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Graduate School of Biomedical Sciences

Joan Mecsas

Professor of Molecular Biology & Microbiology
Joan Mecsas

Joan Mecsas

Professor of Molecular Biology & Microbiology

Office phone: 617-636-2742
Lab phone: 617-636-7613
Campus: Boston
Office: South Cove 803
South Cove 8
BA, Biochemistry, Swarthmore College
PhD, Cellular & Molecular Biology, University of Wisconsin, Madison
Postdoctoral Training, Stanford University
Research synopsis: 

Our overall interest is to understand the interactions between bacterial pathogens and mammalian hosts that dictate the outcome of infection. We study two Gram-negative bacterial pathogens, Yersinia pseudotuberculosis and Klebsiella pneumoniae, that cause infection in a variety of tissue sites. Yersinia pseudotuberculosis is a food-borne pathogen that colonizes the small intestine and breaches the intestinal epithelial barrier through a specialized cell, called an M cell, to reach intestinal lymph tissues. Within the lymph nodes, Y. pseudotuberculosis employs a type 3 secretion system to inject effector proteins, Yops, into neutrophils. We have developed complex cell-based systems, including human intestinal organoids and immortalized myeloid progenitor cells that can be differentiated into neutrophils, to study how Y. pseudotuberculosis and the Yops, impact intestinal tissues and neutrophils during infection.  Klebsiella pneumoniae causes a variety of diseases, most notably pneumonia, urinary tract infections, liver abscesses and blood stream infections. Many strains are now multi-drug resistant rendering these infections hard to treat. Using murine model systems of infection and high-throughput genetic screens, we are investigated how different components of the host immune system control Klebsiella and how Klebsiella has different nutritional requirements depending on the infected tissue.  Using this knowledge, we are evaluating how combinations of antibiotics function in different tissue environments to halt the growth of multidrug resistant Klebsiella

Lab members: