Effects of storage and leukoreduction on lymphocytes and Epstein-Barr virus genomes in platelet concentrates.
BACKGROUND
Epstein-Barr virus (EBV) persists in infected B lymphocytes in blood donors. Lymphocytes are viable during platelet (PLT) storage. The effects of storage and leukoreduction on lymphocytes and EBV genomes are evaluated.


METHODS
Forty nonleukoreduced PLT concentrates were stored at 20 to 24°C for up to 7 days. EBV genomes in B cells were quantified on Days 1 and 5. Viable white blood cells (WBCs) and T and B cells were quantified in 10 of 40 units on Days 1, 3, 5, and 7 of storage. For the leukoreduction study, four pools of PLTs were leukoreduced within 24 hours of collection. B cells from before leukoreduction and all peripheral blood mononuclear cells from after leukoreduction were assayed for EBV.


RESULTS
Viable WBCs and T cells were stable whereas viable B cells were reduced to 71% of the Day 1 level by Day 5. A total of 31 of 37 (83.8%) units were EBV positive. Although EBV genomes remained stable in most units, 12 of 37 units demonstrated a median of 5.1 (range 2- to 134)-fold increase in EBV genomes per 105 B cells on Day 5. For the leukoreduction study, EBV genomes were detected in four of four pools before leukoreduction with a median of 3.8 (range, 0.2-93.6) EBV genomes per 105 B cells. EBV genomes were not detected in any of the postleukoreduction specimens.


CONCLUSIONS
Seventy percent of B lymphocytes are viable on Day 5 of PLT storage. Although the mean number of EBV genomes remained stable, a subset of units had increased EBV genomes during storage. Leukoreduction removed polymerase chain reaction-detectable EBV genomes from PLT pools.
Institute for Transfusion Medicine, 3636 Boulevard of the Allies, Pittsburgh, PA 15213, USA. qul@upmc.edu
Lirong
L
Qu
David T
DT
Rowe
Albert D
AD
Donnenberg
Deborah L
DL
Griffin
Darrell J
DJ
Triulzi
D001402:B-Lymphocytes / Q000166:cytology / Q000821:virology*; D001792:Blood Platelets / Q000166:cytology / Q000821:virology*; D002470:Cell Survival; D005260:Female; D016679:Genome, Viral; D004854:Herpesvirus 4, Human; D006801:Humans; D008297:Male; D010983:Plateletpheresis; D011309:Preservation, Biological; D013601:T-Lymphocytes / Q000166:cytology