Arginase 1 (Arg1) as an Up-Regulated Gene in COVID-19 Patients: A Promising Marker in COVID-19 Immunopathy

Background: The coronavirus disease 2019 (COVID-19) outbreak, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been declared a global pandemic. It is well-established that SARS-CoV-2 infection can lead to dysregulated immune responses. Arginase-1 (Arg1), which has a pivotal role in immune cells, can be expressed in most of the myeloid cells, e.g., neutrophils and macrophages. Arg1 has been associated with the suppression of antiviral immune responses. Methods: Whole blood was taken from 21 COVID-19 patients and 21 healthy individuals, and after RNA extraction and complementary DNA (cDNA) synthesis, gene expression of Arg1 was measured by real-time PCR. Results: The qPCR results showed that the expression of Arg1 was significantly increased in COVID-19 patients compared to healthy individuals (p < 0.01). The relative expression analysis demonstrated there were approximately 2.3 times increased Arg1 expression in the whole blood of COVID-19 patients. Furthermore, the receiver operating characteristic (ROC) analysis showed a considerable diagnostic value for Arg1 expression in COVID-19 (p = 0.0002 and AUC = 0.8401). Conclusion: Arg1 might be a promising marker in the pathogenesis of the disease, and it could be a valuable diagnostic tool.