Analysis of Notch1 function by in vitro T cell differentiation of Pax5 mutant lymphoid progenitors

Autor: Hoflinger, S., Kesavan, K., Fuxa, M., Hutter, C., Heavey, B., Radtke, F., Meinrad Busslinger
Předmět:
Cell Lineage/genetics/immunology
Knockout
B-Lymphocyte Subsets/cytology/metabolism/physiology
Cell Differentiation/genetics/immunology
chemical and pharmacologic phenomena
DNA-Binding Proteins/*genetics/physiology
Signal Transduction/genetics/immunology
B-Cell-Specific Activator Protein
Inbred C57BL
Research Support
Cell Line
Mice
hemic and lymphatic diseases
Receptors
Animals
Stromal Cells/physiology
Non-U.S. Gov't
Notch1
Gene Expression Regulation/immunology
gamma-delta/genetics
hemic and immune systems
Mutation
Cell Surface/genetics/*physiology
T-Cell
T-Lymphocyte Subsets/*cytology/metabolism/*physiology
Coculture Techniques
Clone Cells
Antigen
Transcription Factors/*genetics/*physiology
Down-Regulation/genetics/immunology
alpha-beta/genetics
Stem Cells/*cytology/*metabolism/physiology
Receptor
Zdroj: ResearcherID
Popis: Signaling through the Notch1 receptor is essential for T cell development in the thymus. Stromal OP9 cells ectopically expressing the Notch ligand Delta-like1 mimic the thymic environment by inducing hemopoietic stem cells to undergo in vitro T cell development. Notch1 is also expressed on Pax5-/- pro-B cells, which are clonable lymphoid progenitors with a latent myeloid potential. In this study, we demonstrate that Pax5-/- progenitors efficiently differentiate in vitro into CD4+CD8+ alphabeta and gammadelta T cells upon coculture with OP9-Delta-like1 cells. In vitro T cell development of Pax5-/- progenitors strictly depends on Notch1 function and progresses through normal developmental stages by expressing T cell markers and rearranging TCRbeta, gamma, and delta loci in the correct temporal sequence. Notch-stimulated Pax5-/- progenitors efficiently down-regulate the expression of B cell-specific genes, consistent with a role of Notch1 in preventing B lymphopoiesis in the thymus. At the same time, Notch signaling rapidly induces cell surface expression of the c-Kit receptor and transcription of the target genes Deltex1 and pre-Talpha concomitant with the activation of TCR Vbeta germline transcription and the regulatory genes GATA3 and Tcf1. These data suggest that Notch1 acts upstream of GATA3 and Tcf1 in early T cell development and regulates Vbeta-DJbeta rearrangements by controlling the chromatin accessibility of Vbeta genes at the TCRbeta locus.
Databáze: OpenAIRE
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