LncRNAs expression profile in a family household cluster of COVID-19 patients.

More than 3 years after the start of SARS-CoV-2 pandemic, the molecular mechanisms behind the viral pathogenesis are still not completely understood. Long non-coding RNAs (lncRNAs), well-known players in viral infections, can represent prime candidates for patients' risk stratification. The purpose of the current study was to investigate the lncRNA profile in a family cluster of COVID-19 cases with different disease progression, during the initial wave of the pandemic and to evaluate their potential as biomarkers for COVID-19 evolution. LncRNA expression was investigated in nasopharyngeal swabs routinely collected for diagnosis. Distinct expression patterns of five lncRNAs (HOTAIR, HOTAIRM1, TMEVPG1, NDM29 and snaR) were identified in all the investigated cases, and they were associated with disease severity. Additionally, a significant increase in the expression of GAS5-family and ZFAS1 lncRNAs, which target factors involved in the inflammatory response, was observed in the sample collected from the patient with the most severe disease progression. An lncRNA prognostic signature was defined, opening up novel research avenues in understanding the interactions between lncRNAs and SARS-CoV-2.