{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T19:37:23Z","timestamp":1770925043527,"version":"3.50.1"},"reference-count":32,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T00:00:00Z","timestamp":1766448000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"Korea Health Technology R&D Project of the Korea Health Industry Development Institute","award":["HI22C0360000023"],"award-info":[{"award-number":["HI22C0360000023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The rapid evolution of SARS-CoV-2 presents substantial challenges to maintaining diagnostic accuracy. Single-domain antibodies (variable domains of camelid heavy-chain antibodies, VHHs), commonly referred to as nanobodies, are attractive tools for diagnostic applications due to their high specificity, stability, affinity and expression yield. In this study, three high-affinity VHHs that recognize the receptor-binding domain (RBD) of the SARS-CoV-2 BA.2 variant were isolated from a large na\u00efve alpaca VHH phage display library. These nanobodies exhibited nanomolar affinities and high thermal stability. Notably, reformatting one VHH into a bivalent VHH-Fc fusion construct, K115.2-Fc, enhanced binding affinity 24-fold, achieving an equilibrium dissociation constant of 68.3 picomolar. Functional characterization demonstrated that K115.2-Fc cross-reacted with the Wuhan SARS-CoV-2 RBD and multiple variants, including Alpha, Beta, Gamma, Delta, Kappa, BA.1, BA.2, and BA.4\/5. In indirect enzyme-linked immunosorbent assay, K115.2-Fc detected full-length spike protein with a limit of detection of 8.1 pM. Moreover, it enabled sensitive detection in western blotting and flow cytometry, highlighting its applicability across diverse diagnostic applications. Collectively, these findings identify K115.2-Fc as a promising candidate with potential for SARS-CoV-2 diagnostic utility.<\/jats:p>","DOI":"10.1093\/protein\/gzag001","type":"journal-article","created":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T12:20:39Z","timestamp":1768825239000},"source":"Crossref","is-referenced-by-count":0,"title":["Rapid isolation and characterization of high-affinity single-domain antibodies for broad-Spectrum detection of SARS-CoV-2 variants"],"prefix":"10.1093","volume":"39","author":[{"given":"Ah Hyun","family":"Cho","sequence":"first","affiliation":[{"name":"Department of Biopharmaceutical Chemistry, Kookmin University , 77 Jeongneung-ro, Seongbuk-gu, Seoul 02707 ,","place":["Republic of Korea"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hee Eon","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biopharmaceutical Chemistry, Kookmin University , 77 Jeongneung-ro, Seongbuk-gu, Seoul 02707 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