Xavier, Ramnik

Phone: 617-643-3331


Ramnik Xavier is the Kurt Isselbacher Professor of Medicine at Harvard Medical School and the Chief of Gastroenterology at the Massachusetts General Hospital. He is Board Certified in Medicine and Gastroenterology. Ramnik is also the Director of the Center for the Study of Inflammatory Bowel Disease (CSIBD) and a Senior Associate Member of the Broad Institute of MIT and Harvard. Ramnik is clinically active, teaching medical students, residents in medicine, and gastroenterology fellows rotating through the MGH.

Following his clinical training, he completed a postdoctoral fellowship with Professor Brian Seed in the Department of Molecular Biology at MGH and the Department of Genetics at the Harvard Medical School. The overall goal in the laboratory is to discover and understand the function of important mediators and effectors involved in innate (autophagy, pathogen-containing vacuole) and adaptive (T cell activation) immunity. Of particular interest are the cellular components and regulatory networks, which interact dynamically within temporal, spatial and pathophysiological contexts of innate and adaptive immunity. The lab is pursuing integrative systems approaches that closely couple genome-wide experimentation with high-throughput assays and computational methods.

A second area of focus is to examine the pathway defects associated with genetic variants in IBD/T1D and identify novel small molecules that interrupt signal transduction pathways associated with disease risk.

Selected Publications (from total of 231)


