Determination of both the expression and serum levels of epidermal growth factor (EGF) and transforming growth factor-β1 (TGFβ1) genes in SARS-CoV- 2 Running title: SARS coronavirus-2 and EGF- TGFβ1

Aim: We aimed to evaluate the effects of both the expression and serum levels of Epidermal growth factor ( EGF ) and Transforming growth factor-β1 ( TGF-β1 ) genes that can lead to fibrosis SARS-CoV-2, which has different degrees of cellular damage as mild, moderate, severe, and critical illness. Method: Totally 45 individuals (male:21(46.67%); female:24(53.33%)) with COVID-19 infection were included in this study. Four groups were constituted as mild (n=16)], moderate(n=10), severe(n=10), and critical(n=9) according to the severity of the disease. Blood samples were drawn from the patients, and hemograms, EGF and TGFβ1 gene expression, and serum levels were evaluated. Results: The mean age of individuals was 57.311±18.383 (min:28, max:94). Significant differences were found among the groups for PLT (χ ² =9.955; p=0.019), CRP (χ ² =7.693; p=0.053), Ferritin (χ ² =22.196; p<0.001), D-dimer (χ ² =21.982; p=0.000), LDH (χ ² =21.807; p<0.001) and all these parameters (exclude PLT in severe groups) was increased depending on the severity of the disease. Additionally, significant differences were detected for EGF (χ ² =29.528; p<0.001), TGFB1 (χ ² =28.981; p<0.001) expression (that increased depending on the disease severity), and EGF (χ ² =7.84; p=0.049), TGFB1 (χ ² =17.451; p=0.001) serum concentration levels (that decreased depending on the disease severity). Conclusion: This study found statistically significant differences for both EGF 2 ^-ΔΔCt . TGFβ1 2 ^-ΔΔCt and EGF, TGFβ1 serum concentration values among all patient groups. As disease severity increased, EGF 2 ^-ΔΔCt . TGFβ1 2 ^-ΔΔCt levels increased, while EGF and TGFβ1 serum concentration levels decreased . Perhaps this study will be useful in managing COVID-19 infection severity and pulmonary fibrosis cases secondary to COVID-19.