Modeling for colony formation of human lens epithelial cells following ionizing radiation exposure

Oikawa, Joma*; Matsuya, Yusuke  ; Hamada, Nobuyuki*; Date, Hiroyuki*

To estimate the risk of radiation cataract following exposure to low dose of ionizing radiation is of importance. However, mechanisms of radiation cataract remain uncertain. Human lens epithelial cells (HLEC1) shows excessive proliferation after exposure above 2 Gy. In this regard, it is necessary for clarifying the relation between the excessive proliferation and the cataract induction. Here, we developed a cell colony model for HLEC1 based on in vitro experiments. We measured cell-cycle and cell growth curve, and then developed the colony model considering cell-cycle time and the limit of cell division number. As the results, we found that shorten the cell cycle time and multiple subpopulation of cells should be considered to reproduce the experimental colony size distribution. The experiments and model estimation suggest that the HLEC1 are heterogeneous population for growth, which may be influential to radiation cataract induction.