Effects of use of riboflavin and ultraviolet light for pathogen inactivation on quality of platelet concentrates

Abstract

Background/Aim. Pathogen inactivation in blood and blood products is one of the major means to achieve a zero risk blood supply and improve transfusion safety. Riboflavin (vitamin B2) activated by ultraviolet (UV) light, produces active oxygen which damages cell membrane and prevents replication of the carrier of diseases (viruses, bacteria, protozoa) in all blood products. The aim of this study was to establish the influence of the process of pathogens photoinactivation using riboflavin and UV rays on the biochemical and functional characteristics of platelet concentrates prepared from ?buffy coat?. Methods. The examination included 80 platelet concentrates prepared from ?buffy coat?, which was separated from whole blood donated by voluntary blood donors around 6 hours from the moment of collection. Concentrates were pooled, filtered and separated unton two groups: one consisted of 10 control units and the other of 10 examined units (pooled platelet concentrates). Examined units of the platelets were treated by riboflavin (35 mL) and UV rays (6.24 J/mL, 265-370 nm) on Mirasol aparature (Caridian BCT Biotechnologies, USA) in approximate duration of 6 min. A total of 35 mL of saline solution was added to the control units. The samples for examining were taken from the control and examined units initially (K0, I0), after the addition of saline (K1) and riboflavin (I1), after illumination (I2), first day of storage (K3, I3) and the fifth day of storage (K4, I4). The following parameters were measured: platelet count and platelet yield, residual erythrocyte and leukocyte count, pH, pO2, pCO2 and bacterial contamination. Results. All the measured parameters showed a statistically significant decrease comparing to K0 and I0; all the results of the first day of platelet storage showed statistically significant decrease comparing to K1 and I1, and all the results of the fifth day of platelet storage (K4, I4) showed a statistically significant decrease comparing to K1 and K3 and to I1 and I3. There was no the mentioned difference in the measured parameters between K4 and I4 (the end of storage - the fifth day). All the platelet units were sterile till the seventh day, when the investigation ended. Conclusion. Platelet concentrates inactivated by riboflavin and UV rays (Mirasol PRT sistem, Caridian BCT, USA) keep all the characteristics assessed by the Guide to the preparation, use and quality assurance of blood components (Council of Europe), during the whole storage period (five days). The obtained data were correlated with existing up to date literature and demonstrated that Mirasol treated platelets were safe and could be incorporated effectively in the routine blood bank and transfusion setting.Uvod/Cilj. Inaktivacija patogena u krvi i produktima od krvi predstavlja znacajan korak u cilju dobijanja bezbedne krvi, sto je jedan od prioriteta savremene transfuzioloske prakse. Riboflavin (vitamin B2) aktiviran ultravioletnim (UV) zracenjem stvara aktivni kiseonik koji ostecuje celijsku membranu i sprecava replikaciju uzrocnika bolesti (virusi, bakterije, protozoe) u krvnim komponentama. Cilj ovog rada bio je da se utvrdi uticaj procesa fotoinaktivacije patogena primenom riboflavina i UV zracenja na biohemijske i funkcionalne karakteristike trombocita dobijenih izdvajanjem iz ?buffy coat? (leukocitno-trombocitnog sloja). Metode. Ispitivanje je obuhvatilo 80 koncentrata trombocita izdvojenih iz ?buffy coat?, dobijenog separacijom cele krvi dobrovoljnih davalaca krvi unutar sest sati od njenog uzimanja. Koncentrati trombocita su pulirani, pulovi filtrirani, a zatim podeljeni na 10 kontrolnih (K) i 10 ispitivanih (I) jedinica (pulova trombocita). Ispitivane jedinice trombocita tretirane su riboflavinom (35 mL) i UV zracenjem (6,24 J/mL, 265-370 nm) na aparatu Mirasol (Caridian BCT Biotechnologies, USA) u prosecnom trajanju od sest minuta. Kontrolnoj jedinici trombocita dodato je 35 mL fizioloskog rastvora. Uzorci za ispitivanje uzeti su iz kontrolnih i ispitivanih jedinica trombocita inicijalno (K0 i I0), nakon dodavanja fizioloskog rastvora (K1), odnosno riboflavina (I1), nakon izlaganja UV zracenju (I2), prvog dana (K3 i I3) i petog dana skladistenja (K4 i I4). Iz uzoraka su odredjivani broj i prinos trombocita, koncentracija rezidualnih eritrocita i leukocita, pH, pO2, pCO2 i bakterioloska ispravnost. Rezultati. Sve vrednosti ispitivanih parametara bile su znacajno statisticki nize u odnosu na vrednosti parametara iz uzorka K0 i I0. Sve vrednosti parametara prvog dana skladistenja trombocita (uzorci K3 i I3) bile su znacajno statisticki nize u odnosu na vrednosti parametara nakon dodavanja fizioloskog rastvora, odnosno riboflavina (uzorci K1 i I1). Takodje, sve vrednosti analiziranih parametara petog dana skladistenja (uzorci K4 i I4) bile su znacajno statisticki nize u odnosu na vrednosti parametara iz uzoraka K1 i K3, odnosno I1 i I3. Poredjenjem svih analiziranih parametara petog dana ispitivanja (uzorci K4 i I4), nije nadjena statisticki znacajna razlika izmedju kontrolne i eksperimentalne grupe. Svi uzorci trombocita sacuvali su sterilnost do sedmog dana, koliko je pracena bakterioloska ispravnost. Zakljucak. Trombociti inaktivisani primenom riboflavina i UV zracenja (Mirasol PRT sistem, Caridian BCT, USA) zadrzavaju sve karakteristike odredjene Preporukama za pripremu, upotrebu i obezbedjenje kvaliteta komponenata krvi Saveta Evrope tokom celog perioda skladistenja (pet dana). Rezultati su dosledni podacima prethodnih in vivo i in vitro ispitivanja i potvrdjuju da se trombociti tretirani na ovaj nacin mogu bezbedno primeniti u rutinskoj transfuzioloskoj praksi.