Conchotomy involves the reduction or removal of hypertrophic nasal turbinates, aesthetic nose surgery is a surgical procedure that aims to enhance the appearance of the nose, while functional endoscopic sinus surgery is a minimally invasive procedure focused on treating sinus conditions by removing obstructions and improving sinus drainage.

Multiple techniques and functional assays will be used to fully investigate the functional differences between epithelial/basal cells isolated from healthy and CRSwNP samples. The differences in barrier composition will be assessed through TEER measurements (Ω × cm2) and FD4 permeability assays (ng/ml). Moreover, barrier composition is investigated by examining differences in membrane markers and junction expression through immunofluorescence and RT-qPCR. Finally, primary isolated cells will be used to assess protein levels through immunostainings, flow cytometry, and Western blots.

To characterize differences in gene expression, or identify specific genes/cell populations that can contribute to CRSwNP, scRNA-sequencing will be performed, as well as bulk RNA sequencing. Depending on these results, specific triggers or receptors that can contribute to CRSwNP will be investigated by stimulation experiments. Besides, the effect on epigenetic imprinting before and after stimulation by performing ATAC-sequencing or DNA methylation profiling will be studied as well.

The interaction between basal and regulatory T cells in relation to homeostasis and regeneration, and how this might change or contribute in/to CRSwNP will be investigated by co-culturing these cells. This will be assessed through the analysis of the supernatants using the Olink platform to investigate cytokines etc. Besides, there will be bulk RNA sequencing to look at changes in gene expression, as well as proliferation and growth assays to see the effect of T cells on basal cells and vice versa. To look at functional changes we can asses different functional assays and techniques (see outcome 1).