Calculating Target Cell Killing Constant

The value of k (the experimentally determined target cell killing constant) was calculated as previously described (Li et al., 2004 (link)) using Eq. 1 (b_t/b₀ = e^−kpt+gt). b_t = experimentally determined target cell concentration per milliliter of gel or tumor at time t (in minutes) of co-incubation of antigen-expressing target cells with antigen-specific CD8⁺ T cells in collagen-fibrin gels or inoculation of mice with antigen-specific CD8⁺ T cells. b₀ = initial target cell concentration per ml gel or tumor. The CD8⁺ CTC was calculated using Eq. 2 (Li et al., 2004 (link); CTC = g/k). g = the experimentally determined rate of B16 cell growth in vitro or in vivo or of increase in polyoma virus–infected target cells, calculated using the relationship ln b_t/b₀ = g × t (min). We estimated mouse spleen volume and wet weight for LCMV infected mice to be 0.15 ml and 0.15 g, respectively, and 0.1 ml and 0.1 g, respectively, for polyoma virus–infected mice. B16 melanoma tumors contain 3 × 10⁸ B16 cells/ml or /g of tumor (Stephens and Peacock, 1978 (link)).