|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 |
ABSTRACT |
|---|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
The balance between proinflammatory cytokines and their inhibitors has rarely been investigated in
pleural effusions of nonmalignant or noninfectious origin. To evaluate the impact of a lung and/or intrathoracic infection in such a circumstance, we compared the levels of proinflammatory cytokines
(interleukin-8 [IL-8]); tumor necrosis factor-
(TNF-); the cytokine antagonists and inhibitors (IL-1
receptor antagonist [IL-1ra] ) and soluble TNF receptors Types I and II (sTNFRI, sTNFRII); and antiinflammatory cytokines (transforming growth factor-
[TGF-]) in pleural effusion and plasma from
septic (n = 15) and nonseptic (n = 9) patients. In addition, we analyzed the levels of IL-6 and its soluble receptor (sIL-6R). Bronchoalveolar lavage fluids (BALFs) were also studied in a few septic patients. High and nonsignificantly different levels of cytokines and inhibitors were detected in both
groups of patients. The levels of IL-6 and sTNFRI and sTNFRII in pleural effusion were higher than in
plasma, whereas the levels of IL-1ra and sIL-6R were higher in plasma. The levels of sIL-6R influenced the bioactivity of IL-6. There was no correlation between the levels of cytokines in plasma and in
pleural effusion. In contrast, a significant correlation was observed for the soluble receptors sIL-6R
(r = 0.67, p < 0.001), sTNFRI (r = 0.76, p < 0.001) and sTNFRII (r = 0.66, p = 0.001). Furthermore, a
high correlation was found between the levels of both forms of sTNFRs in plasma (r = 0.95, p < 0.001) and in pleural effusion (r = 0.79, p < 0.001). In addition, a correlation was observed between
the levels of TGF- in pleural effusion and in BALF. The highest levels of some markers in plasma and
of others in pleura argue in favor of both a systemic and a compartmentalized response, independently of the presence of infection. Because cytokines can be trapped by the surrounding cells in
their environment, measurable levels of cytokines in biologic fluids represent the "tip of the iceberg," which is not the case for soluble receptors. The correlations of these latter markers between plasma
and pleura strongly suggest that exchanges between both compartments can occur in both directions.
| |
INTRODUCTION |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Since the initial description of acute respiratory distress syndrome (ARDS), the definition of this condition has been revisited (1) and extended to the concept of acute lung injury (ALI). On this basis, efforts are made to clarify such a syndrome, at least in terms of causal diseases, as infectious or noninfectious (2). It also appears clear that primary injury to the lung has a better prognosis than secondary insult of the lung as part of multiple organ failure (3). Such observations might have pathophysiologic bases, especially in the case of inflammation, which can be more or less compartmentalized (4).
Characterization of inflammation of the lungs has received attention for many years, but with controversial results in relation to the causes of ALI, the time of collection of fluid samples in the course of the disease, the types of inflammatory mediators studied, and the methods used for measuring the concentrations of these mediators. Most of the previously obtained results have involved blood and bronchoalveolar lavage fluid (BALF). The latter has some limitations, since it is an artificial fluid, posing difficulty in interpreting the measured concentrations of its solutes, and largely reflects limited areas of the injured lung. This may have important consequences, since cytokine levels depend on the presence or lack of regional inflammation.
Pulmonary inflammation and infection are associated with a local activation of environmental tissues and recruited inflammatory cells. This compartmentalized response has been analyzed with human bronchoalveolar lavage (BAL). The presence of inflammatory cytokines in BALF has particularly been studied, and local levels of cytokines have often been found to correlate with the severity of the pathology or outcome (5). Human pleural space is another site on which analysis can be performed. Furthermore, pleural effusion constitutes a naturally occurring physiologic inflammatory exudate. Cytokine-producing cells and cytokines have been reported in pleural effusion from patients with malignant pleurisy, tuberculosis, and empyema (8). Recruited leukocytes (12, 13), as well as pleural mesothelial cells (18, 19), can contribute to the local production of cytokines. In addition to a local response, many pulmonary pathologies are associated with a systemic inflammatory response that can be monitored by measuring circulating cytokines (5, 20). However, levels of pleural cytokines have rarely been compared with their plasma levels. Transudation of plasma proteins into inflammatory sites is a well known phenomenon, whereas little is known about the possible exchanges of locally produced or released inflammatory agents with the bloodstream, either directly or via the lymphatic route.
