11 research outputs found
Photodegradation of thionine in platelet concentrates by treatment with thionine/light and UVB
Bacterial survival in whole blood depends on plasma sensitivity and resistance to neutrophil killing
Evaluation of platelet concentrates prepared from whole blood donations with collection times between 12 and 15 min: The BEST Collaborative study.
BACKGROUND AND OBJECTIVES: In many countries, whole blood (WB) donations with collection times between 12 and 15 min are not allowed to be used for platelet concentrates (PC). Since the development of guidelines, many process-related changes have been introduced. We aimed to determine the effect of WB with long collection times on PC quality. MATERIALS AND METHODS: Five participating centres tested buffy coat (BC)-derived PC in platelet additive solution type E prepared from only WB collections lasting 12 min (study group, n = 8). One centre produced platelet-rich plasma (PRP)-derived PC from single donations (12 min). All PC were stored at 22 ± 2°C and sampled on Days 1, 6 and 8 post-collection for in vitro quality determination. RESULTS: Average collection time was significantly longer in the study group compared to controls (8.9 ± 2.6 vs. 7.3 ± 1.3 min, p 12 min had equivalent in vitro quality to controls during storage. This study provides evidence that 12-15 min donations should not be excluded for PC preparation and justifies to readdress the guidelines to <15 min instead of <12 min of collection in line with current practice in some countries
Main Properties of the THERAFLEX MB-Plasma System for Pathogen Reduction
Methylene blue (MB) treated plasma has been in clinical use for 18 years. The current THERAFLEX MB-Plasma has a number of improved features compared with the original Springe methodology. This overview embodies: the biochemical characteristics of MB, the mechanism of the technology, toxicology, pathogen reduction capacity, current position in clinical setting and status within Europe. The THERAFLEX MB (TMB) procedure is a robust, well standardised system lending itself to transfusion setting and meets the current guidelines. The pathogen kill power of the TMB system, like the other available technologies, is not limitless, probably in order of 6 log for most enveloped viruses and considerably less for non-enveloped ones. It does not induce either new antigen or grossly reducing the function and life span of active principle in fresh frozen plasma (FFP). The removal of the residual MB at the end of the process has the beneficial effect of reducing potential toxic impacts. Clinical haemovigilance data, so far, indicate that cell-free MB plasma is effective in all therapeutic setting requiring FFP, besides inconsistent thrombotic thrombocytopenia purpura data, without serious side-effects or toxicity. The current system is in continuous improvement e.g. regarding virus reduction range, illumination device, software used, and process integration in the blood bank setting
UVC Irradiation for Pathogen Reduction of Platelet Concentrates and Plasma
Besides the current efforts devoted to microbial risk reduction, pathogen inactivation technologies promise reduction of the residual risk of known and emerging infectious agents. A novel pathogen reduction process for platelets, the THERAFLEX UV-Platelets system, has been developed and is under clinical evaluation for its efficacy and safety. In addition, proof of principle has been shown for UVC treatment of plasma units. The pathogen reduction process is based on application of UVC light of a specific wavelength (254 nm) combined with intense agitation of the blood units to ensure a uniform treatment of all blood compartments. Due to the different absorption characteristics of nucleic acids and proteins, UVC irradiation mainly affects the nucleic acid of pathogens and leukocytes while proteins are largely preserved. UVC treatment significantly reduces the infectivity of platelet units contaminated by disease-causing viruses and bacteria. In addition, it inactivates residual white blood cells in the blood components while preserving platelet function and coagulation factors. Since no photoactive compound needs to be added to the blood units, photoreagent-related adverse events are excluded. Because of its simple and rapid procedure without the need to change the established blood component preparation procedures, UVC-based pathogen inactivation could easily be implemented in existing blood banking procedures