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Background: The aim of this study was to establish a new experimental model to directly analyse the coronary microcirculation in cardiac xenografts. Methods: Intravital fluorescence microscopy (IVM) of the subepicardial microcirculation in heterotopically transplanted hamster-to-rat cardiac xenografts was performed at 30 and 90 min of reperfusion. We quantitatively assessed the microcirculatory perfusion characteristics as well as the interactions of leukocytes and platelets with the endothelium of postcapillary coronary venules in non-sensitised as well as sensitised recipients. Results: In this first experimental IVM study of cardiac xenografts, we successfully visualised the subepicardial microcirculation, i.e. feeding arterioles, nutritive capillaries and draining postcapillary venules, during reperfusion. Leukocyte-endothelial and platelet-endothelial cell interactions could be quantified. In the non-sensitised group, the myocardial microcirculation remained stable during the observation period of 90 min, whereas in the sensitised group, xenografts were rejected immediately. Conclusions: We established a model for the assessment of the microcirculatory dysfunction and inflammation during ischaemia/reperfusion injury in hamster-to-rat cardiac xenografts.

Background. The aim of our study was to investigate the role of inducible nitric oxide synthase (iNOS)-derived nitric oxide (NO) production in different stages of murine antigen-induced arthritis (AiA). Methods. Clinical, histological and microcirculatory parameters (measured by intravital fluorescence microscopy) were assessed in the knee joint during acute and chronic AiA after inhibition of iNOS with L-N 6 -(1-iminoethyl)lysine (L-NIL). Plasma concentrations of NO - 2 and NO - 3 were evaluated by the Griess reaction and the expression of iNOS, P- and E-selectin, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule I (VCAM-1) by immunohistochemistry. Results. In both stages of the disease, plasma concentrations of NO, and NOR were increased and iNOS was expressed. In the acute phase, swelling, leucocyte adhesion, leucocyte infiltration and expression of adhesion molecules were increased in arthritic animals treated with L-NIL in comparison with untreated arthritic animals. In the chronic phase, no change in the disease parameters could be detected after L-NIL treatment. Conclusion. Increased NO production induced by iNOS during the acute phase of AiA can be regarded as a protective response in the prevention of further leucocytic infiltration and joint destruction, whereas it seems to play a subordinate role in chronic AiA.

The microcirculation and leukocyte-endothelial cell interaction in synovial tissue of an inflamed joint are known to play a crucial role in the pathogenesis of rheumatoid arthritis. The aim of this study was to characterize the in vivo changes in the microvasculature and in leukocyte-endothelial cell interactions in the mouse synovial tissue using intravital fluorescence microscopy in three stages of antigen-induced arthritis. The expression of E- and P-selectin and ICAM-1 were also studied using immunohistochemistry.Antigen-induced arthritis (AiA) was produced in Balb/c mice. The severity of arthritis at three different phases was quantified using a clinical and histological score. For the intravital fluorescence microscopy measurements, the patella tendon was partially resected for visualization of the intraarticular synovial tissue of the knee joint. The number of rolling and adherent leukocytes, functional capillary density (FCD) and RBC velocity were quantitatively measured in synovial microvessels. Expression of ICAM-1, E- and P-selectin was assessed by immunohistochemistry.There was a significant increase in the leukocyte rolling fraction in postcapillary venules in the acute phase of AiA (from 0.26 +/- 0.05 in controls to 0.45 +/- 0.04 8 d after AiA induction). The number of leukocytes adherent to the endothelium was significantly elevated in all phases of arthritis (from 121 +/- 27 in controls to 376 +/- 62 mm2 63 d after AiA-induction). Functional capillary density was significantly enhanced in the acute (332 +/- 15 cm/cm2) and intermediate phases (320 +/- 15 cm/cm2) compared to control values (227 +/- 15 cm/cm2). Arthritis resulted in a distinct increase in the expression of ICAM-1 on the synovial endothelium in all phases of AiA. E- and P-selectin expression were detected only in the acute phase.Our model provides new insights into the microcirculatory changes which occur in the synovial tissue of an arthritic joint.

