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Zhang B, Chuang GY, Biju A, Biner D, Cheng J, Wang Y, Bao S, Chao CW, Lei H, Liu T, Nazzari AF, Yang Y, Zhou T, Chen SJ, Chen X, Kong WP, Ou L, Parchment DK, Sarfo EK, SiMa H, Todd JP, Wang S, Woodward RA, Cheng C, Rawi R, Mascola JR, Kwong PD. Cholesterol reduction by immunization with a PCSK9 mimic. Cell Rep 2024; 43:114285. [PMID: 38819987 PMCID: PMC11305080 DOI: 10.1016/j.celrep.2024.114285] [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: 10/20/2023] [Revised: 04/22/2024] [Accepted: 05/13/2024] [Indexed: 06/02/2024] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a plasma protein that controls cholesterol homeostasis. Here, we design a human PCSK9 mimic, named HIT01, with no consecutive 9-residue stretch in common with any human protein as a potential heart attack vaccine. Murine immunizations with HIT01 reduce low-density lipoprotein (LDL) and cholesterol levels by 40% and 30%, respectively. Immunization of cynomolgus macaques with HIT01-K21Q-R218E, a cleavage-resistant variant, elicits high-titer PCSK9-directed antibody responses and significantly reduces serum levels of cholesterol 2 weeks after each immunization. However, HIT01-K21Q-R218E immunizations also increase serum PCSK9 levels by up to 5-fold, likely due to PCSK9-binding antibodies altering the half-life of PCSK9. While vaccination with a PCSK9 mimic can induce antibodies that block interactions of PCSK9 with the LDL receptor, PCSK9-binding antibodies appear to alter homeostatic levels of PCSK9, thereby confounding its vaccine impact. Our results nevertheless suggest a mechanism for increasing the half-life of soluble regulatory factors by vaccination.
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Affiliation(s)
- Baoshan Zhang
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Gwo-Yu Chuang
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Andrea Biju
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel Biner
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jiaxuan Cheng
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yiran Wang
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Saran Bao
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cara W Chao
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Haotian Lei
- Research Technologies Branch, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tracy Liu
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alexandra F Nazzari
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yongping Yang
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tongqing Zhou
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Steven J Chen
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xuejun Chen
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wing-Pui Kong
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Li Ou
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Danealle K Parchment
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Edward K Sarfo
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - HaoMin SiMa
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - John-Paul Todd
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shuishu Wang
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ruth A Woodward
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cheng Cheng
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Reda Rawi
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - John R Mascola
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter D Kwong
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892, USA; Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA.
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Galvão Lopes V, Fernandes de Oliveira V, Mendonça Munhoz Dati L, Naslavsky MS, Ferreira GM, Hirata MH. Dynamics of the personalities of PCSK9 on missense variants (rs505151 and rs562556) from elderly cohort studies in Brazil. J Biomol Struct Dyn 2023; 41:15625-15633. [PMID: 37010997 DOI: 10.1080/07391102.2023.2191140] [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: 12/13/2022] [Accepted: 03/06/2023] [Indexed: 04/04/2023]
Abstract
The Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) promotes the degradation of the low-density lipoprotein receptors (LDLR). Gain-of-function (GOF) variants of PCSK9 significantly affects lipid metabolism leading to coronary artery disease (CAD), owing to the raising the plasma low-density lipoprotein (LDL). Considering the public health matter, large-scale genomic studies have been conducted worldwide to provide the genetic architecture of populations for the implementation of precision medicine actions. Nevertheless, despite the advances in genomic studies, non-European populations are still underrepresented in public genomic data banks. Despite this, we found two high-frequency variants (rs505151 and rs562556) in the ABraOM databank (Brazilian genomic variants) from a cohort SABE study conducted in the largest city of Brazil, São Paulo. Here, we assessed the structural and dynamical features of these variants against WT through a molecular dynamics study. We sought fundamental dynamical interdomain relations through Perturb Response Scanning (PRS) and we found an interesting change of dynamical relation between prodomain and Cysteine-Histidine-Rich-Domain (CHRD) in the variants. The results highlight the pivotal role of prodomain in the PCSK9 dynamic and the implications for the development of new drugs depending on patient group genotype.
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Affiliation(s)
- Vitor Galvão Lopes
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Victor Fernandes de Oliveira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Livia Mendonça Munhoz Dati
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Michel Satya Naslavsky
- Human Genome and Stem Cell Research Center (HUG-CELL), Biosciences Institute, University of Sao Paulo, São Paulo, Brazil
| | - Glaucio Monteiro Ferreira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Mario Hiroyuki Hirata
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil
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3
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Fruchart Gaillard C, Ouadda ABD, Ciccone L, Girard E, Mikaeeli S, Evagelidis A, Le Dévéhat M, Susan-Resiga D, Lajeunesse EC, Nozach H, Ramos OHP, Thureau A, Legrand P, Prat A, Dive V, Seidah NG. Molecular interactions of PCSK9 with an inhibitory nanobody, CAP1 and HLA-C: Functional regulation of LDLR levels. Mol Metab 2022; 67:101662. [PMID: 36566984 PMCID: PMC9816786 DOI: 10.1016/j.molmet.2022.101662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE The liver-derived circulating PCSK9 enhances the degradation of the LDL receptor (LDLR) in endosomes/lysosomes. PCSK9 inhibition or silencing is presently used in clinics worldwide to reduce LDL-cholesterol, resulting in lower incidence of cardiovascular disease and possibly cancer/metastasis. The mechanism by which the PCSK9-LDLR complex is sorted to degradation compartments is not fully understood. We previously suggested that out of the three M1, M2 and M3 subdomains of the C-terminal Cys/His-rich-domain (CHRD) of PCSK9, only M2 is critical for the activity of extracellular of PCSK9 on cell surface LDLR. This likely implicates the binding of M2 to an unknown membrane-associated "protein X" that would escort the complex to endosomes/lysosomes for degradation. We reported that a nanobody P1.40 binds the M1 and M3 domains of the CHRD and inhibits the function of PCSK9. It was also reported that the cytosolic adenylyl cyclase-associated protein 1 (CAP1) could bind M1 and M3 subdomains and enhance the activity of PCSK9. In this study, we determined the 3-dimensional structure of the CHRD-P1.40 complex to understand the intricate interplay between P1.40, CAP1 and PCSK9 and how they regulate LDLR degradation. METHODS X-ray diffraction of the CHRD-P1.40 complex was analyzed with a 2.2 Å resolution. The affinity and interaction of PCSK9 or CHRD with P1.40 or CAP1 was analyzed by atomic modeling, site-directed mutagenesis, bio-layer interferometry, expression in hepatic cell lines and immunocytochemistry to monitor LDLR degradation. The CHRD-P1.40 interaction was further analyzed by deep mutational scanning and binding assays to validate the role of predicted critical residues. Conformational changes and atomic models were obtained by small angle X-ray scattering (SAXS). RESULTS We demonstrate that PCSK9 exists in a closed or open conformation and that P1.40 favors the latter by binding key residues in the M1 and M3 subdomains of the CHRD. Our data show that CAP1 is well secreted by hepatic cells and binds extracellular PCSK9 at distinct residues in the M1 and M3 modules and in the acidic prodomain. CAP1 stabilizes the closed conformation of PCSK9 and prevents P1.40 binding. However, CAP1 siRNA only partially inhibited PCSK9 activity on the LDLR. By modeling the previously reported interaction between M2 and an R-X-E motif in HLA-C, we identified Glu567 and Arg549 as critical M2 residues binding HLA-C. Amazingly, these two residues are also required for the PCSK9-induced LDLR degradation. CONCLUSIONS The present study reveals that CAP1 enhances the function of PCSK9, likely by twisting the protein into a closed configuration that exposes the M2 subdomain needed for targeting the PCSK9-LDLR complex to degradation compartments. We hypothesize that "protein X", which is expected to guide the LDLR-PCSK9-CAP1 complex to these compartments after endocytosis into clathrin-coated vesicles, is HLA-C or a similar MHC-I family member. This conclusion is supported by the PCSK9 natural loss-of-function Q554E and gain-of-function H553R M2 variants, whose consequences are anticipated by our modeling.
