During fiscal year 2010 we accomplished the following: 1) We used Bim-deficient and Fas-deficient CD4+ T cells to dissect the contributions of mitochondrial and death receptor-initiated pathways of activation-induced cell death. We found that the COX2 inhibitor celecoxib increased mitochondria-dependent cell death without significantly affecting death-receptor initiated cell death. These observation were confirmed in CD4+ T cells from COX2-deficient mice. Gene expression changes in the presence of celecoxib were evaluated by microarray analysis of cells activated for different time periods in the presence or absence of the drug. 2) We found that earlier studies of Dicer-deficient cells were compromised by outgrowth of Dicer-sufficient cells during preparation of T cell blasts. These studies are currently being repeated with cells that express transgenic BclXL to prevent cell death during the first activation phase. 3) We used quantitative reverse-transcriptase PCR to identify changes in micro-RNA expression in cells activated for different time periods. These results will be evaluated in the context of responses of Dicer-deficient CD4+ T cells to identify the role of micro RNAs in regulating cell death.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Investigator-Initiated Intramural Research Projects (ZIA)
Project #
1ZIAAG000384-06
Application #
8148240
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
6
Fiscal Year
2010
Total Cost
$216,101
Indirect Cost
Name
National Institute on Aging
Department
Type
DUNS #
City
State
Country
Zip Code
Sen, Ranjan (2011) The origins of NF-?B. Nat Immunol 12:686-8
Munk, Rachel B; Sugiyama, Katsuki; Ghosh, Paritosh et al. (2011) Antigen-independent IFN-? production by human naïve CD4 T cells activated by IL-12 plus IL-18. PLoS One 6:e18553
Olkhanud, Purevdorj B; Damdinsuren, Bazarragchaa; Bodogai, Monica et al. (2011) Tumor-evoked regulatory B cells promote breast cancer metastasis by converting resting CD4? T cells to T-regulatory cells. Cancer Res 71:3505-15