Memory B cells and serum immunoglobulins are associated with disease severity and mortality in patients with COVID-19
Fatih Çölkesen, Fatih Çölkesen, Esma Kepenek Kurt, Hülya Vatansev, Celalettin Korkmaz, Fatma Çölkesen, Fatma Çölkesen, Fatih Yücel, Eray Yıldız, Recep Evcen, Filiz Sadi Aykan, Mehmet Kılınç, Gökhan Aytekіn, Bahadır Feyzioğlu, Metin Doğan, Şevket Arslan, Turgut Teke, Sevgi Keleş, İsmail Reisli
Abstract
PURPOSE OF THE STUDY: The aim of this study was to investigate the relationship of B cell-mediated immunity with disease severity and mortality in patients with COVID-19. STUDY DESIGN: In this retrospective cohort and single-centre study, 208 patients with laboratory-confirmed COVID-19 were recruited. A COVID-19 severity score, ranging from 0 to 10, was used to evaluate associations between various factors. Serum immunoglobulin levels and the number of cells in B lymphocyte subsets were measured and their association with disease severity and mortality in patients with COVID-19 examined. RESULTS: The median age of the patients was 50 (35-63) years and 88 (42%) were female. The number of deceased patients was 17. The median COVID-19 severity score was 8 (6-8) in deceased patients and 1 (0-2) in survivors. Deceased patients had significantly lower levels of total B lymphocytes, naive B cells, switched memory B cells, and serum IgA, IgG, IgG1 and IgG2 than recovered patients (all p<0.05). In addition, a significant negative correlation was found between the number of these parameters and COVID-19 severity scores. Decrease in the number of total B cells and switched memory B cells as well as lower serum IgA, IgG and IgG1 levels were independent risk factors for mortality in patients with COVID-19. CONCLUSION: In the present study, the prognosis of patients with COVID-19 was shown to be associated with the B cell subset and serum immunoglobulin levels.