Autoimmune anti-DNA antibodies predict disease severity in COVID-19 patients

COVID-19 can lead to severe disease and death, however the mechanisms of pathogenesis in these patients remain poorly understood. High levels of autoimmune antibodies have been observed frequently in COVID-19 patients but their specific contribution to disease severity and clinical manifestations remain unknown. We performed a retrospective study of 115 COVID-19 hospitalized patients with different degrees of severity to analyze the generation of autoimmune antibodies to common antigens: a lysate of erythrocytes, the lipid phosphatidylserine (PS) and DNA. High levels of IgG autoantibodies against erythrocyte lysates were observed in a large percentage (up to 41%) of patients. Anti-DNA antibodies determined upon hospital admission correlated strongly with later development of severe disease, showing a positive predictive value of 89.5% and accounting for 22% of total severe cases. Statistical analysis identified strong correlations between anti-DNA antibodies and markers of cell injury, coagulation, neutrophil levels and erythrocyte size. Anti-DNA autoantibodies may play an important role in the pathogenesis of COVID-19 and could be developed as a predictive biomarker for disease severity and specific clinical manifestations.

Autoimmunity to the Lung Protective Phospholipid-Binding Protein Annexin A2 Predicts Mortality Among Hospitalized COVID-19 Patients

BackgroundAnnexin A2 is a phospholipid-binding protein involved in fibrinolysis, cell membrane stabilization and repair, and ensuring the integrity of the pulmonary microvasculature. Given the autoantibodies observed in COVID-19 and that Annexin A2 is a known target of antiphospholipid antibodies, we studied autoimmunity directed against Annexin A2 among hospitalized COVID-19 patients. MethodsWe used ELISA to identify the levels of IgG autoantibodies recognizing Annexin A2 and A5 among 86 hospitalized cases of COVID-19. Using logistic regression, we analyzed the association between anti-Annexin A2 and A5 antibody levels with mortality after adjusting for age, sex, race and key comorbidities. ResultsWe found higher average levels of anti-Annexin A2 antibodies among hospitalized COVID-19 patients that died when compared with non-critical hospitalized COVID-19 patients (p-value = 0.006) and critically ill COVID-19 patients (p-value = 0.04). No significant differences in anti-Annexin A5 antibody levels were identified. Regression analysis showed that anti-Annexin A2 antibody levels as measured in relative units strongly predicted mortality with an odds ratio of 9.3 (95% CI: 1.9 to 44.6, p=0.005). In contrast, anti-Annexin A5 antibody levels were not associated with higher mortality (95% CI: 0.5 to 15.2, p=0.22). ConclusionsWe determined that anti-Annexin A2 antibodies were elevated among hospitalized COVID-19 patients and these levels predicted mortality. It is known that inhibition of Annexin A2 induces systemic thrombosis, cell death, and non-cardiogenic pulmonary edema. Autoimmunity to Annexin A2 is a potential mechanism that may explain the key clinical findings of severe COVID-19.