This observational study aims to better understand how the lining of the nose and sinuses differs across different sinonasal sites in humans, including participants with and without sinonasal inflammatory disease. Mucosal tissue samples will be collected from participants who are undergoing clinically indicated sinonasal surgery. The study will compare tissue structure, gene expression, protein expression, and immune cell composition among different regions of the sinonasal mucosa.

By studying these differences, researchers hope to identify site-specific features of human sinonasal mucosa and improve understanding of normal and disease-related changes in the nose and sinuses. This study does not assign participants to any treatment or intervention. The findings may provide a foundation for future research on chronic rhinosinusitis, nasal polyps, and other sinonasal diseases.

The human sinonasal mucosa lines different regions of the nasal cavity and paranasal sinuses and plays an important role in mucosal defense, inflammation, and tissue homeostasis. However, the biological characteristics of mucosa from different sinonasal sites are not fully understood.

This observational study will collect sinonasal mucosal tissue samples from participants undergoing clinically indicated sinonasal surgery. Samples may be obtained from different anatomical sites of the sinonasal tract when available as part of the surgical procedure. No treatment or intervention will be assigned by the study.

Collected samples will be analyzed to compare site-specific features of human sinonasal mucosa, including tissue structure, gene expression patterns, protein expression profiles, and immune cell composition. Relevant clinical information may also be collected to support interpretation of the biological findings.

The purpose of this study is to characterize the heterogeneity of human sinonasal mucosa across different anatomical sites. The results may help improve understanding of normal sinonasal mucosal biology and provide a reference for future studies of chronic rhinosinusitis, nasal polyps, and other sinonasal inflammatory diseases.

Inclusion Criteria:

• Adults aged 18 years or older.
• Scheduled for clinically indicated sinonasal surgery.
• Sinonasal mucosal tissue can be collected during surgery without significant additional risk.
• Able and willing to provide written informed consent.
• Relevant clinical information is available.

Exclusion Criteria:

• Unable or unwilling to provide informed consent.
• Younger than 18 years of age.
• Tissue collection may interfere with standard care or increase surgical risk.
• History of sinonasal malignancy, sinonasal radiotherapy, or chemotherapy affecting sinonasal mucosa.
• Active systemic infection or severe systemic disease affecting study participation or interpretation.
• Use of systemic corticosteroids, immunosuppressants, or biologics within 4 weeks before surgery.
• Insufficient or poor-quality tissue for planned analyses.

The study population will include adult participants undergoing clinically indicated sinonasal surgery. Sinonasal mucosal tissue samples may be collected from different anatomical sites of the nasal cavity and paranasal sinuses when available during the planned surgical procedure. Participants may include individuals with sinonasal inflammatory disease as well as individuals undergoing surgery for non-inflammatory sinonasal conditions, depending on clinical availability and protocol requirements. No study-specific treatment or intervention will be assigned.