Evaluation of HTLV-I removal by filtration of blood cell components in a routine setting.
BACKGROUND
WBC depletion by filtration may prevent the transmission of HTLV-I, which requires cell-to-cell contact. The removal of HTLV-I-infected cells in routinely filtered blood cell components was measured.


METHODS
The study was conducted in Martinique where systematic screening for HTLV-I and -II and universal leukoreduction are mandatory. HTLV-I was quantified by use of real-time PCR in 8 RBC units and 4 PLT concentrates before and after filtration. HTLV-I proviral load in PBMNCs was determined in five of the eight HTLV-I-infected blood donors.


RESULTS
The amount of MNC-associated HTLV-I DNA in RBC units before filtration was 21 x 10(6)+/- 29 x 10(6) copies (mean +/- SD). HTLV-I was detected in 4 of 8 RBC units after filtration, with a number of copies in the MNC fraction ranging from 20 to 140, following a 4.9 to 5.8 log reduction. Flow cytometry analysis performed in 2 of the filtered RBC units containing detectable HTLV-I showed suboptimal and out-of-range leukoreduction (0.56 x 10(6) and 1.22 x 10(6) residual WBCs). HTLV was not detected in filtered RBCs from the blood donor with the highest percentage of HTLV-I-infected PBMCs (9%).


CONCLUSIONS
This study confirms that HTLV-I-infected cells can be detected in filtered blood cell components and shows that optimal leukoreduction is critical for HTLV-I removal.
Césaire
Raymond
R
Laboratory of Virology and Immunology and Hemovigilance Unit, University Hospital Center of Fort-de-France, Martinique. raymond.cesaire@chu-fortdefrance.fr
Kérob-Bauchet
Brigitte
B
Bourdonné
Olivier
O
Maier
Hélène
H
Amar
Karim Ould
KO
Halbout
Philippe
P
Dehée
Axelle
A
Désiré
Nathalie
N
Dantin
Fabienne
F
Béra
Odile
O
Lézin
Agnès
A
D001773:Blood Cells / Q000821:virology*; D001782:Blood Donors; D001792:Blood Platelets / Q000821:virology; D003199:Computer Systems; D004279:DNA, Viral / Q000032:analysis; D006800:Deltaretrovirus Infections / Q000097:blood / Q000821:virology*; D004912:Erythrocytes / Q000821:virology; D005374:Filtration; D005434:Flow Cytometry; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007937:Leukapheresis; D009000:Monocytes / Q000821:virology; D016133:Polymerase Chain Reaction; D011786:Quality Control; D012680:Sensitivity and Specificity; D019562:Viral Load
D004279:DNA, Viral