Systems biology combines computational modeling with quantitative experimental measurements to study complex biological processes. Here, we outline an approach for parameterizing and validating a systems biology model to yield predictive tool that can generate testable hypotheses and expand biological understanding. CD3z CD16 NKG2D DAP10 2B4 CD 94 NK G2 A Activation 0 3 6 9 12 15 0.0 0.5 1.0 Time (min) Relative Amount of Phosphorylation Akt Erk Figure 2: Relative level of phosphorylated ERK (red) and Akt (blue) upon NKG2D stimulation. Lines, mean model predictions. Circles, experimental data. Shading, 95% confidence interval.