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Affiliation(s)
- Carole Fruchart Gaillard
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France
| | - Ali Ben Djoudi Ouadda
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Lidia Ciccone
- Synchrotron SOLEIL, HelioBio group, l'Orme des Merisiers, 91190 Saint-Aubin, France; Department of Pharmacy, University of Pisa, Via Bonanno, 6, 56126 Pisa, Italy
| | - Emmanuelle Girard
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Sepideh Mikaeeli
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Alexandra Evagelidis
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Maïlys Le Dévéhat
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Delia Susan-Resiga
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Evelyne Cassar Lajeunesse
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France
| | - Hervé Nozach
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France
| | - Oscar Henrique Pereira Ramos
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France
| | - Aurélien Thureau
- Synchrotron SOLEIL, HelioBio group, l'Orme des Merisiers, 91190 Saint-Aubin, France
| | - Pierre Legrand
- Synchrotron SOLEIL, HelioBio group, l'Orme des Merisiers, 91190 Saint-Aubin, France
| | - Annik Prat
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Vincent Dive
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, France
| | - Nabil G Seidah
- Montreal Clinical Research Institute (IRCM), affiliated to the University of Montreal, Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada.
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Abstract
This article reviews the discovery of PCSK9, its structure-function characteristics, and its presently known and proposed novel biological functions. The major critical function of PCSK9 deduced from human and mouse studies, as well as cellular and structural analyses, is its role in increasing the levels of circulating low-density lipoprotein (LDL)-cholesterol (LDLc), via its ability to enhance the sorting and escort of the cell surface LDL receptor (LDLR) to lysosomes. This implicates the binding of the catalytic domain of PCSK9 to the EGF-A domain of the LDLR. This also requires the presence of the C-terminal Cys/His-rich domain, its binding to the secreted cytosolic cyclase associated protein 1, and possibly another membrane-bound "protein X". Curiously, in PCSK9-deficient mice, an alternative to the downregulation of the surface levels of the LDLR by PCSK9 is taking place in the liver of female mice in a 17β-estradiol-dependent manner by still an unknown mechanism. Recent studies have extended our understanding of the biological functions of PCSK9, namely its implication in septic shock, vascular inflammation, viral infections (Dengue; SARS-CoV-2) or immune checkpoint modulation in cancer via the regulation of the cell surface levels of the T-cell receptor and MHC-I, which govern the antitumoral activity of CD8+ T cells. Because PCSK9 inhibition may be advantageous in these processes, the availability of injectable safe PCSK9 inhibitors that reduces by 50% to 60% LDLc above the effect of statins is highly valuable. Indeed, injectable PCSK9 monoclonal antibody or small interfering RNA could be added to current immunotherapies in cancer/metastasis.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), Montreal, QC, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), Montreal, QC, Canada
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5
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Seidah NG. The PCSK9 discovery, an inactive protease with varied functions in hypercholesterolemia, viral infections, and cancer. J Lipid Res 2021; 62:100130. [PMID: 34606887 PMCID: PMC8551645 DOI: 10.1016/j.jlr.2021.100130] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/19/2021] [Accepted: 08/21/2021] [Indexed: 01/06/2023] Open
Abstract
In 2003, the sequences of mammalian proprotein convertase subtilisin/kexin type 9 (PCSK9) were reported. Radiolabeling pulse-chase analyses demonstrated that PCSK9 was synthesized as a precursor (proPCSK9) that undergoes autocatalytic cleavage in the endoplasmic reticulum into PCSK9, which is then secreted as an inactive enzyme in complex with its inhibitory prodomain. Its high mRNA expression in liver hepatocytes and its gene localization on chromosome 1p32, a third locus associated with familial hypercholesterolemia, other than LDLR or APOB, led us to identify three patient families expressing the PCSK9 variants S127R or F216L. Although Pcsk9 and Ldlr were downregulated in mice that were fed a cholesterol-rich diet, PCSK9 overexpression led to the degradation of the LDLR. This led to the demonstration that gain-of-function and loss-of-function variations in PCSK9 modulate its bioactivity, whereby PCSK9 binds the LDLR in a nonenzymatic fashion to induce its degradation in endosomes/lysosomes. PCSK9 was also shown to play major roles in targeting other receptors for degradation, thereby regulating various processes, including hypercholesterolemia and associated atherosclerosis, vascular inflammation, viral infections, and immune checkpoint regulation in cancer. Injectable PCSK9 monoclonal antibody or siRNA is currently used in clinics worldwide to treat hypercholesterolemia and could be combined with current therapies in cancer/metastasis. In this review, we present the critical information that led to the discovery of PCSK9 and its implication in LDL-C metabolism. We further analyze the underlying functional mechanism(s) in the regulation of LDL-C, as well as the evolving novel roles of PCSK9 in both health and disease states.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM, affiliated to the University of Montreal), 110 Pine Ave West, Montreal, QC, H2W 1R7, Canada.
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6
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Development of a novel, fully human, anti-PCSK9 antibody with potent hypolipidemic activity by utilizing phage display-based strategy. EBioMedicine 2021; 65:103250. [PMID: 33647772 PMCID: PMC7921758 DOI: 10.1016/j.ebiom.2021.103250] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/27/2021] [Accepted: 02/03/2021] [Indexed: 12/19/2022] Open
Abstract
Background Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates serum LDL cholesterol (LDL-C) levels by facilitating the degradation of the LDL receptor (LDLR) and is an attractive therapeutic target for hypercholesterolemia intervention. Herein, we generated a novel fully human antibody with favourable druggability by utilizing phage display-based strategy. Methods A potent single-chain variable fragment (scFv) named AP2M21 was obtained by screening a fully human scFv phage display library with hPCSK9, and performing two in vitro affinity maturation processes including CDR-targeted tailored mutagenesis and cross-cloning. Thereafter, it was transformed to a full-length Fc-silenced anti-PCSK9 antibody FAP2M21 by fusing to a modified human IgG1 Fc fragment with L234A/L235A/N297G mutations and C-terminal lysine deletion, thus eliminating its immune effector functions and mitigating mAb heterogeneity. Findings Our data showed that the generated full-length anti-PCSK9 antibody FAP2M21 binds to hPCSK9 with a KD as low as 1.42 nM, and a dramatically slow dissociation rate (koff, 4.68 × 10−6 s−1), which could be attributed to its lower binding energy (-47.51 kcal/mol) than its parent counterpart FAP2 (-30.39 kcal/mol). We verified that FAP2M21 potently inhibited PCSK9-induced reduction of LDL-C uptake in HepG2 cells, with an EC50 of 43.56 nM. Further, in hPCSK9 overexpressed C57BL/6 mice, a single tail i.v. injection of FAP2M21 at 1, 3 and 10 mg/kg, dose-dependently up-regulated hepatic LDLR levels, and concomitantly reduced serum LDL-C by 3.3% (P = 0.658, unpaired Student's t-test), 30.2% (P = 0.002, Mann-Whitney U-test) and 37.2% (P = 0.002, Mann-Whitney U-test), respectively. Interpretation FAP2M21 with potent inhibitory effect on PCSK9 may serve as a promising therapeutic agent for treating hypercholesterolemia and associated cardiovascular diseases.
