The COVID-19 pandemic continues. One of the problems in finding vaccines against COVID-19 is their possible reverse effect, the so-called antibody-mediated enhancement of viral infection [1]. There is also increasing evidence that SARS-CoV-2 can selectively kill insulin-producing cells, thus causing diabetes [2]. And antibodies from the blood plasma of those who got over COVID-19 may be the first available treatment for severe cases of this disease [3].