Coronavirus disease 2019 and antinuclear autoantibody production

Aim: Due to the motif similarity of the SARS-CoV-2 virus to the body's self-antigens, there is a possibility of producing autoantibodies in both coronavirus disease 2019 (COVID-19) and vaccinated individuals. Anti-nuclear antibodies (ANA), the most common of these autoantibodies, are thought to be associated with tissue damage and poor prognosis. The aim of the current thesis study is to comprehensively examine the COVID-19-vaccines/ANA relationship with parameters such as post-disease course, symptom severity and the effect of vaccine types (conventional and mRNA) and to reveal the prevalence of COVID-19-related ANA in our country for the first time. Meterial and Method: The study was designed retrospectively and three separate ELISA test kits (anti-dsDNA, anti-ENA and anti-Hep-2 nucleus test) were developed for the analyses, each measuring a different ANA subgroup. Among the antigens used in the tests, dsDNA and ENA were extracted from calf thymus, and the nucleus was isolated from the Hep-2 cell line in cell culture. Multifaceted validation analyzes of the developed kits were performed, and when evaluated in terms of both comparison with commercial kits and compatibility with diseases, it was determined that they were in compliance with international norms. With five different experimental designs; (i) course of ANA formation after the disease (n = 33, first 2 months, 15 days apart), (ii) effect of symptom severity on ANA formation (mild, n = 22; severe, n = 11), (iii) single type of vaccine administration (Sinovac, n=57 or mRNA, n=34) and (iv) vaccine combinations (receiving both types of vaccines once, n=45) on ANA positivity in people who have not had COVID-19 were examined and (v) the prevalence of ANA (n=400) was determined in those who had COVID-19. Results: In the post-COVID-19 period, the course of ANA formation increased cumulatively in the first 2-month period (p<0.05) and there was no relationship between symptom severity and ANA positivity rate (mild; 36.4% - severe; 54.5%) (p>0.05) . It was determined that the Sinovac vaccine cumulatively increased the rate of ANA depending on the number of vaccinations compared to the pre-vaccine period (p<0.05), but the mRNA vaccine did not affect the formation of ANA (p>0.05). Anti-dsDNA antibody was found to be high in people who received both vaccines (p<0.05). In the prevalence study, it was determined that the ANA rate increased 2.5 times in those who had COVID-19 compared to healthy people who did not have COVID-19 (healthy; 17.5% – COVID-19; 43.5%) (p<0.05). Conclusion: It has been observed that one in every two-three people with COVID-19 is positive for ANA, and it has been determined that the viral particles contained in the vaccine trigger the formation of ANA. When all the findings were evaluated together, it was concluded that SARS-CoV-2 is an autoimmune virus and can trigger immune reactions. Keywords: COVID-19, coronavirus vaccine, antinuclear autoantibody, ANA