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Die chirurgische Behandlung von schwerheilenden bzw. großflächigen Wunden wird ständig modifiziert, hierzu zählen mesh graft Transplantationen, der Einsatz von Keratinozytensuspensionen und azelluläre dermale Äquivalente. Obwohl epidermale Äquivalente und Spalthaut[for full text, please go to the a.m. URL], 30. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung (DAV 2012)

Es wurde eine zellbasierte Wundauflage mit Keratinozyten und Fibroblasten auf Basis einer kommerziellen Wundauflage (Matriderm, Collagen/Elastin-Matrix) generiert, um damit großflächige Verbrennungswunden behandeln zu können. Zunächst wurde die Expansion der Keratinozyten optimiert[for full text, please go to the a.m. URL], DAV 2009; 27. Jahrestagung der deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung

Cellular rejection mechanisms are characterized by the infiltration of sensitized lymphocytes through the donor endothelium into the transplanted organ. The regulation of cellular adhesion molecules by soluble mediators (cytokines) is thought to play a dominant role in this process. In the present study the kinetics of lymphocyte infiltration were examined using a new established in vitro model and compared to the kinetics of adhesion molecule expression.Peripheral blood lymphocytes (PBL) of healthy volunteers were pipetted to allogeneic endothelial cell (EC) monolayers and binding rates evaluated after different incubation times. Adherent PBL could be distinguished from penetrated PBL by means of a combined phase contrast- / reflection interference contrast - microscope.30-35% of all pipetted PBL adhered to unstimulated EC maximally. Out of these cells10% penetrated through the endothelium ( = maximum penetration). The cytokines alpha-, beta-, gamma-interferon (IFN) or IL-1 did not enhance maximum adhesion, but accelerated this process. However, a 2 hrs prestimulus of EC by these cytokines was necessary to induce acceleration. Maximum penetration was enhanced by alpha-, beta-, gamma-IFN, but not by IL-1, irrespective whether PBL were added together with cytokines to unstimulated EC or to already prestimulated EC. Immunocytochemical and fluorometric analyses of adhesion molecule expression revealed a cytokine induced upregulation or de novo expression of the adhesion antigens ICAM-1, ELAM-1 and VCAM-1 on EC membranes. Interestingly, PBL adhered to EC before upregulation or de novo expression of adhesion molecules was detected.The results showed that PBL adhesion and penetration processes were regulated differentially by cytokines. The early phase of PBL attachment to EC seemed not to be influenced by adhesion antigens but by an activation of the lymphocyte cytoskeleton.

Shielding the organism against harmful effects from the environment is one of the most important tasks of the outer covering of all animals. The epidermis of primarily aquatic organisms and the epithelia of organs which are exposed to water, such as the digestive or the urinary system, possess a film of glycoproteins and mucopolysaccharides, the glycocalyx. This short paper examines the relationship of the mucus cells with the glycocalyx. Translated from German into English

The effect of digitoxin (CAS 71-63-6) and ouabain (g-strophantin, CAS 630-60-4) on respiration, morphology and beating activity of cardiomyocytes in culture derived from embryonic chick hearts has been investigated. The drugs were applied in a perfusion system using a protein- and substrate-free perfusion medium (BSS) at two concentration of K+ (5.4 and 4 mmol/l). In either K+ concentration oxygen consumption was 0.13 +/- 0.05 nmol O2 h-1 per 1000 cells. During 3 h of perfusion with BSS oxygen consumption declines only slightly to 79 +/- 15% of the initial value. No relation was found between beating frequency and oxygen consumption. Increase in respiration ranged from 5 to 45% and lasted between 5 and 120 min. At concentrations being inhibitory to the Na+/K(+)-ATPase (greater than or equal to 1 mumol/l) ouabain stimulated respiration by about 20% at 4 mmol/l K+ and 10% at 5.4 mmol/l K+ while digitoxin was effective at 5.4 mmol/l only (a transient increase of 20%). At 0.1 nmol/l, (a concentration below the KD of the high affinity binding site of the Na+/K(+)-ATPase) ouabain caused a long lasting activation of respiration by about 30%, digitoxin induced a transient rise of up to 20% at 5.4 mmol/l K+. At 4 mmol/l K+ digitoxin did not affect respiration while ouabain caused a transient increase. The lowest concentration of ouabain inducing a reproducible activation of oxygen consumption was 0.1 pmol/l. At this concentration digitoxin was no longer effective. At 1 fmol/l respiration was stimulated only occasionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Lymphocyte infiltration through vascular endothelium is one important step in the course of graft rejection. To investigate this process more exactly we established a monolayer invasion assay which enabled us to discriminate between adherent and penetrated cells. Detailed studies of adhesion and penetration kinetics of peripheral blood lymphocytes (PBL) acting on allogeneic human umbilical vein endothelial cells (HUVEC) were carried out by combined phase contrast and reflection interference contrast microscopy. Between 30 and 35% of all PBL attached to HUVEC after 4 hr. Out of these less than 10% penetrated. When HUVEC were prestimulated for 2 hr by interferon (IFN)-alpha,-beta,-gamma or interleukin (IL)-1, PBL adhesion in the early phase of cellular attachment to endothelial cells was accelerated. Overall adhesion however did not increase. Long-term pretreatment of HUVEC for 72 hr with IFN-gamma or IL-1 also modified PBL-HUVEC interactions. However, a 72-hr pretreatment with IFN-alpha or -beta did not influence lymphocyte binding behaviour. PBL penetration was not only accelerated but also enhanced by IFN-alpha,-beta,-gamma, irrespective of whether HUVEC were prestimulated for 2 hr or PBL and cytokines were added simultaneously to HUVEC. On the other hand IL-1 was not able to enhance the amount of penetrated cells but only accelerated the infiltration process. Up-regulation or de novo expression of the adhesion molecules ICAM-1 (intercellular adhesion molecule), ELAM-1 (endothelial leucocyte adhesion molecule) and VCAM-1 (vascular cell adhesion molecule) did not parallel PBL binding kinetics. Therefore an ICAM-, ELAM- and VCAM-independent modulation in the early phase of lymphocyte attachment to endothelium seems likely. The lymphocyte cytoskeleton may have a role in this process.