Evaluation of the effectiveness of packed red blood cell irradiation by a linear accelerator

Abstract

Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a linear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components.The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25 Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram.Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time.The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells.

Irradiation with x‐rays of the energy 18 MV induces radioactivity in transfusion blood: Proposal of a safe method using 6 MV

“…15 Previous scientific work had shown clearly that there is no significant difference in the biochemical effects of xirradiation compared to gamma irradiation of blood or blood components. 6,[11][12][13] The results of our study confirm this observation as long as the maximum x-ray energy of 6 MV is not exceeded. Moreover, we agree with many authors in the field 8-12 that x-rays from the linear accelerator are a safe and feasible alternative to gamma rays for blood irradiation.…”

“…11 Lots of scientific work was done to prove that the xrays from the linear accelerator achieve the same results as the irradiation with gamma rays. [11][12][13] However, the use of high energy x-rays may carry the potential risk of induced radioactivity in the irradiated blood which is planned to be transfused. This nuclear physical effect occurs when radiation with high energy removes a neutron or a proton from the nucleus of an atom [called (γ,n)-or (γ,p)-reaction] and induces radioactivity.…”

“…Typical devicespecific energy levels in routine clinical settings are 6 and 18 MV (MV: Megavolt), and one might prefer to use the higher energy to provide a more uniform radiation of the blood packets and possibly save time. Yet, in previously published reports, the x-ray energy was either specified as 6 MV, [8][9][10]13 or it was not mentioned at all. 6,11,12,14 Studies on the correlation between the energy of x-rays and the induced radioactivity in irradiated blood are missing.…”

Nanostructural Changes in the Cell Membrane of Gamma-Irradiated Red Blood Cells

“…Although the use of gamma radiation is routine worldwide, there are no unified standards for the gamma radiation dose [5], so the recommended dose varies between 25 and 50 Gy [6]. Such high doses may have deleterious effects on the quality of the blood components [7]. For example, the rate of efflux of intracellular potassium, sodium and hemoglobin increases following the irradiation of RBC, which may lead to a reduction in the RBC shelf-life [8][9][10].…”

Using a radiation therapy LINAC as a backup system for providing irradiated blood products

“…Irradiation of cellular blood components prevents transfusion‐associated graft‐versus‐host disease, but modern x‐ray blood irradiators occasionally fail. Having a backup system is important to support the activity of a blood bank in a large hospital with infants and cancer patients . Fig.…”