Aldrich LN, Kuo SY, Castoreno AB, Goel G, Kuballa P, Rees MG, Seashore-Ludlow BA, Cheah JH, Latorre IJ, Schreiber SL, Shamji AF, Xavier RJ
Discovery of a Small-Molecule Probe for V-ATPase Function.
J Am Chem Soc. 2015;:ePub - PMID: 25860544
Haberman Y, Tickle TL, Dexheimer PJ, Kim MO, Tang D, Karns R, Baldassano RN, Noe JD, Rosh J, Markowitz J, Heyman MB, Griffiths AM, Crandall WV, Mack DR, Baker SS, Huttenhower C, Keljo DJ, Hyams JS, Kugathasan S, Walters TD, Aronow B, Xavier RJ, Gevers D, Denson LA
Pediatric Crohn disease patients exhibit specific ileal transcriptome and microbiome signature.
J Clin Invest. 2015;125(3):1363 - PMID: 25729854
Sarmento OF, Svingen PA, Xiong Y, Xavier RJ, McGovern D, Smyrk TC, Papadakis KA, Urrutia RA, Faubion WA
A novel role for KLF14 in T regulatory cell differentiation.
Cell Mol Gastroenterol Hepatol. 2015;1(2):188-202.e4 - PMID: 25750932 - PMCID: PMC4349492
Kostic AD, Gevers D, Siljander H, Vatanen T, Hyötyläinen T, Hämäläinen AM, Peet A, Tillmann V, Pöhö P, Mattila I, Lähdesmäki H, Franzosa EA, Vaarala O, de Goffau M, Harmsen H, Ilonen J, Virtanen SM, Clish CB, Oreši? M, Huttenhower C, Knip M, , Xavier RJ
The Dynamics of the Human Infant Gut Microbiome in Development and in Progression toward Type 1 Diabetes.
Cell Host Microbe. 2015;17(2):260-273 - PMID: 25662751
Norman JM, Handley SA, Baldridge MT, Droit L, Liu CY, Keller BC, Kambal A, Monaco CL, Zhao G, Fleshner P, Stappenbeck TS, McGovern DP, Keshavarzian A, Mutlu EA, Sauk J, Gevers D, Xavier RJ, Wang D, Parkes M, Virgin HW
Disease-Specific Alterations in the Enteric Virome in Inflammatory Bowel Disease.
Cell. 2015;160(3):447-60 - PMID: 25619688 - PMCID: PMC4312520
Palsson-McDermott EM, Curtis AM, Goel G, Lauterbach MA, Sheedy FJ, Gleeson LE, van den Bosch MW, Quinn SR, Domingo-Fernandez R, Johnson DG, Jiang J, Israelsen WJ, Keane J, Thomas C, Clish C, Vanden Heiden M, Xavier RJ, O'Neill LA
Pyruvate Kinase M2 Regulates Hif-1? Activity and IL-1? Induction and Is a Critical Determinant of the Warburg Effect in LPS-Activated Macrophages.
Cell Metab. 2015;21(1):65-80 - PMID: 25565206
Guo AY, Stevens BW, Wilson RG, Russell CN, Cohen MA, Sturgeon HC, Thornton A, Giallourakis C, Khalili H, Nguyen DD, Sauk J, Yajnik V, Xavier RJ, Ananthakrishnan AN
Early life environment and natural history of inflammatory bowel diseases.
BMC Gastroenterol. 2014;14(1):216 - PMID: 25510175 - PMCID: PMC4300207
Knights D, Silverberg MS, Weersma RK, Gevers D, Dijkstra G, Huang H, Tyler AD, van Sommeren S, Imhann F, Stempak JM, Huang H, Vangay P, Al-Ghalith GA, Russell C, Sauk J, Knight J, Daly MJ, Huttenhower C, Xavier RJ
Complex host genetics influence the microbiome in inflammatory bowel disease.
Genome Med. 2014;6(12):107 - PMID: 25587358 - PMCID: PMC4292994
Paulus GL, Xavier RJ
Autophagy and checkpoints for intracellular pathogen defense.
Curr Opin Gastroenterol. 2014;31(1):14-23 - PMID: 25394238 - PMCID: PMC4330559
Buffen K, Oosting M, Quintin J, Ng A, Kleinnijenhuis J, Kumar V, van de Vosse E, Wijmenga C, van Crevel R, Oosterwijk E, Grotenhuis AJ, Vermeulen SH, Kiemeney LA, van de Veerdonk FL, Chamilos G, Xavier RJ, van der Meer JW, Netea MG, Joosten LA
Autophagy Controls BCG-Induced Trained Immunity and the Response to Intravesical BCG Therapy for Bladder Cancer.
PLoS Pathog. 2014;10(10):e1004485 - PMID: 25356988 - PMCID: PMC4214925
Kleinnijenhuis J, Quintin J, Preijers F, Joosten LA, Jacobs C, Xavier RJ, van der Meer JW, van Crevel R, Netea MG
BCG-induced trained immunity in NK cells: Role for non-specific protection to infection.
Clin Immunol. 2014;155(2):213-219 - PMID: 25451159
Kumar V, Wijmenga C, Xavier RJ
Genetics of immune-mediated disorders: from genome-wide association to molecular mechanism.
Curr Opin Immunol. 2014;31C:51-57 - PMID: 25458995
Liao J, Jijon HB, Kim IR, Goel G, Doan A, Sokol H, Bauer H, Herrmann BG, Lassen KG, Xavier RJ
An Image-Based Genetic Assay Identifies Genes in T1D Susceptibility Loci Controlling Cellular Antiviral Immunity in Mouse.
PLoS One. 2014;9(9):e108777 - PMID: 25268627 - PMCID: PMC4182575
Platt RJ, Chen S, Zhou Y, Yim MJ, Swiech L, Kempton HR, Dahlman JE, Parnas O, Eisenhaure TM, Jovanovic M, Graham DB, Jhunjhunwala S, Heidenreich M, Xavier RJ, Langer R, Anderson DG, Hacohen N, Regev A, Feng G, Sharp PA, Zhang F
CRISPR-Cas9 Knockin Mice for Genome Editing and Cancer Modeling.
Cell. 2014;159(2):440-55 - PMID: 25263330 - PMCID: PMC4265475
Draberova L, Bugajev V, Potuckova L, Halova I, Bambouskova M, Polakovicova I, Xavier RJ, Seed B, Draber P
Transmembrane adaptor protein PAG/CBP is involved in both positive and negative regulation of mast cell signaling.
Mol Cell Biol. 2014;34(23):4285-300 - PMID: 25246632 - PMCID: PMC4248753