A Different Type of COVID-19 Antibody Test
IMMUNO-COV tells you whether you have neutralizing antibodies,
antibodies that can block the COVID-19 virus from infecting cells.
Other antibody tests, such as ELISAs or Point of Care tests, can also
detect the antibodies that recognize the COVID-19 virus.
However, those tests cannot tell you how effective your
antibodies are at blocking the virus from infecting cells.
In contrast to other antibody tests, the IMMUNO-COV assay specifically measures antibodies in the blood that can block infection by SARS-Co-V-2, the virus that causes COVID19. One of the critical ways the immune system fights a SARS-CoV-2 infection is to make a huge number of antibodies which recognize and bind to the surface of the virus in many different ways and at many different sites. A small subset of those antibodies (so-called neutralizing antibodies) can actually prevent the virus from infecting new cells. For many other viruses (e.g. measles), neutralizing antibodies are known to protect against infection because they make it very difficult for a virus entering the upper airways to get a foothold and to spread elsewhere in the body
The IMMUNO-COV test uses an innocuous virus that mimics SARS-CoV-2 and detects antibodies in your blood that can recognize and stop the mimic virus from infecting new cells. Neutralizing antibodies are detectable in the blood typically 14 days after the onset of infection and their levels vary widely from person to person.
HOW THE IMMUNO-COV TEST WORKS - FROM INFECTION TO ANALYSIS
Contact with SARS coronavirus 2 (SARS-CoV-2).
SARS-CoV-2 enters an exposed person’s body.
Spike proteins on the outer surface of SARS-CoV-2 bind to receptors on certain cells, triggering virus entry into the cells and subsequent virus replication.
After replication, new virus is released from the cell. The body’s immune response includes production of antibodies to stop further virus spread.
All of these newly produced antibodies recognize the virus, but only neutralizing antibodies block the virus from entering cells, thereby preventing infection.
Infected patients can be either symptomatic or asymptomatic.
The gene encoding the SARS-CoV-2 spike protein is engineered into a harmless Vesicular Stomatitis Virus (VSV).
Cells express complementary pieces of a reporter protein. When cells fuse, the complementary pieces come together which causes the cells to glow.
Infection with surrogate VSV (expressing SARS-CoV-2 spike protein) causes cells to fuse and glow.
A sample of your blood is incubated with the surrogate virus and then combined with the assay cells.
If your blood contains neutralizing antibodies, they will prevent the surrogate virus from infecting and fusing the cells, so the cells will not glow.
If your blood only contains non-neutralizing antibodies, the surrogate virus will infect cells, causing them to fuse and glow.
Scientific and Research Applications
IMMUNO-COV was developed to the address the urgent need to know if an individual who has recovered from COVID-19 has protective neutralizing antibodies against the virus. Since its launch, supporting scientific and research communities in their work has been our priority. This priority continues, even as we broaden IMMUNO-COV’s availability, to be a critical segment for us to support in their continued work on these and other applications:
- Assessing neutralizing antibody levels in potential donors of COVID-19 convalescent plasma for treatment of patients infected with SARS-CoV-2 (plasma with high neutralizing antibody titers is preferred)
- Evaluating the relative effectiveness of SARS-CoV-2 vaccine candidates in clinical trials
Please contact us to discuss how you can access the IMMUNO-COV assay.