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Respiratory epithelial cells play a crucial role in the inflammatory response in endotoxin-induced lung injury, an experimental model for acute lung injury. To determine the role of epithelial cells in the upper respiratory compartment in the inflammatory response to endotoxin, we exposed tracheobronchial epithelial cells (TBEC) to lipopolysaccharide (LPS). Expression of inflammatory mediators was analyzed, and the biological implications were assessed using chemotaxis and adherence assays. Epithelial cell necrosis and apoptosis were determined to identify LPS-induced cell damage. Treatment of TBEC with LPS induced enhanced protein expression of cytokines and chemokines (increases of 235-654%, P < 0.05), with increased chemotactic activity regarding neutrophil recruitment. Expression of the intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-I (VCAM-I) was enhanced by 52-101% (P < 0.0001). This upregulation led to increased adhesion of neutrophils, with >95% adherence to TBEC after LPS stimulation, which could be blocked by either ICAM-1 (69%) or VCAM-1 antibodies (55%) (P < 0.05). Enhanced neutrophil-induced necrosis of TBEC was observed when TBEC were exposed to LPS. Reduced neutrophil adherence by ICAM-1 or VCAM-1 antibodies resulted in significantly lower TBEC death (52 and 34%, respectively, P < 0.05). Therefore, tight adherence of neutrophils to TBEC appears to promote epithelial cell killing. In addition to indirect effector cell-induced TBEC death, direct LPS-induced cell damage was seen with increased apoptosis rate in LPS-stimulated TBEC (36% increase of caspase-3, P < 0.01). These data provide evidence that LPS induces TBEC killing in a necrosis- and apoptosis-dependent manner. lipopolysaccharide; inflammatory mediators; leukocytes

Background: Transfusing blood products may induce inflammatory reactions within the vascular compartment potentially leading to a systemic inflammatory response. Experiments were designed to assess the inflammatory potential of different blood products in an endothelial cell-based in vitro model and to compare baseline levels of potentially activating substances in transfusion products. Methods: The inflammatory response from pre-activated (endotoxin-stimulated) and non-activated endothelial cells as well as neutrophil endothelial transmigration in response to packed red blood cells (PRBC), platelet concentrates (PC) and fresh frozen plasma (FFP) was determined. Baseline inflammatory mediator and lipid concentrations in blood products were evaluated. Results: Following incubation with all blood products, an increased inflammatory mediator release from endothelial cells was observed. Platelet concentrates, and to a lesser extent also FFP, caused the most pronounced response, which was accentuated in already pre-stimulated endothelial cells. Inflammatory response of endothelial cells as well as blood productinduced migration of neutrophils through the endothelium was in good agreement with the lipid content of the according blood product. Conclusion: Within the group of different blood transfusion products both PC and FFP have a high inflammatory potential with regard to activation of endothelial cells. Inflammation upon blood product exposure is strongly accentuated when endothelial cells are pre-injured. High lipid contents in the respective blood products goes along with an accentuated inflammatory reaction from endothelial cells. [ABSTRACT FROM AUTHOR]

Background: Acute renal failure is a frequent complication of sepsis. Hydroxyethyl starch (HES) is widely used in the treatment of such patients. However, the effect of HES on renal function during sepsis remains controversial. We established an in vitro model of tumor necrosis factor-alpha (TNF-alpha)-stimulated human proximal tubular epithelial (HK-2) cells to assess the possible effects of HES 130/0.42 and HES 200/0.5 on these activated cells., Methods: HK-2 cells were stimulated with TNF-alpha in the presence or absence of HES 130/0.42 or 200/0.5. After 4, 10, and 18 h of incubation, monocyte chemoattractant protein-1 (MCP-1), a key chemoattractant for neutrophils and macrophages, was measured. In addition, viability and cytotoxicity assays were performed., Results: MCP-1 expression was doubled upon TNF-alpha exposure. In the presence of 2% and 4% HES 200/0.5 in 98% (96%) medium over a stimulation time period of 10 h and 18 h, the MCP-1 concentration was decreased between 26% and 56% (P < 0.05). TNF-alpha stimulation resulted in a significant decrease of viability by 53%-63%, whereas viability decreased by only 32%-40% in coincubation with HES 130/0.42 (P < 0.005) and remained even less affected by TNF-alpha in the presence of HES 200/0.5 (P < 0.001). The TNF-alpha-induced cell death rate was attenuated in the presence of HES 200/0.5 (P < 0.05)., Conclusions: This in vitro study shows that both HES products modulate cell injury upon inflammatory stimulation. The effect was more pronounced in the HES 200/0.5 group than for HES 130/0.42, suggesting a possible biological difference between the HES types.

Background: Endotoxin-induced lung injury is a useful experimental system for the characterization of immunopathologic mechanisms in acute lung injury. Although alveolar epithelial cells (AEC) are directly exposed to volatile anesthetics, there is limited information about the effect of anesthetics on these cells. In this study we investigated the effect of pretreatment with the inhaled anesthetic sevoflurane on lipopolysaccharide (LPS)-injured AEC., Methods: AEC were incubated with 1.1 vol % sevoflurane for 0.5 h, followed by LPS stimulation for 5 h. Expression of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1beta (MIP-1beta), macrophage inflammatory protein-2 (MIP-2), cytokine-induced neutrophil chemoattractant-1 (CINC-1), and intercellular adhesion molecule-1 (ICAM-1) was analyzed. In addition, functional tests were performed through chemotaxis and adherence assays to underline the biological relevance of the findings., Results: Exposure of AEC to sevoflurane resulted in a 50% downregulation of MCP-1 protein in the sevoflurane-LPS group when compared with non-sevoflurane- LPS cells (P < 0.05). MIP-1beta concentration in LPS-stimulated cells decreased by 32% with sevoflurane (P < 0.05), MIP-2 by 29% (P < 0.05), and CINC-1 by 20% (P < 0.05). ICAM-1 protein expression was attenuated by 36% (P < 0.05). This inhibition caused substantial changes in the inflammatory response of neutrophils. 33% less chemotactic activity was seen in sevoflurane-treated LPS cells (P < 0.001) as well as 47% decreased adhesion of neutrophils to AEC (P < 0.001)., Conclusions: This study shows that sevoflurane alters the LPS-induced inflammatory response, not only with respect to the expression pattern of inflammatory mediators, but also regarding the biological consequences with less accumulation of effector cells such as neutrophils.