Abstract
CD8(+) cytotoxic T lymphocytes (CTL) are key determinants of immunity to intracellular pathogens and neoplastic cells. Recognition of specific antigens in the form of peptide-MHC class I complexes (pMHCI) presented on the target cell surface is mediated by T cell receptor (TCR) engagement. The CD8 coreceptor binds to invariant domains of pMHCI and facilitates antigen recognition. Here, we investigate the biological effects of a Q115E substitution in the alpha2 domain of human leukocyte antigen (HLA)-A*0201 that enhances CD8 binding by approximately 50% without altering TCR/pMHCI interactions. Soluble and cell surface-expressed forms of Q115E HLA-A*0201 exhibit enhanced recognition by CTL without loss of specificity. These CD8-enhanced antigens induce greater CD3 zeta chain phosphorylation in cognate CTL leading to substantial increases in cytokine production, proliferation and priming of naive T cells. This effect provides a fundamental new mechanism with which to enhance cellular immunity to specific T cell antigens.
Original language | English |
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Pages (from-to) | 1323-33 |
Number of pages | 11 |
Journal | European Journal of Immunology |
Volume | 37 |
Issue number | 5 |
DOIs | |
Publication status | Published - May 2007 |
Keywords
- Amino Acid Sequence
- Antigen Presentation
- Antigens, CD8
- Epitopes, T-Lymphocyte
- HLA-A Antigens
- HLA-A2 Antigen
- Humans
- Lymphocyte Activation
- Molecular Sequence Data
- Mutation
- Protein Structure, Quaternary
- Receptors, Antigen, T-Cell
- Surface Plasmon Resonance
- T-Lymphocytes, Cytotoxic
- Transfection