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7
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Hsiao YC, Chen YJJ, Goldstein LD, Wu J, Lin Z, Schneider K, Chaudhuri S, Antony A, Bajaj Pahuja K, Modrusan Z, Seshasayee D, Seshagiri S, Hötzel I. Restricted epitope specificity determined by variable region germline segment pairing in rodent antibody repertoires. MAbs 2021; 12:1722541. [PMID: 32041466 PMCID: PMC7039645 DOI: 10.1080/19420862.2020.1722541] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Antibodies from B-cell clonal lineages share sequence and structural properties as well as epitope specificity. Clonally unrelated antibodies can similarly share sequence and specificity properties and are said to be convergent. Convergent antibody responses against several antigens have been described in humans and mice and include different classes of shared sequence features. In particular, some antigens and epitopes can induce convergent responses of clonally unrelated antibodies with restricted heavy (VH) and light (VL) chain variable region germline segment usage without similarity in the heavy chain third complementarity-determining region (CDR H3), a critical specificity determinant. Whether these V germline segment-restricted responses reflect a general epitope specificity restriction of antibodies with shared VH/VL pairing is not known. Here, we investigated this question by determining patterns of antigen binding competition between clonally unrelated antigen-specific rat antibodies from paired-chain deep sequencing datasets selected based solely on VH/VL pairing. We found that antibodies with shared VH/VL germline segment pairings but divergent CDR H3 sequences almost invariably have restricted epitope specificity indicated by shared binding competition patterns. This epitope restriction included 82 of 85 clonally unrelated antibodies with 13 different VH/VL pairings binding in 8 epitope groups in 2 antigens. The corollary that antibodies with shared VH/VL pairing and epitope-restricted binding can accommodate widely divergent CDR H3 sequences was confirmed by in vitro selection of variants of anti-human epidermal growth factor receptor 2 antibodies known to mediate critical antigen interactions through CDR H3. Our results show that restricted epitope specificity determined by VH/VL germline segment pairing is a general property of rodent antigen-specific antibodies.
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Affiliation(s)
- Yi-Chun Hsiao
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
| | - Ying-Jiun J Chen
- Department of Molecular Biology, Genentech, South San Francisco, CA, USA
| | - Leonard D Goldstein
- Department of Molecular Biology, Genentech, South San Francisco, CA, USA.,Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA, USA
| | - Jia Wu
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
| | - Zhonghua Lin
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
| | - Kellen Schneider
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
| | - Subhra Chaudhuri
- Department of Molecular Biology, Genentech, South San Francisco, CA, USA
| | - Aju Antony
- Department of Molecular Biology, SciGenom Labs, Cochin, India
| | | | - Zora Modrusan
- Department of Molecular Biology, Genentech, South San Francisco, CA, USA
| | - Dhaya Seshasayee
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
| | | | - Isidro Hötzel
- Department of Antibody Engineering, Genentech, South San Francisco, CA, USA
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8
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Seidah NG, Prat A, Pirillo A, Catapano AL, Norata GD. Novel strategies to target proprotein convertase subtilisin kexin 9: beyond monoclonal antibodies. Cardiovasc Res 2020; 115:510-518. [PMID: 30629143 DOI: 10.1093/cvr/cvz003] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/06/2018] [Accepted: 01/05/2019] [Indexed: 12/15/2022] Open
Abstract
Since the discovery of the role of proprotein convertase subtilisin kexin 9 (PCSK9) in the regulation of low-density lipoprotein cholesterol (LDL-C) in 2003, a paradigm shift in the treatment of hypercholesterolaemia has occurred. The PCSK9 secreted into the circulation is a major downregulator of the low-density lipoprotein receptor (LDLR) protein, as it chaperones it to endosomes/lysosomes for degradation. Humans with loss-of-function of PCSK9 exhibit exceedingly low levels of LDL-C and are protected from atherosclerosis. As a consequence, innovative strategies to modulate the levels of PCSK9 have been developed. Since 2015 inhibitory monoclonal antibodies (evolocumab and alirocumab) are commercially available. When subcutaneously injected every 2-4 weeks, they trigger a ∼60% LDL-C lowering and a 15% reduction in the risk of cardiovascular events. Another promising approach consists of a liver-targetable specific PCSK9 siRNA which results in ∼50-60% LDL-C lowering that lasts up to 6 months (Phases II-III clinical trials). Other strategies under consideration include: (i) antibodies targeting the C-terminal domain of PCSK9, thereby inhibiting the trafficking of PCSK9-LDLR to lysosomes; (ii) small molecules that either prevent PCSK9 binding to the LDLR, its trafficking to lysosomes or its secretion from cells; (iii) complete silencing of PCSK9 by CRISPR-Cas9 strategies; (iv) PCSK9 vaccines that inhibit the activity of circulating PCSK9. Time will tell whether other strategies can be as potent and safe as monoclonal antibodies to lower LDL-C levels.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM; Affiliated to the University of Montreal), Montreal, QC H2W1R7, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute (IRCM; Affiliated to the University of Montreal), Montreal, QC H2W1R7, Canada
| | - Angela Pirillo
- Center for the Study of Atherosclerosis, E. Bassini Hospital, Cinisello Balsamo, Milan, Italy.,IRCCS MultiMedica, Milan, Italy
| | - Alberico Luigi Catapano
- IRCCS MultiMedica, Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Giuseppe Danilo Norata
- Center for the Study of Atherosclerosis, E. Bassini Hospital, Cinisello Balsamo, Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
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9
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Petroglou D, Kanellos I, Savopoulos C, Kaiafa G, Chrysochoou A, Skantzis P, Daios S, Hatzitolios AI, Giannoglou G. The LDL-Receptor and its Molecular Properties: From Theory to Novel Biochemical and Pharmacological Approaches in Reducing LDL-cholesterol. Curr Med Chem 2020; 27:317-333. [PMID: 29865996 DOI: 10.2174/0929867325666180604114819] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 02/25/2018] [Accepted: 05/31/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND The Low-Density Lipoprotein (LDL) Receptor (LDL-R) is a transmembrane protein playing a crucial role in effective lipid homeostasis. Various therapeutic agents have been used in the management of dyslipidemias, however, the outcome of therapeutic target is debated. OBJECTIVE The aim of this review is to summarize and fully understand the current concept regarding LDL-R and its molecular properties, metabolic pathway, factors affecting LDL-R activity and all available pharmacological interventions. Additionally, non-lipid related properties of LDL-R are also referred. METHODS Literature from the PubMed database was extracted to identify papers between 1984 to 2017 regarding LDL-R and therapeutic agents on dyslipidemia management. RESULTS We analyzed basic data regarding agents associated with LDL-R (Sterol Regulating Element-Binding Proteins - SREBPs, Protein ARH, IDOL, Thyroid Hormones, Haematologic Disorders, Protein convertase subtilisin kexintype 9 - PCSK-9, ApoC-III) as well as non-lipid related properties of LDL-R, while all relevant (common and novel) pharmacological interventions (statins, fibrates, cholesterol absorption inhibitors, bile acid sequestrants and PCSK- 9) are also referred. CONCLUSION LDL-R and its molecular properties are involved in lipid homeostasis, so potentially sets the therapeutic goals in cardiovascular patients, which is usually debated. Further research is needed in order to fully understand its properties, as well as to find the potential pharmacological interventions that could be beneficial in cholesterol homeostasis and various morbidities in order to reach the most appropriate therapeutic goal.
