Description
Key facts
Detection method:Colorimetric,
Sample types:Citrate plasma, EDTA Plasma, Lithium Heparin Plasma, Serum,
Assay type:Semi-quantitative,
Assay Platform:Microplate
Product details:
SARS-CoV-2 IgG ELISA Kit (ab275300) is an Enzyme-Linked Immunosorbent Assay (ELISA) intended for semi-quantitative detection of IgG antibodies to SARS-CoV-2 in human serum or plasma collected in potassium EDTA, sodium citrate or lithium heparin.
This kit is intended for use as an aid in identifying individuals with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection. Understanding the timing, duration and effectiveness of humoral immune responses in individuals previously infected with SARS-CoV-2 will be important for conducting vaccine and epidemiological research. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity.
Results are for the detection of SARS-CoV-2 antibodies. IgG antibodies to SARS-CoV-2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. Individuals may have detectable virus present for several weeks following seroconversion.
The sensitivity of SARS-CoV-2 IgG ELISA early after infection is unknown. Negative results do not preclude acute SARS-CoV-2 infection.
False positive results for SARS-CoV-2 IgG ELISA may occur due to cross-reactivity from pre-existing antibodies to SARS-CoV 1 or other possible causes.
Abcam offers a
variety of tools
used to help understand and accelerate infectious disease research, including SARS-CoV-2, the coronavirus that causes COVID-19.
This kit provides for an indirect ELISA, in which a recombinant receptor binding domain (RBD) of the Spike1 protein of SARS-CoV 2 is coated on the wells of the microtiter plate. Antibodies to SARS-CoV-2 RBD when present in the test sample bind specifically to the RBD protein. After sample binding, unbound proteins and molecules are washed off, and a HRP-conjugated detection antibody is added to the wells to bind to the captured anti-SARS-CoV2 IgG antibodies. The chromogenic substrate TMB (3,3',5,5'tetramethylbenzidine) is then added. This reaction produces a blue product, which turns yellow when the reaction is terminated by addition of dilute sulfuric acid. The absorbance of the yellow product at 450 nm, corrected for plate imperfections by subtracting the absorbance at 570 nm, is proportional to the amount of RBD-specific anti-SARS-CoV-2 IgG present in the sample.
After determining that the values for the Positive Control and Negative Control are valid and acceptable by comparing them to the value for the Calibrator, values for samples are compared to the Calibrator to generate a ratio. Ratios above a cutoff indicate positive samples and values below a cutoff indicate negative samples.
Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions-+4°C, Appropriate long-term storage conditions-+4°C, Storage information-+4°C
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
The SARS-CoV-2 Spike Glycoprotein S1 also known as the G10 spike or glycoprotein spike plays an important role in allowing the virus to attach and enter host cells. This protein with a mass of approximately 180 kDa is located on the surface of the virus and forms the outer spikes observed in coronaviruses. Expression of the spike glycoprotein is in virus-infected cells where it facilitates the interaction with host cell receptors. The S1 subunit includes a receptor-binding domain that specifically binds to the human angiotensin-converting enzyme 2 (ACE2) receptors initiating the infection process.
Biological function summary
The spike glycoprotein S1 mediates the fusion of the viral and cellular membranes which is necessary for viral entry. It forms part of a larger trimeric complex comprising S1 and S2 subunits. This complex undergoes conformational changes that drive the membrane fusion process. The glycoprotein contains multiple glycosylation sites which help shield the virus from the host immune response. The proper function and presentation of this glycoprotein are critical for efficient viral spread and infection establishment.
Pathways
The spike glycoprotein S1 is integral to the viral infection pathway and host immune evasion. It interacts with the renin-angiotensin system by binding to the ACE2 receptor disrupting normal receptor activity. This interaction not only facilitates viral entry but also impacts the homeostatic functions typically mediated by ACE2 which include blood pressure regulation. Additionally the spike protein is involved in downstream activation of immune signaling pathways including those related to inflammation and cytokine production which may involve proteins such as IL-6.
Infection with the spike glycoprotein S1 is directly related to COVID-19. The binding to ACE2 receptors is linked to the pathology of the disease contributing to respiratory symptoms and in severe cases acute respiratory distress syndrome (ARDS). Through the IL-6 signaling pathway the spike protein is indirectly connected to cytokine release syndrome often observed in severe COVID-19 cases. This connection highlights the importance of targeting this glycoprotein for potential therapeutic interventions and diagnostics such as ELISA SARS-CoV-2 tests and the development of anti-spike antibodies available on platforms like antispark.com for research and clinical purposes.
