T cells are necessary for defense against infections. Their role is to detect antigens that signal infection and mount an appropriate response. Activation begins with the signaling pathways from the T cell receptor (TCR) to a suite of transcription factors that induce the production of new genes, tuning the response to the specific invasion. NFAT is a transcription factor necessary for cell survival, proliferation, and effector function upon TCR stimulation. Its activation is markedly reduced in elderly populations, which leads to reduced efficacy of vaccinations in protecting against infection, and an increased risk of those infections without a preventative vaccine. A screen was performed for unknown activators of the NFAT pathway, and identified GEF-H1. Additional experiments revealed that GEF-H1is required for TCR signaling to NFAT. The goal of the outlined research is to show how GEF-H1 functions in the pathway. A strategy composed of three aims has been devised. Initially, steps in the TCR-to-NFAT pathway will be assayed in cells lacking GEF-H1 to determine what level in the pathway GEF-H1 acts. Next, the necessity of each domain in GEF-H1 will be tested for the restoration of NFAT activation in the GEF-H1 deficient cells. Finally, the role of the GEF-H1 target, RhoA, will be tested in the TCR pathway to NFAT. This research will expand our understanding of the regulation of T cells, and identify potential targets for the development of therapeutics to enhance sub-optimal immune responses seen in elderly patients.

Public Health Relevance

As we age our immune system becomes less effective. This research would expand our knowledge of how a healthy immune response works, so that we may develop targeted strategies for enhancing the sub-optimal responses seen in elderly patients.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
5F31AG043238-02
Application #
8521031
Study Section
Special Emphasis Panel (ZRG1-F07-E (20))
Program Officer
Fuldner, Rebecca A
Project Start
2012-09-01
Project End
2015-08-31
Budget Start
2013-09-01
Budget End
2014-08-31
Support Year
2
Fiscal Year
2013
Total Cost
$42,232
Indirect Cost
Name
Johns Hopkins University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Hamblet, Corinne E; Makowski, Stefanie L; Tritapoe, Julia M et al. (2016) NK Cell Maturation and Cytotoxicity Are Controlled by the Intramembrane Aspartyl Protease SPPL3. J Immunol 196:2614-26