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Affiliation(s)
- Dimitrios Petroglou
- 1st Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Ilias Kanellos
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christos Savopoulos
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Georgia Kaiafa
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Anastasios Chrysochoou
- 1st Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Panagiotis Skantzis
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Stylianos Daios
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Apostolos I Hatzitolios
- 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Georgios Giannoglou
- 1st Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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10
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Sarkar SK, Foo ACY, Matyas A, Asikhia I, Kosenko T, Goto NK, Vergara-Jaque A, Lagace TA. A transient amphipathic helix in the prodomain of PCSK9 facilitates binding to low-density lipoprotein particles. J Biol Chem 2020; 295:2285-2298. [PMID: 31949048 PMCID: PMC7039556 DOI: 10.1074/jbc.ra119.010221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 01/13/2020] [Indexed: 01/07/2023] Open
Abstract
Proprotein convertase subtilisin/kexin type-9 (PCSK9) is a ligand of low-density lipoprotein (LDL) receptor (LDLR) that promotes LDLR degradation in late endosomes/lysosomes. In human plasma, 30–40% of PCSK9 is bound to LDL particles; however, the physiological significance of this interaction remains unknown. LDL binding in vitro requires a disordered N-terminal region in PCSK9's prodomain. Here, we report that peptides corresponding to a predicted amphipathic α-helix in the prodomain N terminus adopt helical structure in a membrane-mimetic environment. This effect was greatly enhanced by an R46L substitution representing an atheroprotective PCSK9 loss-of-function mutation. A helix-disrupting proline substitution within the putative α-helical motif in full-length PCSK9 lowered LDL binding affinity >5-fold. Modeling studies suggested that the transient α-helix aligns multiple polar residues to interact with positively charged residues in the C-terminal domain. Gain-of-function PCSK9 mutations associated with familial hypercholesterolemia (FH) and clustered at the predicted interdomain interface (R469W, R496W, and F515L) inhibited LDL binding, which was completely abolished in the case of the R496W variant. These findings shed light on allosteric conformational changes in PCSK9 required for high-affinity binding to LDL particles. Moreover, the initial identification of FH-associated mutations that diminish PCSK9's ability to bind LDL reported here supports the notion that PCSK9-LDL association in the circulation inhibits PCSK9 activity.
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Affiliation(s)
- Samantha K Sarkar
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Alexander C Y Foo
- Department of Chemistry and Biomolecular Sciences, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Angela Matyas
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Ikhuosho Asikhia
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Tanja Kosenko
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada
| | - Natalie K Goto
- Department of Chemistry and Biomolecular Sciences, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Ariela Vergara-Jaque
- Center for Bioinformatics and Molecular Simulation, Universidad de Talca, Talca, Chile; Millennium Nucleus of Ion Channels-associated Diseases (MiNICAD), 3460000 Talca, Chile
| | - Thomas A Lagace
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y 4W7, Canada.
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11
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Lu X. Structure and Function of Proprotein Convertase Subtilisin/kexin Type 9 (PCSK9) in Hyperlipidemia and Atherosclerosis. Curr Drug Targets 2019; 20:1029-1040. [DOI: 10.2174/1389450120666190214141626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 02/01/2023]
Abstract
Background:One of the important factors in Low-Density Lipoprotein (LDL) metabolism is the LDL receptor (LDLR) by its capacity to bind and subsequently clear cholesterol derived from LDL (LDL-C) in the circulation. Proprotein Convertase Subtilisin-like Kexin type 9 (PCSK9) is a newly discovered serine protease that destroys LDLR in the liver and thereby controls the levels of LDL in plasma. Inhibition of PCSK9-mediated degradation of LDLR has, therefore, become a novel target for lipid-lowering therapy.Methods:We review the current understanding of the structure and function of PCSK9 as well as its implications for the treatment of hyperlipidemia and atherosclerosis.Results:New treatments such as monoclonal antibodies against PCSK9 may be useful agents to lower plasma levels of LDL and hence prevent atherosclerosis.Conclusion:PCSK9's mechanism of action is not yet fully clarified. However, treatments that target PCSK9 have shown striking early efficacy and promise to improve the lives of countless patients with hyperlipidemia and atherosclerosis.
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Affiliation(s)
- Xinjie Lu
- The Mary and Garry Weston Molecular Immunology Laboratory, Thrombosis Research Institute, London, SW3 6LR, United Kingdom
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12
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Essalmani R, Weider E, Marcinkiewicz J, Chamberland A, Susan-Resiga D, Roubtsova A, Seidah NG, Prat A. A single domain antibody against the Cys- and His-rich domain of PCSK9 and evolocumab exhibit different inhibition mechanisms in humanized PCSK9 mice. Biol Chem 2019; 399:1363-1374. [PMID: 30044755 DOI: 10.1515/hsz-2018-0194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/09/2018] [Indexed: 11/15/2022]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secreted protein that binds and escorts the low density lipoprotein receptor (LDLR) into the lysosomal degradation pathway. Prescribed monoclonal antibodies (mAbs) against PCSK9 prevent its binding to the LDLR, and result in ~60% lower LDL cholesterol (LDLc) levels. Although efficient, mAbs are expensive. Hence other PCSK9 inhibitors are needed. For screening purpose, we developed C57BL/6J mice expressing the human PCSK9 gene under the control of its own promoter, but lacking endogenous mouse PCSK9. All lines recapitulate the endogenous PCSK9 expression pattern. The Tg2 line that expresses physiological levels of human PCSK9 (hPCSK9) was selected to characterize the inhibitory properties of a previously reported single domain antibody (sdAb), PKF8-mFc, which binds the C-terminal domain of PCSK9. Upon intraveinous injection of 10 mg/kg, PKF8-mFc and the mAb evolocumab neutralized ~50% and 100% of the hPCSK9 impact on total cholesterol (TC) levels, respectively, but PKF8-mFc had a more sustained effect. PKF8-mFc barely affected hPCSK9 levels, whereas evolocumab promoted a 4-fold increase 3 days post-injection, suggesting very different inhibitory mechanisms. The present study also shows that the new transgenic mice are well suited to screen a variety of hPCSK9 inhibitors.
