The Role of Bitter and Sweet Taste Receptors in Upper Airway Immunity

  • Alan D. Workman
  • James N. Palmer
  • Nithin D. Adappa
  • Noam A. Cohen
Rhinosinusitis (J Mullol, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Rhinosinusitis


Over the past several years, taste receptors have emerged as key players in the regulation of innate immune defenses in the mammalian respiratory tract. Several cell types in the airway, including ciliated epithelial cells, solitary chemosensory cells, and bronchial smooth muscle cells, all display chemoresponsive properties that utilize taste receptors. A variety of bitter products secreted by microbes are detected with resultant downstream inflammation, increased mucous clearance, antimicrobial peptide secretion, and direct bacterial killing. Genetic variation of bitter taste receptors also appears to play a role in the susceptibility to infection in respiratory disease states, including that of chronic rhinosinusitis. Ongoing taste receptor research may yield new therapeutics that harness innate immune defenses in the respiratory tract and may offer alternatives to antibiotic treatment. The present review discusses taste receptor-protective responses and analyzes the role these receptors play in mediating airway immune function.


T2R38 Bitter taste receptor Sweet taste receptor Solitary chemosensory cell Airway immune function Upper airway immunity 


Compliance with Ethical Standards

Conflict of Interest

Dr. Cohen has a patent “Therapy and Diagnostics for Respiratory Infection” 61/697,652 (filed 12/6/12) WO2013112865 pending. Drs. Workman, Palmer, and Adappa declare no conflicts of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Alan D. Workman
    • 1
    • 2
  • James N. Palmer
    • 1
    • 2
  • Nithin D. Adappa
    • 1
    • 2
  • Noam A. Cohen
    • 1
    • 2
    • 3
    • 4
  1. 1.Department of Otorhinolaryngology: Head and Neck SurgeryUniversity of Pennsylvania Medical CenterPhiladelphiaUSA
  2. 2.Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUSA
  3. 3.Monell Smell and Taste CenterPhiladelphiaUSA
  4. 4.Philadelphia Veterans Affairs Medical CenterPhiladelphiaUSA

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