Potential Role of Inflammasome NLRP3 And IL-1B Gene Expression In COVID-19 Patients: Impact of Ferretin and D -Dimer.

Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a viral infection that results in respiratory disease, which can evolve into multiorgan failure (MOF), leading to death (Aida A Abdelmaksoud et al., 2021).

The first cases of COVID-19 were detected in Wuhan, China, in 2019. Since then, the illness has spread rapidly around the country and the world reaching a pandemic level (Rocklöv J et al., 2020). Cases have been reported in more than 180 countries to the World Health Organization (WHO), including more than two million deaths (WHO, 2021).

Several biochemical alterations have been described in COVID-19 patients as lymphopenia, thrombocytopenia and increased levels of C-reactive protein. The hallmark of severe COVID-19 is the cytokine storm accompanied by a hyperinflammatory response in the host due to the release of large amounts of pro-inflammatory cytokines IL-1β, IL-6, IL-2, IL-7, TNF-α, interferon-γ (IFN)-γ, CRP, procalcitonin (PCT), lactate dehydrogenase (LDH), erythrocyte sedimentation rate (ESR) and ferritin (Marcello Ciaccio and Agnello, 2020; Shah A., 2020).

The inflammasome is a multiprotein complex, known for its role in the innate immune response against viral diseases and a regulator of processing of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18. Inflammasome contains a NOD-like receptor (NLR) sensor protein and pyrin domain-containing 3 , after which, NLRP3 Inflammasome was named (de Rivero Vaccari et al., 2020). The presence of inflammasome-derived products such as IL-1β, IL-18, and LDH in patients' sera suggests inflammasome engagement (Chen G et al., 2020).

Increased IL-6, IL-10, and IL-4 were found in patients when compared with controls, indicating that SARS-CoV-2 infects human monocytes and triggers NLRP3 inflammasome activation. However, the definitive demonstration of NRLP3 inflammasome participation is still required because these products can be produced via inflammasome-independent pathways (Rodrigues et al., 2021). But, the possible contribution of NLRP3 inflammasome activation and their ability to induce IL-1β production is still not clear .