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Affiliation(s)
- Rachid Essalmani
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Elodie Weider
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Jadwiga Marcinkiewicz
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Ann Chamberland
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Delia Susan-Resiga
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Anna Roubtsova
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, Affiliated to the Université de Montréal, 110 Pine Ave. West, Montreal H2W 1R7, QC, Canada
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13
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Marceau West R, Lu W, Rotroff DM, Kuenemann MA, Chang SM, Wu MC, Wagner MJ, Buse JB, Motsinger-Reif AA, Fourches D, Tzeng JY. Identifying individual risk rare variants using protein structure guided local tests (POINT). PLoS Comput Biol 2019; 15:e1006722. [PMID: 30779729 PMCID: PMC6396946 DOI: 10.1371/journal.pcbi.1006722] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 03/01/2019] [Accepted: 12/17/2018] [Indexed: 01/08/2023] Open
Abstract
Rare variants are of increasing interest to genetic association studies because of their etiological contributions to human complex diseases. Due to the rarity of the mutant events, rare variants are routinely analyzed on an aggregate level. While aggregation analyses improve the detection of global-level signal, they are not able to pinpoint causal variants within a variant set. To perform inference on a localized level, additional information, e.g., biological annotation, is often needed to boost the information content of a rare variant. Following the observation that important variants are likely to cluster together on functional domains, we propose a protein structure guided local test (POINT) to provide variant-specific association information using structure-guided aggregation of signal. Constructed under a kernel machine framework, POINT performs local association testing by borrowing information from neighboring variants in the 3-dimensional protein space in a data-adaptive fashion. Besides merely providing a list of promising variants, POINT assigns each variant a p-value to permit variant ranking and prioritization. We assess the selection performance of POINT using simulations and illustrate how it can be used to prioritize individual rare variants in PCSK9, ANGPTL4 and CETP in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) clinical trial data.
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Affiliation(s)
- Rachel Marceau West
- Department of Statistics, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Wenbin Lu
- Department of Statistics, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Daniel M. Rotroff
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Melaine A. Kuenemann
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Sheng-Mao Chang
- Department of Statistics, National Cheng-Kung University, Tainan, Taiwan
| | - Michael C. Wu
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Michael J. Wagner
- Center for Pharmacogenomics and Individualized Therapy, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - John B. Buse
- Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Alison A. Motsinger-Reif
- Department of Statistics, North Carolina State University, Raleigh, North Carolina, United States of America
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Denis Fourches
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, United States of America
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Jung-Ying Tzeng
- Department of Statistics, North Carolina State University, Raleigh, North Carolina, United States of America
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, United States of America
- Department of Statistics, National Cheng-Kung University, Tainan, Taiwan
- Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan
- * E-mail:
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14
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Non-Native Conformational Isomers of the Catalytic Domain of PCSK9 Induce an Immune Response, Reduce Lipids and Increase LDL Receptor Levels. Int J Mol Sci 2018; 19:ijms19020640. [PMID: 29495280 PMCID: PMC5855862 DOI: 10.3390/ijms19020640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 02/16/2018] [Accepted: 02/19/2018] [Indexed: 12/15/2022] Open
Abstract
PCSK9 (Proprotein convertase subtilisin/kexin type 9) increases plasma cholesterol levels by promoting LDL receptor degradation. Current antibody inhibitors block the interaction between PCSK9 and LDL receptors, significantly decrease plasma cholesterol levels, and provide beneficial clinical outcomes. To reduce the action of PCSK9 in plasma, a novel strategy that will produce a panel of non-native, conformationally-altered isomers of PCSK9 (X-PCSK9) to develop active immunotherapy targeting of native PCSK9 and inhibiting/blocking the interaction of PCSK9 with LDL receptor, thus decreasing plasma cholesterol levels is proposed. The authors used the scrambled disulfide bond technique to generate conformationally-altered isomers of the catalytic domain of mouse PCSK9. The focus was on the immune response of four X-isomers and their effects on plasma cholesterol and triglyceride levels in both C57BL/6J and Apoe−/− mice. The authors showed that the four immunogens produced significant immunogenicity against native PCSK9 to day 120 after immunization of C57BL/6J and Apoe−/− mice. This resulted in significantly decreased plasma cholesterol levels in C57BL/6J mice, and to a lesser degree in Apoe−/− mice. The X-PCSK9-B1 treated mice had increased LDL receptor mRNA and protein levels at day 120 after treatment. Thus, this study provides a new, potentially promising approach that uses long-term immunotherapy for a treatment of hypercholesterolemia.
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15
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Physiological and therapeutic regulation of PCSK9 activity in cardiovascular disease. Basic Res Cardiol 2017; 112:32. [PMID: 28439730 PMCID: PMC5403857 DOI: 10.1007/s00395-017-0619-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/07/2017] [Indexed: 12/14/2022]
Abstract
Ischemic heart disease is the main cause of death worldwide and is accelerated by increased levels of low-density lipoprotein cholesterol (LDL-C). Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a potent circulating regulator of LDL-C through its ability to induce degradation of the LDL receptor (LDLR) in the lysosome of hepatocytes. Only in the last few years, a number of breakthroughs in the understanding of PCSK9 biology have been reported illustrating how PCSK9 activity is tightly regulated at several levels by factors influencing its transcription, secretion, or by extracellular inactivation and clearance. Two humanized antibodies directed against the LDLR-binding site in PCSK9 received approval by the European and US authorities and additional PCSK9 directed therapeutics are climbing up the phases of clinical trials. The first outcome data of the PCSK9 inhibitor evolocumab reported a significant reduction in the composite endpoint (cardiovascular death, myocardial infarction, or stroke) and further outcome data are awaited. Meanwhile, it became evident that PCSK9 has (patho)physiological roles in several cardiovascular cells. In this review, we summarize and discuss the recent biological and clinical data on PCSK9, the regulation of PCSK9, its extra-hepatic activities focusing on cardiovascular cells, molecular concepts to target PCSK9, and finally briefly summarize the data of recent clinical studies.
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16
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Abstract
Ischemic heart disease is the main cause of death worldwide and it is accelerated by increased low-density lipoprotein (LDL) cholesterol (LDL-C) and/or lipoprotein (a) (Lp(a)) concentrations. Proprotein convertase subtilisin/kexin type 9 (PCSK9) alters both LDL-C and in part Lp(a) concentrations through its ability to induce degradation of the LDL receptor (LDLR). PCSK9, however, has additional targets which are potentially involved in lipid metabolism regulation such as the very low density lipoprotein receptor (VLDL), CD36 (cluster of differentiation 36) and the epithelial cholesterol transporter (NPC1L1) and it affects expression of apolipoprotein B48. The PCSK9 activity is tightly regulated at several levels by factors influencing its transcription, secretion, or by extracellular inactivation and clearance. Many comorbidities (kidney insufficiency, hypothyreoidism, hyperinsulinemia, inflammation) modify PCSK9 expression and release. Two humanized antibodies directed against extracellular PCSK9 received approval by the European and US authorities and additional PCSK9 directed therapeutics (such as silencing RNA) are already in clinical trials. Their results demonstrate a significant reduction in both LDL-C and Lp(a) concentrations – independent of the concomitant medication – and one of them reduced plaque size in high risk cardiovascular patients; results of two ongoing large clinical endpoints studies are awaited. In this review, we summarize and discuss the recent biological data on PCSK9, the regulation of PCSK9, and finally briefly summarize the data of recent clinical studies in the context of lipid metabolism.
