Kinetic analysis of epithelial cell migration in the colon on a massively parallel processor (CM-2)

A cell kinetic model of proliferating tissues and its implementation on the massively parallel computer, Connection Machine Model 2 (CM-2), is presented. The model is applicable to all proliferating tissues of the organism and is illustrated on the crypt-villus unit (CU) of the gastrointestinal mucosa. The crypt unit consists of two compartments, a progenitor (P) in which cells proliferate, and a proliferative quiescent (Q) compartment, in which cells are incapable of synthesizing DNA and therefore do not divide. Cells are formed in P, enter Q, traverse it, and die at its outer boundary. The healthy CU maintains a steady state; cell proliferation is controlled by cell elimination. The crypt cylinder is mapped onto a two-dimensional CM-2 matrix such that each processor represents a cell in the unit. The interprocessor links serve as proliferation controls. Using cell counts, the frequency of P cells in each cell location along the crypt column was estimated and various columnar kinetic parameters were calculated. The kinetic analysis shows that cell migration occurs along the crypt column in the direction of the colonic lumen at a velocity averaging 0.244 cell locations per hour. In order to compare model results with experimental kinetic studies, the model was used to stimulate a labeling experiment. The results are in agreement with published kinetic experiments that were done on a normal CU. The model allows three-dimensional visualization of the spatial and temporal events within the crypt.