Inflammation implies a complex balance between pro- and
antiinflammatory mediators. The present study was designed
to: (1) characterize the pro- and antiinflammatory cytokine profile in different liquid compartments surrounding the acutely
injured lung; (2) evaluate the impact of a lung and/or intrathoracic infection in such a profile; and (3) clarify the potential
clinical interest in analyzing pleural fluid. We measured and
compared levels of proinflammatory cytokines (interleukin-8
[IL-8]), tumor necrosis factor- (TNF-), the cytokine antagonists and inhibitors (IL-1 receptor antagonist [IL-1ra]) and
soluble TNF receptors Types I and II (sTNFRI and sTNFRII);
and antiinflammatory cytokines (transforming growth factor-
[TGF-]) in pleural effusion and plasma from septic and nonseptic patients. In addition, we analyzed the levels of IL-6 and
its soluble receptor (sIL-6R). IL-6 is a major marker of the systemic response to the inflammatory process, owing to its capacity to induce the synthesis of acute-phase proteins, and sIL-6R
plays an amplifying role and contributes to enhancing the bioactivity of IL-6 (21).
| |
METHODS |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Patients
The study was approved by the hospital ethical committee. Twenty-four patients, ranging from 24 to 86 yr of age (50 ± 16 yr, mean ± SD), were included in the study when a pleural effusion was diagnosed upon chest X-ray and/or computed tomographic (CT) scan. Because of the interest focused on pleural effusion in this study, the description of the intrathoracic injury causing effusion is crucial to analyzing inflammatory parameters. Two groups of patients were identified a posteriori according to a septic or nonseptic cause of underlying acute pulmonary injury with pleural effusion. The criteria for diagnosis of a septic context was a temperature > 38° C or < 35° C and a systolic blood pressure < 90 mm Hg, both being present for a minimum of 2 h, along with a clinically identifiable source of thoracic infection. The subsequent strategies for diagnosing pneumonia ranged from a clinical approach to invasive microbiologic techniques, with investigation of new onset of fever, purulent sputum, leukocytosis, new lung infiltrates, and protected directed fibroscopic sampling to obtain lower-respiratory-tract secretions. Bacterial growth in these specimens was quantified, and the presence of pneumonia and identity of the etiologic pathogens were defined by the recovery of bacteria at counts above 104 to 105 cfu/ml (22). When such clinical and bacteriologic criteria were absent in the absence of any other localization of infection, patients were considered nonseptic. In this case, pleural effusion resulted from another cause of inflammation or from a noninflammatory mechanism. Patient 6, who had a documented mediastinitis without pneumonia, was included in the septic group.
Blood (n = 24), pleural fluid (n = 24), and BALF (n = 9) samples
were collected at the same time and prepared for subsequent analysis.
BALF analyses were performed with a standard technique as indicated by the severity of the Murray score. BAL, with a fiberoptic
bronchoscope, was performed in areas corresponding to radiologic
opacities by injecting 100 ml of sterile saline solution into a lung subsegment and aspirating each aliquot. The return of the first 10-ml aliquot (bronchial fraction) was discarded. The recovered BALF was
rapidly filtered through sterile gauze. The recovery of the BALF averaged 71 ± 4% of the injected volume. All fluids were centrifuged and
supernatants were aliquoted and stored at 
40° C until analyses were
performed. Aliquots were used to determine the cellularity of each
fluid, followed by May-Grunwald-Giemsa staining and cell characterization. In addition, protein concentrations of sera and pleural fluid
were determined classically. On this basis, the protein-concentration
ratio between pleural fluid and serum was calculated individually to
characterize the exudative mechanism in each case (23).