Halogenated anaesthetics have been shown to reduce ischaemia-reperfusion injuries in various organs due to pre- and post-conditioning mechanisms. We compared volatile and total intravenous anaesthesia with regard to their effect on remote pulmonary injury after thoracic aortic occlusion and reperfusion.Eighteen pigs were randomized after sternotomy and laparotomy (fentanyl-midazolam anaesthesia) to receive either sevoflurane or propofol in an investigator-blinded fashion. Ninety minutes of thoracic aortic occlusion was induced by a balloon catheter. During reperfusion, a goal-directed resuscitation protocol was performed. After 120 min of reperfusion, the anaesthetic regimen was changed to fentanyl-midazolam again for another 180 min. The oxygenation index and intra-pulmonary shunt fractions were calculated. After 5 h of reperfusion, a bronchoalveolar lavage was performed. The total protein content and lactate dehydrogenase activity were measured in epithelial lining fluid (ELF). Alveolar macrophage oxidative burst was analysed. The wet to dry ratio was calculated and tissue injury was graded using a semi-quantitative score. Ten animals (n=5 for each anaesthetic) without aortic occlusion served as time controls.The oxygenation index decreased and the intra-pulmonary shunt fraction increased significantly in both occlusion groups. There were no significant differences between sevoflurane and propofol with respect to the oxygenation index, ELF composition, morphologic lung damage, wet to dry ratio and alveolar macrophage burst activity. Differences were, however, seen in terms of systemic haemodynamic stability, where catecholamine requirements were less pronounced with sevoflurane.We conclude that the severity of remote lung injury was not different between sevoflurane and propofol anaesthesia in this porcine model of severe lower-body ischaemia and reperfusion injury.

In dieser in vivo Studie beschreiben wir den Typ, die Kinetik und die mikrovaskulare Lokalisation der Rekrutierung von CD4+ T-Zellen in der postischamischen Leber. CD4+ T-Zellen interagieren mit Thrombozyten in den postischamischen Sinusoiden; diese Interaktion wird durch Bindung des thrombozytaren CD62P an den entsprechenden Liganden PSGL-1 auf T-Zellen mediiert, wahrend die reziproke Aktivierung beider Zelltypen durch die CD40-CD40L-Interaktion vermittelt wird. CD4+ T-Zellen aktivieren das sinusoidale Endothel, und verstarken die I/R-induzierte Thrombozytenakkumulation sowie den mikrovaskularen hepatischen I/R-Schaden durch die CD40-CD40L and CD28-B7 Signalwege ohne Beteiligung von MHC Klasse II-Molekulen.

Nitric oxide production by the inducible NO-synthase in the synovium and chondrocytes is known to be enhanced during chronic joint inflammation and aseptic loosening of joint prostheses. Due to the distinct side effects of non-selective NO-inhibitors on the macro- and microhemodynamics, we investigated the in vivo changes after selective (N-iminoethyl-L-lysine (NIL)) versus non-selective NO-synthase inhibition (NG-nitro-L-arginine methyl ester (L-NAME)) in the synovium of the mouse knee joint. Our results show a significant decrease in the functional capillary density and an increase in the leukocyte accumulation after L-NAME injection. In contrast, NIL did not alter the microhemodynamics or the leukocyte-endothelial cell interaction in the synovium, indicating its potential use for therapeutic selective inhibition of iNOS in joint inflammation.

