Modelling Calcium Signal Intensity Difference Between Cells

Abstract

Cell signaling involves the transmission of a signal from a sending cell to a receiving cell. Calcium ions (Ca²⁺) are a widely used type of messenger. In this study the evolution over time of calcium signal intensity and how these evolutions depend on the four groups of cells of subjects with different health condition was investigated. A longitudinal data analysis based on 110 subjects was used and to account non-linearity and correlated nature of the data, non-linear mixed model was used. Based on the exploratory data analysis result supported with CurveExpert professional software the model used has sigmoid structure. From the result, the rate of change of average signal intensity was nearly 0.033 and the time at which the rate of change of average calcium signal intensity reaches its maximum (i.e. the inflection point) was nearly 198 seconds. Furthermore, there were statistically significant differences in average calcium signal intensity between the groups. It is also observed that significant differences between mild hyperplasia and benign tumor patient’s cells and also between malignant tumor and healthy subject’s cells.

Keywords: Calcium, Cell Signaling, Non Linear Mixed Model, Random Effect, Signal Intensity