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Local drug therapy of oral inflammatory diseases is complicated by the chemical and physical conditions of the oral cavity. Salivary flow and gingival sulcus fluid as well as the movements of the tongue are causing dilution effects and mechanical influences. This makes it difficult for topically applied drugs to adhere to the oral mucosa. Nanocarriers based on chemically synthesized polymers could facilitate this targeted drug transport (drug targeting) by improving adhesion and penetration and leading to the accumulation of the drug in the target tissue. Dendritic polyglycerol sulfate (dPGS) and its derivative - hyper branched polyglycerol-co-polycoprolactane sulfate (h(PG-co-PCL)S) - are polymers that could be used as such drug targeting systems. h(PG-co-PCL)S- NC exhibits ester bonds, that ensure better degradability than dPGS-NC by endogenous enzymes. The demonstrated anti-inflammatory potential, e.g. through L- and P-selectin inhibition, makes both nanocarriers attractive candidates for the therapy of oral inflammatory diseases. Both polymers were found to be biocompatible in previous studies in vitro and exhibited the ability to penetrate into the human skin. In the present work, the penetration behavior was evaluated for the first time on the oral mucosa with application times of maximum 5 min. It was shown that static adherence was possible after 30 sec and penetration into buccal and masticatory mucosa after 5 min. In masticatory mucosa, both nanocarriers accumulated in the stratum corneum and penetrated only in small amounts into deeper viable epithelial layers. Penetration beyond the basement membrane into the lamina propria was not observed. Under the selected conditions, dPGS- and h(PG-co-PCL)S-NC did not provoke the release of pro-inflammatory cytokines, which may indicate that no inflammatory response is induced after application of those nanocarriers. While no reduction of mitochondrial activity was detected with dPGS-NC in oral gingival epithelial cells at different concentrations, h(PG-co-PCL)S-NC showed slightly reduced mitochondrial activity after 24 h with the highest concentration (c = 50 ��g/ml). These experiments are the basis for further evaluation of these nanocarriers in oral epithelial tissues in vivo and in vitro., Die lokale medikament��se Therapie oraler Entz��ndungserkrankungen wird durch die chemischen, physischen und physikalischen Gegebenheiten der Mundh��hle erschwert. Speichelfluss und gingivales Sulkusfluid oder die Bewegung der Zunge verursachen Verd��nnungseffekte bzw. mechanische Einfl��sse. Dies erschwert das Anhaften topisch applizierter Medikamente auf der oralen Schleimhaut. Nanocarrier auf der Basis chemisch synthetisierter Polymere k��nnten diesen gezielten Medikamententransport (Drug-Targeting) durch Verbesserung von Adh��sion und Penetration erleichtern und zu einer Wirkstoffanreicherung im Zielgewebe f��hren. Dendritisches Polyglycerolsulfat (dPGS) und dessen Derivat - hochverzweigtes Polyglycerol-co-Polycoprolactan-Sulfat (h(PG-co-PCL)S) - sind Polymere, die als solche Drug-Targeting-Systeme genutzt werden k��nnten. h(PG-co-PCL)S weist Esterbindungen auf, welche eine bessere Abbaubarkeit als dPGS durch k��rpereigene Enzyme garantieren. Das nachgewiesene anti-inflammatorische Potential, z.B. durch eine L- und P-Selektin-Hemmung, macht beide Nanaocarrier zu attraktiven Kandidaten f��r die Therapie oraler Entz��ndungserkrankungen. Beide Polymere wurden in vorangegangenen Studien in vitro als biokompatibel eingestuft und zeigten die F��higkeit, in humane Haut zu penetrieren. In der vorliegenden Arbeit wurde das Penetrationsverhalten erstmals auf der oralen Mukosa mit Applikationszeiten von maximal 5 min evaluiert. Es konnte gezeigt werden, dass nach bereits 30 s eine statische Adh��renz und nach 5 min auch eine Penetration in bukkale und mastikatorische Mukosa m��glich war. In mastikatorischer Mukosa akkumulierten beide Nanocarrier im Stratum corneum und penetrierten nur in geringen Mengen in tiefere viable Epithelschichten. Eine Penetration ��ber die Basalmembran in die Lamina propria hinaus konnte nicht beobachtet werden. dPGS und h(PG-co-PCL)S provozierten unter den gew��hlten Bedingungen keine Aussch��ttung pro-inflammatorischer Zytokine, was darauf hinweisen k��nnte, dass nach Applikation diese Nanocarrier keine Entz��ndungsreaktion ausgel��st wird. W��hrend mit dPGS-NC keine Reduzierung der mitochondrialen Aktivit��t in oralen Epithelzellen mit unterschiedlich hohen Konzentrationen nachgewiesen werden konnte, zeigte der h(PG-co-PCL)S-NC nach 24 h mit der h��chsten Konzentration (c = 50 ��g/ml) eine leicht reduzierte mitochondriale Aktivit��t. Die durchgef��hrten Grundlagenexperimente stellen die Basis f��r die weitere Evaluation dieser Nanocarrier in den oralen epithelialen Geweben in vivo und in vitro dar.

Ökologisches Wirtschaften 29(4), 45-50 (2015). doi:10.14512/OEW300445 special issue: "Zeitwohlstand : vom Leben zwischen Effizienz und Entschleunigung", Published by ÖKOM, München

T cells in human neonates, infants, and adults differ dramatically in the initiation, strength, and stability of their responses. In this study, we investigate cellular mechanisms of CD4+ T cells from neonates, infants and adults to show the antigen specific response to Staphylococcus aureus and Bifidobacterium longum ssp. infantis. T cells from surgically excised adenoids of infants in different ages, cord blood and peripheral blood from healthy donors were characterized by flow cytometry and functional assays. Therefore CD14+ monocytes were incubated with extracts of Staphylococcus aureus and Bifidobacterium longum ssp. infantis to stimulate enriched T cells. CD4+ CD45RA and CD4+ CD45R0 T cells proliferate and up regulate the activation-associated molecule CD25 in response to Staphylococcus aureus whereas stimulation with Bifidobacterium longum ssp. infantis had no effect. In functional assays, we could show that T-cell proliferation is induced by Staphylococcus aureus via TCR-specific signal transduction. In this line, the antigen-specific response can be reduced by blockade of MHC class II molecules. Surprisingly, an inverse correlation between the percentages of Staphylococcus aureus induced proliferating T cells and age of infants is observed. In the case of activation with Staphylococcus aureus functional specific T cells are identified in cord blood, adenoids of infants, and adults with age-dependent characteristics. This work highlights the gap between specific T cell responses of neonates, infants, and adults in terms of quality and quantity. Our findings will help to understand the relationship between pathogens and T cells and to optimize future strategies for therapeutic interventions.

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