Effects of a caspase and a calpain inhibitor on resting energy expenditures in normal and hypermetabolic rats: a pilot study.

Several diseases induce hypermetabolism, which is characterized by increases in resting energy expenditures (REE) and whole body protein loss. Exaggerated protein degradation is thought to be the driving force underlying this response. The effects of caspase and calpain inhibitors on REE in physiological and hypermetabolic conditions, however, are unknown. Thus, we studied whether MDL28170 (calpain inhibitor) or z-VAD-fmk (caspase inhibitor) affect REE under physiological conditions and during hypermetabolism post-burn. Rats were treated five times weekly and observed for 6 weeks. Treatment was started 2 h (early) or 48 h (late) after burn. In normal rats, MDL28170 transiently increased REE to 130 % of normal during week 2-4. z-VAD-fmk reduced REE by 20-25 % throughout the observation period. Within 14 days after burns, REE increased to 130+/-5 %. Whereas MDL28170/early treatment did not affect REE, MDL28170/late transiently increased REE to 180+/-10 % of normal by week 4 post-burn. In contrast, with z-VAD-fmk/early REE remained between 90-110 % of normal post-burn. z-VAD-fmk/late did not affect burn-induced increases in REE. These data suggest that caspase cascades contribute to the development of hypermetabolism and that burn-induced hypermetabolism can be pharmacologically modulated. Our data point towards caspase cascades as possible therapeutic targets to attenuate hypermetabolism after burns, and possibly in other catabolic disease processes.

Detection and possible role of proteasomes in the bronchoalveolar space of the injured lung.

Recent observations suggest the presence of 20S proteasomes (20S) in the lung epithelial lining fluid. However, the physiological relevance of 20S in the alveolar space and possible contribution to disease processes are unknown. Thus, we evaluated whether extracellular proteasomes could have a pathophysiological role in the injured lung using a rat model of lung contusion (LC). Bronchoalveolar lavage fluids (BALF) were obtained at various time points for up to 168 h after LC or sham procedure. Enzyme activities, ELISA and Western blots indicated enzymatically active 20S, the 19S subunit Rpt5 and ubiquitin in BALF. 20S and ubiquitin increased significantly after LC, peaked at 24 h and normalized within 168 h. Mg(2+)/ATP-dependent peptidase activities were detectable 6-24 h after LC. BALF after LC also contained ubiquitin-protein-ligase activity. Addition of Mg(2+)/ATP to BALF after LC led to significant proteolysis and could be prevented with epoxomicin and EDTA. These data suggest for the first time that the Mg(2+)/ATP-dependent 26S proteasome complex exists outside the cell, is released into the lung epithelial lining fluid after LC and contributes to the proteolysis of the bulk of protein in the alveolar space of the injured lung. We infer that proteasome complexes may have a pathophysiological role during lung edema clearance.

Tumor necrosis factor-alpha production in whole blood after cardiopulmonary bypass: downregulation caused by circulating cytokine-inhibitory activities.

