynamic characteristics of single organelles to their 3-dimensional (3D) ultrastructure. Here, we introduce focused ion beam scanning electron microscopy (FIB-SEM) in a modular live-cell-CLEM pipeline for a single organelle CLEM. We transfected cells with lysosomal-associated membrane protein 1-green fluorescent protein (LAMP-1-GFP), analyzed the dynamics of individual GFP-positive spots, and correlated these to their corresponding fine-architecture and immediate cellular environment. By FIB-SEM we quantitatively assessed morphological characteristics, like number of intraluminal vesicles and contact sites with endoplasmic reticulum and mitochondria. Hence, we present a novel way to integrate multiple parameters of subcellular dynamics and architecture onto a single organelle, which is relevant to address biological questions related to membrane trafficking, organelle biogenesis and positioning. Furthermore, by using CLEM to select regions of interest, our method allows for targeted FIB-SEM, which significantly reduces time required for image acquisition and data processing.
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Affiliation(s)
- Job Fermie
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Section Molecular Biophysics, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, The Netherlands
| | - Nalan Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Corlinda Ten Brink
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Elly G van Donselaar
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Wally H Müller
- Section Cryo-EM, Department of Chemistry, Utrecht University, Utrecht, The Netherlands
| | - Nicole L Schieber
- Electron Microscopy Core Facility, EMBL Heidelberg, Heidelberg, Germany
| | - Yannick Schwab
- Electron Microscopy Core Facility, EMBL Heidelberg, Heidelberg, Germany
| | - Hans C Gerritsen
- Section Molecular Biophysics, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, The Netherlands
| | - Judith Klumperman
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
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47
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Sorkina T, Ma S, Larsen MB, Watkins SC, Sorkin A. Small molecule induced oligomerization, clustering and clathrin-independent endocytosis of the dopamine transporter. eLife 2018; 7:32293. [PMID: 29630493 PMCID: PMC5896956 DOI: 10.7554/elife.32293] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 03/22/2018] [Indexed: 12/14/2022] Open
Abstract
Clathrin-independent endocytosis (CIE) mediates internalization of many transmembrane proteins but the mechanisms of cargo recruitment during CIE are poorly understood. We found that the cell-permeable furopyrimidine AIM-100 promotes dramatic oligomerization, clustering and CIE of human and mouse dopamine transporters (DAT), but not of their close homologues, norepinephrine and serotonin transporters. All effects of AIM-100 on DAT and the occupancy of substrate binding sites in the transporter were mutually exclusive, suggesting that AIM-100 may act by binding to DAT. Surprisingly, AIM-100-induced DAT endocytosis was independent of dynamin, cholesterol-rich microdomains and actin cytoskeleton, implying that a novel endocytic mechanism is involved. AIM-100 stimulated trafficking of internalized DAT was also unusual: DAT accumulated in early endosomes without significant recycling or degradation. We propose that AIM-100 augments DAT oligomerization through an allosteric mechanism associated with the DAT conformational state, and that oligomerization-triggered clustering leads to a coat-independent endocytosis and subsequent endosomal retention of DAT.
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Affiliation(s)
- Tatiana Sorkina
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Shiqi Ma
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Mads Breum Larsen
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Alexander Sorkin
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
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48
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Mygind KJ, Störiko T, Freiberg ML, Samsøe-Petersen J, Schwarz J, Andersen OM, Kveiborg M. Sorting nexin 9 (SNX9) regulates levels of the transmembrane ADAM9 at the cell surface. J Biol Chem 2018; 293:8077-8088. [PMID: 29622675 DOI: 10.1074/jbc.ra117.001077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/12/2018] [Indexed: 11/06/2022] Open
Abstract
ADAM9 is an active member of the family of transmembrane ADAMs (a disintegrin and metalloproteases). It plays a role in processes such as bone formation and retinal neovascularization, and importantly, its expression in human cancers correlates with disease stage and poor prognosis. Functionally, ADAM9 can cleave several transmembrane proteins, thereby shedding their ectodomains from the cell surface. Moreover, ADAM9 regulates cell behavior by binding cell-surface receptors such as integrin and membrane-type matrix metalloproteases. Because these functions are mainly restricted to the cell surface, understanding the mechanisms regulating ADAM9 localization and activity at this site is highly important. To this end, we here investigated how intracellular trafficking regulates ADAM9 availability at the cell surface. We found that ADAM9 undergoes constitutive clathrin-dependent internalization and subsequent degradation or recycling to the plasma membrane. We confirmed previous findings of an interaction between ADAM9 and the intracellular sorting protein, sorting nexin 9 (SNX9), as well as its close homolog SNX18. Knockdown of either SNX9 or SNX18 had no apparent effects on ADAM9 internalization or recycling. However, double knockdown of SNX9 and SNX18 decreased ADAM9 internalization significantly, demonstrating a redundant role in this process. Moreover, SNX9 knockdown revealed a nonredundant effect on overall ADAM9 protein levels, resulting in increased ADAM9 levels at the cell surface, and a corresponding increase in the shedding of Ephrin receptor B4, a well-known ADAM9 substrate. Together, our findings demonstrate that intracellular SNX9-mediated trafficking constitutes an important ADAM9 regulatory pathway.
