Liposome-based high-throughput and point-of-care assays toward the quick, simple, and sensitive detection of neutralizing antibodies against SARS-CoV-2 in patient sera

• DOI: 10.1007/s00216-023-04548-3
• Publication Date: 2023-02-09T14:24:58Z
• Authors: Simon Streif; Patrick Neckermann; Clemens Spitzenberg; Katharina Weiss; Kilian Hoecherl; Kacper Kulikowski; Sonja Hahner; Christina Noelting; Sebastian Einhauser; David Peterhoff; Claudia Asam; Ralf Wagner; Antje J. Baeumner
• Keywords: Polyclonal antibodies; Streptavidin

Abstract The emergence of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) in 2019 caused an increased interest neutralizing antibody tests to determine the immune status population. Standard live-virus-based neutralization assays such as plaque-reduction or pseudovirus cannot be adapted point-of-care (POC). Accordingly, quantifying competitive binding inhibition angiotensin-converting enzyme (ACE2) receptor receptor-binding domain (RBD) SARS-CoV-2 by antibodies have been developed. Here, we present a new platform using sulforhodamine B encapsulating liposomes decorated with RBD foundation for development both fluorescent, highly feasible high-throughput (HTS) and POC-ready assay. RBD-conjugated are incubated serum subsequently immobilized ACE2-coated plate mixed biotinylated ACE2 used test strip streptavidin line, respectively. Polyclonal human were shown cause complete inhibition, while S309 CR3022 monoclonal only partial proving functionality Both formats, HTS POC assay, then tested 20 sera containing varying titers antibodies, control panel including prepandemic reconvalescent from infections other than SARS-CoV-2. correlated well standard ( r = 0.847 0.614 format). Furthermore, excellent correlation 0.868) between formats was observed. flexibility afforded signaling agents different dyes sizes can hence utilized future broad range multianalyte diagnostics. Graphical abstract