COVID-19 An Emerging Global Threat.
Coronavirus disease 2019 (COVID-19), formerly known as 2019-nCoV acute respiratory disease, is an infectious disease caused by SARS-CoV-2, a virus closely related to the SARS virus, originated from the Wuhan region of Hubei province in China late in 2019 (1).
COVID-19 Spike Protein (S1+S2) Antibody
COVID-19 invades cells through spike protein-mediated binding human airway epithelial cell surface receptor Angiotensin-converting enzyme 2 (ACE2). Spike protein also mediates the fusion of host and viral cell membrane to begin infection (2). Spike protein is the major target for neutralizing antibodies and vaccine development (3).
Protein modeling suggests that there is a strong interaction between the Spike protein receptor-binding domain and its host receptor angiotensin-converting enzyme 2 (ACE2), which regulate both the cross-species and human-to-human transmissions of COVID-19 (4). A recent study has shown that the SARS-CoV-2 spike protein binds ACE2 with a higher affinity than SARS-CoV spike protein (5).
COVID-19 spike protein gene has been sequenced and the protein structurally modeled. The spike protein is a large type I transmembrane protein containing two subunits, S1 (in red below) and S2 (in green below). S1 (red) contains a receptor-binding domain, which is responsible for recognizing the cell surface receptor. S2 (green) contains the transmembrane domain, which anchors the spike protein to the viral envelope and also has the elements needed for membrane fusion to initiate viral entry into the host cell.
The cloned extracellular domain of COVID-19 spike protein has been expressed using an insect cell line and purified via a C terminal polyhistidine tag. The cloned COVID-19 spike protein we use has been demonstrated to bind recombinant human ACE2, its major airway epithelial cell target.
COVID-19 Nucleocapsid Antibody
The coronavirus nucleocapsid is a structural protein that forms complexes with genomic RNA, interacts with the viral membrane protein during virion assembly and plays a critical role in enhancing the efficiency of virus transcription and assembly.
Full-length COVID-19 virus S gene (nucleoprotein) was cloned, expressed and purified from E. coli via a C terminal polyhistidine tag.
Click here to view anti-nucleocapsid antibody (ab-131-300)
- Gorbalenya. bioRxiv: 2020.
- Belouzard et al. Viruses. 2012;4(6):1011-33.
- Lee et al. J Virol. 2006;80(8):4079-87.
- Wan et al. J Virol. 2020.
- Wrapp et al. Science. 2020.