Taste Bud-Derived Stem Cells in Humans

OBJECTIVES AND SPECIFIC AIMS:

The objectives of this proof-of-concept study are: (1) to investigate whether stem cells, normally present in tongue epithelium at the base of taste buds, can be propagated in the lab; if it is, then we wish (2) to investigate whether the stem cells can be differentiated into glucose-responsive insulin-secreting cells; (3) to investigate if the number of lingual-derived stem cells and their propagation rate are affected by age; (4) to investigate if the differentiation capability of the stem cells changes as a factor of aging.

EXPERIMENTAL DESIGN AND METHODS:

Ninety participants, thirty in each age group: ages 18-39 years, 40-59 years and 60 years old or older will be recruited for this pilot study. Of the thirty participants in each age group, fifteen will be men and fifteen will be women. Each eligible participant will have up to 5 fungiform papillae biopsied on the anterior part of the tongue during Visit 1.

MEDICAL RELEVANCE AND EXPECTED OUTCOME:

The development of this technique and its standardization to harvest these stem cells in humans is important for future therapeutic interventions, and may be an invaluable method for assessing novel cell based regenerative treatments for diabetes.

• INCLUSION CRITERIA:
• Age 18 years and older
• Healthy (see exclusion criteria below)
• Are able to understand the study risks and procedures, and consent to participate in the study.
• Are able to read and speak English.

Exclusion criteria

• Have less than 40 fungiform papillae on the anterior third portion of the tongue as evidenced by tongue photo taken during the screen visit.
• Does not agree to the use of their tissue samples to produce stem cells.
• A medical condition that requires the use of chronic anticoagulant medication use such as warfarin, clopidogrel, heparin or antiplatelet agents other than low dose aspirin (81mg).
• History of increased bleeding due to either a known medical condition or an undiagnosed cause.
• Active infections or chronic conditions that would prevent access to the biopsy area.
• Taking non-steroidal anti-inflammatory agents (NSAIDs) such as Motrin (Ibuprofen), Advil (Ibuprofen) or Naprosyn (Naproxen) and the participant is unable to stop taking them 4 days before and 3 days after the final biopsy procedure.
• Taking more than 81 mg of aspirin a day and the participant is unable to stop taking it for 4 days before and 3 days after the biopsy procedure.
• Allergic to Lidocaine (Xylocaine) or any other local anesthetic or the participant has had in the past a severe allergic reaction to similar drugs.
• Have taken steroids, other than ocular within 30 days of their scheduled biopsy procedure.
• HIV virus infection.
• Hepatitis B or C.
• Kidney disease (Creatinine greater than1.5 mg/dl or calculated creatinine clearance less than 50 cc/min).
• Liver disease (ALT, AST or alkaline phosphatase twice the normal serum concentration).
• Severe gastrointestinal diseases such as Crohn s disease or ulcerative colitis requiring continuous treatment.
• History of severe pulmonary disease such as chronic obstructive pulmonary disease (COPD) or asthma requiring continuous medication use.
• History of using any tobacco products within the past six months.
• History of severe psychiatric conditions associated with behavioral problems or requiring chronic medical treatment.
• Currently pregnant or breastfeeding.
• Current illness that as judged by the study physician substantially increases the risks associated with the tongue biopsy (active infections, allergies, etc.).