Cytokines and Soluble-receptor Measurements
TNF-, IL-6, IL-1ra, TGF-, and sIL-6R were assessed with enzyme-linked immunosorbent assay (ELISA) kits from R&D Systems (Abingdon, UK), sTNFRI and sTNFRII were measured with ELISAs
provided by Medgenix (Fleurus, Belgium). In a previous study we had
ensured that soluble receptors and 2-macroglobulin, known to combine with various cytokines, did not interfere in the measurements (24). Spiking experiments gave satisfactory results as long as the recombinant cytokine used was identical to the standard used in the assay (data not shown). Samples, measured in duplicate, were appropriately diluted in phosphate-buffered saline (PBS)-Tween-bovine serum albumin (BSA) buffer to ensure optical density (OD) values within the standard curve.
ELISA specific for IL-8 was performed as previously described and characterized (25). Briefly, Maxisorp microtitration plates (Nunclon, Rockeville, Denmark) were coated with 5 µg/100 µl/well of mouse monoclonal antihuman IL-8 antibody (mAb No. 4) in carbonate buffer (0.05 M, pH 9.6) and kept overnight at 4° C. After washings with PBS-Tween buffer, saturation was achieved by adding 2% BSA in carbonate buffer (100 µl/well) for 1 h at 37° C. The washings were followed by addition of an international standard recombinant IL-8 (National Institute for Biological Standards and Controls, Potters Bar, UK), plasma samples, and pleural fluids diluted in PBS-Tween (0.1%)-BSA (1%), each at 100 µl/well for 2 h at 37° C. After a further washing step, 100 µl of rabbit polyclonal antihuman IL-8 antibody (1:5,000, a generous gift of Dr. N. Vita, Sanofi Recherche, Labège, France) was added to each well. After 1.5 h at 37° C, plates were washed and 100 µl/well of peroxidase-labeled goat antirabbit immunoglobulin (1:2,500; Silenius, Hawthorn, Australia) was added and the wells kept for 1 h at 37° C. After the plates were again washed, enzymatic activity was shown by the addition of 200 µl/well orthophenylene-diamine substrate (1 mg/ml; Sigma Chemical, St. Louis, MO) in citrate buffer (0.05 M, pH 5) containing 0.06% hydrogen peroxide. Plates were kept in darkness and the reaction was stopped by the addition of 50 µl/well HCl 3N. OD was measured at 490 nm on a microplate reader spectrophotometer.
IL-6 Bioassay
IL-6 activity was determined with the specific 7TD1 IL-6-dependent
cell line, kindly provided by Dr. J. Van Snick of the Ludwig Institute
for Cancer Research, Brussels, Belgium. The bioassay was done as
previously described (26). Briefly, cells (1,200/100 µl/well) were cultured in RPMI-1640 supplemented with antibiotics, 2-mercaptoethanol (5 × 10
5 M), and 10% fetal calf serum (FCS) in the presence of
serial dilutions of plasma or pleural fluids. After 4 d of culture at 37° C,
under 95% air/5% CO2 in an incubator, cell proliferation was monitored through staining with 3-[4, 5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). The tetrazolium salt, at 125 µg/25 µl,
was added to each well, and after 1 to 2 h at 37° C the test was stopped with 100 µl of extraction buffer (20% sodium dodecyl sulfate [SDS]); 50% dimethylformamide [DMF] in H2O; 2.5% HCl 1N; and 2.5% acetic acid (80% solution, pH 7.4). After overnight incubation at 37° C,
the absorbance was measured at 540 nm, using an automated microELISA autoreader. One unit of IL-6 corresponds to half the maximum growth rate of the hybridoma cells obtained by adding recombinant human IL-6.