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Affiliation(s)
- Rainer Schulz
- Department of Physiology, Justus-Liebig-Universität, Aulweg 129, 35392, Giessen, Germany.
| | - Klaus-Dieter Schlüter
- Department of Physiology, Justus-Liebig-Universität, Aulweg 129, 35392, Giessen, Germany
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17
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Seidah NG, Abifadel M, Prost S, Boileau C, Prat A. The Proprotein Convertases in Hypercholesterolemia and Cardiovascular Diseases: Emphasis on Proprotein Convertase Subtilisin/Kexin 9. Pharmacol Rev 2016; 69:33-52. [DOI: 10.1124/pr.116.012989] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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18
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Kumano-Kuramochi M, Fujimura T, Komba S, Maeda-Yamamoto M, Machida S. Screening, expression, and characterization of an anti-human oxidized low-density lipoprotein single-chain variable fragment. J Biosci Bioeng 2016; 122:287-93. [DOI: 10.1016/j.jbiosc.2016.02.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/15/2016] [Accepted: 02/29/2016] [Indexed: 12/25/2022]
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19
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Weider E, Susan-Resiga D, Essalmani R, Hamelin J, Asselin MC, Nimesh S, Ashraf Y, Wycoff KL, Zhang J, Prat A, Seidah NG. Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Single Domain Antibodies Are Potent Inhibitors of Low Density Lipoprotein Receptor Degradation. J Biol Chem 2016; 291:16659-71. [PMID: 27284008 DOI: 10.1074/jbc.m116.717736] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Indexed: 01/14/2023] Open
Abstract
Single domain antibodies (sdAbs) correspond to the antigen-binding domains of camelid antibodies. They have the same antigen-binding properties and specificity as monoclonal antibodies (mAbs) but are easier and cheaper to produce. We report here the development of sdAbs targeting human PCSK9 (proprotein convertase subtilisin/kexin type 9) as an alternative to anti-PCSK9 mAbs. After immunizing a llama with human PCSK9, we selected four sdAbs that bind PCSK9 with a high affinity and produced them as fusion proteins with a mouse Fc. All four sdAb-Fcs recognize the C-terminal Cys-His-rich domain of PCSK9. We performed multiple cellular assays and demonstrated that the selected sdAbs efficiently blocked PCSK9-mediated low density lipoprotein receptor (LDLR) degradation in cell lines, in human hepatocytes, and in mouse primary hepatocytes. We further showed that the sdAb-Fcs do not affect binding of PCSK9 to the LDLR but rather block its induced cellular LDLR degradation. Pcsk9 knock-out mice expressing a human bacterial artificial chromosome (BAC) transgene were generated, resulting in plasma levels of ∼300 ng/ml human PCSK9. Mice were singly or doubly injected with the best sdAb-Fc and analyzed at day 4 or 11, respectively. After 4 days, mice exhibited a 32 and 44% decrease in the levels of total cholesterol and apolipoprotein B and ∼1.8-fold higher liver LDLR protein levels. At 11 days, the equivalent values were 24 and 46% and ∼2.3-fold higher LDLR proteins. These data constitute a proof-of-principle for the future usage of sdAbs as PCSK9-targeting drugs that can efficiently reduce LDL-cholesterol, and as tools to study the Cys-His-rich domain-dependent sorting the PCSK9-LDLR complex to lysosomes.
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Affiliation(s)
- Elodie Weider
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Delia Susan-Resiga
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Rachid Essalmani
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Josée Hamelin
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Marie-Claude Asselin
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Surendra Nimesh
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Yahya Ashraf
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Keith L Wycoff
- Planet Biotechnology Inc., Hayward, California 94545-2740, and
| | - Jianbing Zhang
- the Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Annik Prat
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Nabil G Seidah
- From the Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada,
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Misasi J, Gilman MSA, Kanekiyo M, Gui M, Cagigi A, Mulangu S, Corti D, Ledgerwood JE, Lanzavecchia A, Cunningham J, Muyembe-Tamfun JJ, Baxa U, Graham BS, Xiang Y, Sullivan NJ, McLellan JS. Structural and molecular basis for Ebola virus neutralization by protective human antibodies. Science 2016; 351:1343-6. [PMID: 26917592 PMCID: PMC5241105 DOI: 10.1126/science.aad6117] [Citation(s) in RCA: 156] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 02/17/2016] [Indexed: 12/18/2022]
Abstract
Ebola virus causes hemorrhagic fever with a high case fatality rate for which there is no approved therapy. Two human monoclonal antibodies, mAb100 and mAb114, in combination, protect nonhuman primates against all signs of Ebola virus disease, including viremia. Here, we demonstrate that mAb100 recognizes the base of the Ebola virus glycoprotein (GP) trimer, occludes access to the cathepsin-cleavage loop, and prevents the proteolytic cleavage of GP that is required for virus entry. We show that mAb114 interacts with the glycan cap and inner chalice of GP, remains associated after proteolytic removal of the glycan cap, and inhibits binding of cleaved GP to its receptor. These results define the basis of neutralization for two protective antibodies and may facilitate development of therapies and vaccines.
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Affiliation(s)
- John Misasi
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA. Division of Infectious Diseases, Boston Children's Hospital, Boston, MA 02215, USA
| | - Morgan S A Gilman
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Masaru Kanekiyo
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Miao Gui
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084 China
| | - Alberto Cagigi
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sabue Mulangu
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Davide Corti
- Institute for Research in Biomedicine, Università della Svizzera Italiana, CH-6500 Bellinzona, Switzerland
| | - Julie E Ledgerwood
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Antonio Lanzavecchia
- Institute for Research in Biomedicine, Università della Svizzera Italiana, CH-6500 Bellinzona, Switzerland. Institute of Microbiology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - James Cunningham
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jean Jacques Muyembe-Tamfun
- National Institute for Biomedical Research, National Laboratory of Public Health, Kinshasa B.P. 1197, Democratic Republic of the Congo
| | - Ulrich Baxa
- Electron Microscopy Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ye Xiang
- Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084 China.
| | - Nancy J Sullivan
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jason S McLellan
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
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21
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Wang Y, Ye J, Li J, Chen C, Huang J, Liu P, Huang H. Polydatin ameliorates lipid and glucose metabolism in type 2 diabetes mellitus by downregulating proprotein convertase subtilisin/kexin type 9 (PCSK9). Cardiovasc Diabetol 2016; 15:19. [PMID: 26833058 PMCID: PMC4736185 DOI: 10.1186/s12933-015-0325-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 12/28/2015] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Abnormalities in lipid and glucose metabolism are constantly observed in type 2 diabetes. However, these abnormalities can be ameliorated by polydatin. Considering the important role of proprotein convertase subtilisin/kexin type 9 (PCSK9) in metabolic diseases, we explore the possible mechanism of polydatin on lipid and glucose metabolism through its effects on PCSK9. METHODS An insulin-resistant HepG2 cell model induced by palmitic acid (PA) and a db/db mice model were used to clarify the role of polydatin on lipid and glucose metabolism. RESULTS In insulin-resistant HepG2 cells, polydatin upregulated the protein levels of LDLR and GCK but repressed PCSK9 protein expression, besides, polydatin also inhibited the combination between PCSK9 and LDLR. Knockdown and overexpression experiments indicated that polydatin regulated LDLR and GCK expressions through PCSK9. In the db/db mice model, we found that polydatin markedly enhanced GCK and LDLR protein levels, and inhibited PCSK9 expression in the liver. Molecular docking assay was further performed to analyze the possible binding mode between polydatin and the PCSK9 crystal structure (PDB code: 2p4e), which indicated that steady hydrogen bonds formed between polydatin and PCSK9. CONCLUSIONS Our study indicates that polydatin ameliorates lipid and glucose metabolism in type 2 diabetes mellitus by downregulating PCSK9.
