Marco Tizzano



Assistant Member, Monell Chemical Senses Center
Adjunct Assistant Professor, School of Dental Medicine, University of Pennsylvania


Ph.D., Congenital Metabolic Physiopathology, University of Verona, Italy

Research Summary

Chemical irritation of the airways and other mucosae is my main focus. I study solitary chemosensory cells (SCCs), a specialized chemosensitive nasal epithelial sentinel cell type innervated by the trigeminal nerve, which responds to bitter compounds, irritants, and bacterial metabolites. When activated, SCCs trigger protective reflexes and inflammatory/immune responses. At the behavioral level I’m interested in avoidance responses to inhaled irritants which activate the SCCs. There are classes of irritants that are connected to non-allergic and allergic inflammation and we are interested in determining how SCCs and the trigeminal system may interact with either of these. We are also investigating how irritants/allergens can affect the frequency of SCCs and how activation of SCCs can modify the mucosa microbiome. Moreover, we are studying the function of taste and olfactory receptors ectopically expressed in other organs and tissue in connection to pain and inflammation. We are also characterizing the function of non-lingual taste buds and their relation to salivary gland and taste perception. Finally, I’m particularly interested in long-range inflammation of the meninges as a consequence of nasal irritation and the mechanisms underlying neurovascular pathophysiology, such as headaches and migraines, which are triggered by exposure to airborne irritants, odorants, and bacterial molecules.


solitary chemosensory cells, extra-oral taste receptors, irritants, Pseudomonas aeruginosa, extra-nasal olfactory receptors, trigeminal, allergic and non-allergic inflammation, olfaction and taste, avoidance behavior, airway diseases, migraine, salivary system, pain.

Representative Publications

Xin Zheng*, Marco Tizzano*, Kevin Redding, Jinzhi He, Xian Peng, Peihua Jiang, Xin Xu, Xuedong Zhou, Robert F. Margolskee (*These authors contributed equally to this work). Gingival Solitary Chemosensory Cells Are Immune Sentinels for Periodontitis. Nat. Commun. 2019, 10:4496 |

Genovese F, Tizzano M. Microvillous cells in the olfactory epithelium express elements of the solitary chemosensory cell transduction signaling cascade. PLoS One. 2018 Sep 13;13(9):e0202754. doi: 10.1371/journal.pone.0202754.

Marco Tizzano, Laura Grigereit, Nicole Shultz, Matthew S. Clary and Thomas E. Finger. Immunohistochemical Analysis of Human Vallate Taste Buds. Chemical Senses, 2015, 40(9):655-60. doi:10.1093/chemse/bjv048

CJ Saunders MC, Thomas E Finger, Marco Tizzano. Cholingeric Neurotransmission Links Solitary Chemosensory Cells to Nasal Inflammation. Proc Natl Acad Sci U S A. 111(16):6075-80 (2014)(Cover).

Tizzano M, Cristofoletti M, Sbarbati A, Finger TE. Expression of taste receptors in solitary chemosensory cells of rodent airways. BMC Pulm Med. 11:3 (2011). PMCID: PMC3031280

Marco Tizzano, Brian Gulbransen, Aurelie Vandenbeuch, Tod Clapp, Jake Herman, Hiruy Sibhatu, Wayne Silver, Mair Churchill, Sue Kinnamon, Thomas Finger. Nasal Chemosensory Cells Utilize Bitter Taste Signalling to Detect Irritants and Bacterial Signals. Proc Natl Acad Sci USA, 107(7):3210-5 (2010). PMCID: PMC2840287

Tizzano M, Dvoryanchikov G, Barrows JK, Kim S, Chaudhari N, Finger TE. Expression of Galpha14 in sweet-transducing taste cells of the posterior tongue. BMC Neurosci. 9:110 (2008)(Cover). PMID:19014514

Marco Tizzano

Contact Information

(267) 519-4845