OBJECTIVES: Cardiopulmonary bypass is associated with the release of proinflammatory cytokines (tumor necrosis factor alpha, interleukin 1beta, interleukin 6, and interleukin 8) and anti-inflammatory cytokines (interleukin 10 and transforming growth factor beta(1)). On the one hand this cytokine release is related to the postoperative systemic inflammatory response syndrome, and on the other hand it is related to deterioration of the immune system, for example in monocyte or polymorphonuclear neutrophil function, leading to an increased susceptibility to infections. To gain further insight into the alterations of immune cell reactivity and possible regulatory mechanisms, we studied lipopolysaccharide-induced tumor necrosis factor alpha synthesis in whole blood from cardiac surgical patients. METHODS: Fifteen patients undergoing elective heart surgery with cardiopulmonary bypass were included in the study. Ex vivo lipopolysaccharide-induced tumor necrosis factor alpha synthesis was measured in a whole blood assay before, during, and after bypass. Corresponding tumor necrosis factor alpha messenger RNA levels were determined by semiquantitative reverse transcriptase-polymerase chain reaction. In addition, the influence of patient serum on whole blood responsiveness and its relationship to anti-inflammatory cytokines were evaluated in vitro. RESULTS: Tumor necrosis factor alpha synthesis was significantly reduced after 30 minutes of cardiopulmonary bypass and showed the lowest values at the end of bypass (mean +/- SD 0.109 +/- 0.105 ng/10(6) white blood cells after 30 minutes of bypass and 0.050 +/- 0.065 ng/10(6) white blood cells at the end of bypass, vs 0.450 +/- 0.159 ng/10(6) white blood cells preoperatively, P <.001). As a further indication of reduced cytokine biosynthesis, diminished messenger RNA levels for tumor necrosis factor alpha were detected. Serum withdrawn from patients at the end of cardiopulmonary bypass reduced tumor necrosis factor alpha synthesis in heterologous blood from healthy volunteers highly significantly to 39.93% +/- 23.18% relative to control serum (P =.005) and preoperatively drawn serum (P =.024). This effect was dose dependent and was not specific for lipopolysaccharide-induced tumor necrosis factor alpha synthesis. Anesthesia and heparin administration did not influence tumor necrosis factor alpha production significantly. Ex vivo tumor necrosis factor alpha synthesis was negatively related to interleukin 10 serum levels, positively but weakly related to interleukin 4, and was not related to transforming growth factor beta(1) (Spearman correlation coefficients -0.565, P <.001, 0.362, P <.001, and -0.062, P =.460, respectively). However, interleukin 10 levels in patient serum after cardiopulmonary bypass were 300-fold below the quantities needed for half-maximal inhibition of tumor necrosis factor alpha synthesis in vitro. Moreover, the inhibitory activity could not be removed by immune absorption of interleukin 10. CONCLUSIONS: These results suggest that during cardiac operations cytokine-inhibitory serum activities are released or newly formed. These activities could not be explained by the actions of interleukins 4 and 10 or transforming growth factor beta(1). Although their exact nature remains undetermined, these substances may contribute to the diminished immune cell functions after cardiopulmonary bypass and thus need further characterization.

Laparoscopic splenopexy by peritoneal and omental pouch construction for intermittent splenic torsion ("wandering spleen").

Wandering spleen is an extremely rare anatomic variant with potentially serious clinical implications. Usually, splenectomy is advocated for treatment of this disease. Various methods for preserving the wandering spleen by means of splenopexy have been described, including two reports on laparoscopic splenic refixation. We describe the third case in which laparoscopic splenopexy was used to manage chronic intermittent splenic torsion. In a 25-year-old woman, splenopexy was successfully performed by laparoscopic reposition and fixation of the spleen by omental pouch creation. At laparoscopy with a normal operating room setup and four trocars, a free-floating, macroscopically normal spleen attached to an abnormally long vascular pedicle with no gastrosplenic or phrenicosplenic ligaments was detected in the lower right quadrant. The spleen was repositioned and placed in the left phrenorenal angle. Splenopexy was achieved by suturing the left colophrenic ligament to the lateral diaphragm, thus creating a pouch for the inferior part of the spleen, and by suturing the gastrocolic ligament to the anterior diaphragm to create a pouch for the upper splenic pole. The postoperative course was uneventful. At a follow-up examination 3 months after the operation, the patient was well, with no further episode of recurrent abdominal pain. Ultrasonographically, the spleen was seen easily in the left hypochondrium in its normal physiologic position. Laparoscopic splenopexy is a useful option for organ-preserving therapy of the wandering spleen.

Whole blood tumor necrosis factor-alpha production and its relation to systemic concentrations of interleukin 4, interleukin 10, and transforming growth factor-beta1 in multiply injured blunt trauma victims.

