Personal Statement

The focus of my research has been on: (1) characterizing the functional aspects of EspP in inducing macropinocytosis of Shiga toxin, and (2) determining the mechanisms by which the colon can regenerate post- injury. From my postdoctoral work in the laboratory of Dr. Olga Kovbasnjuk, I have been working to determine the pathophysiologic effects of enterohemorrhagic E. coli (EHEC) interaction with human enterocytes.

Using both an in vitro cell model and an in vivo murine model, I initially characterized an EHEC protein, the bacterial serine protease, EspP, as essential in the pathogenicity of this infection. Additionally, I received training in the laboratory of Dr. Hugo de Jonge at Erasmus University (Rotterdam, NL) to establish human, non-cancerous, ex vivo intestinal and colonic organoid cultures derived from adult stem cells.

Recently, I validated them as a functional model of normal human intestinal physiology and infectious pathophysiology. Preliminary data obtained from the EHEC studies and/or using enteroids have been instrumental in obtaining several grants in the past year (including a U18/UH3, U01, R24, and Gates Foundation grant; co-PIs: Donowitz, Kovbasnjuk, others), including a K01 (PI: In).

Based on my research expertise with molecular and imaging tools and our novel and exciting preliminary data gained on human colonic organoids, I have the unique technical skills and comprehensive background to be successful in these proposed studies. I have recently developed a technical protocol to use CRISPR/Cas9 gene editing to create stable knockout human organoid cultures.

Using this technique, I have started to interrogate the role of specific stem cell-related genes in colon regeneration and colorectal cancer initiation. Based on our novel and exciting preliminary data gained on the CRISPR-edited human organoids, I believe I am uniquely positioned to aid in achieving the goals proposed in this application.