Differential role for IL-7 in inducing lung Kruppel-like factor (Kruppel-like factor 2) expression by naive versus activated T cells.
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.
Endrizzi
Bart T
BT
Center for Immunology and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA.
Jameson
Stephen C
SC
D000818:Animals; D002470:Cell Survival; D019254:Genes, bcl-2 / Q000235:genetics; D018664:Interleukin-12 / Q000502:physiology; D015851:Interleukin-7 / Q000502:physiology*; D051741:Kruppel-Like Transcription Factors; D008213:Lymphocyte Activation; D051379:Mice; D012333:RNA, Messenger / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
D015851:Interleukin-7; C498314:Klf2 protein, mouse; D051741:Kruppel-Like Transcription Factors; D012333:RNA, Messenger; D015534:Trans-Activators; D018664:Interleukin-12