SARS-CoV-2 IgG ELISA Kit (S Protein, Spike Protein)

Application: The human IgG antibody detection kit with indirect ELISA method is used for qualitative detection or semi-quantitative measurement of human IgG antibodies specific for the SARS-CoV-2 spike protein, S1 subunit in serum or plasma.Accession: QHD43416.1Predicted molecular mass: 160.7 kDa.Endotoxin: Less than 1 EU per ug by the LAL method.Formulation: The recombinant SARS-CoV-2 Spike S protein was lyophilized from 0.22 um filtered solution in 20 mM PB (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization.Purity: > 95% by PAGE under reduced condition, and SEC-HPLC.Shipping: The product is shipped with ice packs. Upon receipt, store it immediately at the temperature recommended below.Stability & Storage:Use a manual defrost freezer and avoid repeated freeze-thaw cycles.1 month from date of receipt, 2 to 8°C as supplied.

Background

The SARS-CoV-2 spike (S) glycoprotein plays the most important roles in viral attachment, fusion and entry. The virus causing Coronavirus Disease 2019 (COVID-19) was named 2019 novel coronavirus (2019-nCoV) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). There are four major structural proteins in SARS-CoV-2, spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins.

There are two subunits, S1 and S2, in the SARS-CoV-2 spike (S) glycoprotein. The furin cleavage site at the boundary between the S1/S2 subunits is processed during biogenesis and sets this virus apart from SARS-CoV and SARS-related CoVs. The S1 subunit, the N-terminal 14-685 amino acids of S protein, contains N-terminal domain (NTD), receptor binding domain (RBD), and receptor binding motif (RBM). The C-terminal S2 subunit contains fusion peptide (FP), heptad repeat 1 (HR1), heptad repeat 2 (HR2), transmembrane domain (TM), and cytoplasmic domain (CP). The SARS-CoV and SARS-CoV-2 S proteins mediate viral entry into host cells by binding to a host receptor, angiotensin-converting enzyme 2 (ACE2), through the receptor-binding domain (RBD) in the S1 subunit, and then fusing the viral and host membranes through the S2 subunit.