Statistics
Comparisons were made with the Mann-Whitney or Wilcoxon's signed rank tests.
| |
RESULTS |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
Table 1 summarizes the clinical characteristics of the two study groups. Although nonsignificant, the mortality rate related to multiple organ failure was higher in the septic than in the nonseptic group. As expected, the severity of ALI assessed with the adapted Murray score (1) was greater in the septic than in the nonseptic group, although again nonsignificantly. However, the global severity of ALI in these two groups as assessed from the SAPS score was comparable. Positive end-expiratory pressure (PEEP) levels were higher in the septic group, whereas the difference between the two groups in PaO2/ FIO2 ratio did not reach statistical significance.
|
Table 2 shows the characteristics of blood and pleural fluid in the two groups. One can observe that the total pleural/serum protein ratio did not differ in the two groups. Blood cellularity patterns were similar in both groups, but differred for pleural fluid. The polymorphonuclear leukocyte (PMN) fraction was significantly higher in the septic than in the nonseptic group despite negative culture of pleural fluid (with the exception of Patient 12).
|
Table 3 summarizes the individual data for BALFs and indicates a predominant fraction of PMN.
|
As shown in Figure 1, no significant differences were observed between the levels of cytokines and soluble receptors
in pleural effusion from septic and nonseptic critically ill patients. Similarly, there was no difference between the levels of
cytokines and soluble receptors in plasma from septic and
nonseptic patients. Thus, after compiling the data from both
groups, we performed further analyses in which we detected
high levels of IL-6, IL-8, IL-1ra, sTNFRI, sTNFRII, and sIL-6R in pleural effusions. In contrast, low levels of TNF- were
measured (mean ± SEM of n values above detection limit in
plasma = 34 ± 10 pg/ml; n = 17; and in pleural effusion = 26 ± 3 pg/ml; n = 21). There were significant differences between
the levels of measured mediators in plasma and pleural effusion, with the exception of IL-8 and TNF-. Significantly higher levels of IL-6, sTNFRI, and sTNFRII, and significantly lower levels of IL-1ra and sIL-6R, were detected in pleural effusion than in plasma. Consequently, the IL-6/sIL-6R ratios in
plasma and in pleural effusion were greatly different, with median values of 0.005 and 2.1, respectively. No correlation was
found between the Murray score and the levels of any measured factors in pleural effusion.
|
Significant correlations were found between the levels in
plasma and in pleural effusion of both sTNFRI and sTNFRII
(r = 0.76, p < 0.001; and r = 0.66, p = 0.001, respectively)
(Figure 2). Similarly, a significant correlation was observed for
the levels of sIL-6R in plasma and in pleural fluid (r = 0.67;
p < 0.001). There was no correlation between the levels of the
different cytokines and soluble receptors in pleural effusion,
with the exception of sTNFRI and sTNFRII (r = 0.79, p < 0.001), which were also highly correlated in plasma (r = 0.95, p < 0.001) (Figure 2). These correlations were observed independently of the presence or lack of infection. Only in the
group of infected patients was a correlation between levels of
pleural IL-1ra and TGF- also noticed (r = 0.72, p = 0.002).
As shown in Figure 3, TGF- was detectable in pleural effusion (mean = 5,723 ± 849 pg/ml, n = 24), in which levels of this cytokine were lower than in plasma (mean ± SEM = 13,616 ± 2,423, n = 20). Measurements of cytokines and soluble receptors were also performed on BALF of seven septic
patients. When compared with those in pleural effusion, the
levels of all measured factors in BALF were low (IL-1ra = 5.8 ± 2.4 ng/ml; IL-8 = 3.3 ± 2.4 ng/ml; TGF- = 0.6 ± 0.1 ng/ml; IL-6 = 0.3 ± 0.2 ng/ml; sTNFRI = 0.7 ± 0.2 ng/ml;
sTNFRII = 0.5 ± 0.1 ng/ml; sIL-6R = 0.1 ± 0.03 ng/ml; and
TNF- = undetectable). There was a significant correlation between the levels of TGF- in BALF and pleural fluid (r = 0.87, p = 0.01) (Figure 3), a correlation that did not exist between plasma and pleural TGF- levels.
