COVID-19 Antibodies
What is COVID-19?
COVID-19 is a disease caused by a novel coronavirus (CoV) SARS-CoV-2 also known as 2019-nCoV. The disease was first discovered from Wuhan, China and is spreading worldwide with 2050 laboratory-confirmed infections and 56 fatal cases reported on January 26,2020[i]. The World Health Organization (WHO) has declared a global health emergency to gather resources and remedy this threat.
COVID-19 Coronavirus Background
There are four coronavirus genera[ii]: alphacoronavirus, betacoronavirus, gammacoronavirus, and deltacoronavirus. COVID-19's coronavirus SARS-CoV-2 belongs to the Betacoronavirus genus originating from bats. Betacoronaviruses can infect mammals, are zoonotic pathogens, and can cause severe respiratory disease in humans. Other viruses in this family are SARS coronavirus and MERS coronavirus. SARS-CoV-2 has approximately 79% sequence identity to SARS-CoV and 50% to MERS-CoV.[iii] In addition, homology modeling shows SARS-CoV-2 has a similar receptor-binding domain structure as SARS-CoV which suggests SARS-CoV-2 uses ACE2 receptor in humans for infection.
SARS-CoV-2 Structure
The structure[iv] of SARS-CoV-2 consists of the following: a spike protein (S), hemagglutinin-esterease dimer (HE), a membrane glycoprotein (M), an envelope protein (E) a nucleoclapid protein (N) and RNA as seen in the figure below.
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Spike protein (S) is heavily glycosylated, utilizes an N-terminal signal sequence to gain access to the ER and mediate attachment to host receptors. It is the largest structure and makes the distinct spikes on the surface of the virus. For most coronaviruses, S protein is cleaved by a host cell furin-like protease into two separate polypeptides S1 and S2. RNA is the genome of the virus.
Nucleocapsid protein (N) binds to RNA in vitro and is heavily phosphorylated. N proteins binds the viral genome in a beads on a string type conformation. This protein likely helps tether the viral genome to replicase-transcriptase complex (RTC), and subsequently package the encapsulated genome into viral particles. Envelope protein (E) is found in small quantities in within the virus. It is most likely a transmembrane protein and with ion channel activity. The protein facilitates assembly and release of the virus and has other functions such as ion channel activity. It is not necessary for viral replication but it is for pathogenesis. Membrane protein (M) is the most abundant structural protein. It does not contain signal sequence and exists as a dimer in the virion. It may have two different conformations to enable it to promote membrane curvature as well as bind to nucleocapsid. Hemagglutinin-esterase dimer protein (HE) is present in a subset of betacoronaviruses. The protein binds sialic acids on surface glycoproteins. The protein activities are thought to enhance S protein-mediated cell entry and virus spread through the mucosa. |
ProSci Products
To support the efforts of researchers worldwide in understanding and combating this new health threat, ProSci Scientists evaluated our SARS-CoV antibodies and determined the percentage of identity and holology between the immunogen used to develop these antibodies and the SARS-CoV-2 sequences available as of February 15, 2020. Higher percentage of identity and homology suggests reactivity to SARS-CoV-2. Trial size antibodies are available for testing and a large batch is available to ensure lot to lot consistancy.
SARS-CoV-2 Spike Antibodies
| Product | Cat. No. | Host | Application | Reactivity | % Identity | % Homology | Blocking Peptide |
|---|---|---|---|---|---|---|---|
| SARS Spike Antibody | 3525 | Rabbit | ELISA | Virus | 100% | 100% | Blocking Peptide |
| SARS Spike Antibody | 3223 | Rabbit | ELISA | Virus | 65% | 88% | Blocking Peptide |
| SARS Spike Antibody | 3221 | Rabbit | ELISA | Virus | 56% | 69% | Blocking Peptide |
| SARS Spike Antibody | 3225 | Rabbit | ELISA | Virus | 38% | 56% | Blocking Peptide |
| SARS Spike Antibody | 3219 | Rabbit | ELISA | Virus | 14% | 29% | Blocking Peptide |
SARS-CoV-2 Membrane Antibodies
| Product | Cat. No. | Host | Application | Reactivity | % Identity | % Homology | Blocking Peptide |
|---|---|---|---|---|---|---|---|
| SARS Matrix Antibody | 3527 | Rabbit | ELISA | Virus | 86% | 93% | Blocking Peptide |
| SARS Matrix Antibody | 3529 | Rabbit | ELISA | Virus | 80% | 93% | Blocking Peptide |
SARS-CoV-2 Envelope Antibodies
| Product | Cat. No. | Host | Application | Reactivity | % Identity | % Homology | Blocking Peptide |
|---|---|---|---|---|---|---|---|
| SARS Envelope Antibody | 3531 | Rabbit | ELISA | Virus | 100% | 100% | Blocking Peptide |
| SARS Envelope Antibody | 3533 | Rabbit | ELISA | Virus | 82% | 91% | Blocking Peptide |
For SARS-CoV-2 receptor reagents, check out our ACE2 products! In addition to all our COVID-19 related antibody reagents, we also offer custom antibody services for polyclonal, monoclonal, and single domain antibodies.
[i] Zhou, P. et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature https:// doi.org/10.1038/s41586-020-2012-7 (2020)
[ii] Fan, Y.; Zhao, K.; Shi, Z.-L.; Zhou, P. Bat Coronaviruses in China. Viruses 2019, 11, 210. https://doi.org/10.3390/v11030210
[iii] Lu R, Zhao X, Li J, et al. Genomic characterization and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. The Lancet. Published online January 29, 2020. https://doi.org/10.1016/ S0140-6736(20)30251-8
[iv] Fehr AR, Perlman S. Coronaviruses: an overview of their replication and pathogenesis. Methods Mol Biol. 2015;1282:1–23. https://doi.org/10.1007/978-1-4939-2438-7_1