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Affiliation(s)
- Kasper J Mygind
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Theresa Störiko
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Marie L Freiberg
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Jacob Samsøe-Petersen
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Jeanette Schwarz
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Olav M Andersen
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience DANDRITE-Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Ole Worms Alle 3, 8000 Aarhus C, Denmark
| | - Marie Kveiborg
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark.
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49
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Yuan D, Rode F, Cao Y. A Minimal Physiologically Based Pharmacokinetic Model with a Nested Endosome Compartment for Novel Engineered Antibodies. AAPS JOURNAL 2018. [PMID: 29541870 DOI: 10.1208/s12248-017-0183-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We proposed here a minimal physiologically based pharmacokinetic (mPBPK) model for a group of novel engineered antibodies in mice and humans. These antibodies are designed with altered binding properties of their Fc domain with neonatal Fc receptor (FcRn) or the Fab domain with their cognate targets (recycling antibodies) in acidic endosomes. To enable simulations of such binding features in the change of antibody pharmacokinetics and its target suppression, we nested an endothelial endosome compartment in parallel with plasma compartment based on our previously established mPBPK model. The fluid-phase pinocytosis rate from plasma to endothelial endosomes was reflected by the clearance of antibodies in FcRn dysfunctional humans or FcRn-knockout mice. The endosomal recycling rate of FcRn-bound antibodies was calculated based on the reported endosomal transit time. The nonspecific catabolism in endosomes was fitted using pharmacokinetic data of a human wild-type IgG1 adalimumab in humans and B21M in human FcRn (hFcRn) transgenic mice. The developed model adequately predicted the pharmacokinetics of infliximab, motavizumab, and an Fc variant of motavizumab in humans and the pharmacokinetics of bevacizumab, an Fc variant of bevacizumab, and a recycling antibody PH-IgG1 and its non-pH dependent counterpart NPH-IgG1 in hFcRn transgenic mice. Our proposed model provides a platform for evaluation of the pharmacokinetics and disposition behaviors of Fc-engineered antibodies and recycling antibodies.
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Affiliation(s)
- Dongfen Yuan
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 301 Pharmacy Lane, Chapel Hill, North Carolina, 27599, USA
| | | | - Yanguang Cao
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 301 Pharmacy Lane, Chapel Hill, North Carolina, 27599, USA. .,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, USA.
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50
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Hammerling BC, Shires SE, Leon LJ, Cortez MQ, Gustafsson ÅB. Isolation of Rab5-positive endosomes reveals a new mitochondrial degradation pathway utilized by BNIP3 and Parkin. Small GTPases 2017; 11:69-76. [PMID: 28696827 DOI: 10.1080/21541248.2017.1342749] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Degradation of mitochondria is an important cellular quality control mechanism mediated by two distinct pathways: one involving Parkin-mediated ubiquitination and the other dependent on mitophagy receptors. It is known that mitochondria are degraded by the autophagy pathway; however, we recently reported that the small GTPase Rab5 and early endosomes also participate in Parkin-mediated mitochondrial clearance. Here, we have developed a protocol to isolate Rab5-positive vesicles from cells for proteomics analysis and provide additional data confirming that mitophagy regulators and mitochondrial proteins are present in these vesicles. We also demonstrate that the mitophagy receptor BNIP3 utilizes the Rab5-endosomal pathway to clear mitochondria in cells. These findings indicate that a redundancy exists in the downstream degradation pathways to ensure efficient mitochondrial clearance.
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Affiliation(s)
- Babette C Hammerling
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Sarah E Shires
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Leonardo J Leon
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Melissa Q Cortez
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Åsa B Gustafsson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
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