Figure 1.

Two-dimensional (2D) T cell receptor (TCR)/pMHC affinity and kinetics of HCV-specific CD8+ T cell clones. (A) Schematics of different peptides and MHC mutants used to measure TCR/pMHC interaction and non-specific interaction control. (B) Average adhesion frequency for three examples of 2D TCR membrane kinetics of functional HCV-specific precursor CTLs. Non-specific adhesion was measured on TCR12 by quantifying TCR interaction with red blood cell conjugated with pMHC-CD8mut-preproinsulin (PPI) at same contact times as used in 2D TCR affinity measurements. Values of m_TCR and m_pMHC are the TCR and pMHC site density (molecules/μm2) for each respective CTL when measurement was performed. (C) 2D TCR affinity was calculated using Eq. 3, in Section “Materials and Methods,” for all functional HCV-specific CTLs and were depicted in order of ascending TCR affinity. Filled bars represent the 2D TCR affinity of the three example TCRs in (B) with matching symbols. (D) 2D TCR on-rate in order of ascending TCR affinity. 2D TCR on-rate was calculated using Eq. 2, in Section “Materials and Methods,” and TCR off-rate. Filled bars with symbols indicating individual TCRs depicted in (B). (E) 2D TCR off-rate in order of ascending TCR affinity. 2D TCR off-rate was calculated using Chi-squared curve fitting of the 2D TCR membrane kinetic curves for each CTL, respectively. Filled bars denoting TCRs depicted in (B). All data shown as mean ± SD of at least three cell pairs.