Identification of novel regulatory pathways across normal human bronchial epithelial cell lines (NHBEs) and peripheral blood mononuclear cell lines (PBMCs) in COVID-19 patients using transcriptome analysis.

The SARS-CoV-2 is one of the most infectious and deadly coronaviruses, which has gripped the world, causing the COVID-19 pandemic. Despite the numerous studies being conducted on this virus, many uncertainties are with the disease. This is exacerbated by the speedy mutations acquired by the viral strain, which enables the disease to present itself differently in different people, introducing new factors of uncertainty. This study aims at the identification of regulatory pathways across two cell lines, namely, the peripheral blood mononuclear cell line (PBMC) and the normal human bronchial epithelial (NHBE) cell line. Both the above-mentioned cell lines were considered because they support viral replication. Furthermore, the NHBE cell line captures vital changes in the lungs, which are the main organs affected by the COVID-19 patients, and the PBMC cell line is closely linked to the body's immune system. RNA-Seq analysis, differential gene expression and gene set enrichment analysis for pathway identification were followed. Pathway analysis throws light upon the various systems affected in the body due to the COVID-19. Gene regulatory networks associated with the significant pathways were also designed. These networks aid in identifying various gene targets, along with their interactions. Studying the functionality of the pathways and the gene interactions associated with them, aided by long COVID studies, will provide immense clarity about the current COVID-19 scenario. In the long term, this will help in the design of therapeutic approaches against the SARS-CoV-2 and can also contribute to drug repurposing studies. Ultimately, this study identifies and analyses the relationship of various undiscovered or lesser explored pathways in the human body to the SARS-CoV-2 and establish a clearer picture of the association to help streamline further studies and approaches.