{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,25]],"date-time":"2026-04-25T00:35:11Z","timestamp":1777077311828,"version":"3.51.4"},"reference-count":43,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,11,3]],"date-time":"2020-11-03T00:00:00Z","timestamp":1604361600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001322","name":"South African Medical Research Council","doi-asserted-by":"publisher","award":["A0X331"],"award-info":[{"award-number":["A0X331"]}],"id":[{"id":"10.13039\/501100001322","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004191","name":"Novo Nordisk","doi-asserted-by":"publisher","award":["NNF10CC1016517"],"award-info":[{"award-number":["NNF10CC1016517"]}],"id":[{"id":"10.13039\/501100004191","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Progressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular issues, and the manifestations may include thrombotic complications. These thrombotic pathologies may be both extrapulmonary and intrapulmonary and may be central to respiratory failure. Previously, we reported the presence of amyloid microclots in the circulation of patients with coronavirus disease 2019 (COVID-19). Here, we investigate the presence of related circulating biomarkers, including C-reactive protein (CRP), serum ferritin, and P-selectin. These biomarkers are well-known to interact with, and cause pathology to, platelets and erythrocytes. We also study the structure of platelets and erythrocytes using fluorescence microscopy (using the markers PAC-1 and CD62PE) and scanning electron microscopy. Thromboelastography and viscometry were also used to study coagulation parameters and plasma viscosity. We conclude that structural pathologies found in platelets and erythrocytes, together with spontaneously formed amyloid microclots, may be central to vascular changes observed during COVID-19 progression, including thrombotic microangiopathy, diffuse intravascular coagulation, and large-vessel thrombosis, as well as ground-glass opacities in the lungs. Consequently, this clinical snapshot of COVID-19 strongly suggests that it is also a true vascular disease and considering it as such should form an essential part of a clinical treatment regime.<\/jats:p>","DOI":"10.3390\/ijms21218234","type":"journal-article","created":{"date-parts":[[2020,11,3]],"date-time":"2020-11-03T09:09:32Z","timestamp":1604394572000},"page":"8234","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":79,"title":["Erythrocyte, Platelet, Serum Ferritin, and P-Selectin Pathophysiology Implicated in Severe Hypercoagulation and Vascular Complications in COVID-19"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3067-8184","authenticated-orcid":false,"given":"Chantelle","family":"Venter","sequence":"first","affiliation":[{"name":"Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3849-6905","authenticated-orcid":false,"given":"Johannes Andries","family":"Bezuidenhout","sequence":"additional","affiliation":[{"name":"Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gert Jacobus","family":"Laubscher","sequence":"additional","affiliation":[{"name":"Suite 104, 1 Elsie du Toit Street, Mediclinic Stellenbosch, Stellenbosch 7600, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Petrus Johannes","family":"Lourens","sequence":"additional","affiliation":[{"name":"Suite 104, 1 Elsie du Toit Street, Mediclinic Stellenbosch, Stellenbosch 7600, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Janami","family":"Steenkamp","sequence":"additional","affiliation":[{"name":"PathCare Laboratories, PathCare Business Centre, PathCare Park, Neels Bothma Street, N1 City 7460, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5838-7963","authenticated-orcid":false,"given":"Douglas B.","family":"Kell","sequence":"additional","affiliation":[{"name":"Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa"},{"name":"Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Crown St, Liverpool L69 7ZB, UK"},{"name":"The Novo Nordisk Foundation Centre for Biosustainability, Building 220, Kemitorvet, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9108-2384","authenticated-orcid":false,"given":"Etheresia","family":"Pretorius","sequence":"additional","affiliation":[{"name":"Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1038\/d41586-020-01403-8","article-title":"Coronavirus blood-clot mystery intensifies","volume":"581","author":"Willyard","year":"2020","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1039","DOI":"10.1126\/science.368.6495.1039","article-title":"Blood vessel injury may spur disease\u2019s fatal second phase","volume":"368","author":"Matacic","year":"2020","journal-title":"Science"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e630","DOI":"10.1016\/S2352-3026(20)30218-0","article-title":"Coagulation disorder in COVID-19","volume":"7","author":"Kander","year":"2020","journal-title":"Lancet Haematol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e671","DOI":"10.1016\/S2352-3026(20)30217-9","article-title":"Haematological characteristics and risk factors in the classification and prognosis evaluation of COVID-19: A retrospective cohort study","volume":"7","author":"Liao","year":"2020","journal-title":"Lancet Haematol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1038\/s41577-020-0343-0","article-title":"COVID-19: The vasculature unleashed","volume":"20","author":"Teuwen","year":"2020","journal-title":"Nat. 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