1
|
Martos L, Ramón LA, Oto J, Fernández-Pardo Á, Bonanad S, Cid AR, Gruber A, Griffin JH, España F, Navarro S, Medina P. α2-Macroglobulin Is a Significant In Vivo Inhibitor of Activated Protein C and Low APC:α2M Levels Are Associated with Venous Thromboembolism. Thromb Haemost 2018; 118:630-638. [PMID: 29448296 PMCID: PMC6002867 DOI: 10.1055/s-0038-1629902] [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: 10/18/2022]
Abstract
BACKGROUND Activated protein C (APC) is a major regulator of thrombin formation. Two major plasma inhibitors form complexes with APC, protein C inhibitor (PCI) and α1-antitrypsin (α1AT), and these complexes have been quantified by specific enzyme-linked immunosorbent assays (ELISAs). Also, complexes of APC with α2-macroglobulin (α2M) have been observed by immunoblotting. Here, we report an ELISA for APC:α2M complexes in plasma. METHODS Plasma samples were pre-treated with dithiothreitol and then with iodoacetamide. The detection range of the newly developed APC:α2M assay was 0.031 to 8.0 ng/mL of complexed APC. Following infusions of APC in humans and baboons, complexes of APC with α2M, PCI and α1AT were quantified. These complexes as well as circulating APC were also measured in 121 patients with a history of venous thromboembolism (VTE) and 119 matched controls. RESULTS In all the in vivo experiments, α2M was a significant APC inhibitor. The VTE case-control study showed that VTE patients had significantly lower APC:α2M and APC levels than the controls (p < 0.001). Individuals in the lowest quartile of APC:α2M or the lowest quartile of APC had approximately four times more VTE risk than those in the highest quartile of APC:α2M or of APC. The risk increased for individuals with low levels of both parameters. CONCLUSION The APC:α2M assay reported here may be useful to help monitor the in vivo fate of APC in plasma. In addition, our results show that a low APC:α2M level is associated with increased VTE risk.
Collapse
Affiliation(s)
- Laura Martos
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Luis Andrés Ramón
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Julia Oto
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Álvaro Fernández-Pardo
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Santiago Bonanad
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain,Unidad de Trombosis y Hemostasia, Servicio de Hematología, Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Ana Rosa Cid
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain,Unidad de Trombosis y Hemostasia, Servicio de Hematología, Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Andras Gruber
- Department of Biomedical Engineering, Oregon Health and Science University, Portland, Oregon, United States
| | - John H. Griffin
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Francisco España
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Silvia Navarro
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - Pilar Medina
- Grupo de Investigación en Hemostasia, Trombosis, Arteriosclerosis y Biología Vascular, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Hospital Universitario y Politécnico La Fe, Valencia, Spain
| |
Collapse
|
2
|
Martos L, Bonanad S, Ramón LA, Cid AR, Bonet E, Corral J, Miralles M, España F, Navarro S, Medina P. A simplified assay for the quantification of circulating activated protein C. Clin Chim Acta 2016; 459:101-104. [DOI: 10.1016/j.cca.2016.05.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 05/26/2016] [Accepted: 05/27/2016] [Indexed: 10/21/2022]
|
3
|
Anastasiou G, Politou M, Rallidis L, Grouzi E, Karakitsos P, Merkouri E, Travlou A, Gialeraki A. Endothelial Protein C Receptor Gene Variants and Risk of Thrombosis. Clin Appl Thromb Hemost 2014; 22:199-204. [DOI: 10.1177/1076029614547261] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Endothelial protein C receptor (EPCR) is a candidate mediator in the pathogenesis of thrombosis, as several data in the literature indicate that polymorphisms such as EPCR 4678G/C and 4600A/G are associated with either protective effect or increased risk of thrombosis, respectively. We investigated the prevalence of these polymorphisms in patients with thrombotic disorders as well as their impact on the risk of thrombosis, the age of first thrombotic episode, and recurrence. The prevalence of the rare EPCR alleles 4600G and 4678C was comparable in patients and controls. However, in a subset analysis, we observed that 4600G allele was more prevalent among patients who developed thrombosis at younger age (<35 years). Moreover, the prevalence of 4678C allele was significantly lower in younger patients compared to older patients. Neither polymorphism seemed to have an impact on recurrence regardless of age. Soluble EPCR levels were elevated in 4600AG patients compared to controls while 4678CC patients presented with lower levels of soluble form of EPCR compared to carriers of at least 1 4678G allele. Our data suggest that either the lack of the protective EPCR 4678C allele or the presence of EPCR 4600G allele may be associated with earlier development of thrombosis.
Collapse
Affiliation(s)
- Georgia Anastasiou
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Marianna Politou
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Loukianos Rallidis
- Second Department of Cardiology, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Elisavet Grouzi
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Petros Karakitsos
- Department of Cytology, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Efrosini Merkouri
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Anthi Travlou
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Argyri Gialeraki
- Laboratory of Haematology and Blood Transfusion Unit, Attikon Hospital, School of Medicine, University of Athens, Athens, Greece
| |
Collapse
|