Apoptosis induced in non-hit bystander cells is an important biological mechanism which operates after exposure to low doses of low-LET radiation. This process was implemented into a deterministic multistage model for in vitro neoplastic transformation: the State-Vector Model (SVM). The new model is tested on two data sets that show a reduction of the transformation frequency below the spontaneous level after exposure of the human hybrid cell line CGL1 to low doses of γ-radiation. Stronger protective effects are visible in the data for delayed plating while the data for immediate plating show more of an LNTlike dose-response curve. It is shown that the model can describe both data sets. The calculation of the time-dependent numerical solution of the model also allows to obtain information about the time-dependence of the protective apoptosis-mediated process after low dose exposures. These findings are compared with experimental observations after high dose exposures.
Schöllnberger, Helmut and Eckl, Peter M
"PROTECTIVE BYSTANDER EFFECTS SIMULATED WITH THE STATE-VECTOR MODEL,"
Dose-Response: An International Journal:
3, Article 5.
Available at: http://scholarworks.umass.edu/dose_response/vol5/iss3/5