Single-cell RNA sequencing of nasal mucosa for molecular and genetic analysis of chemosensory dysfunction in post-COVID patients

Chemosensory especially olfactory dysfunction (OD) is common after COVID-19.The exact mechanism of this impairment is connected with molecular changes, which can be examined using single-cell RNA sequencing (SCS).The objective of this study was to evaluate cell populations,receptor expressions and analyze differential gene expressions leading to the identification of signaling pathways,in post-COVID patients (PCPs).

Single-cell RNA sequencing (Singelron,Germany) was conducted on nasal biopsy samples (n=26) obtained from clinically well-characterized patients,including 8 individuals without olfactory dysfunction and 18 individuals with olfactory dysfunction.

Within the analyzed specimens,a total of 46,550 cells were identified,yielding 18 distinct cell populations that encompassed all major epithelial cell types present in the conducting airways,including basal,secretory,and ciliated cells.Notably,these cells exhibited a predominance and proportional prevalence in post-COVID patients with olfactory dysfunction (OD) compared to those without OD.Increased expression of genes NQO1, RPL37,CEBPD,and UGT2A1 was demonstrated in all cell clusters of PCPs with OD.The intercellular communication can provide evidence of immune and epithelial cell signaling.CD46,FN1,and CDH1 receptors have a predominant information flow among communication receptors in PCPs with OD.

Immune cells have a crucial effect on the OD in PCPs.The understanding of cross-talk between immune and epithelial cells can lead to molecular and genetic underpinnings of COVID-related OD and will greatly advance diagnostics and treatment.

The authors declare that there is no conflict of interest