Tom Hannan, DVM, PhD

Instructor, Pathology & Immunology


  • BS, Georgetown University
  • DVM, Tufts Cummings School of Veterinary Medicine
  • PhD, Molecular Microbiology and Microbial Pathogenesis, Washington University in St. Louis

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Research Interests

I am a trained veterinarian and biomedical scientist with a passionate curiosity for and interest in understanding host responses to bacterial pathogens at the mucosa. After graduating from Tufts Veterinary School and working 8 years as a bovine veterinarian, I came to Washington University to pursue doctoral studies in Molecular Microbiology with Dr. Scott Hultgren, a pioneer in the field of Microbial Pathogenesis.

For my post-doctoral training, I began working under the combined mentorship of Dr. Hultgren and Dr. Marco Colonna, a world-renowned cellular immunologist, to understand the mucosal immunity of the bladder, first with the support of a K08 Mentored Clinical Scientist Research Career Development Award and then as a co-investigator on a Mucosal Immunology Study Team (MIST) U01. In 2013, I was awarded an NIH MIST Young Investigator Award (

My current research focuses on understanding the cellular and molecular mechanisms by which a prior urinary tract infection alters the mucosal immune response of the urinary bladder. Since 2016, I have also been employed by Fimbrion Therapeutics, Inc., a small biotechnology startup that is developing novel antimicrobial therapeutics that either target bacterial virulence or can potentiate the efficacy of existing first-line therapies. I am currently the Chief Scientific Officer at Fimbrion where I oversee the preclinical research program.


Lu Y, O’Brien VP, Livny J, Dorsey D, Bandyopadhyay N, Colonna M, Caparon MG, Roberson EDO, Hultgren SJ, Hannan TJ. Mucosal infection rewires TNFα signaling dynamics to skew susceptibility to recurrence. eLife 2019;8:e46677
O’Brien VP, Dorsey DA, Hannan TJ, Hultgren SJ. Host restriction of Escherichia coli recurrent urinary tract infection occurs in a bacterial strain-specific manner. PLoS Pathog. 2018: 14(12): e1007457.
O’Brien VP, Hannan TJ, Yu L, Livny J, Roberson ED, Schwartz DJ, Souza S, Mendelsohn CL, Colonna M, Lewis AL, Hultgren SJ. A mucosal imprint left by prior Escherichia coli bladder infection sensitizes to recurrent disease. Nat Microbiol. 2016: 2:16196.
Goneau LW, Hannan TJ, MacPhee RA, Schwartz DJ, Macklaim JM, Gloor GB, Razvi H, Reid G, Hultgren SJ, Burton JP. Subinhibitory antibiotic therapy alters recurrent urinary tract infection pathogenesis through modulation of bacterial virulence and host immunity. MBio. 2015; 6(2):e00356-15.
Nagamatsu K, Hannan TJ, Guest RL, Kostakioti M, Hadjifrangiskou M, Binkley J, Dodson K, Raivio TL, Hultgren SJ. Dysregulation of Escherichia coli α-hemolysin expression alters the course of acute and persistent urinary tract infection. Proc Natl Acad Sci U S A 2015: 112:E871-80.
Hannan TJ, Roberts PL, Riehl TE, van der Post S, Binkley JM, Schwartz DJ, Miyoshi H, Mack M, Schwendener RA, Hooton TM, Stappenbeck TS, Hansson GC, Stenson WF, Colonna M, Stapleton AE, Hultgren SJ. Inhibition of cyclooxygenase-2 prevents chronic and recurrent cystitis. EBioMedicine 2014: 1(1):46-57
Totsika M*, Kostakioti M*, Hannan TJ*, Upton M, Beatson SA, Janetka JW, Hultgren SJ, Schembri MA. A FimH inhibitor prevents acute bladder infection and treats chronic cystitis caused by multidrug resistant uropathogenic Escherichia coli ST131. J Infect Dis 2013: 208(6):921-8. *Contributed equally to the work.
Hannan TJ, Totsika M, Mansfield KJ, Moore KH, Schembri MA, Hultgren SJ. Host-pathogen checkpoints and population bottlenecks in persistent and intracellular uropathogenic Escherichia coli bladder infection. FEMS Microbiol Rev 2012: 36(3):616-48.
Hannan TJ, Mysorekar IU, Hung CS, Isaacson-Schmid M, Hultgren SJ. Early severe inflammatory responses to uropathogenic E. coli predispose to chronic and recurrent urinary tract infection. PLoS Pathogens 2010 August: 6(8) e1001042.
Hannan TJ, Mysorekar IU, Chen SL, Walker JN, Jones JM, Pinkner JS, Hultgren SJ, Seed PC. LeuX tRNA-dependent and -independent mechanisms of Escherichia coli pathogenesis in acute cystitis. Mol Microbiol 2008: 67: 116-128.