Xiao He, M.D., Ph.D.
Research Assistant Professor
About Xiao He, M.D., Ph.D.
Currently we are working on two newly identified genes:
Th-POK (T-helper-inducing POZ/Kruppel factor): T lymphocytes, further divided into 2 major subpopulations: CD4 helper and CD8 cytotoxic T cells, play a crucial role in control microbial infections and cancer development. Th-POK is a transcriptional factor, which we cloned from HD (CD4 helper deficiency) mutant mouse line. Th-POK functions as a master gene in determining the CD4 vs. CD8 T cell lineage choice. A point mutation in Th-POK gene results in all mature T cells becoming CD8 cells, while over-expression of this factor leads totally lack of CD8 T cells. We are looking for the up-stream regulator(s) and down-stream target(s) of Th-POK. In addition, aberrant expression of Th-POK causes T cell lymphoma. We are studying the underlying mechanisms towards tumor genesis.
CIIEM (MHC Class II Expression Modifier): Antigen presenting cells (APC) capture, process and present non-self antigens (from microorganisms or tumor cells) to T lymphocytes to initiate a specific immune response. MHC Class II proteins are expressed on cell surface of the professional APC (B cells, dendritic cells and macrophages). Human T cells also express MHC Class II products and present antigens. In many cases, T cells can present self-antigens and are implicated in autoimmune diseases. Using bioinformatics, a putative novel gene, CIIEM, was identified. We hypothesize that CIIEM can inhibit the expression of MHC Class II genes in mouse T cells. Cloning the full length CIIEM cDNA and investigating its biological function are in progress.
Selected Publications
- X. He, TA Woodford-Thomas, KG Johnson, DD Shah and ML Thomas, Targeting of CD45 Phosphatase Activity to Lipid Microdomains on the T Cell Surface Inhibits TCR Signaling, Eur. J. Immunol. 32: 2578, 2002
- http://www3.interscience.wiley.com/cgi-bin/fulltext/98016313/HTMLSTART
- X. He, X. He, VP Dave, Y. Zhang, E Nicolas, X. Hua, W. Xu, BA Roe and DJ Kappes, The Zinc Finger Transcription Factor Th-POK Regulates CD4 versus CD8 T lineage Commitment. Nature 433: 826, 2005
- http://www.nature.com/nature/journal/v433/n7028/full/nature03338.html
- X. He and DJ Kappes, CD4/CD8 lineage commitment: Light at the end of the tunnel? Current Opinion in Immunology, 18(2): 135, 2006
- http://www.sciencedirect.com/science
- All Publications: Click Here
Professional Education
- 1978-1982 School of Medicine, Chongqing Medical College M.D.
- 1982-1985 Department of Pathophysiology, School of Graduate Studies,Shanghai Medical University M.S. in Immunology
- 1987-1990 Department of Microbiology & Immunology
- 1992-1996 Graduate School of Medical Sciences, Medical College of Pennsylvania, Ph.D. in Immunology