The inhibition of angiogenesis might be a therapeutic approach to prevent joint destruction caused by the overgrowing synovial tissue during chronic inflammation. The aim of this study was to investigate angiogenesis in the knee joint of mice with antigen-induced arthritis (AiA) by means of intravital microscopy. Material and Methods: Intravital microscopic assessment was performed in 14 female mice (C57BL6/129SV) on day 8 after AiA induction in two groups (controls, animals with AiA). After preparation of the knee joint under inhalation anesthesia, synovial tissue was investigated by fluorescence microscopy using the plasma marker FITC-dextran (150 kDa). Quantitative assessment of vessel density was performed according to the following categories: “functional capillary density” (FCD, vessels < 10 µm in diameter),“functional vessel density” (FVD, vessels ≥ 10 µm) and FVD of “vessels with angiogenic criteria” (at least one of the following: convoluted vessel, abrupt changes in diameter, unphysiologic branching). After immunostaining of tissue sections with a monoclonal antibody against von Willebrand factor, vessel density (stained endothelium) was quantified as microvessel count/area. Results: There was no significant difference in FCD between the control group (337±9 cm/cm2; mean±SEM) and the AiA group (359±13). However, the density of vessels ≥10 µm in diameter was significantly increased in animals with AiA (135±10 cm/cm2 vs. 61±5 control). Furthermore, the density of blood vessels “with angiogenic criteria” was enhanced in arthritic animals (79±17 cm/cm2 vs. 12±2 control). In addition, there was a significant increase in the “microvessel count” in arthritic animals (297±25 mm-2 vs. 133±16 control). Conclusion: These findings demonstrate that angiogenesis in murine AiA can be assessed quantitatively using intravital microscopy. Further studies will address antiangiogenic strategies in AiA.

Background: Inhalation of high concentrations of oxygen can lead to hyperoxie lung injury. We could already show that hyperoxia can increase nitric oxide (NO) production in alveolar macrophages (AM) after stimulation with LPS and IFN-γ in comparison to normoxic exposure. The mechanism, however, is not fully understood. Therefore, we investigated the effects of hyperoxia on intracellular reactive oxygen species (ROS), their influence on redox sensitive transcription factors NF-κ and AP-1 and regulation of iNOS expression. Methods: AM were obtained by bronchoalveolar lavage of anesthetized CD rats. Cells were incubated under 21% or 85% 02 and treated with 100 ng/ml LPS and/or 100 U/ml IFN-γ for 24 h. ROS were detected fluorometrically by quantitating oxidation of 2’,7’- dichlorofluorescin. Inhibition of ROS was determined using N-acetyl L-cysteine (NAC) (30 mM) and pyrrolidine dithiocarbamate (PDTC) (50 µM) as antioxidants. Activation of redox-sensitive transcription factors NF-κB and AP-1 was analysed using electrophoretic mobility shift assays (EMSA) and induction of iNOS mRNA was investigated by RT-PCR. Results: Hyperoxia caused a significant increase in intracellular ROS production after stimulation with LPS/IFN-γ (LPS/IFN-γ 21% O2, 200.3±6.3% of control; LPS/IFN-γ 85% O2, 246.2±24.7% of control). Treatment with NAC and PDTC led to a dramatic decrease in intracellular ROS levels after stimulation with LPS/IFN-γ under normoxia as well as under hyperoxia (LPS/IFN-γ + NAC 21% O2, 123.5±5.1% of control; LPS/IFN-γ + NAC 85% O2, 122.8±5.7% of control; LPS/IFN-γ + PDTC 21% O2 ,151.3±1.3% of control; LPS/IFN-γ + PDTC 85% O2, 168.5±3.8% of control). Activation of redox-sensitive transcription factors NF- κB and AP-1 was elevated under hyperoxia in unstimulated AM and after stimulation with LPS/IFN-γ in comparison to normoxic exposure. INOS induction after treatment with LPS/IFN-γ was further enhanced under hyperoxic conditions and inhibited by adding the antioxidants NAC or PDTC under normoxia as well as hyperoxia. Conclusion: Our results indicate that there is an increased production of intracellular ROS under hyperoxia that plays an important role in activating redox-sensitive transcription factors and regulating iNOS gene expression. We conclude that ROS play a key role in the pathogenesis of hyperoxic lung injury.

