Allogeneic Antigen Composition for Preparing Universal Cancer Vaccines

Figure 3

Efficacy I (a) and efficacy II (b) of target cell killing by SANTAVAC in CTA. Target HMEC were incubated in the presence of effector CTL at a 1 : 20 ratio. After 3 days, CTL were removed, target cells were carefully washed, and target cell viability was determined. Data is expressed as efficacy I (a) or efficacy II (b) of target cell killing by SANTAVAC. Efficacy I was calculated as a ratio of the number of nonstimulated cells in control wells (i.e., HMEC^0%) to the number of tumor-stimulated cells in experimental wells. Efficacy II was calculated as a ratio of the number of tumor-stimulated cells in control wells (i.e., HMEC^5%, HMEC^15%, or HMEC^25%) to the number of tumor-stimulated cells in experimental wells; that is, the percentage of tumor-conditioned medium in control wells was the same as in the experimental wells. Efficacy I allows in vitro estimation of the SANTAVAC efficacy by demonstrating how many endothelial cells in the tumor vasculature will be destroyed before 1 endothelial cell in normal tissue is destroyed (used to predict vaccine safety). Efficacy II allows in vitro estimation of the SANTAVAC efficacy by demonstrating the degree of HMEC proliferation suppression in the tumor vasculature and is used to establish the degree by which the vaccine can arrest tumor growth (predicted vaccine therapeutic effect). For efficacy calculation, the data representing the mean value of 3 independent measurements was used. “FAA” indicates the data related to the control (■) in CTA where fibroblast-associated antigens were used to simulate CTL. “swap” indicates CTA data where primary cell cultures used to generate antigens and primary cell cultures which were used as target cells were swapped (it was done to demonstrate the reproducibility of the CTA results at defined percentages of the tumor-conditioned medium used to stimulate HMEC). Percentage values indicated in the superscript correspond to the percentage of tumor-conditioned medium used to stimulate target HMEC or HMEC used to generate SANTAVAC for targeting immune response in CTA.

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