Scott A Boitano
Associate Research Scientist, Respiratory Sciences
Professor, BIO5 Institute
Professor, Cellular and Molecular Medicine
Professor, Physiological Sciences - GIDP
Professor, Physiology
Primary Department
Department Affiliations
(520) 626-2105
Research Interest
Dr. Scott Boitano Ph.D., is a Professor of Physiology, Cellular and Molecular Medicine, the BIO5 Institute and Associate Research Scientist of the Arizona Respiratory Center. Dr. Boitano received a B.S. in Plant Biology from University of California; Berkeley and a Ph.D. in Genetics & Cell Biology from Washington State University. Dr. Boitano’s primary research interest is in cell respiration. This encompasses the analysis and observation of cell physiology, cell-cell communications and cell-pathogen interactions. Dr. Boitano’s research pertains to the upper airway epithelium is an active cellular layer with ciliary movement to clear materials, the ability to secrete inflammatory effectors, and a biological barrier function that helps protect against pathogenic microorganisms, foreign insults and injury. Although much is known concerning the microbial genetics and microbial signaling of infection by Bordetella, relatively little is known about host cell pathology after exposure to Bordetella. Individuals have a primary tissue culture system that serves as an in vitro model of airway cell signaling and communication, and a battery of B. bronchiseptica strains, some of which are mutant in key factors shown to inhibit their ability to establish infection in animal models. His research goal is to define specific pathogen factors that alter host cell physiology to initiate or overcome host cell defense. The Boitano lab also analyzes the layers of the alveoli of the distal mammalian lung. Minimal information is known about this subject and Dr. Boitano believes that this model system for alveolar intercellular communication could expedite the formulating and testing of new medical treatments for dysfunctional alveolar cell physiology that underlies specific airway conditions following disease, insult and injury in the lung.

Publications

Boitano, S., Flynn, A. N., Sherwood, C. L., Schulz, S. M., Hoffman, J., Gruzinova, I., & Daines, M. O. (2011). Alternaria alternata serine proteases induce lung inflammation and airway epithelial cell activation via PAR2. American journal of physiology. Lung cellular and molecular physiology, 300(4), L605-14.

Allergens are diverse proteins from mammals, birds, arthropods, plants, and fungi. Allergens associated with asthma (asthmagens) share a common protease activity that may directly impact respiratory epithelial biology and lead to symptoms of asthma. Alternaria alternata is a strong asthmagen in semiarid regions. We examined the impact of proteases from A. alternata on lung inflammation in vivo and on cleaving protease-activated receptor-2 (PAR(2)) in vitro. A. alternata filtrate applied to the airway in nonsensitized Balb/c mice induced a protease-dependent lung inflammation. Moreover, A. alternata filtrate applied to human bronchial epithelial cells (16HBE14o-) induced changes in intracellular Ca(2+) concentration ([Ca(2+)](i)), consistent with PAR(2) activation. These effects were blocked by heat inactivation or by serine protease inhibition of A. alternata filtrates, and mimicked by PAR(2) specific ligands SLIGRL-NH(2) or 2-furoyl-LIGRLO-NH(2), but not the PAR(1)-specific ligand TFLLR-NH(2). Desensitization of PAR(2) in 16HBE14o- cells with 2-furoyl-LIGRLO-NH(2) or trypsin prevented A. alternata-induced [Ca(2+)](i) changes while desensitization of PAR(1), PAR(3), and PAR(4) with thrombin had no effect on A. alternata-induced Ca(2+) responses. Furthermore, the Ca(2+) response to A. alternata filtrates was dependent on PAR(2) expression in stably transfected HeLa cell models. These data demonstrate that A. alternata proteases act through PAR(2) to induce rapid increases in human airway epithelial [Ca(2+)](i) in vitro and cell recruitment in vivo. These responses are likely critical early steps in the development of allergic asthma.

Sherwood, C. L., Liguori, A. E., Olsen, C. E., Lantz, R. C., Burgess, J. L., & Boitano, S. (2013). Arsenic compromises conducting airway epithelial barrier properties in primary mouse and immortalized human cell cultures. PloS one, 8(12), e82970.
BIO5 Collaborators
Scott A Boitano, Clark Lantz

Arsenic is a lung toxicant that can lead to respiratory illness through inhalation and ingestion, although the most common exposure is through contaminated drinking water. Lung effects reported from arsenic exposure include lung cancer and obstructive lung disease, as well as reductions in lung function and immune response. As part of their role in innate immune function, airway epithelial cells provide a barrier that protects underlying tissue from inhaled particulates, pathogens, and toxicants frequently found in inspired air. We evaluated the effects of a five-day exposure to environmentally relevant levels of arsenic {

Sherwood, C. L., Daines, M. O., Price, T. J., Vagner, J., & Boitano, S. (2014). A highly potent agonist to protease-activated receptor-2 reveals apical activation of the airway epithelium resulting in Ca2+-regulated ion conductance. American journal of physiology. Cell physiology, 307(8), C718-26.

The airway epithelium provides a barrier that separates inhaled air and its various particulates from the underlying tissues. It provides key physiological functions in both sensing the environment and initiating appropriate innate immune defenses to protect the lung. Protease-activated receptor-2 (PAR2) is expressed both apically and basolaterally throughout the airway epithelium. One consequence of basolateral PAR2 activation is the rapid, Ca(2+)-dependent ion flux that favors secretion in the normally absorptive airway epithelium. However, roles for apically expressed PAR2 activation have not been demonstrated, in part due to the lack of specific, high-potency PAR2 ligands. In the present study, we used the newly developed PAR2 ligand 2at-LIGRLO(PEG3-Pam)-NH2 in combination with well-differentiated, primary cultured airway epithelial cells from wild-type and PAR2 (-/-) mice to examine the physiological role of PAR2 in the conducting airway after apical activation. Using digital imaging microscopy of intracellular Ca(2+) concentration changes, we verified ligand potency on PAR2 in primary cultured airway cells. Examination of airway epithelial tissue in an Ussing chamber showed that apical activation of PAR2 by 2at-LIGRLO(PEG3-Pam)-NH2 resulted in a transient decrease in transepithelial resistance that was due to increased apical ion efflux. We determined pharmacologically that this increase in ion conductance was through Ca(2+)-activated Cl(-) and large-conductance K(+) channels that were blocked with a Ca(2+)-activated Cl(-) channel inhibitor and clotrimazole, respectively. Stimulation of Cl(-) efflux via PAR2 activation at the airway epithelial surface can increase airway surface liquid that would aid in clearing the airway of noxious inhaled agents.

Isakson, B. E., Olsen, C. E., & Boitano, S. (2006). Laminin-332 alters connexin profile, dye coupling and intercellular Ca2+ waves in ciliated tracheal epithelial cells. Respiratory research, 7, 105.

Tracheal epithelial cells are anchored to a dynamic basement membrane that contains a variety of extracellular matrix proteins including collagens and laminins. During development, wound repair and disease of the airway epithelium, significant changes in extracellular matrix proteins may directly affect cell migration, differentiation and events mediated by intercellular communication. We hypothesized that alterations in cell matrix, specifically type I collagen and laminin alpha3beta3gamma2 (LM-332) proteins within the matrix, directly affect intercellular communication in ciliated rabbit tracheal epithelial cells (RTEC).

Lantz, R. C., Chau, B., & Boitano, S. A. (2016). Inhalation of arsenic-containing dusts during lung development alters pulmonary function in adult mice. Toxicological Sciences.
BIO5 Collaborators
Scott A Boitano, Clark Lantz