OBJECTIVE: To study the relation of whole blood endotoxin responsiveness to inhibitory mediators systemically released after severe blunt trauma. DESIGN: Prospective, observational study. SETTING: University trauma center. PATIENTS: Thirty-two patients with blunt trauma (mean injury severity score, 33 points). INTERVENTIONS: Standard emergency department, surgical care, and postoperative intensive care unit treatment. MEASUREMENTS AND MAIN RESULTS: Whole blood and serum were obtained immediately after admission to the emergency department (<8 hrs after trauma, denoted day 0) and on days 1, 2, 4, 6, 8, and 14 after trauma. Whole blood specimens were assayed for endotoxin-induced tumor necrosis factor (TNF)-alpha synthesis ex vivo and serum specimen were assayed for interleukin (IL)-4, IL-10, and transforming growth factor (TGF)-beta1 concentrations. Moreover, the TNF-alpha inhibitory capacity of recombinant human (rh) IL-4, rhIL-10, and TGF-beta1 as well as the inhibitory capacity of patients' serum from days 0, 1, 2, 4, 6, 8, and 14 were tested on uninjured donors' whole blood. Cytokines were determined by ELISA. Whole blood endotoxin responsiveness in multiply injured patients was significantly reduced during the observation period and was found to be significantly related to the total inhibitory activity detected in the corresponding sera. Exchange of patients' serum for uninjured donors' or recovered patients' serum restored TNF-alpha production of peripheral blood mononuclear cells from multiply injured patients. Serum levels of IL-4 and IL-10 were not related to trauma patients' whole blood TNF-alpha production upon endotoxin stimulation, whereas TGF-beta1 concentrations were positively related. Compared with the apparent half-maximal inhibition concentrations determined, serum levels of TGF-beta1, IL-10, and IL-4 were 20- to 20,000-fold below the quantities required to explain the inhibitory serum activity in multiply injured patients on day 0. CONCLUSIONS: Whole blood hyporesponsiveness to endotoxin in multiply injured patients is caused by soluble serum factors systemically released after trauma, whereas the intrinsic leukocyte function appears unaffected. Inhibitory mediators other than IL-4, IL-10, or TGF-beta1 are supposed to be of major biological relevance for the posttraumatic regulation of leukocyte function. Characterization of the causative suppressive mediators is supposed as a prerequisite for the development of immunologically based therapeutic approaches in critically ill patients.

Sex differences in posttraumatic cytokine release of endotoxin-stimulated whole blood: relationship to the development of severe sepsis.

BACKGROUND: In experimental trauma-hemorrhage and sepsis, a sexual dimorphism of cell-mediated immune functions has been described, which has been related to higher susceptibility to and mortality from sepsis in males. Therefore, in the present study, sex differences with regard to cytokine release of endotoxin stimulated whole blood and its relation to the development of severe posttraumatic sepsis were investigated in blunt trauma patients with multiple injuries. METHODS: Eighty-four patients (25 female; 59 male) sustaining blunt injuries with an Injury Severity Score > 16 were enrolled in the study. Whole blood and serum were obtained during a 14-day period of hospitalization. The capacity of peripheral blood mononuclear cells to produce cytokines (tumor necrosis factor-alpha, interleukin [IL]-6, IL-8) was tested by using a whole blood assay. Serum samples were assayed for anti-inflammatory cytokines (IL-4, IL-10, and transforming growth factor beta1) and sex hormones (testosterone, estradiol, progesterone). Patients were monitored daily for sepsis criteria according to the ACCP/ SCCM consensus conference 1992. RESULTS: Within the entire patient population, sex differences in posttraumatic cytokine release were not detectable. Male trauma patients developing severe sepsis (n = 16) presented with a significantly increased cytokine producing capacity in the early posttraumatic period (< or = 24 hours after admission to the emergency room) when compared with males with an uncomplicated recovery. In females, differences between the subgroups of patients with (n = 7) and without development of severe sepsis were not detectable. There were no differences in systemic levels of anti-inflammatory cytokines within the early posttraumatic period between the subgroups of male and female patients with and without development of severe sepsis. In females, differences in sex hormone levels were not detectable, whereas in males, development of severe sepsis later was found to coincide with significantly decreased testosterone and increased estradiol serum levels. CONCLUSION: The present study demonstrates a sex-specific regulation of leukocyte function in patients with multiple injuries within the early posttraumatic period. In male patients with multiple injuries, increased cytokine-producing capacities may correspond to enhanced inflammatory responses, which increase susceptibility to sepsis, whereas in female patients, other regulatory mechanisms may be involved.

Cytosolic protein ubiquitylation in normal and endotoxin stimulated human peripheral blood mononuclear cells.

