The role of in process qualification in quality improvement of the haemonetics MCS plus leucodepleted platelet concentrate

With the implementation of universal leucodepletion in UK all leucodepletio n processes have gone through a standard process qualification and quality improvement. The Haemonetics MCS system is a well established automated pla telet collection system for the production of double dose leucoreduced plat elet concentrate (WBC congruent to 70 x 10(6)/dose). Recently an automated post collection filtration harness system has been introduced (MCS plus LDP ) in which platelets are filtered, using an in-line PALL polyester filter ( LRFH6 PALL) to reduce the WBC level to below 5 x 10(6) WBC/ dose. This syst em passed our Phase I evaluation process based on 20-40 runs. However, some changes in the final volume of the products were needed to conform to nati onal guidelines. Large scale trials using the new volume adjusted protocol revealed occasional failure in the leucocyte content. Therefore, 100% testi ng had to be implemented on all products. A national evaluation was carried out to determine whether changing the filter to a more efficacious one, th e LRFXL (PALL) or slowing the filtration flow rate can influence the overal l outcome. To reduce donor variability, known donor population were used wi th identical apheresis conditions. A more consistent and systematic drop in leucocyte content was observed by reducing the flow rate whereas a similar failure (i.e. 1-3%) rate was found both in controls and LRFXL when using t he standard head pressure, which is recommended by the manufacturer. A simi lar failure rate was found using three different low leucocyte counting tec hnologies (Nageotte, flow cytometry and Imagn 2000). It is recommended that a process qualification/validation program should be implemented when even a small modification in the collection system is introduced. (C) 2000 Else vier Science Ltd. All rights reserved.