Immunosenescence starts from thymic involution, while age-related thymic involution results from thymic microenvironment changes regulated by multiple genes. Our hypothesis is the aged atrophic thymus must show changes in molecular features and cellular profiles that are not currently known, and transcription factors regulating thymic microenvironment built up mostly by thymic epithelial cells might be involved in the aging-related thymic involution process. Our approach is to investigate the aged atrophic thymus molecular features and cellular profiles focusing on K5/K8 co-localization on thymic epithelial cells, TN.1 hematopoietic progenitor cell subsets based on cKit and HAS expression, as well as the expression of two classes of Foxnl transcription; meanwhile test whether down regulation of the Foxnl signal in medulla, cortex and total TECs in adult thymus can sufficiently induce aging-related thymic involution with site- and time- tissue-specific Cre-recombinase mouse model. These studies may ultimately lead to understanding the molecular mechanisms of age-related thymic involution and make possible strategies to reverse the function of the aged thymus. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI064939-03
Application #
7028910
Study Section
Cellular and Molecular Immunology - B (CMI)
Program Officer
Deckhut Augustine, Alison M
Project Start
2005-04-01
Project End
2008-03-31
Budget Start
2006-04-01
Budget End
2008-03-31
Support Year
3
Fiscal Year
2006
Total Cost
$201,403
Indirect Cost
Name
University of Texas Health Center at Tyler
Department
Type
Organized Research Units
DUNS #
800772337
City
Tyler
State
TX
Country
United States
Zip Code
75708
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Zhu, Xike; Gui, Jingang; Dohkan, Junichi et al. (2007) Lymphohematopoietic progenitors do not have a synchronized defect with age-related thymic involution. Aging Cell 6:663-72
Gui, Jingang; Zhu, Xike; Dohkan, Junichi et al. (2007) The aged thymus shows normal recruitment of lymphohematopoietic progenitors but has defects in thymic epithelial cells. Int Immunol 19:1201-11