Human recombinant interleukin-10 (rhIL-10) has been found to inhibit endotoxin-induced production of several proinflammatory cytokines including tumor necrosis factor alpha (TNFalpha) from human monocytes. The exogenous therapeutic administration of rhIL-10 in acute and chronic hyperinflammatory conditions has been discussed. For none of the large animal species that have been used to study the role and effects of various mediators during septicemia, crossreactivity of rhIL-10 has been shown so far. Therefore, the aim of the present investigation was to evaluate the crossreactivity of rhIL-10 in a porcine model.To determine the effects of rhIL-10 on endotoxin-challenged porcine monocytes, we incubated porcine peripheral blood monocytes from five donors with three different concentrations of rhIL-10 (500 ng/ml, 1000 ng/ml and 2000 ng/ml, respectively) either simultaneously with, or two hours prior to lipopolysaccharide (LPS) administration.As compared to incubation with LPS (1 microg/ml) alone, coincubation with LPS and rhIL-10 (500 ng/ml, 1000 ng/ml and 2000 ng/ml) (n = 5) for four hours resulted in a marked and uniform reduction of immunoreactive TNFalpha. For preincubation (n = 5), only the addition of 500 ng/ml rhIL-10 led to a homogeneous decrease of TNFalpha levels in each sample. There was no consistent reduction in TNFalpha after preincubation with 1000 and 2000 ng/ml rhIL-10. Our results indicate crossreactivity of recombinant human interleukin-10 in porcine peripheral blood monocytes. Further investigations on the potential therapeutical role of exogenously administered rhIL-10 are thus possible in porcine models.

The microcirculation is the organ that provides the direct link between blood and tissue, and thereby between the whole organism and the single cell. Modern microcirculation research in experimental surgery is characterized by the use of high-resolution video fluorescence microscopy and quantitative computer-assisted image analysis coupled with the techniques of molecular biology and transgenic or knockout gene technology. These advances should improve knowledge about surgically relevant physiologic and pathophysiologic phenomena at the interface between blood and tissues and help us to understand the initial molecular mechanisms leading to organ dysfunction following inflammation, ischemia-reperfusion, and transplantation.

Pulmonary toxicity of inhaled materials is often evaluated by (repetitive) assessment of the composition of bronchoalveolar lavage (BAL) fluid or of epithelial lining fluid (ELF) in sheep and lambs. Knowledge of the typical constituents of these fluids obtained from healthy animals is essential for identification of pathologic changes. Few studies have dealt with normal constituents of BAL fluid or ELF in sheep and lamb. The comparability of these studies, however, is limited for reasons concerning the choice of model and BAL technique. The biochemical and cellular composition of alveolar ELF obtained by a standardized BAL procedure was examined in 15 pento-barbital anesthetized 4 months old Merino lambs unexposed to inhaled substances. ELF volume was calculated by using the urea dilution method. We found 20.3 x 10(5) leucocytes per ml ELF, 87.5% of which were alveolar macrophages. Basophils and neutrophils were practically absent while 5% of the counted cells were lymphocytes. 76% of recovered cells were viable. The ELF contained 7 mg/ml total protein; enzyme activities of LDH and AP were 1692 U/l and 145 U/l, respectively.

Exposure to high concentrations of oxygen is known to induce changes in lung function through effects on several pulmonary cell types, including alveolar macrophages (AM). In this study, we studied the in vitro effects of hyperoxia on the release of proinflammatory cytokines and the expression of surface receptors in AM obtained from cynomolgus monkeys by bronchoalveolar lavage under general anesthesia. AM were exposed for 24 h to moderate (50% O(2)) or severe (95% Osub2) hyperoxia in the absence or presence of LPS, and the release of IL-1beta, IL-6, and TNF-alpha was measured in culture supernatants by ELISA. In addition, the expression of the surface molecules HLA-DR, CD14, and CD11b was assessed by flow cytometry. Exposure to 95% O2 activated resting AM to produce significantly increased amounts of IL-1beta and IL-6. Moreover, hyperoxia amplified the release of TNF-alpha by LPS-stimulated AM in an oxygen tension-dependent manner. Finally, exposure to 95% O2 upregulated the expression of the adhesion molecule CD11b on AM, whereas the expression of HLA-DR and CD14 was not affected. These findings support the view that hyperoxia-induced activation of AM may represent an initial event in the proinflammatory sequence caused by hyperoxia.