|
|
To analyze whether the IL-6/sIL-6R ratio might influence the bioactivity of IL-6, we tested the capacity of some samples to sustain the proliferation of the IL-6-dependent 7TD1 cell line. We compared different pleural fluid samples that had closely similar levels of IL-6 but various levels of the soluble gp80 receptor. As shown in Table 4, the bioactivity correlated with the levels of sIL-6R. When plasma and pleural samples with similar IL-6 levels were compared, the bioactivities were very close, and again higher in the sample that contained the highest levels of sIL-6R.
|
| |
DISCUSSION |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
ALI in patients under intensive care corresponds to different mechanisms that have been studied mainly with BAL. Despite important limitations, BAL is considered one of the best means for characterizing lung inflammation. Concentrations of various mediators have been measured, and according to the site of inflammation, BAL confirmed the concept of compartmentalization of inflammation (4, 5, 7, 20). Because it is uncertain that the BALF content of alveolar cells and substances reflects their lung-tissue content, especially for the interstitium, it has long been a practice to look at the lymph fluid coming from the lung to characterize the intensity of inflammation in experimental models. Since it is not possible to do this in the clinical setting, it may be interesting to examine the pleural effusion, which depends mainly on lymphatic drainage; another approach to lung-tissue inflammation might then involve study of the pleural fluid.
Pleural effusion signals an abnormal pathophysiologic state that has resulted in a disequilibrium between the formation and removal of pleural fluid. Pleural exudates are caused predominantly by pleural inflammation and impaired lymphatic drainage. In this respect, parapneumonic effusion, at the acute state, has been shown to contain high leukocyte counts and protein concentrations. To our knowledge, no report has been published on pleural exudate composition in term of cells, protein, and pro- and antiinflammatory cytokines in critically ill patients with ALI.
By definition, the population selected for the present study
had pleural effusion that was related to different mechanisms. For 15 out of 24 patients (63%), the mechanism of lung inflammation was related to a documented lung infection with
different microorganisms. For the remaining patients, pleural
effusion was related to heart failure, caustic lung injury, lung
contusion, or massive atelectasis without infection. Although
the classification of infectious and noninfectious lung injury
was based on published criteria for pneumonia, it remains the
most difficult diagnosis in intensive-care-unit (ICU) patients.
In our study the global death rate was 45%, with 30% of
deaths occurring in patients with noninfected lungs and 53%
in patients with infectious pneumonia. The exudative nature of pleural effusion was confirmed in both groups, since the
fluid/serum total protein ratio was 
0.50. The cell composition of pleural fluid differed between the groups, the infected
lungs having a significantly greater proportion of leukocytes
than the noninfected lungs, whereas the blood-cell characteristics of the two groups were similar.
The inflammatory process is characterized by an exacerbated release of proinflammatory cytokines as well as natural cytokine antagonists (e.g., IL-1ra) or the soluble form of cytokine receptors (e.g., sTNFRI and sTNFRII). This, to our knowledge, is the first report on the presence of soluble TNF receptors in pleural effusion.
