After the start of the coronavirus pandemic (Covid-19)and its devastating impact on the economy, the tycoon Elon musk decided to launch his own investigation among employees of Spacex in an attempt to track the spread of the virus in the company Y study the immune response.
In the study, led by experts from the MGH Ragon Institute, MIT Y Harvard, participated 4,300 volunteers, all workers of the firm aerospace. His follow-up began in April 2020 and included monthly anti-RBD (receptor-binding domain) IgG antibody tests and detailed analysis of symptoms.
The researchers published the results in the middle of this month and see their work as an important step in better understanding the development of immunity natural to SARS-CoV-2 and the reactions of the immune system in the asymptomatic cases.
What did they discover?
A total of120 participantsthey turned outseroconverts, or in other words, they presented antibodies against SARS-CoV-2. The majority of them, 73 people representing 61% of the sample, showed no symptoms related to the disease, as the loss of smell or the taste, cough, fever or shaking chills.
On the other hand, the scientists observed that people who developed a higher number of antibodies they had stronger symptomseven when the illness was mild. Although, both the asymptomatic and those who suffered from Covid-19 with symptoms had antibodies, the highest titers were typical of cases with more signs of discomfort.
The experts also detected the presence ofT cellsat 83% of people who showed higher amounts of antibodies (10 out of 12), while in the group of volunteers with the lowest amount, T cells were only detected in 10% of the cases (1 of 10).
« These findings show that SARS-CoV-2 specific T cells are not detectable in all infected individuals Y are not selectively potentiated between individuals with less robust humoral immune responses, « the researchers wrote. » However, the data suggest that both T and B cells evolve in a coordinated way« they added.
How to measure immunity
In early fall 2020, researchers were still unsure that asymptomatic cases could develop long-lasting antibodies, nor if they were capable of neutralizing or killing the virus.
Now, they have come to the conclusion that there is a certain threshold for antibodies that can provide long-lasting protection against coronavirus, as well as explain the cases of reinfection through the number of antibodies below that level, which has yet to be calculated and requires more research focused on reinfection.
« Once a certain threshold of these antibodies, it’s like i know turn on a switch and we could observe the executive functions of antibodies« explainedYannic Bartsch, one of the study authors, after noting that « these functions were not observed in individuals with lower titers, and the level of protection against reinfection in these people is uncertain. »
Galit alter, who led the investigation, explained that his work shows that « It is not just the presence or absence of antibodies what matters, but the amount and type of antibodiescould play a determining role in the development of a protective immune response« In addition, the scientist commented toThe Wall Street Journalthat « people can have antibodies, but this does not necessarily mean that they will be immune. »