Radiation-induced Bystander Effect in Immune Response1
نویسندگان
چکیده
Objective Since most reports on bystander effect have been only concerned with radiation-induced damage, the present paper aimed at disclosing whether low dose radiation could induce a stimulatory or beneficial bystander effect. Methods A co-culture system containing irradiated antigen presenting cells (J774A.1) and unirradiated T lymphocytes (EL-4) was established to observe the effect of J774A.1 cells exposed to both low and high doses of X-rays on the unirradiated EL-4 cells. Incorporation of H-TdR was used to assess the proliferation of the EL-4 cells, expression of CD80/86 and CD48 on J774A.1 cells was measured with immunohistochemistry and flow cytometry, respectively. NO release from J774A.1 cells was estimated with nitrate reduction method. Results Low dose-irradiated J774A.1 cells could stimulate the proliferation of the unirradiated EL-4 cells while the high dose-irradiated J774A.1 cells exerted an inhibitory effect on the proliferation of the unirradiated EL-4 cells. Preliminary mechanistic studies illustrated that the differential changes in CD48 expression and NO production by the irradiated J774A.1 cells after high and low dose radiation might be important factors underlying the differential bystander effect elicited by different doses of radiation. Conclusion Stimulatory bystander effect can be induced in immune cells by low dose radiation.
منابع مشابه
The Mechanisms of Radiation-Induced Bystander Effect
The radiation-induced bystander effect is the phenomenon which non-irradiated cells exhibit effects along with their different levels as a result of signals received from nearby irradiated cells. Responses of non-irradiated cells may include changes in process of translation, gene expression, cell proliferation, apoptosis and cells death. These changes are confirmed by results of some In-Vivo s...
متن کاملRadiation Bystander Effects Mechanism
Introduction: Radiation Induced Bystander Effect (RIBE) which cause radiation effects in non-irradiated cells, has challenged the principle according to which radiation traversal through the nucleus of a cell is necessary for producing biological responses. What is the mechanism of this phenomenon? To have a better understanding of this rather ambiguous concept substantial number of original ...
متن کاملRadiation Induced Bystander Effect
Introduction: Radiation effects observed in cells that are not irradiated are known as non-targeted effects. Radiation induced bystander effect (RIBE) as a kind of non-targeted effect has been introduced in recent years. RIBE occurs in unexposed cells which are related to adjacent or distant irradiated cells. RIBE contradict with "target theory" which necessitates radiation tr...
متن کاملThe Role of Target and Bystander Cells in Dose-Response Relationship of Radiation-Induced Bystander Effects in Two Cell Lines
متن کامل
Radiation-induced Non-targeted Effect and Carcinogenesis; Implications in Clinical Radiotherapy
Bystander or non-targeted effect is known to be an interesting phenomenon in radiobiology. The genetic consequences of bystander effect on non-irradiated cells have shown that this phenomenon can be considered as one of the most important factors involved in secondary cancer after exposure to ionizing radiation. Every year, millions of people around the world undergo radiotherapy in order to cu...
متن کامل