Irradiation of blood components in combating transfusion associated graft versus host disease (TA- GvHD)

Irradiation of cellular blood components is a specialized procedure performed to reduce one of the unusual but most serious adverse effects of transfusion therapy or transplantation, that is, transfusion-associated graft- versus-host disease (TA-GvHD). It is done using either gamma-rays or X-rays derived from radioactive sources. Various developed countries such as Great Britain, New Zealand, Australia, Canada, and Japan follow policies and guidelines for practicing transfusion of irradiated cellular blood components. In India, there are recommendations for the clinical use of irradiated blood components in indicated recipients. However, there is a lack of awareness about this specialized product, availability, usage, and its clinical importance. Furthermore, there are a few pros and cons of irradiating the blood components that need to be discussed. Most of the blood transfusion services departments or blood banks are not having in-house facilities of irradiation due to various reasons. There is a paucity of data published in literature based on clinical trials and evidences for the prevention of graft-versus-host disease by irradiation, and it mostly relies on case reports, hemovigilance data, and laboratory methods aiming to inactivate or eliminate lymphocytes in the transfused components. With this review article, we have made an attempt to describe the role of irradiation of blood components and its uses in the prevention of TA-GvHD, the different types of irradiators and methods of irradiation, dosimetry techniques, and the biochemical effect of irradiation on blood components. It will be helpful for peer clinicians to scrutinize the potential candidates for using irradiated blood components, considering its potential benefits.