Farmer’s lung is a frequent form of extrinsic allergic alveolitis that is induced by inhalation of antigens found in mouldy hay. We have previously shown that in patients with acute episodes of farmer’s lung circulating neutrophils are primed for an enhanced respiratory burst [1]. To further characterize the alveolitis in acute episodes of farmer’s lung, we measured cytokine and endotoxin levels in the bronchoalveolar lavage (BAL) fluid of farmer’s lung patients after inhalative provocation and analysed the expression of leukocyte activation markers and adhesion molecules on both blood and BAL cells pre- and post-exposure.

Fibrosing alveolitis (FA) is a common and often fatal complication of systemic sclerosis (SSC). The purpose of this study was to characterize the fibrotic process within the lungs using bronchoalveolar lavage fluid (BALF). We investigated 25 healthy controls (CON) and 85 SSC patients. In 61 patients (72%) lung function tests, clinical, and radiological findings indicated manifest FA, whereas 24 patients (28%) where free of significant lung disease. Of the latter, 12 had pathologic BAL differential cell counts (= subclinical alveolitis; SUB), 12 had normal BAL cytology (NOR). BAL samples were analysed for chemoattractant activity (CAA) for fibroblasts using Boyden chambers. Procollagen-III-Peptide (P-III-P) and Laminin fragment P1 (Lam-P1) were measured radioimmunologically. CAA (expressed as % of the effect of conditioned medium) was increased in FA and SUB (CON: 17.3 +/- 3.2; FA: 40.8 +/- 5.8, p0.01 vs. CON; SUB: 58.6 +/- 11.8, p0.01 vs. CON; NOR: 23.7 +/- 6.3; n.s.). Lam-P1 [U/ml ELF] was also elevated in FA and SUB patients (CON: 0.90 +/- 0.17; FA: 2.07 +/- 0.48, p0.05 vs. CON; SUB: 2.61 +/- 1.14, p0.05 vs. CON; NOR: 1.05 +/- 0.35, n.s. vs. CON). P-III-P [U/ml ELF] was elevated in FA patients (CON: 8.3 +/- 1.1; FA: 26.9 +/- 5.5, p0.001 vs. CON) but not in SUB or NOR (SUB: 10.2 +/- 0.7, NOR: 7.9 +/- 2.9; n.s.). There was no significant relationship between P-III-P and LAM-P1 values in ELF and serum, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Rhodamine 6G is a vital dye accumulating in the mitochondria of cells. It is used in intravital fluorescence microscopy for contrast enhancement of white blood cells (WBC), enabling visualization of WBC in the microvasculature even at high center flow velocity. The aim of this study was to examine the kinetics of WBC staining after intravascular administration of rhodamine 6G in Lewis rats, Syrian golden hamsters and BALB/c mice. For this purpose, WBC were isolated from whole blood and the percentage of cells stained positively as well as their fluorescence intensity were measured by flow cytometry 5, 15, 30 and 60 min after dye administration. Injection of 0.06-0.2 mg/kg body weight of rhodamine 6G resulted in staining practically all granulocytes and monocytes over the entire observation period of 60 min. Fluorescence intensity of WBC was adequate to be detected in an experimental setup for intravital fluorescence microscopy in the hamster dorsal skinfold chamber. The degree of WBC staining was different in the species studied, yielding a higher percentage of stained lymphocytes in rats than in mice and hamsters. Staining of lymphocytes declined within 60 min after rhodamine application, the loss of fluorescent label being most pronounced in hamster cells. After 15-30 min, relative fluorescence intensity of stained lymphocytes had decreased considerably, indicating the need for reinjection of the dye or limiting microscopic analysis to approximately 15 min after rhodamine 6G administration. While the intravascular injection of rhodamine 6G results in adequate staining of granulocytes and monocytes, only a fraction of lymphoid cells are stained.

