Related Experiment Videos
Effect of dexamethasone on T-cell receptor/CD3 expression
G Migliorati1, A Bartoli, G Nocentini
1Department of Clinical Medicine, Pathology and Pharmacology, University of Perugia, Italy.
Molecular and Cellular Biochemistry
|February 1, 1997
Summary
Synthetic glucocorticoids like dexamethasone reduce T-cell receptor (TCR)/CD3 expression on T-lymphocytes. This downregulation is linked to decreased TCR zeta protein, not altered TCR/CD3 chain mRNA levels.
Area of Science:
- Immunology
- Molecular Biology
- Pharmacology
Background:
- Glucocorticoid hormones (GCH) possess anti-inflammatory and immunosuppressive properties.
- T-cell activation is mediated by the T-cell receptor (TCR)/CD3 complex.
Purpose of the Study:
- To investigate the in vitro effect of dexamethasone (DEX), a synthetic GCH, on TCR/CD3 expression in T-lymphocytes.
Main Methods:
- Treatment of T-cell lines and clones with DEX.
- Analysis of TCR/CD3 membrane expression.
- Quantification of TCR/CD3 chain mRNAs and CD3 epsilon protein.
- Assessment of TCR zeta gene products (mRNA and protein).
Main Results:
- DEX treatment decreased TCR/CD3 membrane expression in T-cells within 4 days, becoming undetectable after 4 weeks.
- Levels of mRNAs for TCR alpha, TCR beta, CD3 gamma, CD3 theta, and CD3 epsilon, as well as CD3 epsilon protein, remained unchanged.
- DEX induced a significant decrease in TCR zeta mRNA and protein levels.
Conclusions:
- Dexamethasone down-regulates TCR/CD3 expression on T-lymphocytes.
- The observed downregulation is attributed to the reduction in TCR zeta gene products, which are crucial for TCR/CD3 membrane expression.