Increased levels of sTNFRI and sTNFRII were detected in
both plasma and pleural fluid, and levels of sTNFRI and
sTNFRII were higher in pleural effusion than in blood. A significant correlation between levels of the two types of sTNFR
in pleural effusion was noticed independently of the presence
of infection. Such a correlation has already been observed in
the plasma of septic patients (27, 28), and was confirmed in
the present study. Although we did not find any other correlation between the markers we analyzed in pleural fluids, Heymann and colleagues (8) reported some correlations between
the leukemia inhibitory factor, IL-4, and IL-10, depending
on the type of pathology. The presence of sTNFRs in large
amounts in pleural effusion may indicate that their release can
occur locally. It is likely that the compartmentalized presence of cytokines and inhibitors suggests that a particular pleural effusion reflects a locally occurring inflammation. Mesothelial cells are sensitive to TNF- (11), which illustrates that they have TNFRs and may release these receptors either passively
or actively upon activation. Infiltrating leukocytes are other
potential cells that may shed their TNF receptors. We detected very modest levels of TNF- as compared to those reported in tuberculous and empyemic pleural fluids (9, 12). The
high concentrations of sTNFR (sTNFRI: range = 15.4 to 47 ng/ml; mean = 26.7 ± 1.6 ng/ml; and sTNFRII: range = 14.6 to 87.7 ng/ml, mean = 38.8 ± 4.2 ng/ml) as compared with
TNF itself (range = 15 to 75 pg/ml; mean = 26 ± 3 pg/ml) suggest that the antiinflammatory process is occurring locally to
dampen the effects of this proinflammatory cytokine.
The higher concentration of IL-1ra in the circulation as
compared with the levels detected in pleural effusion suggest
that in the group of patients studied, this antagonist corresponds to a systemic antiinflammatory response rather than to
a unique, locally occurring inflammatory process. This finding
with regard to circulating IL-1ra identified it as a circulating
marker of inflammation and sepsis (29). The levels of IL-1ra
we report in pleural effusions are high as compared with those
reported in a recent study of cancer patients (30). Whether the
IL-1ra levels we observed (median = 11 ng/ml) could be sufficient to fully limit the local effects of IL-1 remains to be further addressed. The median levels of IL-1 reported by others
(80 pg/ml in parapneumonic, 60 to 400 pg/ml in tuberculous,
300 pg/ml in carcinomatous, and 380 pg/ml in empyemic pleural effusions) (16, 31) suggest that levels of IL-1ra exceed
those of IL-1 in a sufficient ratio to neutralize the bioactivity
of IL-1.
Although IL-1ra and soluble TNF receptors inhibit the
function of their respective ligands, sIL-6R enhances the properties of IL-6 by increasing its half-life (21). In agreement with recent reports (32, 33), we found lower sIL-6R levels and greater levels of IL-6 in pleural effusion than in plasma. Consequently, the IL-6/sIL-6R ratio in blood is far lower than in
pleural effusion (median = 0.005 versus 2.1, respectively). The
contribution of sIL-6R is most likely less important when IL-6
is acting locally as compared with circulating IL-6, which acts
in an endocrine fashion. One may suggest that IL-6R actively
enhances the bioactivity of its respective cytokine. Accordingly, we demonstrated that samples with similar levels of IL-6
as assessed with ELISA had an IL-6 bioactivity that was significantly influenced by the levels of sIL-6R. The presence of a
high concentration of sIL-6R enhanced the bioactivity of IL-6
in the 7TD1 bioassay. These results suggest that in the studied
samples, soluble gp130 does not play a major regulatory role.
One possible indicator of this is that the levels of soluble
gp130 are very similar from one sample to another (33), and
thus have a limited effect on IL-6 bioactivity. Among local putative sources of IL-6 and sIL-6R, mesothelial cells should be
mentioned, since they can produce IL-6 and are activated in an autocrine fashion by IL-6 (18). In addition to IL-6, other cytokines have been found to be present in greater amounts in pleural fluids than in blood. This is particularly the case for IL-12 (15), TNF- (12), IL-10, and interferon-
(IFN-) (13) in
tuberculous pleural fluids.
The correlations that we found between levels of the different markers in blood and pleural effusion, particularly for
sTNFRI, sTNFRII, and sIL-6R, suggest that the local inflammatory response can communicate with the systemic environment. The high correlation between albumin and C-reactive
protein (CRP) levels in plasma and pleural effusion reported
by Doré and coworkers (33) further supports this suggestion.
