Olfactory Biopsies

Duke University

Status: Enrolling

Conditions: Alzheimer Disease; Smell Dysfunction; Smell Loss

Treatments: Other: Odor stimulation; Procedure: Olfactory biopsy; Diagnostic Test: olfactory testing

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT07021040

Pro00116591

1R01DC021422-01A1 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

This research study aims to investigate the function of the olfactory lining in the nasal cavity and its potential alterations in both healthy and diseased conditions. The olfactory lining is involved in the sense of smell.

The purpose of this study is to collect tissue from the nasal cavity.

Full description

The purpose of this study is to analyze cell populations active in human olfactory tissue in health and disease. This is a prospective study. Healthy participants or participants with known disease processes that may impact olfaction, such as Alzheimer's, inflammatory conditions, aging, or post-viral smell loss, will be included. Olfaction will be measured using standard psychophysical testing. Biopsies of the olfactory lining in the nasal cavity may be obtained in the otolaryngology clinic or the operating room, if the patient is having an unrelated endoscopic nasal surgery, and may be obtained using a punch technique or a cytology brush. Before biopsies, some patients may be asked to sniff an odor substance (such as lavender, mint, citrus, or cloves) briefly, to stimulate olfactory cells. Biopsies will be processed for assays in the PI's lab, including histology, primary culture assays, flow cytometry assays, or transcriptomic profiling.

Enrollment: 125 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Group 1: Alzheimer's study

Inclusion Criteria:

• Between the ages of 18 and 80
• Pre-clinical AD (this cohort consists of subjects who have normal cognitive testing and function, but have positive AD biomarkers);
• Symptomatic AD (a confirmed diagnosis of Alzheimer's or dementia who are capable of understanding and signing the consent document)

Exclusion Criteria:

• Advanced Alzheimer's/dementia
• Self-reported or known allergy to Afrin or Tetracain HCL (or related class of drugs)
• Active Rhinosinusitis symptoms
• Other known sinonasal disease history that would preclude biopsy (i.e prior sinus or skull base surgery directly impacting this anatomic region, sinonasal neoplasm in this anatomic region, olfactory cleft polyps)
• Parkinson's disease
• Unable or willing to complete the nasal endoscopy procedure.
• Unable to read or speak English
• Unable to provide legally effective consent

Group 2: Act-seq study or Non-AD controls

Inclusion Criteria:

• Age 18 years or older
• Patients being seen for rhinology or olfactory disorders
• Patients having unrelated endoscopic nasal surgery

Exclusion Criteria:

• Self-reported or known allergy to Afrin or Tetracain HCL (or related class of drugs)
• Unable or willing to complete the nasal endoscopy procedure
• Unable to read or speak English
• Unable to provide legally effective consent

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Parallel Assignment

Masking: None (Open label)

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125 participants in 2 patient groups

Alzheimer's study

Other group

Description:

Olfactory function will be assessed using the Smell Identification Test (SIT, Sensonics, Inc) or Sniffin' Sticks Test. Using topical intranasal decongestion/anesthetic (oxymetazoline/lidocaine), a cytology brush biopsy will be obtained from the olfactory cleft region of the nose in clinic exam room using a nasal endoscope.

Treatment:

Diagnostic Test: olfactory testing

Procedure: Olfactory biopsy

Other: Odor stimulation

Act-seq study or Non-AD controls

Other group

Description:

Olfactory function will be measured using established psychophysical testing via the Smell Identification Test or Sniffin' Sticks. Researchers will obtain biopsies from (1) normosmic subjects with or without odor stimulation, and (2) hyposmic subjects with history of upper respiratory infection (URI) as likely cause of the smell loss (such as COVID19) with or without odor stimulation.

Treatment:

Diagnostic Test: olfactory testing

Procedure: Olfactory biopsy

Other: Odor stimulation