Ehrlich studies the development of immune cells called T cells, which has implications for diseases such as T cell leukemia, autoimmunity, and most recently, COVID-19. Her lab is currently collaborating with investigators and clinicians at Dell Medical School to investigate which immune responses correlate with disease severity in COVID-19 patients across the lifespan. She is also studying links between SARS-CoV-2 infection and autoimmunity.

T cells are master regulators of the adaptive immune system: they are essential for coordinating the appropriate immune response to different pathogens, and they are responsible for immunologic memory, which protects us from recurrent infections. As T cells develop in the thymus, they encounter a wide variety of cells in their microenvironment, collectively referred to as the thymic stroma. Thymocytes and stromal cells are mutually dependant on each other for proper development and maintenance. Deviations in normal thymocyte: stromal interactions are thought to contribute to diseases such as T cell leukemia and autoimmunity.