Læknablaðið : fylgirit - 03.01.2017, Blaðsíða 80

X V I I I V Í S I N D A R Á Ð S T E F N A H Í
F Y L G I R I T 9 1
80 LÆKNAblaðið/Fylgirit 91 2017/103
Introduction: We previously showed that when dendritic cells (DCs)
were matured in the presence of exopolysaccharides from Cyanobacter-
ium aponinum (EPS-Ca), one of the main organisms in the Blue Lagoon,
they secreted more of IL-10 than control DCs. Furthermore, DCs matured
in the presence of the EPS-Ca led to less activation and differentiation of
ROR-γt+IL-17+ T cells. In the present study, the effects of the EPS-Ca on
keratinocytes stimulation was determined.
Materials and methods: HaCaT cells (immortalized keratinocytes) were
incubated with EPS-Ca and then stimulated with TNF-α and either IFN-
-γ or IL-17 to mimic Th1 or Th17 cytokine environment, respectively.
The concentration of cytokines and chemokines in supernatants from
the HaCaT cellswas determined by ELISA and surface molecule ex-
pressionwas determined by flow cytometry.
Results: When the HaCaT cells were stimulated with IFN-y and TNF-
-α, EPS-Ca increased their secretion of IL-6, IL-8, CCL3 and CCL20 but
decreased their secretion of CXCL10. When they were stimulated with
IL-17 and TNF-α, EPS-Ca increased their IL-6 and CCL3 secretion. EPS-
-Ca increased the expression of ICAM-1 on HaCaT cells stimulated with
IL-17 and TNF-α and increasedCD29 (β1 integrin) expression on HaCaT
cells stimulated with IFN-y and TNF-α. EPS-Ca did not affect surface
expression of E-cadherin, HLA-I, HLA-DR, CD44, CD247 (PD-L1) and
CD183 (CXCR3) on HaCaT cells.
Conclusions: Although the effects of EPS-Ca on DCs led to a decrease in
their induction of a Th17 response, their effects on keratinocytes seem to
be pro-inflammatory when stimulated in Th1 environment but to a lesser
extent when stimulated in a Th17 environment.
V 61 Makrólíða ónæmir streptókokkar af flokki A á Íslandi
Sara B. Southon1,2,3, Gunnsteinn Haraldsson2,3, Priyanka Kachroo4, Stephen B.
Beres4, Helga Erlendsdóttir2, Karl G. Kristinsson2, James M. Musser4
1Sýklafræðideild Landspítala, 2læknadeild, 3Lífvísindasetri Háskóla Íslands, 4Houston
Methodist Research Institute
sbs45@hi.is
Inngangur: Streptococcus pyogenes (group A Streptococcus, GAS) er mikil-
vægur sýkingavaldur í mönnum og alvarlegar sýkingar af völdum bakt-
eríunnar hafa háa dánartíðni. Makrólíðaónæmi er vaxandi áhyggjuefni
þegar kemur að meðferð GAS sýkinga. Markmið rannsóknarinnar var að
kanna hvað veldur makrólíðaónæmi í GAS á Íslandi.
Efniviður og aðferðir: Erythromycin ónæmir GAS sem höfðu verið
greindir og geymdir á Sýklafræðideild LSH á árunum 1998-2015 voru
sendir til Houston Methodist Research Institute (Houston, Texas), þar sem
þeir voru heilraðgreindir í Illumina NextSeq tæki. Genatjáning mefA-msrD
var rannsökuð hjá 15 fulltrúum hverrar emm-týpu, með qRT-PCR, 5 stofn-
ar fyrir hverja emm-týpu. Genatjáning mefA-msrD eftir að stofnarnir voru
útsettir fyrir erythromycin var skoðuð í 4 stofnum.
