SARS-COV-2 ORF9b Dysregulate Fibrinogen and Albumin Genes in a Liver Cell Line.

Background: Individuals experiencing severe cases of Coronavirus Disease 2019 (COVID-19) exhibited elevated fibrinogen levels and decreased albumin levels, potentially linked to the presence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) proteins. Consequently, our study endeavors to examine the impact of SARS-CoV-2 ORF9b on the expression of fibrinogen and albumin genes within the Hep-G2 cell line.

Methods: In this study, the Hep-G2 liver cell line was utilized alongside the plasmid pcDNA3.1 hyg+ containing ORF9b from the SARS-CoV-2 strain originating in Wuhan. Transfection procedures were executed, and the transfected cells were selected utilizing hygromycin B. Validation of ORF9b expression was conducted through SYBR green-based real-time PCR, and the expression of the Fibrinogen α (FGA), Fibrinogen β (FGB), Fibrinogen γ (FGG), and Albumin (ALB) genes was quantified using the same method.

Results: The real-time PCR analysis revealed a significant upregulation of fibrinogen genes-α (P=0.03), β (P=0.02), and γ (P=0.029) in Hep-G2 cells containing ORF9b compared to control cells. Furthermore, the findings indicated a markedly lower expression level of albumin in Hep-G2 cells harboring ORF9b compared to the control cells (P=0.028).

Conclusions: The findings suggest that SARS-CoV-2 ORF9b could potentially influence the course of SARS-CoV-2 infection by triggering the expression of α, β, and γ fibrinogen gene chains while suppressing the albumin gene. Further investigations are warranted to validate these observations across various SARS-CoV-2 strains exhibiting differing levels of pathogenicity.