Konstantina Alexandropoulos, PhD
img_Konstantina Alexandropoulos
ASSOCIATE PROFESSOR | Medicine, Clinical Immunology
ASSOCIATE PROFESSOR | Medicine, Liver Diseases
Research Topics
Autoimmunity, Cell Adhesion, Cell Motility, Chemokines, Chemotaxis, Epithelial Cells, Immunological Tolerance, Immunology, Inflammation, Integrins, Lipid Signaling, Migration, Protein Kinases, Signal Transduction, T Cells, Tolerance, Trafficking, Transplantation
Multi-Disciplinary Training Area
Immunology [IMM]

Research Interests:

Konstantina Alexandropoulos, PhD, is the Director of the T-cell Mediated Autoimmunity and Inflammation Laboratory. The laboratory focuses on elucidating several aspects of T cell physiology including T cell development, activation and trafficking under physiologic and disease conditions.

One major focus of our research is directed towards understanding the processes that cause aberrant T cell function and T cell-mediated autoimmune diseases exemplified by conditions such as rheumatoid arthritis, inflammatory bowel disease and diabetes. Under normal conditions, developing T cells in the thymus are educated not to attack the body's own tissues in a process known as T cell tolerance. T cell tolerance is exerted through two different mechanisms: a) elimination of mature, self-reactive T cells in the thymus (central tolerance); b) intrathymic generation of regulatory T cells which in peripheral tissues suppress the activity of self-reactive T cells that escape destruction in the thymus (peripheral tolerance). Establishment of both central and peripheral tolerance occurs in the thymus and is highly dependent on reciprocal interactions between developing T cells and the thymic epithelium, specifically medullary thymic epithelial cells (mTECs). Disruption of these interactions leads to aberrant elimination of autoreactive T cell clones, defective peripheral tolerance and autoimmunity, manifested as T cell-containing inflammatory infiltrates in and autoantibody production against peripheral tissues. We are currently using different mouse models with mutations that disrupt the development of mTECs to understand how disruption of thymic cross-talk between the medullary epithelium and T cells affects T cell development and autoimmunity. 

Another area of research in the laboratory concentrates on elucidating the cellular and molecular mechanisms that regulate T cell activation and migration during the initiation and establishment of an immune response respectively. In these studies we are using knockout mice lacking expression of novel signaling proteins we previously characterized to study how these proteins regulate T cell activation, migration, and T cell-mediated immune responses under normal or inflammatory conditions. Our studies using mouse models coupled with molecular and biochemical approaches serve as a platform towards elucidating basic aspects of T cell physiology and are aimed towards identifying novel therapeutic targets to control the behavior of T cells in inflammation and autoimmunity.

PhD, City University of New York (CUNY)

Massachusetts Institute of Technology

Rockefeller University


Selected Publications

Impaired central tolerance induces changes in the gut microbiota that exacerbate autoimmune hepatitis. Monica Centa, Jose C. Clemente, Jeremiah J. Faith, M. Isabel Fiel, Konstantina Alexandropoulos. Journal of Autoimmunity

Immunology of COVID-19: Current State of the Science. Nicolas Vabret, Graham J. Britton, Conor Gruber, Samarth Hegde, Rachel Levantovsky, Luisanna Pia, Miriam Saffern, Bérengère Salomé, Jessica Tan, Verena van der Heide, Konstantina Alexandropoulos, Nina Bhardwaj, Brian D. Brown, Benjamin Greenbaum, Zeynep H. Gümüş, Dirk Homann, Amir Horowitz, Alice O. Kamphorst, Maria A. Curotto de Lafaille, Saurabh Mehandru, Miriam Merad, Robert M. Samstein, Manasi Agrawal, Mark Aleynick, Matthew Brown, Maria Casanova-Acebes, Andrew Chan, Evan Cody, Nicolas Fernandez, John Grout, Dan Fu Ruan, Pauline Hamon, Etienne Humblin, Divya Jha, Matthew Lin, Katherine Lindblad, Gabrielle Lubitz, Justine Noel, Tim O'Donnell, Venu Pothula, Jamie Redes, Ivan Reyes Torres, Joan Shang, Maria Suprun, Michelle Tran, Natalie Vaninov, Julio Aguirre-Ghiso, Dusan Bogunovic, Jeremiah Faith, Emilie Grasset, Peter Heeger, Ephraim Kenigsberg, Florian Krammer, Uri Laserson. Immunity

Advancing scientific knowledge in times of pandemics. Nicolas Vabret, Robert Samstein, Miriam Merad, Alfonso Rodriguez, Alvaro Moreira, Bérengère Salomé, Cansu Cimen Bozkus, Conor Gruber, Dan Fu Ruan, Daniel Lozano-Ojalvo, Divya Jha, Etienne Humblin, Evan Cody, Gabrielle Lubitz, Graham Britton, Jamie Redes, Jessica Tan, Joan Shang, John Grout, Justine Noel, Katherine Lindblad, Luisanna Pia, Manasi Agrawal, Maria Casanova-Acebes, Maria Suprun, Mark Aleynick, Matthew Brown, Matthew Lin, Miriam Saffern, Monica Centa, Natalie Vaninov, Nicolas Fernandez, Pauline Hamon, Rachel Levantovsky, Samarth Hegde, Venu Pothula, Verena Van Der Heide, Zafar Mahmood, Amir Horowitz, Brian Brown, Dirk Homann, Dusan Bogunovic, Emilie Grasset, Ephraim Kenigsberg, Jeremiah Faith, Konstantina Alexandropoulos, Nicolas Vabret, Nina Bhardwaj, Peter Heeger, Robert Samstein, Saurabh Mehandru, Uri Laserson. Nature Reviews Immunology

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Physicians and scientists on the faculty of the Icahn School of Medicine at Mount Sinai often interact with pharmaceutical, device and biotechnology companies to improve patient care, develop new therapies and achieve scientific breakthroughs. In order to promote an ethical and transparent environment for conducting research, providing clinical care and teaching, Mount Sinai requires that salaried faculty inform the School of their relationships with such companies.

Dr. Alexandropoulos did not report having any of the following types of financial relationships with industry during 2022 and/or 2023: consulting, scientific advisory board, industry-sponsored lectures, service on Board of Directors, participation on industry-sponsored committees, equity ownership valued at greater than 5% of a publicly traded company or any value in a privately held company. Please note that this information may differ from information posted on corporate sites due to timing or classification differences.

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