Fig. 3.
The generalized cyton model. (A) Cell number over time is plotted for five different cyton configurations. Progressing from cyton plot 1 to 5, the median times to divide (φi>0) and die (ψi>0) in subsequent divisions are increased and decreased, respectively, by <20% (represented by the shaded area in cyton plots). These subtle shifts cause a large net change in the response from expansion (trace 1) to contraction (trace 5). Cyton parameter values: trace 1, φi>0 9, ψi>0 11; trace 2, φi>0 9, ψi>0 10.5; trace 3, φi>0 10, ψi>0 10.5; trace 4, φi>0 11, ψi>0 10.5; trace 5, φi>0 11, ψi>0 9. s is kept constant at 0.2 for all cyton plots. (B) B cells were labeled with CFSE and stimulated with 10 μg/ml α-CD40 and 500 units/ml IL-4. Cells were harvested at different times, and the total cell number as well as number of cells in each division was calculated. The optimal cyton solution is shown by dashed lines. Mean and SEM values of three replicates are shown. (C) Cyton solution of data shown in B. By using the data available, the cyton solution for time to death in subsequent divisions cannot be constrained.