{"id":33313,"date":"2025-05-23T12:51:40","date_gmt":"2025-05-23T10:51:40","guid":{"rendered":"https:\/\/inmuno.es\/index.php\/2025\/05\/23\/specific-thresholds-of-circulating-antibody-titers-predict-against-infection-and-reduced-disease-severity-in-sars-cov-2-close-contacts\/"},"modified":"2025-05-23T12:51:40","modified_gmt":"2025-05-23T10:51:40","slug":"specific-thresholds-of-circulating-antibody-titers-predict-against-infection-and-reduced-disease-severity-in-sars-cov-2-close-contacts","status":"publish","type":"post","link":"https:\/\/inmuno.es\/index.php\/2025\/05\/23\/specific-thresholds-of-circulating-antibody-titers-predict-against-infection-and-reduced-disease-severity-in-sars-cov-2-close-contacts\/","title":{"rendered":"Specific thresholds of circulating antibody titers predict against infection and reduced disease severity in SARS-CoV-2 close contacts"},"content":{"rendered":"<div>\n<p><b>J Immunol<\/b>. 2025 May 22:vkaf101. doi: 10.1093\/jimmun\/vkaf101. Online ahead of print.<\/p>\n<p><b>ABSTRACT<\/b><\/p>\n<p>Higher circulating SARS-CoV-2 IgG titers correlate with SARS-CoV-2 ex vivo viral neutralization, but how well this translates to clinical protection in the real-world setting is unclear. In a prospective cohort study, we enrolled 44 SARS-CoV-2 negative, confirmed SARS-CoV-2 close contacts. Receptor-binding domain (RBD) and full-spike IgG and SARS-CoV-2 memory B-cell frequencies were measured at exposure, and participants were serially tested for incident infection over 14 days. Those who developed SARS-CoV-2 infection had significantly lower RBD titers, but not memory B-cell frequencies. An RBD IgG titer &gt;6321 BAU\/ml was associated with a reduced SARS-CoV-2 acquisition risk (HR 0.32, 95% CI 0.13-0.81), while an RBD IgG titer &gt;456 BAU\/ml was associated with a reduced moderate or severe COVID-19 risk (HR 0.15, 95% CI 0.03-0.81), identifying this threshold as a correlate of protection.<\/p>\n<p>PMID:<a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/40405410\/?utm_source=WordPress&amp;utm_medium=rss&amp;utm_content=2985117R&amp;ff=20250523065131&amp;v=2.18.0.post9+e462414\">40405410<\/a> | DOI:<a href=\"https:\/\/doi.org\/10.1093\/jimmun\/vkaf101\">10.1093\/jimmun\/vkaf101<\/a><\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>J Immunol. 2025 May 22:vkaf101. doi: 10.1093\/jimmun\/vkaf101. Online ahead of print. ABSTRACT Higher circulating SARS-CoV-2 IgG titers correlate with SARS-CoV-2 ex vivo viral neutralization, but how well this translates to clinical protection in the real-world setting is unclear. In a prospective cohort study, we enrolled 44 SARS-CoV-2 negative, confirmed SARS-CoV-2 close contacts. Receptor-binding domain (RBD) &#8230; <a title=\"Specific thresholds of circulating antibody titers predict against infection and reduced disease severity in SARS-CoV-2 close contacts\" class=\"read-more\" href=\"https:\/\/inmuno.es\/index.php\/2025\/05\/23\/specific-thresholds-of-circulating-antibody-titers-predict-against-infection-and-reduced-disease-severity-in-sars-cov-2-close-contacts\/\" aria-label=\"Read more about Specific thresholds of circulating antibody titers predict against infection and reduced disease severity in SARS-CoV-2 close contacts\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42,71],"tags":[],"class_list":["post-33313","post","type-post","status-publish","format-standard","hentry","category-publicaciones","category-the-journal-of-immunology"],"_links":{"self":[{"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/posts\/33313","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/comments?post=33313"}],"version-history":[{"count":0,"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/posts\/33313\/revisions"}],"wp:attachment":[{"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/media?parent=33313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/categories?post=33313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inmuno.es\/index.php\/wp-json\/wp\/v2\/tags?post=33313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}