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Aging affects epidermal Langerhans cell development and function and alters their miRNA gene expression profile
Ying-Ping Xu1, Rui-Qun Qi, Wenbin Chen
1Henry Ford Immunology Program, Henry Ford Health System, Detroit, MI 48202, USA.
Aging
|November 27, 2012
Summary
Aging impairs skin immune cells called epidermal Langerhans cells (LCs). This study reveals age-related changes in LC development, function, and microRNA profiles, impacting T cell responses.
Area of Science:
- Immunology
- Dermatology
- Gerontology
Background:
- Immunosenescence, the age-related decline of immune function, affects various immune cells.
- Epidermal Langerhans cells (LCs) are crucial skin immune sentinels, but their aging process is not fully understood.
Purpose of the Study:
- To investigate the impact of aging on the development and function of epidermal LCs in mice.
- To explore age-associated changes in microRNA (miRNA) expression within LCs and their potential role in immune regulation.
Main Methods:
- Systematic analysis of LC development and function in young and aged C57BL/6J mice.
- Global miRNA gene expression profiling of aged versus young LCs.
- Assessment of LC maturation markers, phagocytosis, migration, and T cell proliferation induction.
Main Results:
- Aged mice (≥12 months) showed reduced frequency and maturation of epidermal LCs compared to young mice (<6 months).
- Increased Langerin expression and Dextran phagocytosis were observed in aged LCs, while migration remained comparable.
- Aged LCs exhibited impaired ability to induce CD4+ and CD8+ T cell proliferation.
- Distinct miRNA expression profiles were identified in aged LCs, with potential targeting of TGF-β signaling pathways.
Conclusions:
- Aging significantly alters epidermal LC development and function, characterized by reduced maturation but increased certain markers and impaired T cell stimulation.
- Age-regulated miRNAs in LCs may play a critical role in mediating the functional and developmental changes observed during aging.
- These findings provide insights into immunosenescence at the skin level and highlight potential miRNA-based therapeutic targets.
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