Interferon Lambda Gene Expression in Iraqi COVID-19 Patients

Purpose: type III interferons (IFNλ) are an early line of defense in upper respiratory tract infections, such as severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). They have a crucial role in the control of the innate immune system and the modulation of immunological responses during the course of acute viral infection and tissue inflammation. The present study was aimed at evaluating the expression of IFNλ genes in Iraqi coronavirus disease (COVID-19)-infected patients. Materials and methods: ninety patients presented with COVID-19 and 50 healthy controls were recruited. Blood samples were obtained from the participants. Haematological and biochemical analyses were performed on the blood samples. IFNλ gene expression was assessed in peripheral blood mononuclear cells (PBMCs) of all the participants by real-time polymerase chain reaction (RT-PCR). Results: all COVID-19 patients had elevated relative expression of IFNλ-I, IFNλ-II, and IFNλ-III genes compared to controls, by 1.85 ± 0.25-, 39.9 ± 15.07-, and 4.001 ± 1.23-fold, respectively. According to the severity of the disease (moderate, severe, and critical), the relative expression of each IFN type was likewise elevated. However, the rise did not reach a significant level. On the other hand, there was a significant difference (p < 0.05) in the mean of relative expression between IFN-I, IFN-II, and IFN-III in total and each category of severity. Conclusion: the findings show that IFNλ gene expression was up-regulated in COVID-19 disease and neither age, sex, nor underlying diseases impacted the variations in expressions.