Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 287, Issue 27, Pages 23068-23078Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M112.357673
Keywords
-
Categories
Funding
- Swiss National Center of Competence in Research
- Swiss National Science foundation [3200B0-103173, 3200B0-118123]
- OncoSuisse [OCS 01381-08-2003, 02555-02-2010]
Ask authors/readers for more resources
Through a rational design approach, we generated a panel of HLA-A*0201/NY-ESO-1(157-165)-specific T cell receptors (TCR) with increasing affinities of up to 150-fold from the wild-type TCR. Using these TCR variants which extend just beyond the natural affinity range, along with an extreme supraphysiologic one having 1400-fold enhanced affinity, and a low-binding one, we sought to determine the effect of TCR binding properties along with cognate peptide concentration on CD8(+) T cell responsiveness. Major histocompatibility complexes (MHC) expressed on the surface of various antigen presenting cells were peptide-pulsed and used to stimulate human CD8(+) T cells expressing the different TCR via lentiviral transduction. At intermediate peptide concentration we measured maximum cytokine/chemokine secretion, cytotoxicity, and Ca2+ flux for CD8(+) T cells expressing TCR within a dissociation constant (K-D) range of similar to 1-5 mu M. Under these same conditions there was a gradual attenuation in activity for supraphysiologic affinity TCR with K-D < similar to 1 mu M, irrespective of CD8 co-engagement and of half-life (t(1/2) = ln 2/k(off)) values. With increased peptide concentration, however, the activity levels of CD8(+) T cells expressing supraphysiologic affinity TCR were gradually restored. Together our data support the productive hit rate model of T cell activation arguing that it is not the absolute number of TCR/pMHC complexes formed at equilibrium, but rather their productive turnover, that controls levels of biological activity. Our findings have important implications for various immunotherapies under development such as adoptive cell transfer of TCR-engineered CD8(+) T cells, as well as for peptide vaccination strategies.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available