Transforming growth factor beta 1 (TGF- β 1) in COVID-19 patients: relation to platelets and association with the disease outcome

Transforming growth factor beta (TGF- β ) is a ubiquitously distributed cytokine known to contribute to the pathogenesis of numerous pathological processes. The aim of this study was to measure serum concentrations of TGF- β 1 in severely ill COVID-19 patients and to analyze its relationship with selected hematological and biochemical parameters and with the disease outcome. The study population included 53 COVID-19 patients with severe clinical expression of the disease and 15 control subjects. TGF- β 1 was determined in serum samples and supernatants from PHA-stimulated whole blood cultures using ELISA assay. Biochemical and hematological parameters were analyzed using standard accepted methods. Our results showed that serum levels of TGF- β 1 in COVID-19 patients and controls correlate with the platelet counts. Also, positive correlations of TGF- β 1 with white blood cell and lymphocyte counts, platelet-to-lymphocyte (PLR) ratio, and fibrinogen level were shown, while negative correlations of this cytokine with platelet distribution width (PDW), D-dimer and activated partial thromboplastin time ( a -PTT) values in COVID-19 patients were observed. The lower serum values of TGF- β 1 were associated with the unfavorable outcome of COVID-19. In conclusion, TGF- β 1 levels were strongly associated with platelet counts and unfavorable disease outcome of severely ill COVID-19 patients.