Main Session
Sep
30
PQA 09 - Hematologic Malignancies, Health Services Research, Digital Health Innovation and Informatics
3681 - Rapid Sterilization of Clinical Apheresis Blood Products using Ultra-High Dose Rate Radiation
Presenter(s)
Stavros Melemenidis, PhD - Anschutz Cancer Pavilion, Aurora, CO
S. Melemenidis1, K. D. Nguyen2, R. B. P. P. Baraceros-Pineda3, C. K. Barclay2, J. Bautista2, H. Lau3, M. R. M. Ashraf1, R. Manjappa1, S. Dutt1, L. A. Soto1, N. Katila1, B. Lau1, V. Viswanathan1, S. J. Yu1, M. Surucu4, L. Skinner1, E. G. Engleman2, T. D. Pham2, and B. W. Loo Jr5; 1Department of Radiation Oncology, Stanford University, Palo Alto, CA, 2Stanford Blood Center, Stanford Health Care, Palo Alto, CA, 3Department of Health Policy, Center for Innovation to Implementation, Veterans Affairs Health Care, Palo Alto, CA, 4Department of Radiation Oncology, Stanford University, Stanford, CA, 5Stanford University, Palo Alto, CA
Purpose/Objective(s):
Blood products, including apheresis platelets and plasma, are indispensable in clinical practice yet are inherently vulnerable to bacterial contamination and viral transmission. Platelets, stored at room temperature to preserve function, provide a conducive environment for bacterial proliferation, whereas plasma requires extensive screening to minimize infectious risks. This study investigates the feasibility of using ultra-high dose rate (UHDR) irradiation, delivered via a clinical linear accelerator, as an innovative and rapid pathogen reduction strategy for blood products.Materials/Methods:
A technology company treatment delivery system clinical linear accelerator was reconfigured to deliver UHDR irradiation at approximately 6 kGy/min. A series of experiments were conducted on apheresis-derived platelet components and COVID Convalescent Plasma (CCP). Platelet aliquots, spiked with ~105 CFU/mL of E. coli, were exposed to a graduated range of doses from 0.1 to 20 kGy. Subsequent analyses included quantitative bacterial colony-forming unit (CFU) assays and automated platelet counts to evaluate the impact of irradiation on microbial inactivation and cellular integrity. In parallel, CCP samples were irradiated at a sterilizing dose of 25 kGy, and the retention of immunologic function was assessed by measuring SARS-CoV-2 Receptor Binding Domain (RBD)-specific IgG antibody binding via ELISA. Dosimetric evaluations ensured a uniform beam profile (with <5% variation) and accurate dose mapping across the sample holder.Results:
UHDR irradiation at 1 kGy produced a significant 2.7-log reduction in E. coli growth without appreciable loss of platelet count. Complete bacterial suppression was observed at 5 kGy, while extrapolation from the exponential decay fit indicated that a 6-log reduction (sterilizing dose) would be achieved at approximately 2.3 kGy, albeit with an estimated 31% reduction in platelet count. Importantly, irradiation of CCP at 25 kGy resulted in only a modest 9.2% decrease in RBD-specific IgG binding, suggesting that key protein structures were largely preserved despite the high sterilizing dose.Conclusion:
These findings provide a compelling proof-of-concept for rapid blood sterilization using UHDR irradiation delivered by a clinical linear accelerator. The data demonstrate that this approach can achieve effective bacterial and viral inactivation while maintaining acceptable levels of platelet viability and antibody function. Given its speed, simplicity, and point-of-care applicability, UHDR irradiation represents a promising alternative to conventional pathogen reduction technologies for improving the safety of transfusion products. Future studies will focus on further optimization and validation across a broader spectrum of clinically relevant pathogens and functional assays of blood component integrity.