Document Detail

Cellular interactions in thymocyte development.
MedLine Citation:
PMID:  8717508     Owner:  NLM     Status:  MEDLINE    
Interactions between stromal cells and thymocytes play a crucial role in T cell development. The thymic stroma is complex and consists of epithelial cells derived from the pharyngeal region during development, together with macrophages and dendritic cells of bone marrow origin. In addition, fibroblasts and matrix molecules permeate the whole framework. It is now apparent that these individual stromal components play specialized roles at different stages of T cell differentiation. Thus, at the early CD4-8- stage of development, T cell precursors require fibroblast as well as epithelial cell interactions. Later, at the CD4+8+ stage, as well as providing low avidity TCR/MHC-peptide interactions, thymic epithelial cells have been shown to possess unique properties essential for positive selection. Dendritic cells, on the other hand, are probably efficient mediators of negative selection, but they may not be solely responsible for this activity. Alongside the functional roles of stromal cells, considerable progress is being made in unraveling the nature of the signaling pathways involved in T cell development. Identification of the pre-T cell receptor (pre-TCR) and associated signaling molecules marks an important advance in understanding the mechanisms that control gene rearrangement and allelic exclusion. In addition, a better understanding of the signaling pathways that lead to positive selection on the one hand and negative selection on the other is beginning to emerge. Many issues remain unresolved, and some are discussed in this review. What, for example, is the nature of the chemotactic factor(s) that attract stem cells to the thymus? What is the molecular basis of the essential interactions between early thymocytes and fibroblasts, and early thymocytes and epithelial cells? What is special about cortical epithelial cells in supporting positive selection? These and other issues are ripe for analysis and can now be approached using a combination of modern molecular and cellular techniques.
G Anderson; N C Moore; J J Owen; E J Jenkinson
Related Documents :
6129278 - Modulation of tthy alloantigen expression in the neonatal mouse. the tthy-bearing thymo...
11120788 - Mhc recognition in thymic development: distinct, parallel pathways for survival and lin...
1719558 - Ligand-stimulated signaling events in immature cd4+cd8+ thymocytes expressing competent...
10423698 - Flow cytometric analysis of thymocyte subpopulations in mice after whole-body x-irradia...
22271448 - Dual-targeting immunotherapy of lymphoma: potent cytotoxicity of anti-cd20/cd74 bispeci...
17599038 - Tacc3 depletion sensitizes to paclitaxel-induced cell death and overrides p21waf-mediat...
Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  Annual review of immunology     Volume:  14     ISSN:  0732-0582     ISO Abbreviation:  Annu. Rev. Immunol.     Publication Date:  1996  
Date Detail:
Created Date:  1996-12-24     Completed Date:  1996-12-24     Revised Date:  2005-11-16    
Medline Journal Info:
Nlm Unique ID:  8309206     Medline TA:  Annu Rev Immunol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  73-99     Citation Subset:  IM    
Department of Anatomy, Medical School, University of Birmingham, United Kingdom.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cell Communication / immunology*
Cell Differentiation / immunology
T-Lymphocytes / cytology*,  immunology,  physiology*
Thymus Gland / cytology*,  immunology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Immunotoxins: an update.
Next Document:  One step ahead of the game: viral immunomodulatory molecules.