Abstracts (complete list) - Wissenschaft Online

Anastasia Schneider, Tatiana Binder, Rodica Bernatowicz, Anke Zobywalski, Christine
Falk, Anton Hartmann, Dolores Schendel, Susanne Krauss-Etschmann
MODULATION OF HUMAN DENDRITIC CELLS BY SIX
DIFFERENT PROBIOTIC BACTERIAL STRAINS
Background
Lactobacilli (Lb) and bifidobacteria (Bb) are probiotic bacteria and have been suggested
to protect against allergic diseases. Since the underlying immune mechanisms are
unclear at present, we tested whether six different probiotic strains polarize the
maturation of human monocyte-derived dendritic cells (moDC).
Methods
UV-inactivated and live Lb rhamnosus GG (LGG, Valio Ltd, Finland), Bf. species 420
(Bifidobacterium lactis, Danisco Deutschland GmbH), Lb acidophilus LA-5, Lb paracasei
subsp. paracasei LC-01, Bb animalis BB-12 and Bb longum BB-46 (Chr.Hansen GmbH,
Denmark) or LPS were co-cultured with moDC at ratios of 1-100 bacteria per one DC for
24 h. UV-inactivated bacteria were counted visually after DAPI-staining. Viability of live
bacteria was more than 90% as evaluated with a live/dead-staining kit (Invitrogen
GmbH). Surface expression of costimulatory molecules on DC was analyzed by flow
cytometry. Cytokines (IL-1beta, -6, -10, -12, TNF-alpha, IFN-gamma) and chemokines
(IL-8, MIP-1alpha, MIP-1beta) were quantified in culture supernatants by multiplex
assay (Bio-Rad Laboratories GmbH). Results are expressed as percentage of LPS
stimulation.
Results
Priming with UV-inactivated BB-12 induced the highest synthesis of IL-6, -8, -10, -12,
TNF-alpha and MIP-1alpha by moDC, while UV-inactivated LA-5 induced the highest
synthesis of IL-1beta, IFN-gamma and MIP-1beta. In preliminary experiments, UVinactivated
or live probiotics induced similar expression of costimulatory molecules on
moDC.
Conclusions
The response of human moDC to UV-inactivated probiotics depends on the bacterial
strain. UV-inactivated and live probiotics lead to similar expression profiles of
costimulatory molecules on moDC. The analysis of the cytokine production of DC will
show, whether this extends to soluble signals.