The ubiquitin-proteasome pathway is regarded as playing a crucial role in protein breakdown in inflammation and sepsis as well as in the regulation of inflammatory cell responses. In this pathway, ubiquitylation of target proteins is believed to act as a recognition signal for degradation by the 26S proteasome. As yet neither the ubiquitylation rate of cytosolic proteins, as a result of the total ubiquitin-protein ligase (tUbPL) activity, nor the specific ubiquitylation of calmodulin (ubiquitin-calmodulin ligase, uCaM-synthetase) has been determined in human mononuclear cells. Therefore, we studied cytosolic protein ubiquitylation in normal and in endotoxin (LPS)-stimulated human peripheral blood mononuclear cells (PBMNCs).PBMNCs from healthy volunteers were incubated with 0 or 100 ng/ml LPS for 18 h. Cytosolic extracts were obtained by hypotonic lysis and ultracentrifugation. TUbPL was measured as [(125)I]-[CT]-ubiquitin incorporation into the sum of cytosolic proteins. UCaM-synthetase activity was quantified with the fluphenazine (FP)-Sepharose affinity adsorption test. Endotoxin stimulation appears to inhibit tUbPL 3.7 +/- 2.7-fold to 48 +/- 43 fkat/mg (n = 6). UCaM-synthetase in cultures (n = 5) without endotoxin was determined to be 91 +/- 32 fkat/mg +Ca(2+) and 29 +/- 23 fkat/mg -Ca(2+). With endotoxin uCaM-synthetase was 138 +/- 73 fkat/mg +Ca(2+) and 14 +/- 22 fkat/mg -Ca(2+). Ca(2+)-specificity (ratio +/- Ca(2+)) of uCaM-synthetase increases from 3.1 without LPS to 10 after LPS stimulation, which was caused by a 2-fold decrease in minus Ca(2+) activity and a 1.5-fold increase in plus Ca(2+) activity. The data indicate specific regulatory effects of endotoxin on the cytosolic ubiquitylation systems in human PBMNCs.

Influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) on whole blood endotoxin responsiveness following trauma, cardiopulmonary bypass, and severe sepsis.

Major surgery, multiple injury, and severe sepsis lead to an impaired immune response. The suppressed status of the immune system is reflected by a reduced TNFalpha production of whole blood after stimulation with endotoxin in vitro and by a decreased HLA-DR expression on monocytes. In the present study, the effect of the immunostimulating hematopoetic growth factor GM-CSF on whole blood cultures of multiple injury, cardiac surgery, and severe sepsis patients was investigated. Endotoxin-induced TNFalpha production and HLA-DR expression was reduced in blood cultures of these patients compared to healthy donors. Preincubation with GM-CSF in vitro increased cytokine production in volunteers' and all patients' blood specimens in a dose-dependent manner. The elevation of cytokine response in cardiopulmonary bypass patients' blood, caused by in vitro preincubation with GM-CSF, equaled that of normal patients, whereas GM-CSF caused a lower rise of TNFalpha-producing capacity in blood of multiple-injury and sepsis patients. Further, GM-CSF treatment in vitro increased the down-regulated HLA-DR expression on monocytes prepared after cardiac surgery to a degree comparable to preoperative levels. Finally, GM-CSF incubation in vitro elevated TNFalpha synthesis in normal monocytes and in cells treated with a combination of the anti-inflammatory mediators IL-10, TGFbeta, and PGE2. These experiments show that hyporesponsiveness of whole blood induced by trauma, sepsis, or cardiac surgery is not irreversible but can be, at least in vitro, overridden by the immunostimulating compound GM-CSF.

Relation of a TNF gene polymorphism to severe sepsis in trauma patients.

