Acknowledgments
1. Résumé en français
1.1 Les molécules du complexe majeur d'histocompatibilité classe II
1.2 L'expression des gènes CMH-II
1.3 Les cellules dendritiques
1.4 L'expression du gène
MHC2TA
dans les cellules dendritiques
1.5 L'analyse moléculaire du promoteur I de CIITA
1.6 Conclusions
2. Introduction
2.1 MHCII
2.1.1 MHCI versus MHCII molecules
2.1.2 The role of MHCII molecules in the immune response
2.1.3 The structure of MHCII molecules
2.1.4 The diversity of MHCII genes and their genomic organization
2.1.5 Polymorphism
2.1.6 Formation of MHCII-peptide complexes
2.1.7 Expression of MHCII molecules
2.2 Regulation of MHCII expression
Summary
Abstract
Introduction
The Bare Lymphocyte Syndrome
A disease resulting from the absence of MHCII expression
Genetic heterogeneity in the cause of BLS
Lessons from mouse models of BLS
Therapeutic strategies
Carrier detection and prenatal diagnosis for BLS
Gene therapy for BLS
RFX and CIITA as targets for novel immunomodulators
Tumor immunotherapy.
Regulation of MHCII expression
Overview
The RFX complex
The MHCII enhanceosome
The master regulator CIITA
Regulation of
MHC2TA
expression
The MHC2TA gene is controlled by multiple promoters
pI and expression of MHC2TA in DC
pIII and expression of MHC2TA in B cells
pIV and IFN-
g
induced MHC2TA expression
Lessons from pIV knockout mice
Structure and function of CIITA
Structure of CIITA
Recruitment of CIITA to the MHCII enhanceosome
Activation of transcription by CIITA
The GTP binding domain and the leucine rich repeat region
Dimerization of CIITA
Nuclear localization of CIITA
The role of CIITA and the enhanceosome in MHCI expression
Additional targets of CIITA
CIITA as a target of pathogens
Acknowledgments
References
2.3 Dendritic cells
2.3.1 The role of dendritic cells in the immune system
2.3.2 Immature dendritic cells
2.3.3 Dendritic cell activation and maturation
2.3.4 Antigen presentation by dendritic cells
2.3.5 T cell stimulation and tolerization by dendritic cells
3. Materials and methods
3.1 Preparation of monocytes and dendritic cells
3.2 Transduction of dendritic cells with lentiviral vectors
3.3 Cell lines
3.4 Embryonic stem cells
3.5 Cytofluorometry
3.6 RNA isolation
3.7 RNase protection assay
3.8 Real time PCR and RT-PCR.
3.9 Measurement of CIITA mRNA stability
3.10 Isolation of nascent RNAs
3.11
In vivo
genomic footprinting
3.12 Protein extracts
3.13 Immunoprecipitation and immunoblotting
3.14 Chromatin immunoprecipitation and quantification
3.15 Yeast-two-hybrid screening
4. Results
4.1 Expression and promoter usage of the
MHC2TA
gene in dendritic cells
4.1.1 Publication
4.1.2 Expression of CIITA during the differentiation of monocytes into dendritic cells
4.1.3 Occupation of the CIITA type I promoter in monocytes and immature dendritic cells
4.1.4 CIITA pI is not responsive to IFN-
g
in human peripheral monocytes
4.2 Molecular dissection of CIITA promoter I
4.2.1 Introduction
4.2.2 Gene transfer into dendritic cells
4.2.3 The first 390 base pairs of pI are sufficient for transcriptional activity in immature DCs
4.2.4 The minimal promoter region pI-390 is specific for cells of myeloid origin
4.2.5 The transcriptional activity of pI-390 does not change with DC maturation
4.2.6 Summary
4.3 CIITA pI knockout mice
4.4 Interaction partners of the N-terminus of dendritic cell-specific CIITA
5. Discussion : conclusions and perspectives
CIITA silencing in dendritic cells during maturation
MHC2TA
promoter usage
Molecular dissection of CIITA promoter I
References
Abbreviations