Detection of HTLV-I and -II in Scottish blood donor samples and archive donations.
OBJECTIVE
Positive samples identified during routine serological screening for HCV (hepatitis C virus), HBV (hepatitis B virus) and HIV (human immunodeficiency virus) are confirmed by nucleic acid testing in the SNBTS (Scottish National Blood Transfusion Service) PCR Reference laboratory. Serological screening for HTLV-I (human T-cell lymphotropic virus type I) and -II was implemented in Scotland in November 2002, at which time a PCR assay was not available for confirmation. Our aim was to develop a real-time PCR assay that could be used for the confirmation of samples showing HTLV-I serological positive or indeterminate reactivity and to investigate whether a serologically silent carrier status exists ('Tax' only) in the Scottish donor population.


METHODS
A real-time HTLV PCR was devised using a lymphoblastoid cell line which has HTLV-I sequence integrated in the genome (C8166 cells). These were spiked into peripheral blood mononuclear cells. The assay was evaluated on archived serologically confirmed HTLV-positive samples and new positives identified since implementation of screening.


RESULTS
HTLV-I and -II were detected in cells and plasma from stored donations and a serological positive donation identified in routine screening. HTLV DNA can also be amplified from the plasma obtained from plasma preparation tubes. There was no evidence of a carrier status ('Tax' only) in 100 serologically negative blood donors tested. The PCR assay developed is reliable and sensitive, capable of identifying one copy of HTLV-I.


CONCLUSIONS
The HTLV PCR is a useful addition for HTLV confirmation, especially in serologically indeterminate samples and for look-back studies. HTLV PCR confirmation will provide additional useful information for donor medical staff for counselling donors.
Davidson
F
F
Transfusion Transmitted Infection Group, Scottish National Blood Transfusion Service, Royal (Dick) Veterinary College, Summerhall, Edinburgh, UK. fiona.davidson@snbts.csa.scot.nhs.uk
Lycett
C
C
Jarvis
L M
LM
Kerr
D
D
Lumley
S
S
Petrik
J
J
Dow
B C
BC
D001782:Blood Donors; D001803:Blood Transfusion; D016355:Genes, pX / Q000235:genetics; D015490:HTLV-I Infections / Q000175:diagnosis; D015491:HTLV-II Infections / Q000175:diagnosis; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000276:immunology; D015367:Human T-lymphotropic virus 2 / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008403:Mass Screening / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods*; D012606:Scotland; D012698:Serologic Tests / Q000379:methods