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Affiliation(s)
- Yu Wang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China.
| | - Jiantao Ye
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China. .,National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangzhou, 510006, China.
| | - Jie Li
- Laboratory Animal Center, Sun Yat-sen University, Guangzhou, 510080, China.
| | - Cheng Chen
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China.
| | - Junying Huang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China.
| | - Peiqing Liu
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China. .,National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangzhou, 510006, China.
| | - Heqing Huang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-sen University, 132 WaiHuan East Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China. .,Laboratory Animal Center, Sun Yat-sen University, Guangzhou, 510080, China. .,National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangzhou, 510006, China.
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22
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Crossey E, Amar MJA, Sampson M, Peabody J, Schiller JT, Chackerian B, Remaley AT. A cholesterol-lowering VLP vaccine that targets PCSK9. Vaccine 2015; 33:5747-5755. [PMID: 26413878 DOI: 10.1016/j.vaccine.2015.09.044] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/15/2015] [Accepted: 09/17/2015] [Indexed: 01/01/2023]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secretory protein that controls cholesterol homeostasis by enhancing endosomal and lysosomal degradation of the low-density lipoprotein receptor (LDL-R). Mutations that cause increased activity of PCSK9 are associated with hypercholesterolemia, atherosclerosis and early cardiovascular disease (CVD), whereas individuals with loss-of-function mutations in PCSK9 are apparently healthy but are hypocholesterolemic and have a dramatically decreased risk of CVD. In this study, we generated virus-like particle (VLP)-based vaccines targeting PCSK9. Mice and macaques vaccinated with bacteriophage VLPs displaying PCSK9-derived peptides developed high titer IgG antibodies that bound to circulating PCSK9. Vaccination was associated with significant reductions in total cholesterol, free cholesterol, phospholipids, and triglycerides. A vaccine targeting PCSK9 may, therefore, be an attractive alternative to monoclonal antibody-based therapies.
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Affiliation(s)
- Erin Crossey
- Department of Molecular Genetics and Microbiology, University of New Mexico, MSC08-4660, Albuquerque, NM 87131, USA
| | - Marcelo J A Amar
- Lipoprotein Metabolism Section, Cardio-Pulmonary Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Building 10 - 2C433, 10 Center Drive, MSC 1666, Bethesda, MD 20892, USA
| | - Maureen Sampson
- Lipoprotein Metabolism Section, Cardio-Pulmonary Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Building 10 - 2C433, 10 Center Drive, MSC 1666, Bethesda, MD 20892, USA
| | - Julianne Peabody
- Department of Molecular Genetics and Microbiology, University of New Mexico, MSC08-4660, Albuquerque, NM 87131, USA
| | - John T Schiller
- Laboratory of Cellular Oncology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bryce Chackerian
- Department of Molecular Genetics and Microbiology, University of New Mexico, MSC08-4660, Albuquerque, NM 87131, USA.
| | - Alan T Remaley
- Lipoprotein Metabolism Section, Cardio-Pulmonary Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Building 10 - 2C433, 10 Center Drive, MSC 1666, Bethesda, MD 20892, USA.
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23
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Schroeder KM, Beyer TP, Hansen RJ, Han B, Pickard RT, Wroblewski VJ, Kowala MC, Eacho PI. Proteolytic cleavage of antigen extends the durability of an anti-PCSK9 monoclonal antibody. J Lipid Res 2015; 56:2124-32. [PMID: 26392590 DOI: 10.1194/jlr.m061903] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Indexed: 11/20/2022] Open
Abstract
Lilly PCSK9 antibody LY3015014 (LY) is a monoclonal antibody (mAb) that neutralizes proprotein convertase subtilisin-kexin type 9 (PCSK9). LY decreases LDL cholesterol in monkeys and, unlike other PCSK9 mAbs, does not cause an accumulation of intact PCSK9 in serum. Comparing the epitope of LY with other clinically tested PCSK9 mAbs, it was noted that the LY epitope excludes the furin cleavage site in PCSK9, whereas other mAbs span this site. In vitro exposure of PCSK9 to furin resulted in degradation of PCSK9 bound to LY, whereas cleavage was blocked by other mAbs. These other mAbs caused a significant accumulation of serum PCSK9 and displayed a shorter duration of LDL-cholesterol lowering than LY when administered to mice expressing the WT human PCSK9. In mice expressing a noncleavable variant of human PCSK9, LY behaved like a cleavage-blocking mAb, in that it caused significant PCSK9 accumulation, its duration of LDL lowering was reduced, and its clearance (CL) from serum was accelerated. Thus, LY neutralizes PCSK9 and allows its proteolytic degradation to proceed, which limits PCSK9 accumulation, reduces the CL rate of LY, and extends its duration of action. PCSK9 mAbs with this property are likely to achieve longer durability and require lower doses than mAbs that cause antigen to accumulate.
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Affiliation(s)
- Krista M Schroeder
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | - Thomas P Beyer
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | - Ryan J Hansen
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | - Bomie Han
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | - Richard T Pickard
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | | | - Mark C Kowala
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
| | - Patrick I Eacho
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285
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Geschwindner S, Andersson GMK, Beisel HG, Breuer S, Hallberg C, Kihlberg BM, Lindqvist AM, O'Mahony G, Plowright AT, Raubacher F, Knecht W. Characterisation of de novo mutations in the C-terminal domain of proprotein convertase subtilisin/kexin type 9. Protein Eng Des Sel 2015; 28:117-25. [PMID: 25744035 DOI: 10.1093/protein/gzv008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 02/02/2015] [Indexed: 11/14/2022] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the degradation of the hepatic low-density lipoprotein receptor (LDL-R) and is therefore a prominent therapeutic target for reducing LDL-cholesterol. The C-terminal domain of PCSK9 is unlikely to be involved in a direct extracellular interaction with the LDL-R. We probed the importance of the C-terminus for the degradation of the LDL-R by designing seven de novo mutants of PCSK9 that fill potential druggable cavities. The mutants were tested for their ability to diminish LDL uptake in human HepG2 cells and for affinity towards a calcium independent mutant of the EGF(A) domain of the human LDL-R. The later was done by a newly developed surface plasmon resonance-based assay format. We identified three mutant proteins (G517R, V610R and V644R) with decreased ability to block LDL uptake into HepG2 cells. These mutations define areas outside the direct interaction area between PCSK9 and the LDL-R that could be targeted to inhibit the PCSK9 triggered degradation of the LDL-R. We also describe the mechanistic rationalisation of the affinity changes seen with the natural occurring human D374Y (gain of function) mutation causing severe hypercholesterolaemia. The action of this mutant is due to a significantly decreased dissociation rate constant, whereas the mutation does not affect the association rate constant.
