Cellular contamination of plasma collected with various apheresis systems

Efforts to improve the purity of blood products have mainly focused on reducing white blood cell (WBC) levels in cellular blood products. Relatively little attention has been given to the cellular purity of plasma. We evaluated plasma units collected on six apheresis systems: Dideco Excel, Haemonetics-MCS+, Fresenius-AS-Tech 204, Baxter-Amicus, Gambro BCT COBE Spectra and Gambro BCT-Trima. Collected plasma volumes averaged 300-350 ml for the various systems. Plasma samples were analyzed for platelet (PLT) content (Technicon H3, Bayer) and residual WBC (Imagn 2000). Results are given below. Platelet levels were consistently low for MCS+, COBE Spectra and Trima (all <50 x 10(3) microl(-1)), and were highest with AS204. Residual WBC levels were relatively low in all systems except MCS+. Extremely low levels were observed in Trima plasma. All of the Trima and Spectra units contained <1 x 10(6) WBC per product. With Excel, AS-Tech 204 and Amicus, 1 to 2 units were found to have >1 x 10(6) WBC, while almost all units from MCS+ exceeded this limit. Different levels of plasma purity were obtained with different apheresis systems. The Gambro BCT COBE Spectra and Trima systems were found to achieve consistently low levels of both platelets and WBC.