Journal of Clinical Virology - Volume 82 - Supplement 1 - September 2016

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Abstracts / Journal of Clinical Virology 82S (2016) S1–S142 S101
Abstract no: 333
Presentation at ESCV 2016: Poster 161
Monitoring of cytomegalovirus-specific
immunity using the QuantiFERON-CMV assay in
hematopoietic cell transplant recipients:
Preliminary results
Joana Ribeiro ∗, C. Pinho Vaz , F. Campilho ,
R. Branca , A. Campos Jr , I. Baldaque ,
H. Sousa
1 Molecular Oncology & Viral Pathology Group,
IPO-Porto Research Center (CI-IPOP), Portuguese
Oncology Institute of Porto (IPO-Porto), Portugal
2 Bone Marrow Transplantation Unit, Portuguese
Institute of Oncology of Porto, Portugal
3 Virology Service, Portuguese Oncology Institute of
Porto (IPO-Porto), Portugal
Introduction: Human Cytomegalovirus (CMV)-associated com-
plications are often associated with high morbidity and mortality
in patients submitted to allogeneic hematopoietic stem cell
transplant (allo-HSCT) despite the improvement in the clinical
management of CMV infection either by viral monitoring or antivi-
ral prophylaxis. The reconstitution of antiviral cellular immunity
after allo-HSCT is crucial for the prevention of viral reactiva-
tions/infections and associated complications. In fact, antiviral
cell-mediated immunity specific to CMV is considered crucial for
the control of CMV replication, and therefore, monitoring the inter-
feron (IFN- ) produced by CMV-specific T-cells may be useful as
a prognostic marker of CMV infection.
Aim: The aim of this study was to evaluate the levels of CMV-
specific IFN- produced by CD4+ and CD8+ T-cells in patients
submitted to allo-HSCT and evaluate its utility in clinical manage-
ment of CMV.
Material and methods: We have selected five consecutive allo-
HSCT recipients considered of high risk for CMV infection. All
patients received stem cells from a HLA mismatched/unrelated
and CMV IgG seropositive positive donor; 4 patients were CMV-
seropositive (R+) and 1 CMV-seronegative (R−). All patients were
monitored for CMV infection using pp65 antigenemia or quantita-
tive real-time PCR. Themonitoring of IFN- levels produced by CMV
specific T-cells were evaluated weekly from day 60 post-transplant
in 3 consecutive evaluations using QuantiFERON-CMV® assay.
Results: The QuantiFERON-CMV assay revealed that 3 patients
had cellular immunity to CMV and 2 had no detectable immune
response (IFN- levels <0.2 cut-off). During the follow-up period
two patients had CMV reactivation/viremia on the first 7 days of
follow-up (both D+/R+): one showed low levels (<1.0) and the
other was non-reactive for (<0.2) of CMV-specific IFN- . Of the 3
patients who had no CMV reactivation, 1 was non-reactive and
2 presented high levels of CMV-specific IFN- . Our preliminary
results showed that conditioning regimens might influence the
CMV-specific immune response: the 2 patients that underwent
reduced intensity regimen (RIC) were able to mount CMV-specific
immune response; while of the 3 patients submitted to myeloabla-
tive regimen (MA), 2 were non-reactive and 1 showed low levels of
CMV-specific IFN- becoming non-reactive at the 3rd evaluation.
Conclusion: These are a preliminary results from a prospec-
tive study involving allo-HSCT patients from Portugal. The results
revealed that patients with high levels of cellular immune response
to CMV seems to have a lower risk of developing CMV reactivation
than those who do not have a detectable immune response or
with low levels of CMV-specific IFN- . Our preliminary results also
showed that QuantiFERON-CMV test could be an important tool
in CMV monitoring after allo-HSCT. However a clinical cut-off for
QuantiFERON-CMV should be investigated to distinguish patients
with high or low risk for CMV-associated complications.
Abstract no: 336
Presentation at ESCV 2016: Poster 162
HHV-6 chromosomal integration in allogeneic
haematopoietic stem cell transplantation
Petr Hubacek ∗, Ales Briksi , Ivana Zelezna ,
Jana Sumova , Petra Chramostova ,
Petra Keslova niela Janeckova
Miroslav Zajac , Renata Formankova ,
Michal Kouba rketa Markova-Stastna
Veronika Valkova , Jan Vydra , Petr Cetkovsky ,
Petr Sedlacek
1 2nd Faculty of Medicine of Charles Univeristy and
Motol University Hospital, Prague, Czech Republic
2 Motol University Hospital, Prague, Czech Republic
3 Institute of Haematology and Blood Transfusion,
Prague, Czech Republic
Objectives: Chromosomal integration of HHV-6 is an interest-
ing biological phenomenon of distinct impact of Ci-HHV-6 carriers.
According to the published knowledge, Ci-HHV-6 genome is at least
partly transcribed with a pro-inflammatory impact documented
recently by increased risk of cardiac angina pectoris. The observed
frequency of Ci-HHV-6 in the population of the Czech Republic is
about 1%. Therefore we wanted to find out the frequency of Ci-
HHV-6 among the allogeneic haematopoietic stem cell transplant
(alloHSCT) recipients and its possible impact on the CMV infection.
Methods: Between January 2003 and June 2015, we tested for
presence of HHV-6 7857 samples from more than 37,000 whole
blood samples send for viral surveillance from 326 children and
652 adults after allogeneic HSCT. At least one sample was tested
pre- and one after HSCT after stem cell engraftment and recovery
of haematopoiesis was obtained in 839 donor/recipient combina-
tions and so we tested presence of HHV-6 both recipient and donor
haematopoiesis. DNAextractionwas performedusingQiagenBlood
Mini Kits according to the manufacturer’s instructions and testing
was performed subsequently using RQ-PCR technology for HHV-6,
same as for CMV and EBV in the samples. In the recipients, Ci-
HHV-6 was confirmed by detection in the nails. Additional samples
from the patients, such as tissue, nails and other biological samples
(BALs, urine, CSF, etc.), were extracted by appropriate DNA extrac-
tion kits and tested in the same way. Viral quantity in the sample
was normalised to 100,000 human genome equivalents assessed
by quantification of human albumin gene.
Results: HHV-6 DNA was detected in 979 (11.5%) samples from
94 children (28.8%) and 100 adult (15.3%) patients after the HSCT
in 46 children and 25 adults before HSCT. From these, Ci-HHV-6
was confirmed in 4 patients (in recipient) and 7 donors (2 more
are suspected) as in engrafted post-transplant blood cells by long
lasting high HHV-6 positivity and viral/human DNA ratio about 1:1.
In 7 patients with Ci-HHV-6, we detected HHV-6A; in the rest HHV-
6B was detected. Two patients carrying Ci-HHV-6 before alloHSCT
and 4 transplanted from Ci-HHV-6 positive donor died from post-
transplant complications having tissue samples tested as well.
In one patient, multiple viral infections were observed including
EBV-LPD from donor Ci-HHV-6 positive cells. Patient subsequently
deceased without any GvHD due to relapse of the primary
leukaemia.
In total, CMV was detected in 644 patients (65.8%) from the
cohort and virostatic treatment was started in 350 (35.8%) of them.