Oxidized LDL (oxLDL) has been identified as a potent stimulus of leukocyte adhesion to endothelium, a hallmark of early atherogenesis. A cytofluorometric study was performed to further characterize the mechanisms by which oxLDL stimulates the rapid adhesion of leukocytes to endothelium in vitro and in vivo. Incubation (30 minutes at 37 C) of whole blood (diluted with buffered saline to 1 x 10(6) leukocytes/ml) with oxLDL (0.85 mg LDL cholesterol/ml; oxidized by 7.5 mumol/L Cu2+ for 18 hours) but not native LDL stimulated the upregulation of CD11b/CD18 adhesion receptors on neutrophils (anti-leu-15 binding: 178 +/- 16% of baseline, P < 0.01, means +/- SD of n = 10 experiments) and on monocytes (169 +/- 34% of baseline, P < 0.01). This phenomenon was almost entirely inhibited by n-butanol or the vasoactive drug pentoxifylline (PTX), which also significantly reduced oxLDL-induced leukocyte adhesion to venular and arteriolar endothelium, as assessed by intravital microscopy on the dorsal skinfold chamber in hamsters (venules: 49 +/- 19 versus 120 +/- 34 cells/mm2, P < 0.05; arterioles: 9 +/- 4 versus 52 +/- 7 cells/mm2, P < 0.01) 30 minutes after intravenous injection of oxLDL (4 mg/kg body weight; means +/- SD of n = 7 hamsters per group). Butanol and PTX also significantly reduced the upregulation of CD11b/CD18 by f-methionyl-leucyl-phenylalanine (fMLP) and platelet-activating factor (PAF) but not by phorbol myristate acetate (PMA). Whereas fMLP and PAF stimulate leukocytes via binding to specific cell surface receptors and triggering complex signal transduction pathways, PMA bypasses these pathways and directly activates intracellular protein kinase C. By analogy, we propose that oxLDL upregulates CD11b/CD18 through its previously documented ability to stimulate the generation of second messengers. The effect of n-butanol and PTX on receptor presentation cannot be explained by changes in plasma membrane fluidity, as both agents failed to reverse the decrease in plasma membrane fluidity of neutrophils after stimulation with oxLDL, as assessed by fluorescence anisotropy measurement of the membrane marker diphenylhexatriene. Incubation of isolated neutrophils but not of whole blood with oxLDL resulted in a significant loss of L-selectin from the neutrophil surface (anti-TQ-1 binding: 40 +/- 13% of baseline, P < 0.01). A significant loss of this adhesion receptor on neutrophils and monocytes was also observed after stimulation of isolated neutrophils and whole blood with fMLP, PAF, and PMA.(ABSTRACT TRUNCATED AT 400 WORDS)

Lipopolysaccharide causes activation of monocytes/macrophages with excessive secretion of cytokines resulting in hypotension and shock in patients with sepsis. Lipopolysaccharide may induce these responses by interacting with lipopolysaccharide-binding protein and then binding to the cell surface protein CD14 or by acting directly with CD11-CD18 on monocytes/macrophages. The role of CD14 and CD11-CD18 in the activation of macrophages with enhanced cytokine transcription in patients with septic shock remains to be determined.To study this, heparinized blood was obtained from 16 patients with septic shock on days 0, 1, 3, 5, 7, and 10 and compared with 20 control patients. The expression of CD14 and CD11b on monocytes in whole blood was measured by direct immunofluorescence and flow cytometry. Moreover, whole blood was stimulated with lipopolysaccharide (1 microgram/ml) for 0, 1, 2, 4, 8, and 24 hours, and messenger RNA expression for tumor necrosis factor-alpha, interleukin-beta (IL-1 beta), and IL-6 was determined on isolated peripheral blood mononuclear cells with Northern blot analysis.Both CD14 expression and receptor density on monocytes from whole blood were markedly suppressed (-63% on day 3; p0.05) in the septic group compared with controls. Although CD11b expression was also decreased (-24% on day 1; p0.05), receptor density on monocytes was slightly increased in the septic group in comparison with the control group. Kinetics and intensity of messenger RNA expression for tumor necrosis factor-alpha, IL-1 beta, and IL-6 were similar in both groups.These data indicate that in patients with septic shock, lipopolysaccharide-mediated signaling and cytokine transcription are unchanged despite a significant reduction of CD14 expression and density on monocytes. Thus, lipopolysaccharide-induced activation of monocytes from patients with sepsis may occur through direct binding of lipopolysaccharide to the CD11-CD18 complex or other lipopolysaccharide receptors, whereas binding of the lipopolysaccharide-lipopolysaccharide-binding protein complex to the CD14 receptor may not play a pivotal role in sepsis.

