Evaluation of the relationship between serum interleukin-1β levels and expression of inflammasome-related genes in patients with COVID-19.

Background: Inflammasomes are a group of molecules that are strongly involved in causing inflammation. This study aimed to evaluate the expression of NLR family pyrin domain containing 1 (NLRP1), NLRP3, and Apoptosis-associated speck-like protein containing a CARD (ASC) as well as their association with serum level of interleukin (IL)-1β in patients with coronavirus disease 2019 (COVID-19).

Methods: Thirty COVID-19 patients and 30 healthy subjects (HS) were recruited. Peripheral blood specimens were collected from subjects to assess NLRP1, NLRP3, and ASC gene expression by Real time-PCR technique. Serum levels of IL-1β were also measured via the enzyme-linked immunosorbent assay (ELISA).

Results: The findings showed no significant differences in serum IL-1β level between COVID-19 patients and the HS group. mRNA expression of ASC (P = 0.008) and NLRP1 (P = 0.03) gene had a significant increase in COVID-19 patients compared to HS, while there was no significant increase in the expression of NLRP3 between the studied group. There were significant correlations between patient's data and expression levels of NLRP1, NLRP3, IL-1β, and ACS.

Conclusions: NLRP1 and ASC may have a more critical role in the generation of the active form of IL-1β in COVID-19 patients compared to NLRP3. However, serum levels of IL-1β in patients did not show a significant increase, which may be due to the patient's condition and the application of virus escape mechanisms through impaired NLRP3 expression and its malfunction.