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Affiliation(s)
| | | | - Hans-Georg Beisel
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | - Sebastian Breuer
- Discovery Sciences, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | - Carina Hallberg
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | | | | | - Gavin O'Mahony
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | - Alleyn T Plowright
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | - Florian Raubacher
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden
| | - Wolfgang Knecht
- CVMD Innovative Medicines, AstraZeneca R&D Mölndal, 431 83 Mölndal, Sweden Present address: Department of Biology, Molecular Cell Biology & Lund Protein Production Platform, Lund University, 22362 Lund, Sweden
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25
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Schulz R, Schlüter KD, Laufs U. Molecular and cellular function of the proprotein convertase subtilisin/kexin type 9 (PCSK9). Basic Res Cardiol 2015; 110:4. [PMID: 25600226 PMCID: PMC4298671 DOI: 10.1007/s00395-015-0463-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 01/04/2015] [Accepted: 01/07/2015] [Indexed: 12/16/2022]
Abstract
The proprotein convertase subtilisin/kexin type 9 (PCSK9) has emerged as a promising treatment target to lower serum cholesterol, a major risk factor of cardiovascular diseases. Gain-of-function mutations of PCSK9 are associated with hypercholesterolemia and increased risk of cardiovascular events. Conversely, loss-of-function mutations cause low-plasma LDL-C levels and a reduction of cardiovascular risk without known unwanted effects on individual health. Experimental studies have revealed that PCSK9 reduces the hepatic uptake of LDL-C by increasing the endosomal and lysosomal degradation of LDL receptors (LDLR). A number of clinical studies have demonstrated that inhibition of PCSK9 alone and in addition to statins potently reduces serum LDL-C concentrations. This review summarizes the current data on the regulation of PCSK9, its molecular function in lipid homeostasis and the emerging evidence on the extra-hepatic effects of PCSK9.
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Affiliation(s)
- Rainer Schulz
- Physiologisches Institut, Justus-Liebig Universität Giessen, Aulweg 129, 35392, Giessen, Germany,
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26
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Sorting an LDL receptor with bound PCSK9 to intracellular degradation. Atherosclerosis 2014; 237:76-81. [PMID: 25222343 DOI: 10.1016/j.atherosclerosis.2014.08.038] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 07/28/2014] [Accepted: 08/19/2014] [Indexed: 11/21/2022]
Abstract
OBJECTIVE This article reviews the mechanism by which the low density lipoprotein receptor (LDLR) that has bound proprotein convertase subtilisin/kexin type 9 (PCSK9), is rerouted to intracellular degradation instead of being recycled. METHODS A search of relevant published literature has been conducted. RESULTS PCSK9 binds to the LDLR at the cell surface. It is the catalytic domain of PCSK9 that binds to the epidermal growth factor repeat A of the LDLR. The LDLR:PCSK9 complex is internalized through clathrin-mediated endocytosis. Due to an additional electrostatic interaction at acidic pH between the C-terminal domain of PCSK9 and the ligand-binding domain of the LDLR, PCSK9 remains bound to the LDLR in the sorting endosome. As a consequence, the LDLR fails to adopt a closed conformation and is degraded instead of being recycled. The mechanism for the failure of the LDLR to recycle appears to involve ectodomain cleavage of the extended LDLR by a cysteine cathepsin in the sorting endosome. The cleaved LDLR ectodomain will be confined to the vesicular part of the sorting endosome for degradation in the endosomal/lysosomal tract. CONCLUSION Ectodomain cleavage of an LDLR with bound PCSK9 in the sorting endosome disrupts the normal recycling of the LDLR.
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27
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Dragan S, Serban MC, Banach M. Proprotein convertase subtilisin/kexin 9 inhibitors: an emerging lipid-lowering therapy? J Cardiovasc Pharmacol Ther 2014; 20:157-68. [PMID: 24938457 DOI: 10.1177/1074248414539562] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Proprotein convertase subtilisin/kexin 9 (PCSK9) is part of the proteinase K subfamily of subtilases and plays a key role in lipid metabolism. It increases degradation of the low-density lipoprotein receptor (LDL-R), modulates cholesterol metabolism and transport, and contributes to the production of apolipoprotein B (apoB) in intestinal cells. Exogenous PCSK9 modifies the activity of 3-hydroxy-3-methylglutaryl-coenzyme A reductase and acyl coenzyme A:cholesterol acyltransferase and enhances secretion of chylomicrons by modulating production of lipids and apoB-48. Statins increase PCSK9 messenger RNA expression and attenuate the capacity to increase LDL-R levels. Therefore, the inhibition of PCSK9 in combination with statins provides a promising approach for lowering low-density lipoprotein cholesterol (LDL-C) concentrations. This review will address new therapeutic strategies targeting PCSK9, including monoclonal antibodies, antisense oligonucleotides, small interfering RNAs, and other small molecule inhibitors. Further studies are still needed to determine the efficacy and safety of the PCSK9 inhibitors not only to decrease LDL-C but also to investigate the potential underlying mechanisms involved and to test whether these compounds actually reduce cardiovascular end points and mortality.
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Affiliation(s)
- Simona Dragan
- Department of Cardiology, University of Medicine and Pharmacy "Victor Babes" Timisoara, Timisoara, Romania Center for Interdisciplinary Research, University of Medicine and Pharmacy "Victor Babes" Timisoara, Timisoara, Romania
| | - Maria-Corina Serban
- Center for Interdisciplinary Research, University of Medicine and Pharmacy "Victor Babes" Timisoara, Timisoara, Romania Department of Functional Sciences, Chair of Pathophysiology, University of Medicine and Pharmacy "Victor Babes" Timisoara, Timisoara, Romania
| | - Maciej Banach
- Department of Hypertension, Chair of Nephrology and Hypertension, Medical University of Lodz, Poland
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28
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Ly K, Saavedra YGL, Canuel M, Routhier S, Desjardins R, Hamelin J, Mayne J, Lazure C, Seidah NG, Day R. Annexin A2 reduces PCSK9 protein levels via a translational mechanism and interacts with the M1 and M2 domains of PCSK9. J Biol Chem 2014; 289:17732-46. [PMID: 24808179 DOI: 10.1074/jbc.m113.541094] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Annexin A2 (AnxA2) was reported to be an extracellular endogenous inhibitor of proprotein convertase subtilisin kexin type 9 (PCSK9) activity on cell-surface LDL receptor degradation. In this study, we investigated the effect of silencing the expression of AnxA2 and PCSK9 in HepG2 and Huh7 cells to better define the role of AnxA2 in PCSK9 regulation. AnxA2 knockdown in Huh7 cells significantly increased PCSK9 protein levels as opposed to AnxA2 knockdown in HepG2 cells. However, HepG2 cells overexpressing AnxA2 had lower levels of PCSK9 protein. Overall, our data revealed a plausible new role of AnxA2 in the reduction of PCSK9 protein levels via a translational mechanism. Moreover, the C-terminal Cys/His-rich domain of PCSK9 is crucial in the regulation of PCSK9 activity, and we demonstrated by far-Western blot assay that the M1 and M2 domains are necessary for the specific interaction of PCSK9's C-terminal Cys/His-rich domain and AnxA2. Finally, we produced and purified recombinant PCSK9 from humans and mice, which was characterized and used to perform 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate LDL cell-based assays on the stable knockdown HepG2 and Huh7 cells. We also demonstrated for the first time the equipotency of human and mouse PCSK9 R218S on human cells.
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Affiliation(s)
- Kévin Ly
- From the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4
| | | | | | - Sophie Routhier
- From the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4
| | - Roxane Desjardins
- From the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4
| | - Josée Hamelin
- the Laboratories of Biochemical Neuroendocrinology and
| | - Janice Mayne
- the Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H8M5, Canada
| | - Claude Lazure
- Neuropeptides Structure and Metabolism, Institut de Recherches Cliniques de Montréal, Université de Montréal, Montreal H2W1R7, Quebec, and
| | | | - Robert Day
- From the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H5N4,
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