BACKGROUND--In fibrosing alveolitis activation of lung fibroblasts is the decisive event in the pathogenetic sequence leading to pulmonary fibrosis. Fibroblast stimulating activity was measured in bronchoalveolar lavage (BAL) fluid to assess its relationship to the activity of fibrosing alveolitis. METHODS--Nine control subjects and 40 patients with fibrosing alveolitis caused by idiopathic pulmonary fibrosis (n = 22) or pulmonary involvement in systemic sclerosis (n = 18) were studied. All patients were followed up by lung function testing for a minimum of six months (mean (SE) 13.3 (1.4) months). Twenty five patients received immunosuppressive therapy and 15 refused. At the beginning of follow up BAL was performed and, as a possible indicator of fibroblast stimulating mediators within the lungs, chemotactic migration of cultured human fibroblasts elicited by native BAL fluid was measured in Boyden-type chambers and expressed as a percentage of the chemoattractant effect of 25 ng/ml platelet derived growth factor. The procollagen III peptide level in BAL fluid served as a marker for collagen synthesis. RESULTS--Chemoattractant activity was elevated in the patients with idiopathic pulmonary fibrosis and systemic sclerosis compared with the control group, (mean (SE) 56.4% (8.5%)) and 72.3% (16.3%) v 12.6% (4.0%). Chemoattractant activity was inversely correlated with total lung capacity (TLC) (r = -0.45) and with vital capacity (VC) (r = -0.33). Procollagen III peptide concentrations in BAL fluid and chemoattractant activity were not significantly correlated. For further evaluation chemoattractant activity of 36% (mean value of controls +2 SD) was used to separate normal (< 36%) from elevated (> or = 36%) activity. At the end of follow up, untreated patients with high chemoattractant activity (> or = 36%) showed a significant reduction of VC, TLC, and exercise arterial oxygen tension (PaO2) and a small decrease in carbon monoxide transfer factor (TLCO), whereas a significant improvement in VC, TLC, and TLCO and a small increase of exercise PaO2 occurred in treated patients with high chemoattractant activity. Patients with low chemoattractant activity (< 36%) showed no consistent change in lung function measurements, irrespective of treatment. In contrast, lung function results and differential cell counts in BAL fluid failed to identify progressive disease. CONCLUSIONS--In patients with fibrosing alveolitis the chemoattractant activity of BAL fluid seems to be an independent indicator of lung fibroblast stimulating activity providing relevant information about disease activity, and may help to improve the clinical management of these patients.

Die Ischamie und Reperfusion der Leber konnen zu Einschrankungen der Organfunktion bis zum Leberversagen fuhren. Als Ursache fur die Beeintrachtigung der Hepatocyten- funktion wird neben Storungen der Mikrozirkulation eine Beteiligung inflammatorischer Mediatoren (TNF-α, IL-6, IL-1, Prostaglandine) diskutiert, die von Kupfferzellen unter diesen pathophysiologischen Bedingungen in erhohtem Mas freigesetzt werden. Es gibt Hinweise dafur [1, 2], das Hepatocytenfunktionen nach Ischamie/Reperfusion durch die veranderte Freisetzung von Mediatoren aus Kupfferzellen reguliert werden. Es war das Ziel dieser Studie, die veranderte Sekretion von TNF-α und IL-6 (hepatocyte-stimulating-factor) aus Kupfferzellen an einem Leberischamiemodell zu untersuchen.

Postoperative survival of human heart recipients depends mainly on the early diagnosis and prevention of inflammatory events. Different therapeutic regimens, e.g. immunosuppressive drugs or antibiotics, enable transplant surgeons to treat such complications successfully. Non-invasive and reliable methods for the early detection of inflammation in graft recipients are desired in order to avoid major organ damage.

In a transplantation model using Dark Agouti rats as heart donors and Lewis rats as recipients, mean graft survival time was 7.1 days in GII, receiving no immunosuppression, and 31.4 days in GIII, animals immunosuppressed by DSG. A higher percentage of Lb in the spleen than in the PB in the transplanted groups was detected on certain days. HCT sharply decreased in immunosuppressed animals, thus suggesting a reversible suppression of erythropoesis induced by DSG.

