Christina Ahn Hickey, M.D., M.A

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Instructor in Pediatrics, Gastroenterology, Hepatology and Nutrition
Gastroenterology, Hepatology and Nutrition

phone: (314) 454-6173

Research Interests

Defining host-microbial interactions that lead to development of inflammatory bowel disease My main research interest is in the microbial-host interaction in inflammatory bowel disease (IBD). Because of this interest, I am working in Thaddeus Stappenbeck’s lab on the mechanism of the colitogenic potential of commensal bacteria in a genetically predisposed IBD mouse model. My core hypothesis is that the colitogenic potential of a given Bacteroides sp. is directly related to its ability to evade and penetrate host defenses such as mucus and the epithelial layer. I recently found that one such commensal, Bacteroides thetaiotaomicron (B. theta) antigen accesses host immune cells in a sulfatase dependent manner. B. theta does so via a novel mechanism, outer membrane vesicles, which contain enzymatic properties. My current work is focused on the specific mechanisms of B. theta OMVs to traverse through the mucus and epithelial layer. I am using a combination of primary cell culture techniques, genomic screens, and genetic mouse models to pursue this question. Currently, I am supported with funding from the Pediatric Scientist Development Program to pursue a basic science project in my area of interest.


  • BS, Graduated with Distinction (top 15% of class), Stanford University2003
  • MD, Elisabeth L. Demonchaux Prize in Pediatrics, Washington University School of Medicine2009
  • MA, Washington University School of Medicine2009


  • Residency, Washington University2009 - 2012
  • Fellowship, Washington University2012 - 2015

Licensure and Board Certification

  • Pediatric Board Certified, 2013 - Pres
  • MO, State of Missouri Medical License, 2015 - Pres


  • National Merit Scholar1999
  • Stanford University Chemistry Summer Undergraduate Research Bing Fellowship2001 - 2001
  • Phi Beta Kappa2003
  • Olin Fellowship full tuition scholarship to Washington University School of Medicine2004 - 2009
  • First place in prose division of The Legible Script National Literary Competition for Medical Students2006
  • Essay selected for Princeton Review's "Medical School Essays that have Made a Difference"2007
  • Doris Duke Clinical Research Fellowship2007 - 2008
  • Distinguished Graduate in Medicine, highlighted in the Washington Record Graduation Issue2009
  • Elisabeth L. Demonchaux Prize in Pediatrics2009
  • Teaching and Tomorrow participant in NASPGHAN's October 2010 Conference2010
  • Pediatric Scientist Development Program grant recipient2012 - Pres

Selected Publications view all (10)

Publication Co-Authors

Pediatric Sloughing Esophagitis: A Case Report and Discussion. Fetal Pediatr Pathol. 2018;1-6. PMID:29781748 
Tropism for tuft cells determines immune promotion of norovirus pathogenesis. Science. 2018;360(6385):204-208. PMCID:PMC6039974  PMID:29650672 
A Dietary Fiber-Deprived Gut Microbiota Degrades the Colonic Mucus Barrier and Enhances Pathogen Susceptibility. Cell. 2016;167(5):1339-1353.e21. PMCID:PMC5131798  PMID:27863247 
Colitogenic Bacteroides thetaiotaomicron Antigens Access Host Immune Cells in a Sulfatase-Dependent Manner via Outer Membrane Vesicles. Cell Host Microbe. 2015;17(5):672-80. PMCID:PMC4432250  PMID:25974305 
Early volume expansion during diarrhea and relative nephroprotection during subsequent hemolytic uremic syndrome. Arch Pediatr Adolesc Med. 2011;165(10):884-9. PMCID:PMC4064458  PMID:21784993 
Deer sausage: a newly identified vehicle of transmission of Escherichia coli O157:H7. J Pediatr. 2009;155(4):587-9. PMID:19773004 
From diarrhoea to haemolytic uraemic syndrome - when to seek advice. J Med Microbiol. 2009;58(Pt 4):397-8. PMID:19273631 
Shiga-toxin producing Escherichia coli and the hemolytic uremic syndrome: what have we learned in the past 25 years? Adv Exp Med Biol. 2009;634:1-17. PMID:19280844 
Isolation of patients acutely infected with Escherichia coli O157:H7: low-tech, highly effective prevention of hemolytic uremic syndrome. Clin Infect Dis. 2008;46(8):1197-9. PMID:18444855 
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