ABO blood group type does not influence the level of SARS-CoV-2 antibody response in convalescent plasma donors

The association of ABO blood group types with the COVID-19 disease has been confirmed by several studies, with the blood group A-type patients being more susceptible and prone to more severe clinical course of disease. Similarly, some authors explored the association of ABO-types and the levels of anti-SARS-CoV-2 antibodies in convalescents. The recent reports mostly support a theory that non-O blood group convalescents present with higher levels of anti-SARS-CoV-2 antibodies. Since these findings were based on small convalescent cohorts, we quantified the anti-SARS-CoV-2 antibodiy levels in four larger cohorts of total 3185 convalescent plasma donors with three commercial serological tests and one standard neutralizing antibody test. The majority of donors had undergone a mild form of disease and the median time of sampling was 66 days after the onset of COVID-19 symptoms. None of the antibody quantitation methods showed an association of the ABO blood group types with the level of anti-SARS-CoV-2 antibodies. The same result is evident in the group of vaccinated individuals (n=370) as well as in the groups stratified into three post-COVID-19 periods (0-60, 60-120, and 120-180 days). In conclusion we can state that the ABO blood group type does not influence the level of SARS-CoV-2 antibody response in COVID-19 convalescent plasma donors.