[Effect of ionizing radiation of cobalt 60 on radiosensitivity of HeLa cells infected with Measles virus]

Radiotherapy is one of the cancer treatment methods. Prescribed dose for each fraction is considered based on radiosensitivity of tumoral and normal tissues. Viral agents are the effective factors on tissue sensitivity. This research aimed to determine the effect of ionizing radiation of Cobal 60 on radiosensitivity of Hela cells infected with Measles virus. In this study, the radiosensitivity of Hela cells is investigated experimentally and qualitively. The cells have been cultivated in two groups [experimental and blank] and plating efficiency has been obtained. Then 100 lambda measles virus with serial dilution method was used to induce infection in different ratio for experimental group. After cell growth and passage, the two groups were irradiated with 2Gy gamma radiation of cobalt 60. Results respectively indicated cell death increases up to 5-7%, 15-20% and 50-65%, after 2Gy irradiation by Co 60 for contaminating to Measles in low, moderate and high concentrations. The result in radiotherapy of cancers showed, in prescribing dose fraction non cancer disease should be considered

[Evaluation of radiosensitivity of HeLa cells infected with polio virus irradiated by Co 60]

The main purpose of radiotherapy is exposing enough doses of radiation to tumor tissue and protecting the normal tissues around it. Tumor dose for each session in radiotherapy will be considered based on radiosensitivity of the tissues. The presence of viral diseases in tumoral area can affect the radiosensitivity of cells. This study aimed to evaluate the radiosensitivity of Hela cells infected with poliomyelitis virus irradiated by Co 60. In this study, the radiosensitivity of HeLa cells, with or without the viral infection, after gamma radiation of cobalt 60, was assessed. Results of comparison of the radisensitivity of infected and uninfected cells indicates that after 2 Gy irradiation by Co 60, polio infection in low, moderate and high virus load, increases the cell death by 20-30%, 30-40% and 70-90% respectively. Radiosensitivity of tumoral cells increase when they are infected with viral agents. Results of this study showed that non cancer diseases should be considered when prescribing dose fraction in radiotherapy of cancers