Differential role for IL‐7 in inducing lung Kruppel‐like factor (Kruppel‐like factor 2) expression by naive versus activated T cells

• Published in: International immunology 2003-11, Vol.15 (11), p.1341-1348
• Main Authors: Endrizzi, Bart T., Jameson, Stephen C.
• Format: Article
• Language: English
• Subjects: Animals; Cell Survival; cytokine; Genes, bcl-2 - genetics; homeostasis; Interleukin-12 - physiology; Interleukin-7 - physiology; Kruppel-Like Transcription Factors; Lymphocyte Activation; Mice; RNA, Messenger - immunology; RNA, Messenger - metabolism; survival; T cell; T-Lymphocytes - immunology; T-Lymphocytes - metabolism; Trans-Activators - biosynthesis; Trans-Activators - genetics; Trans-Activators - metabolism
• ISSN: 0953-8178; 1460-2377; 1460-2377
• DOI: 10.1093/intimm/dxg133

Kruppel‐like Factor 2 [KLF2, also called lung Kruppel‐like factor (LKLF)] is a transcription factor shown to be necessary for the maintenance of naive T cells. KLF2 is expressed in both naive and memory cells, and is proposed to promote quiescence in these populations. During T cell stimulation, both KLF2 protein and mRNA are down‐regulated, and loss of KLF2 appears to be critical for full T cell activation. It is unclear, however, how KLF2 expression is maintained in naive T cells. Recently it was proposed that IL‐7, which is known to promote KLF2 re‐expression in antigen‐stimulated T cells, may also induce KLF2 expression in naive T cells. Here we address this issue by comparing the impact of IL‐7 on KLF2 expression in naive and activated T cells. Use of bcl‐2 transgenic T cells allowed us to uncouple the requirements for IL‐7 in preserving naive T cell survival from its role in maintaining KLF2 expression. Our data demonstrates that IL‐7 signals are not required for KLF2 maintenance in naive T cells, suggesting that this cytokine has distinct effects on KLF2 expression in naive versus activated T cells.