Hope for Coronavirus: Natural Antibodies

Well, here we are in April 2020, still dealing with the novel coronavirus, a.k.a COVID-19. While we have never faced anything like this before, the scientific community has done its best to develop new tests to determine how we can best fight this invisible enemy. One of the newest developments has been the use of antibody testing for those who have had the virus. Two of the antibodies that these tests look for are very familiar to those of us in Dr. Cramer’s Medical Microbiology: IgM and IgG. I’m so glad that we recently covered these antibodies in class so that we can understand just what the presence of these antibodies means.

We learned in class that when B cells are only partially activated (they have only received Signal 1), they can only make IgM antibodies, which are not very specific antibodies. According to a New York Times article, IgM levels sharply increase a few days after one has been infected with coronavirus, and IgG levels are at their highest around 28 days. As microbiology students, we can make the connection that if someone had only IgM antibody titers, they are early in the stage of infection. The body would then start to make more and more IgG after the B cells receive their second signal, and eventually IgM would stop being produced. This would be a gradual process.

But what would it mean if someone had a primarily IgG titer, or they were IgG positive? According to an article from Science News, after about 10 days of being infected with coronavirus, you are not likely to infect anyone else. This means that at 28 days when IgG levels are at their highest, they are in the late stage of infection, and probably won’t infect others. So, if we could determine who is IgG positive, it would be an absolute game changer. We could try to cure those fighting coronavirus using antibodies in the blood of those who have already become healthy again. My hope is that recovered individuals will volunteer to have their blood tested, and that antibodies are the answer to helping coronavirus patients!