{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T16:10:10Z","timestamp":1790784610426,"version":"4.1.0"},"reference-count":27,"publisher":"SAGE Publications","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Viral Immunology"],"abstract":"<jats:sec>\n                    <jats:title>\n                      <jats:italic toggle=\"yes\">Introduction:<\/jats:italic>\n                    <\/jats:title>\n                    <jats:p>COVID-19 presents with various symptoms, including fever, dyspnea, and respiratory failure. Understanding its pathogenesis is crucial, particularly the role of early immune responders such as neutrophils.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>\n                      <jats:italic toggle=\"yes\">Objectives:<\/jats:italic>\n                    <\/jats:title>\n                    <jats:p>The study aimed to investigate neutrophil phenotypes and activation in patients with severe COVID-19, focusing on the expression of key activation markers and their potential role in disease severity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>\n                      <jats:italic toggle=\"yes\">Methods:<\/jats:italic>\n                    <\/jats:title>\n                    <jats:p>A case-control study was conducted in Makkah City involving 88 participants. The study group consisted of 48 PCR-confirmed severe COVID-19 patients with elevated C-reactive protein (CRP) levels and proinflammatory cytokine levels, and the control group included 40 healthy individuals. EDTA-anticoagulated whole blood samples were collected from all participants. Neutrophil counts were obtained, and flow cytometry was performed to assess the expression of activation markers CD64 and HLA-DR on neutrophils.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>\n                      <jats:italic toggle=\"yes\">Results:<\/jats:italic>\n                    <\/jats:title>\n                    <jats:p>Severe COVID-19 patients exhibited significantly elevated neutrophil counts compared to healthy controls. Flow cytometric analysis revealed significantly increased CD64 and HLA-DR mean fluorescence intensity on neutrophils from patients with severe COVID-19 compared with healthy controls, indicating a heightened state of neutrophil activation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>\n                      <jats:italic toggle=\"yes\">Conclusion:<\/jats:italic>\n                    <\/jats:title>\n                    <jats:p>Severe COVID-19 was associated with increased neutrophil activation, reflected by elevated CD64 and HLA-DR expression. These findings support the potential value of neutrophil immunophenotyping in characterizing innate immune dysregulation during severe COVID-19.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/08828245261493338","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T04:46:42Z","timestamp":1790657202000},"update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Increased Neutrophil CD64 and HLA-DR Expression in Severe COVID-19: A Case-Control Flow Cytometry Study"],"prefix":"10.1177","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7654-9759","authenticated-orcid":false,"given":"Abdulelah","family":"Aljuaid","sequence":"first","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mamdouh","family":"Allahyani","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Izmirly","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia."},{"name":"Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad M.","family":"Alharbi","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Khalid","family":"Jambi","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mazen","family":"Almehmadi","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2026,9,28]]},"reference":[{"key":"e_1_3_3_2_1","doi-asserted-by":"publisher","DOI":"10.3390\/jcm13195664"},{"key":"e_1_3_3_3_1","doi-asserted-by":"publisher","DOI":"10.1007\/s12291-022-01087-z"},{"key":"e_1_3_3_4_1","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2022.820058"},{"key":"e_1_3_3_5_1","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCULATIONAHA.120.050656"},{"key":"e_1_3_3_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cytogfr.2020.06.001"},{"issue":"1","key":"e_1_3_3_7_1","first-page":"157","article-title":"WHO declares COVID-19 a pandemic","volume":"91","author":"Cucinotta D","year":"2020","unstructured":"Cucinotta D, , Vanelli M. WHO declares COVID-19 a pandemic. Acta Biomed 2020;91(1):157\u2013160.","journal-title":"Acta Biomed"},{"key":"e_1_3_3_8_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41591-020-1051-9"},{"key":"e_1_3_3_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jim.2014.07.011"},{"key":"e_1_3_3_10_1","doi-asserted-by":"publisher","DOI":"10.1080\/00365540500348929"},{"key":"e_1_3_3_11_1","doi-asserted-by":"publisher","DOI":"10.1186\/s44158-023-00090-x"},{"key":"e_1_3_3_12_1","doi-asserted-by":"publisher","DOI":"10.5694\/mja2.50674"},{"key":"e_1_3_3_13_1","doi-asserted-by":"publisher","DOI":"10.4049\/jimmunol.151.3.1482"},{"key":"e_1_3_3_14_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1523-1755.1999.00446.x"},{"key":"e_1_3_3_15_1","doi-asserted-by":"publisher","DOI":"10.1515\/CCLM.2009.224"},{"key":"e_1_3_3_16_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1523-1755.2001.00068.x"},{"key":"e_1_3_3_17_1","doi-asserted-by":"publisher","DOI":"10.1177\/20499361211034065"},{"key":"e_1_3_3_18_1","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2017.01781"},{"key":"e_1_3_3_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(03)13413-7"},{"key":"e_1_3_3_20_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2249.2001.01596.x"},{"key":"e_1_3_3_21_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2249.2003.02245.x"},{"key":"e_1_3_3_22_1","doi-asserted-by":"publisher","DOI":"10.1182\/blood.V87.7.3068.bloodjournal8773068"},{"key":"e_1_3_3_23_1","doi-asserted-by":"publisher","DOI":"10.1002\/cyto.b.21216"},{"key":"e_1_3_3_24_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ebiom.2021.103357"},{"key":"e_1_3_3_25_1","doi-asserted-by":"publisher","DOI":"10.1093\/rb\/rbw041"},{"key":"e_1_3_3_26_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.it.2019.04.012"},{"key":"e_1_3_3_27_1","doi-asserted-by":"publisher","DOI":"10.1084\/jem.20201129"},{"key":"e_1_3_3_28_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41392-024-02049-y"}],"container-title":["Viral Immunology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/08828245261493338","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/08828245261493338","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/08828245261493338","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T15:46:19Z","timestamp":1790783179000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/08828245261493338"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,28]]},"references-count":27,"alternative-id":["10.1177\/08828245261493338"],"URL":"https:\/\/doi.org\/10.1177\/08828245261493338","relation":{},"ISSN":["0882-8245","1557-8976"],"issn-type":[{"value":"0882-8245","type":"print"},{"value":"1557-8976","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,28]]},"article-number":"08828245261493338"}}