Niðurstöður: Af 1532 stofnum, leiddi heilraðgreiningin í ljós að 1364
(89,0%) stofnanna voru af emm-týpum M4 (n=704), M6 (n=330), og M12
(n=331). Af þessum 3 emm-týpum báru 1347 (98,8%) makrólíða ónæmis
genin, mefA og msrD. Stofnar hverrar emm-týpu voru mjög skyldir inn-
byrðis. Raðir fyrir mefA-msrD og stýrill ofanvert við mefA-msrD voru nán-
ast óbreyttar meðal GAS stofnanna. Tjáning mefA-msrD var svipuð meðal
M4 og M6 stofna en M12 stofnar sýndu tölfræðilega marktækt hærri tján-
ingu á mefA-msrD en M4 og M6 stofnarnir. Allir 4 stofnar sem prófaðir
voru sýndu hærri tjáningu á mefA-msrD eftir að stofnarnir voru útsettir
fyrir erythromycini.
Ályktanir: GAS stofnarnir voru mjög erfðafræðilega skyldir. Þrátt fyrir
þennan skyldleika sýna stofnar af emm-týpu M12 hærri tjáningu á mefA-
-msrD en stofnar af öðrum emm-týpum. Útsetning fyrir erythromycini örv-
ar tjáningu á mefA-msrD genagenginu.
V 62 Elucidation of different cold-adapted Atlantic cod (Gadus
morhua) trypsin X isoenzymes
Gunnar Sandholt1, Bjarki Stefánsson1, Ágústa Guðmundsdóttir2
1Zymetech, 2matvælafræðideild, Zymetech
gbs1@hi.is
Introduction: Trypsins from Atlantic cod (Gadus morhua), consisting of
several isoenzymes, are highly active cold-adapted serine proteases. These
trypsins are isolated for biomedical use in an eco-friendly manner from
underutilized seafood by-products. For broader utilization of cod tryps-
ins, further characterization of biochemical properties of the individual
cod trypsin isoenzymes is of importance. For that purpose, a cod trypsin
X isoenzyme variant CTX-V7 from a benzamidine purified Atlantic cod
trypsin isolate was analyzed.
Materials and Methods: Benzamidine purified cod trypsin, anion
exchange chromatography, mass spectrometry, enzyme activity assay,
stability measurements (pH, temperature), inhibition studies and kinetic
analysis.
Results: Anion exchange chromatography revealed eight peaks contain-
ing proteins with tryptic activity and in the size range of 24 kDa. Based on
mass spectrometric analysis, one isoenzyme gave the best match to cod
trypsin I and six isoenzymes gave the best match to cod trypsin X. One
trypsin X isoenzyme, CTX-V7, was selected for further characterization
based on abundance and stability.
Discussion: The study demonstrates that the catalytic efficiency of CTX-
-V7 is comparable to that of cod trypsin I, the most abundant and hig-
hly active isoenzyme in the benzamidine cod trypsin isolate. Differences
in pH stability and sensitivity to inhibitors of CTX-V7 compared to cod
trypsin I were detected that may be important for practical use.
V 63 N,N,N-trimethyl chitosan as an efficient antibacterial agent for
polypropylene and polylactide nonwovens
Priyanka Sahariah1, Dawid Stawski2, Martha Á. Hjálmarsdóttir3, Dorota
Wojciechowska2, Michal Puchalski4, Már Másson3
1Pharmaceutical Sciences, University of Iceland, 2Lodz University of Technology, 3University of
Iceland, Lodz University of Technology
prs1@hi.is
Introduction: The most important biomedical characteristics of fibrous
materials in the area of medicine and hygiene are their antimicrobial
properties. Such properties can be obtained by treatment of textiles with
compounds possessing antimicrobial activity, such as the N,N,N-tri-
methylchitosan (TMC) which possesses high antimicrobial properties.
Methods: TMC was selected as the antibacterial agent for modification
of polypropylene (PP) and polylactide (PLA) nonwovens. In this study,
two step modification of the nonwoven’s surface was applied. The first
phase was to create a negatively charged surface on the fibres and second
phase was to layer by layer assemble the TMC through electrostatic inter-
action. Gravimetric measurement, scanning electron microscopy, energy
dispersive spectroscopy and reflectance Fourier transform infrared spect-
roscopy were utilized to characterize the morphology and composition of
the modified fibres.
Results: The results show that TMC can be used as a polyelectrolyte layer