Esther Choi
e-mail address: estchoi@umich.edu

Mentor: Cheong-Hee Chang, Ph.D.

Research Description

CD4 T cells are known to be generated by their receptor association with MHC II peptide complexes on thymic epithelial cells. Recently, however, an alternate pathway for CD4 T cell development by MHC class II expressing thymocytes has been discovered. This selection process leads to the generation of a distinct CD4 T cell population named T-CD4 T cells (thymocyte-selected). Published data suggests that T-CD4 T cells are different from E-CD4 T cells (epithelial cell-selected) in that T-CD4 T cells can produce IL-4 in Th0 (un-skewed) environment. Interestingly, T-CD4 T cells also produce IL-4 in addition to IFN g after being skewed to become Th1 cells. Furthermore, T-CD4 T cells are able to produce Th2 cytokines independent of Stat6 necessary for Th2 differentiation in E-CD4 T cells. Although T-CD4 T cells exhibit a similar phenotype to NKT cells T-CD4 T cells need MHC class II not CD1d to develop. Also, unlike NKT cells, T-CD4 T cells lack NK1.1. We have observed in the context of allergen induced airway inflammation, that the presence of T-CD4 T cells decreases Th2 response and airway inflammation.

It is not yet clear, however, whether T-CD4 T cell s themselves are responsible for the resistance of allergic airway inflammation. Moreover, relationships between T-CD4 T cells and other immune cells involved in allergic responses have not been investigated . Thus, I will be focusing on characterizing T-CD4 T cells in the context of allergen induced airway inflammation.

Publications

Awards

Rackham Merit Fellowship