Die bronchoalveolare Lavage ist heute als eine routinemasig anzuwendehde Methode zur Gewinnung cellularer oder humoraler Faktoren aus dem Bronchoalveolarraum etabliert (1). Zur Verlaufskontrolle ist es bei bestimmten experimentellen bzw. klinischen Untersuchungsprotokollen wunschenswert, die BAL wiederholt durchzufuhren. Aus mehreren Untersuchungen ist bekannt, das die BAL-Prozedur einen Einstrom neutrophiler Granulocyten in den Bronchoalveolarraum induziert (2, 3). Widerspruchlich diskutiert wird, ob dieser BAL-Effekt lokal begrenzt ist oder ob er auch andere, initial nicht lavagierte Lungenareale betrifft (4, 5). Von besonderer klinischer Relevanz ist die Frage, ob die uber einen langeren Zeitraum wiederholte Durchfiihrung der BAL zu Veranderungen bzw. Schaden bronchoalveolarer Strukturen fuhrt.

The following is based on an experimental animal study of Javanese macaques examined by high resolution CT at the end of 27 months exposure to defined amount of quartz and/or high atmospheric pressure [1].

High resolution, narrow section CT examinations of the lungs were carried out on 21 Javanese macaques (five controls) shortly before the conclusion of 27 months exposure to quartz and/or high pressure. The aim was to establish morphometric CT data for differentiating and quantifying normal and abnormal findings. The results show that the technique has a high sensitivity for demonstrating the pathological lung changes. Final validation depends upon the use of respiratory physiology and biochemical, cytological, and histomorphometric data.

During organ graft rejection, soluble mediators of inflammation are released into the polymorphs (PMNs) and monocytes recruited from the blood. One functional capacity of polymorphs and monocytes/macrophages is the production of cytotoxic activated oxygen species upon stimulation, which may contribute to the rejection process. Nothing is known about the influence of allograft rejection on this inflammatory cell property. Chemiluminescence (CL) allows measurement of respiratory burst capacity in small cell samples. Zymosan-induced and luminol-amplified CL of diluted whole blood, separated PMNs, and mononuclear cells from peripheral venous blood, as well as of intragraft phagocytes was measured after allogeneic and autologous kidney transplantation in untreated dogs. CL of separated PMNs, mononuclear cells, and intragraft phagocytes was significantly elevated during allograft rejection. In autologous kidneys transplanted to recipients of allografts, CL was also increased in the autologous grafts during rejection of the allogeneic ones, indicating a systemic alteration in phagocyte function.

Infrared contact coagulation (ICC) was evaluated in 3 different tumor models. 56-94% of all tumor-bearing rats, hamsters or mice were cured by ICC, whereas 100% of the controls died. The possibility that long-lasting immunological resistance might develop against the tumor after ICC was investigated by repeated tumor challenge. Cytotoxicity against tumor cells of host thymocytes and splenocytes following ICC was demonstrated in a Winn assay. The production of a mainly T-cell-dependent immune response could be due to ICC-induced antigenic changes in the tumor cells.

The effects of fibre in a pelleted diet on food intake, digestibility of crude fibre, dry matter and energy, on passage time and consistency of faeces were studied in 2 species of Callithricidae, Callithrix jacchus and Saguinus fuscicollis. Coarse cellulose, microcellulose, wheat bran and shrimp meal (chitin = crude fibre) were tested in diets containing 2, 4 and 6% total crude fibre, respectively. Digestibility and passage time were determined by inclusion of 0·5% Cr2O3 in the diet. Both celluloses had little influence on the digestibility of energy and dry matter. Digestibility of crude fibre was very low. Wheat bran led to evident depression of energy and dry matter digestibility. High digestibility of crude fibre occurred at the higher levels of inclusion in the diet. Shrimp meal was highly digested with little influence on digestibility of energy and dry matter, indicating considerable degradation of chitin. Wheat bran showed a marked effect, while microcellulose had no effect on passage time, consistency and volume of faeces.