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PROGRAMME AND ABSTRACT BOOK
ABS TRAC T BOOK
nopositivity. With this panel of validated antibodies, we plan
to study the nature of myocardial atrio-ventricular continuity
and development of annulus fibrosus in the crocodilian heart.
We would like to thank the Protivin ZOO (Ing. Prochazka)
for permission to collect the damaged Crocodylus siamensis
eggs. This study was supported by MSMT PRVOUK-P35/LF1/5.
7) Immune cell populations in human atrial
myocardium from patients with atrial fibrillation
Kučera T.
1
, Smorodinova N.
1
, Cohen-Addad D.
1
,
Chen Ben-David
1
, Přidal J.
1
, Ďurišová M.
1
, Pirk J.
3
,
Bláha M.
2
, Melenovský V.
2
, Kautzner J.
2
1
Institute of Histology and Embryology, The First Faculty
of Medicine, Charles University in Prague
2
Institute for Clinical and Experimental Medicine-IKEM,
Department of Cardiology, Prague
3
Institute for Clinical and Experimental Medicine-IKEM,
Department of Cardiovascular Surgery, Prague
Introduction:
The processes underlying the initiation and
development of atrial fibrillation (AF) are still not sufficiently ex-
plored. One of the generally recognized factors contributing to
persistency of AF is structural remodeling of the myocardium.
There is alteration in both cardiomyocyte morphology as well
as changes affecting endomysium. It is hypothesized that some
of these changes are caused by an inflammatory processes.
Aim:
In this study we focused on morphological and func-
tional changes in endomysium of atrial myocardium with
special attention to CD45+- cells, representing cells of bone
marrow origin. In addition, we characterize different types of
resident or infiltrating immune cells.
Methods:
We analyzed atrial biopsies obtained from pati-
ents undergoing bypass or mitral valve surgery. The patients
had a regular sinus rhythm or were suffering from AF. The atrial
samples were fixed with 4 % paraformaldehyde and embedded
into paraffin. Sections from atrium were histologically exami-
ned using routine hematoxylin-eosin staining. For detection
of different types of immune cells the following markers were
detected immunohistochemically: CD45 as a pan-leukocyte
marker, CD3 for T-lymphocytes, CD68 for monocyte/macro-
phages, mast cell tryptase for mast cells and DC-SIGN for imma-
ture dendritic cells. Three-step immunoperoxidase detection
was performed on paraffin sections after antigen retrieval and
images were taken using Leica DMLB microscope equipped
with DC300 camera. For double labeling we used immunoflu-
orescence approach and images were taken using a confocal
laser scanning microscope (FV1000, Olympus)
Results:
In all atrial samples from both groups we detected
CD45+-cells in atrial myocardium as well as in endocardium
and epicardium. The frequency of these cells was variable. Atria
from patients with atrial fibrillation had tendency for a higher
infiltration with CD45+ cells. Apparently, CD45+ cells formed
a heterogeneous group of cells. We also detected CD68+cells,
CD3+cells, mast cells and DC-SIGN-positive dendritic cells. A du-
al immunostaining showed CD45+/CD3+, CD45+/CD68+ and
CD68+/DC-SIGN double positive cells. There were CD45+ and
CD68+ cells with elongated shape sending out long cellular
processes, these corresponded mainly to DC-SIGN-positive
dendritic cells. We performed a semiquantitative analysis of
CD45+ cells with elongated cell bodies and found that they
are more frequent in auricular samples from patients with atrial
fibrillation. The difference reached statistical significance in the
right atrial samples.
Conclusion:
Our results document that CD45+ cells are
a heterogeneous cell population in atrial myocardium from
patients undergoing open heart surgery and these cells can be
detected regardless of the heart rhythm. The finding of higher
frequency of CD45+ leukocytes with elongated processes in
the AF samples suggests the activation of inflammatory cells
in this arrhythmia. It has to be confirmed whether all these cells
are immature dendritic cells or they represent more diverse
population.
This work was supported by the Research Program of Charles
University – PRVOUK -P25/LF1/2.
8) Methylace tumor supresorových genů
u hepatocelulárního karcinomu
Mžik M.
1,2
, Chmelařová M.
1
, Laco J.
3
, Radová L.
4
,
Palička V.
1,2
, Nekvintová J.
1,4
1
Ústav klinické biochemie a diagnostiky,
Fakultní nemocnice Hradec Králové
2
Univerzita Karlova v Praze, Lékařská fakulta
v Hradci Králové
3
Fingerlandův ústav patologie Lékařské fakulty Univezity
Karlovy a Fakultní nemocnice v Hradci Králové
4
Ústav molekulární a translační medicíny, Lékařská
fakulta Univerzity Palackého v Olomouci
Hepatocelulární karcinom (HCC) patří mezi méně častá ná-
dorová onemocnění, avšak představuje 90 % všech primárních
jaterních malignit. V Evropě dosahuje incidence 2 až 11 případů
na 100 000 obyvatel. Onkogeneze HCC je důsledkem souboru
biologických a genetických poškození buňky, kde se uplatňuje
kombinace defektu tumor supresorových genů a aktivace on-
kogenů s významným podílem epigenetických mechanizmů.
U HCC dochází ke změnám v methylaci širšího spektra genů
i ke změně profilu mikroRNA. V této studii byly porovnávány
rozdíly v methylaci promotorů tumor supresorových genů
ve vzorcích hepatocelulárního karcinomu a okolní nenádorové
tkáně. Pomocí methylačně specifické MLPA (multiple ligation
probe assay) bylo identifikováno pět diferenciálně methylova-
ných tumor supresorových genů při cut-off methylace 20 %
a hladině významnosti 0,05 (Wilcoxonův test) – PAX5, PAX6,
WT1, GSTP1 a PYCARD. Výsledky byly konzistentní na více hla-
dinách cut-off i přímém porovnání naměřených hodnot, a to
jak v párovém, tak nepárovém srovnání. Methylace promotorů
genů PAX6 (paired box gene 6, genový regulátor exprimovaný
zejména ve vyvíjející se nervové a oční tkáni), WT1 (Wilms