OBJECTIVE: To investigate the relation of the biallelic Nco1 restriction fragment length polymorphism in the first intron of the tumor necrosis factor (TNF) beta gene with the development of severe sepsis in multiply injured patients. SUMMARY BACKGROUND DATA: The biallelic Nco1 polymorphism of the TNFbeta gene has been described to be associated with autoimmune diseases and with the mortality rate in severe sepsis. Therefore, the Nco1 polymorphism may be associated with the clinical finding that despite comparable risk factors, posttraumatic sepsis develops in some patients but not others. METHODS: The study group consisted of 110 patients with severe blunt trauma (Injury Severity Score > or = 17). Typing of each patient for the biallelic Nco1 polymorphism was performed by analyzing restriction fragments of an Nco1-digested DNA fragment obtained using polymerase chain reaction. Genotypes were then related to the occurrence of severe posttraumatic sepsis and TNFalpha serum concentrations. RESULTS: Fifty-seven patients showed an uncomplicated posttraumatic recovery, and severe sepsis developed in 53 patients. The overall allele frequency (TNFB1 0.29, TNFB2 0.71) and genotype distribution (TNFB1 homozygous 7.3%, TNFB1/TNFB2 42.7%, TNFB2 homozygous 50%) were in agreement with the distribution in healthy volunteers. Genotype distribution in patients with an uncomplicated clinical course was significantly different from that in patients with severe posttraumatic sepsis. Development of severe posttraumatic sepsis was significantly increased in patients homozygous for the allele TNFB2. In patients with severe posttraumatic sepsis, TNFalpha serum concentrations were significantly higher in TNFB2-homozygous individuals compared with heterozygous and TNFB1 -homozygous individuals. The age- and injury-matched odds ratio for the homozygous TNFB2 genotype compared with the heterozygous genotype was 5.22 (p = 0.007, 95% confidence interval 1.6 to 17.9). CONCLUSIONS: In multiply injured patients, the Nco1 polymorphism within the TNFbeta gene is associated with the development of severe posttraumatic sepsis and with increased TNFalpha serum levels when severe sepsis has occurred. This suggests a genetic determination of the individual inflammatory response after infection or tissue damage, which significantly influences susceptibility to severe nosocomial infections.

Relation of ex vivo stimulated blood cytokine synthesis to post-traumatic sepsis.

The cytokine production in endotoxin stimulated blood of patients immediately after polytrauma with high risk for developing sepsis or multi organ failure was analysed. Forty patients sustaining traumatic injury with >/=317 pts according to the Injury Severity Score (ISS), 10 of whom developed severe sepsis (ACCP/SCCM conference 1992) were included in the study. Levels of interleukin 8 (IL-8), IL-6 and tumour necrosis factor (TNF) were measured by ELISA in endotoxin-stimulated whole blood and IL-10 and IL-6 in serum. The allotype for the bi-allelic Nco I restriction length polymorphism in the TNF locus was determined for each patient.Two to four hours after polytrauma endotoxin-stimulated synthesis of TNF and IL-6 was found to be reduced in whole blood from patients compared to healthy donors, whereas no such differences were found for IL-8 synthesis. At this time, however, the patients who developed sepsis at a later stage (day 4-6) showed significantly (P<0.05) enhanced IL-8 synthesis in endotoxin stimulated whole blood in comparison to healthy donors. The IL-6 and TNF production of their blood was significantly enhanced compared to patients with uncomplicated recovery. Ninety per cent of the patients developing sepsis were of the TNFB2/TNFB2 allotype, whereas this was the case for only 30% of the non-septic group. Assessment of endotoxin-stimulated cytokine synthesis may provide a prognostic indicator for patients at high risk for developing a sepsis syndrome.

The extent of traumatic damage determines a graded depression of the endotoxin responsiveness of peripheral blood mononuclear cells from patients with blunt injuries.

OBJECTIVE: To study whether the endotoxin responsiveness of peripheral blood mononuclear cells correlates with the severity of injury in trauma patients. DESIGN: Prospective, observational study. SETTING: University trauma center. PATIENTS: Fifty-nine patients with blunt trauma (Injury Severity Score [ISS] 4 to 57 points). INTERVENTIONS: Standard emergency department care, surgical care, and postoperative intensive care unit treatment. MEASUREMENTS AND MAIN RESULTS: Whole blood and serum were obtained 94+/-89 (SD) mins post trauma (day 0) and during a 14-day period postinjury. Endotoxin-induced tumor necrosis factor-alpha (TNF-alpha) synthesis of peripheral blood mononuclear cells ex vivo was tested using a whole blood assay. Serum samples were assayed for TNF-alpha concentrations. A reduced capacity of whole blood to produce TNF-alpha ex vivo with endotoxin treatment was found to be closely correlated with the ISS. The capacity to produce TNF-alpha on endotoxin stimulation of whole blood from patients with an ISS > or =16 points was depressed immediately after trauma and did not reach normal values during the observation period. In patients with an ISS >22 points, maximum depression of the capacity of whole blood to produce TNF-alpha occurs within 100 mins post injury. In contrast, in patients with an ISS <22 points, maximal depression of whole blood TNF-alpha production occurs with a delay of 24 to 48 hrs after trauma. Based on pre- and postoperative values, primary surgical intervention caused a decrease of the endotoxin-stimulated TNF-alpha production of whole blood in the latter patient subgroup, as well as in the entire patient population (ISS 4 to 57) when secondary surgical treatment was necessary 5 to 13 days after trauma. CONCLUSIONS: The extent of traumatic tissue damage leads to a graded depression of immunocyte function and appears to be amplified by surgical treatment. The endotoxin responsiveness of peripheral blood mononuclear cells displays a functional marker of the anatomically defined severity of injury and gives insights into the regulation of immunocyte function after severe blunt trauma.

