Antibodies and COVID-19

The immune system is powerful. Creating a defense team of antibodies to actively fight of any and all invaders is one of its main strengths and abilities. However, not all antibodies are the same. They are actually very different and unique and your body has millions and millions of specific antibodies. Based on the different heavy chain in the Fc region of the antibody can determine at what point a person has been infected or is currently. These are called the IgG and IgM antibodies. IgM is present in greater quantities during the primary response before memory and class switching take place; whereas, IgG is present during the secondary response after increased affinity and linking of the CD40L to CD40 receptor on the B-cell.

A company in China called Dynamiker Biotechnologies has created a test in order to reveal which antibody a person has and to determine if they have asymptomatically carried the virus and have adapted an immune response that could last for years. According to their website, the test is 92% accurate and only takes 10 minutes to get the results. With the prick of a finger and collection of blood, you can determine if one is IgM +/- and IgG +/-. The results are as follows:

IgM + / IgG – : is assumed to be an acute infection but needs retesting in a week; this can also be a false positive which would also need retesting

IgM + / IgG + : can be considered as an acute infection

IgM – / IgG + : is a sign of a previous infection and needs to continually to monitor, if the IgG level increases than the infection is either acute or very recent.

IgM – / IgG – : there has been no infection

Other companies have come up with similar tests that will likely be administered in places with people returning to work once the communities are sent out of shelter in place orders. With the presence of IgG, it is able to be determined that people have been infected recently with COVID-19 but have recovered.

According to author Jonathan Mintz in his article, about the new antibody tests. This could be a huge opportunity for healthcare workers who have been sent home with symptoms to return to work as they are now immune to the virus. Additionally, people with antibodies could begin to donate their blood to those without them who are fighting to virus in order to aide their immune systems in detecting and killing the pathogen.