Open AccessDeclining expression of a single epithelial cell‐autonomous gene accelerates age‐related thymic involution
Author(s) -
Sun Liguang,
Guo Jianfei,
Brown Robert,
Amagai Takashi,
Zhao Yong,
Su DongMing
Publication year - 2010
Publication title -
aging cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.103
H-Index - 140
eISSN - 1474-9726
pISSN - 1474-9718
DOI - 10.1111/j.1474-9726.2010.00559.x
Subject(s) - thymic involution , involution (esoterism) , biology , phenotype , transgene , gene expression , t cell , gene , genetically modified mouse , economic shortage , microbiology and biotechnology , immunology , immune system , genetics , neuroscience , consciousness , linguistics , philosophy , government (linguistics)
Summary Age‐related thymic involution may be triggered by gene expression changes in lymphohematopoietic and/or nonhematopoietic thymic epithelial cells (TECs). The role of epithelial cell‐autonomous gene FoxN1 may be involved in the process, but it is still a puzzle because of the shortage of evidence from gradual loss‐of‐function and exogenous gain‐of‐function studies. Using our recently generated loxP ‐floxed‐ FoxN1 (fx) mouse carrying the ubiquitous CreER T (uCreER T ) transgene with a low dose of spontaneous activation, which causes gradual FoxN1 deletion with age, we found that the uCreER T ‐fx/fx mice showed an accelerated age‐related thymic involution owing to progressive loss of FoxN1 + TECs. The thymic aging phenotypes were clearly observable as early as at 3–6 months of age, resembling the naturally aged (18–22‐month‐old) murine thymus. By intrathymically supplying aged wild‐type mice with exogenous FoxN1‐cDNA, thymic involution and defective peripheral CD4 + T‐cell function could be partially rescued. The results support the notion that decline of a single epithelial cell‐autonomous gene FoxN1 levels with age causes primary deterioration in TECs followed by impairment of the total postnatal thymic microenvironment, and potentially triggers age‐related thymic involution in mice.