HLA-DR expression and soluble HLA-DR levels in septic patients after trauma.

OBJECTIVE: To determine if cellular and soluble HLA-DR molecules may be relevant in severely injured patients for the development of gram-positive or gram-negative sepsis. SUMMARY BACKGROUND DATA: HLA-DR molecules play a central role in the specific immune response to infection. The reduced HLA-DR expression on monocytes is considered to correlate with infectious complications and the development of sepsis. Data on the role of HLA-DR expression on T cells and soluble HLA-DR molecules are rare. METHODS: HLA-DR expression on monocytes and T cells was measured by flow cytometry. Plasma levels of soluble HLA-DR were studied by enzyme-linked immunosorbent assay. RESULTS: HLA-DR expression on circulating T cells, calculated as mean fluorescence intensity in channels, was reduced at day 1 after admission in 20 patients with subsequent severe sepsis compared with 46 patients without sepsis. The septic patients immediately after trauma had significantly lower soluble HLA-DR plasma levels than the nonseptic patients. At day 2 after admission, HLA-DR expression on monocytes was significantly lower in the severe sepsis group than in the patients without sepsis, and lasted until day 14 after injury. CONCLUSIONS: In severely injured patients, decreased levels of cellular and soluble HLA-DR appear as early indicators of an immune deviation associated with the development of severe sepsis. Moreover, immune alterations of different cell types may promote distinct kinds of septicemia.

Relation of the bi-allelic NcoI restriction fragment length polymorphism within the tumour necrosis factor B gene to the development of mediastinitis.

During recent years the dual role of endogenous inflammatory mediators such as tumour necrosis factor (TNF) has become evident. While TNF has been recognised to possess a great detrimental potential, for example in the case of sepsis, it is on the other hand an integral component of an adequate immune response to bacterial invasion. These different properties of TNF and others seem to be dependent mainly on the quantitative extent of their formation. Some recent findings indicate that this extent may in part be determined genetically. The classification of patients according to polymorphic cytokine genes might, therefore, predict some of their reactions to septic challenges.

Reduced B cell HLA-DR expression and natural killer cell counts in patients prone to sepsis after injury.

OBJECTIVE: To examine the influence of natural killer (NK) cells and HLA-DR molecules on B cells in the development of severe sepsis after injury. DESIGN: Prospective study. SETTING: Medical school, Germany. SUBJECTS: 46 severely injured (Injury Severity Score >16) patients. INTERVENTIONS: Blood samples were taken immediately after admission and subsequently for 14 days. MAIN OUTCOME MEASURES: HLA-DR expression on B cells and counts of B and NK cells measured by flow cytometry, and morphological estimation of large granular lymphocytes by microscopy. RESULTS: HLA-DR expression on circulating B cells was significantly reduced from days 6-14 after admission in 13 patients with subsequent severe sepsis compared with 33 patients who did not develop sepsis. In septic patients NK cell counts were significantly decreased from day 4 onwards (p < 0.05). CD16+/CD56+ cells correlated with the morphology of large granular lymphocytes. CONCLUSION: In severely injured patients reduced counts of NK cells and HLA-DR molecules on B lymphocytes seem to be part of an immune deviation that is associated with the development of severe sepsis.

Local and systemic reactions after lung contusion: an experimental study in the pig.

