Mary O'Riordan, Ph.D.

Frederick C. Neidhardt Collegiate Professor
Professor of Microbiology and Immunology
Associate Dean of Graduate & Postdoctoral Studies
Accepting Students


Mary O’Riordan, Ph.D., is an associate professor of Microbiology and Immunology. She was also appointed associate dean for graduate and postdoctoral studies in June 2015.

She received her undergraduate degree in biology from the University of Washington, Seattle, M.A. in molecular biology from Princeton University and her doctorate in immunology from the University of California, San Francisco. After completing a postdoctoral fellowship at the University of California, Berkeley, she joined the faculty at the University of Michigan as an assistant professor of microbiology and immunology in 2003 and was promoted to associate professor in 2010.

Throughout her years on the faculty, Dr. O’Riordan has been active in the educational mission of the Medical School. In addition to teaching and mentoring, she has been a director for a number of graduate-level courses. She has been the thesis advisor for five graduate students and served on many dissertation committees. In 2013, she was inducted into the Medical School’s League of Educational Excellence and she also received the Endowment for Biological Sciences Teaching Award.

Research Interests

Our laboratory explores the interaction of intracellular bacterial pathogens with their host cells. We study the Gram-positive bacteria Listeria monocytogenes, methicillin-resistant Staphylococcus aureus and other bacterial pathogens as tools with which to explore host mechanisms that regulate infection and innate immune signaling. More recently, our research has focused on how host cell stress responses amplify innate immune signaling to enhance immunity to bacterial infection.

Research Opportunities for Rotating Students


D. Bronner, B. Abuaita, X. Chen, K. Fitzgerald, G. Nuñez, Y. He, X.M. Yin, M. O'Riordan. Endoplasmic Reticulum Stress Activates the Inflammasome via NLRP3- and Caspase-2-Driven Mitochondrial Damage. Immunity. 2015 Sep 15;43(3):451-62.

B. Abuaita, K. Burkholder, B. Boles, M. O'Riordan. The Endoplasmic Reticulum Stress Sensor Inositol-Requiring Enzyme 1α Augments Bacterial Killing through Sustained Oxidant Production. MBio. 2015 Jul 14;6(4):e00705.

D. Bronner, M. O'Riordan. A near death experience: Shigella manipulates host death machinery to silence innate immunity. EMBO J. 2014 Oct 1;33(19):2137-9.

M.E. Charbonneau, M. Gonzalez-Hernandez, H. Showalter, N. Donato , C. Wobus, M. O'Riordan. Small molecule deubiquitinase inhibitors promote macrophage anti-infective capacity. PLoS One. 2014 Aug 5;9(8):e104096.

D. Bronner, M. O'Riordan, Y. He. Caspase-2 mediates a Brucella abortus RB51-induced hybrid cell death having features of apoptosis and pyroptosis. Front Cell Infect Microbiol. 2013 Nov 27;3:83.

B. Abuaita, M. O'Riordan. Listeria exploits damage and death to spread bad news. Trends Microbiol. 2014 Jul;22(7):370-1.

S. Cassidy, J. Hagar, T. Kanneganti, L. Franchi, G. Nuñez, M. O'Riordan. Membrane damage during Listeria monocytogenes infection triggers a caspase-7 dependent cytoprotective response. PLoS Pathog. 2012;8(7):e1002628.

K. Burkholder, J. Perry, N. Donato, C. Wobus and M. O'Riordan. A small molecule deubiquitinase inhibitor increases localization of iNOS to the macrophage phagosome and enhances bacterial killing. Infection & Immunity. 2011 Dec;79(12):4850-7.

A. Radtke, K. Anderson, M. Davis, J. Swanson, M. DiMagno and M. O'Riordan. Listeria monocytogenes exploits CFTR-mediated chloride transport to escape the phagosome. Proc Natl Acad Sci U S A. 2011 Jan 10.

M. O'Riordan, L. Bauler, F. Scott and C. Duckett. 2008. Inhibitor of Apoptosis (IAP) Proteins in eukaryotic evolution and development: a model of thematic conservation. Developmental Cell. Oct;15(4):497-508.

L. Delbridge Bauler, C. Duckett and M. O'Riordan. 2008. XIAP regulates cytosolic-specific innate immunity to Listeria infection. PLoS Pathogens. Aug 29;4(8):e1000142.

A. Radtke, L. Delbridge S. Balachandran, G. Barber and M. O'Riordan. 2007. TBK1 protects vacuolar integrity during intracellular bacterial infection. PLoS Pathogens. Mar 2;3(3):e29.