The in vitro quality of X‐irradiated platelet components in PAS‐E is equivalent to gamma‐irradiated components

Abstract

Background Blood components are irradiated to inactivate lymphocytes in an effort to prevent transfusion‐associated graft versus host disease. Although gamma irradiators are commonly used, they are subjected to rigorous health, safety, and compliance regulations, compared with X‐irradiators which have the advantage of only emitting radiation while the machine is switched on. While the effects of gamma irradiation on platelet components are well known, there is little or no data comparing the effects of X‐ and gamma‐irradiation on the quality of these components. Therefore, this study examined the in vitro quality of platelet components (pooled and apheresis) following X‐ or gamma‐irradiation. Study design and methods Whole‐blood‐derived (pooled) and apheresis platelet components in platelet additive solution (n = 20 pairs for each type) were irradiated (X vs. gamma). In vitro platelet quality was tested prior to irradiation (day 1) and subsequently on days 2, 5, and 7. Non‐irradiated components were tested on day 5 in parallel as reference controls. Metabolic parameters, surface expression of glycoproteins and activation markers (CD62P and annexin‐V binding), and agonist‐induced aggregation were measured. Results All components met Council of Europe specifications. There were no statistical differences in any in vitro quality measurements between X‐ and gamma‐irradiated pooled or apheresis platelet components. Conclusion X‐ and gamma‐irradiation have similar effects on the in vitro quality of stored blood components, indicating that either technology represents a suitable option for irradiation of platelet components.

Gamma and X‐ray irradiation do not affect the in vitro quality of refrigerated apheresis platelets in platelet additive solution (PAS‐E)

“…As expected, cold‐stored platelets retained their ability to aggregate in response to agonists throughout storage 5,59,60 . Importantly, irradiation, from either a gamma or X‐ray source, did not affect any in vitro parameter examined, which is consistent with what has been reported for RT‐stored irradiated platelet components 15–20 …”

“…49,50 Irradiation appears to have little impact on the standard metabolic (pH, glucose, lactate) or activation (CD62P, annexin-V) parameters during conventional platelet storage. [15][16][17][18][19][20] However, given the membrane alterations initiated by cold storage, including cytoskeletal modifications, alteration in microtubules, and ultimately a significant morphological change, 48,51,52 it seemed plausible that irradiation of platelets that had undergone these coldinduced modifications may result in further detrimental changes to the platelets, especially during extended storage. However, this was not the case.…”

“…5,59,60 Importantly, irradiation, from either a gamma or X-ray source, did not affect any in vitro parameter examined, which is consistent with what has been reported for RT-stored irradiated platelet components. [15][16][17][18][19][20] Of note, there is mounting evidence that irradiation may alter aspects of platelet quality that are only detectable using more specialized techniques. Proteomic investigations have shown that gamma irradiation alters the platelet proteome.…”

“…Gamma and X‐ray irradiation can be distinguished by the source from which they originate; where gamma rays are emitted from the radioactive decay of atomic nuclei, either Cesium‐137 (Cs‐137) or Cobalt‐60 (Co‐60); and X‐rays are a non‐isotopic form of radiation emitted when high‐velocity electrons strike a dense metal target. Irradiation, from either a gamma or X‐ray source, has minimal impact on platelet quality during conventional storage 15–21 . In contrast, the combination of cold storage and treatment with pathogen inactivation systems, which utilize UV‐light based non‐ionizing irradiation, with or without a photosensitizer, have been shown to significantly alter aspects of platelet quality, beyond the effects of either technique alone 22–24 .…”

“…Irradiation, from either a gamma or X-ray source, has minimal impact on platelet quality during conventional storage. [15][16][17][18][19][20][21] In contrast, the combination of cold storage and treatment with pathogen inactivation systems, which utilize UV-light based nonionizing irradiation, with or without a photosensitizer, have been shown to significantly alter aspects of platelet quality, beyond the effects of either technique alone. [22][23][24] While there are reports of platelets being irradiated prior to transfer to cold storage, 25,26 the effect of irradiation has not been directly assessed.…”