The present study was designed to investigate the consequences of isolated unilateral lung contusion on local alveolar and systemic inflammatory responses in an animal model in the pig. Isolated unilateral lung contusion was induced by bolt shot in eight mechanically ventilated animals under general anesthesia (sham: n=4). Plasma and bronchoalveolar lavage fluid were collected during a period of 8 h following lung contusion. Leukocytes, leukocyte neutral protease inhibitor (LNPI), terminal complement complex (TCC), thrombin-antithrombin-complex (TAT) as well as pulmonary microvascular permeability and surfactant function were determined. Within 30 min, lung contusion was found to cause a significant local and systemic increase in TCC and TAT concentrations and a systemic increase in LNPI concentrations. The latter was accompanied by a sequestration of leukocytes in the contused lung. Complement activation and leukocyte sequestration in the contused lung progressively increased during the investigation period. Although surfactant function decreased in the entire lung 30 min after contusion, TCC, TAT, and leukocyte sequestration was unchanged in the contralateral lung. The first indication of an involvement of the contralateral lung was obtained by an increase in leukocyte sequestration 8 h after lung contusion. Unilateral lung contusion initiates an early systemic activation of humoral and cellular defense systems. Involvement of the contralateral lung appears to be a secondary event caused by a systemic inflammatory reaction.

[Modification of immune response after polytrauma and cardiopulmonary bypass by hematopoietic growth factors]. / Beeinflussung der Immunantwort nach Polytrauma und cardiopulmonalem Bypass durch hämatopoetische Wachstumsfaktoren.

Cardiac surgery and polytrauma result in an impaired immune response as it can be demonstrated by a reduced endotoxin-stimulated TNF alpha production of whole blood cultures ex vivo. The immune-stimulating hematopoetic growth factor GM-CSF is in vitro capable to antagonize the suppressed immune function after trauma and cardiac surgery and, therefore, GM-CSF represents a potential therapeutic for immune suppressed states.

Estimation of condensed pulmonary parenchyma from gas exchange parameters in patients with multiple trauma and blunt chest trauma.

Pulmonary gas exchange in correlation with condensed lung volume was prospectively studied in 10 patients with multiple injuries and blunt chest trauma. The purpose was to find nomograms that allow the estimation of the extent of pulmonary density from gas exchange parameters. The condensed lung volume was determined planimetrically from serial transverse sections of chest computed tomographic scans. There was no correlation between condensed lung volume and mean pulmonary artery pressure, pulmonary vascular resistance, systemic vascular resistance, or cardiac index and a week negative correlation to the oxygenation index (PaO2/FIO2) (r2 = 0.46) and to the total static lung compliance (r2 = 0.29). A strong correlation between pulmonary density and intrapulmonary shunt fraction (Qs/Qt) (r2 = 0.95) as well as alveoloarterial PO2 difference (P[A-a]O2) (r2 = 0.86) was evident. By using linear regression equations (linear regression line with 95% confidence interval), nomograms were calculated. The extent of pulmonary density can easily be obtained from these nomograms by measuring Qs/Qt or P(A-a)O2. The presented nomograms may be helpful in monitoring the effect of treatment in patients with blunt chest trauma.

Regulation of whole blood tumor necrosis factor production upon endotoxin stimulation after severe blunt trauma.

BACKGROUND: Trauma has been recognized to be accompanied by alterations of leukocyte functions such as cytokine release. The regulatory principles involved in these changes are still poorly defined. To further characterize leukocyte function after multiple trauma, endotoxin-stimulated tumor necrosis factor (TNF) production of trauma patients' whole blood and a possible regulatory mechanism were studied. METHODS: Endotoxin responsiveness in trauma patients (n = 18, Injury Severity Score = 24 +/- 7) was assayed ex vivo using a whole blood model. TNF release and TNFalpha mRNA levels were determined during a 14-day period. Furthermore, the influence of patients' sera on whole blood TNF production was evaluated. MAIN RESULTS: The capacity of trauma patients' whole blood to produce TNF was reduced for 2 to 6 days after trauma and was equally evident for both TNF release and TNFalpha mRNA levels. The reduction of TNF coincides with the appearance of an inhibitory activity for TNF production in trauma patients' sera. No correlation was found between the inhibitory activity and soluble TNF receptors, endotoxin-neutralizing molecules, inhibitory cytokines (interleukin 10 and transforming growth factor beta), or prostaglandins. CONCLUSIONS: Major trauma leads to the appearance of a circulating inhibitory activity for TNF synthesis that may potentially contribute to an anti-inflammatory response in patients with multiple trauma. The elucidation of its structural and functional properties may contribute to the understanding of the pathogenesis of severely injured patients.