BACKGROUND: Epstein-Barr virus (EBV) infection results in life-long carriage of latent virus in B lymphocytes in the majority of the adult population, including blood donors. The removal of EBV from red blood cell (RBC) components by leukoreduction was assessed. STUDY DESIGN AND METHODS: Sixteen randomly selected fresh AS-5 units were leukoreduced by filtration. B lymphocytes from preleukoreduction specimens and mononuclear cells (MNCs) from postleukoreduction specimens were assayed for EBV DNA with sensitive real-time polymerase chain reaction (PCR). RESULTS: EBV genomes were detected in CD19 + B cells in 14 of 16 preleukoreduced RBC units. EBV genomic copy number in the units ranged from 0.18 to 96.84 per 10 5 B lymphocytes representing approximately 135 to 72,630 total EBV genomes per bag. Leukoreduction rendered all but one unit EBV-negative by PCR. The lone PCR-positive unit after leukoreduction amplified 1.2 EBV genome copies from MNCs recovered from the entire unit of leukoreduced RBCs; this unit had the highest EBV viral load before leukoreduction (72,630 EBV genomes). CONCLUSIONS: These results indicate that a 4-log reduction of EBV genomic copy number can be achieved with leukoreduction of RBC units and renders most RBC units EBV-negative by sensitive PCR. pstein-Barr virus (EBV) infects and establishes life-long latency in B lymphocytes of the majority of adult population. 1,2 EBV is the causative agent of infectious mononucleosis (IM). It has also been implicated in the etiology of malignancies such as Burkitt's lymphoma and lymphoproliferative diseases in the immunocompromised host, including posttransplant lymphoproliferative disorders and AIDS-related lymphomas. 1,2 In immunocompetent healthy individuals, EBV genomes can be detected in circulating peripheral blood B cells by polymerase chain reaction (PCR). 3,4 The frequency of EBV infected circulating B cells is estimated to be 1 in 10 5 to 1 in 10 6 . 5-7 Transfusion-transmitted EBV from cellular blood components has been infrequently reported. [8][9][10][11][12][13] Leukoreduction with third-generation filters depletes greater than 3 logs (99.9%) of white cells (WBCs) from blood components. This process has been shown to reduce the number of cytomegalovirus (CMV) genomes and its infectivity in cellular blood component. 14,15 Similar studies have not been performed on EBV. We evaluated the efficacy of EBV-infected B-cell removal with sensitive PCR testing of pre-and postleukoreduced red blood cell (RBC) components.
MATERIALS AND METHODS
RBC component processing and filtrationSixteen fresh AS-5 RBC units were randomly selected from the regional FDA-licensed blood center (Central Blood Bank, Pittsburgh, PA) from donations in January 2004. Leukoreduction was performed in the laboratory via sterile docking of a leukoreduction filter (Sepacell R-500 II, Baxter, Deerfield, IL) according to manufacturer's instructions. Filtrations and lymphocyte preparations were performed within 48 to 72 hours of blood collection. Pre-and postleukoreduction specimens w...