Post-Irradiation Recovery of B14-150 Fibrosarcoma Cells after Combined Irradiation with Low and High Linear Energy Transfer

The use of radiation with low and high linear energy transfer (LET) in the same treatment regimen is promising in terms of increasing the efficiency and reducing the severity of radiation complications. Here we studied combined effect of protons (LET≈3 keV/μm) and heavy recoils (HR) induced by 14.5 MeV neutrons (LET≈290 keV/μm) on B14-150 fibrosarcoma cells. Comparison of the 4 irradiation schemes with different high-LET/low-LET dose ratios and the irradiation sequences revealed higher effectiveness of the combined action in the HR→protons sequence and with increasing HR dose contribution to 40% of the total dose. The observed effects were due to differences in the recovery of damages induced in cells by radiations with low and high LET.