Mesothelial permeability has been previously characterized,
and fluid fluxes can occur passively through both the endothelium and the pleural mesothelium. In addition, lymphatic stomata open directly on the parietal pleura and provide a route for liquid and solute clearance under physiologic conditions
(34). Because of significant correlations independent of the locations at which the highest levels could be measured, one
may suggest that the exchange between the two compartments
can occur in both directions. However, the failure to observe
such correlations for IL-8, TNF-, and TGF- is not in keeping with a simple equilibrium between both compartments.
Nevertheless, the cytokines detected in biologic fluids represent only the "tip of the iceberg" (35), particularly because the
cellular environment can efficiently trap these mediators. This
is illustrated by the finding of a very great amount of cell-associated IL-8 when the cells recovered from the pleural effusions in our study were lysed and analyzed for IL-8 (data not
shown). Although soluble cytokine can be well trapped by surrounding cells, this is not the case for soluble receptors. Thus,
the measured levels of soluble receptors most likely represent
the vast majority of released factors, whereas this is not the
case for soluble cytokines.
We did not find any correlation between the levels of cytokines, antagonists, and soluble receptors in pleural effusion
and BALF in the patients in whom these substances were assayed, except for TGF- and sTNFRI (data not shown). This
observation illustrates that correlations between cytokines,
antagonists, and soluble receptors should be interpreted very
cautiously. Either there was an active exchange for these two
specific markers between the pleura and the alveolar space, or
their correlation may reflect a similar response in both compartments as a function of the stressful conditions associated
with the inflammatory and/or infectious processes.
In contrast to other investigators who compared the levels of cytokines in pleural effusion from cancer patients and patients with tuberculosis (31, 32), we did not find a significant difference between the levels of the analyzed markers and the presence of infection. This may be due to the rarity of study of groups of patients without infection. The comparable levels of studied markers in both groups of patients suggest that their production and/or release both systemically and locally occurs independently of microbial stimuli. Most probably, a self-perpetuating cascade of cytokines is involved in these inflammatory processes. The main difference between pleural fluids of septic and nonseptic origin was the nature of infiltrating cells. Greater numbers of neutrophils were detected in patients with infection. However, there was no difference in the levels of IL-8 between the two groups of patients. Thus, the contribution of other chemokines might well explain the observed differences in cellularity.
In conclusion, we have characterized the presence of pro- and antiinflammatory mediators in different compartments surrounding the acutely injured lung, and observed high levels of inhibitors in pleural fluid. We found a correlation between the levels of only a few markers in the different compartments, confirming a complex interchange between pleura, alveolar space, and blood. We have demonstrated the absence of an effect of lung and/or intrathoracic infection on such a profile. In sum, we have illustrated a potential clinical interest in analyzing pleural fluid.
| |
Footnotes |
|---|
Ms. Marie was supported by a Pasteur-Weizman grant.
Correspondence and requests for reprints should be addressed to Dr. J.-M. Cavaillon, Unité d'Immuno-Allergie, Institut Pasteur, 28 rue Dr. Roux, 75015 Paris, France.
(Received in original form February 26, 1997 and in revised form April 29, 1997).
Acknowledgments: The authors thank David Cohen for linguistic advice.
| |
References |
|---|
|
TOP
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
REFERENCES
|
|---|
1. Bernard, G. R., A. Artigas, K. Brigham, J. Carlet, K. Falke, L. Hudson, M. Lamy, J. Legall, A. Morris, and R. Spragg. 1994. The American-European Consensus on ARDS: definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am. J. Respir. Crit. Care Med. 149: 818-824 [Abstract].
2. Doyle, R., N. Szaflarski, G. Modin, J. Wiener-Kronish, and M. Matthay. 1995. Identification of patients with acute lung injury. Predictors of mortality. Am. J. Respir. Crit. Care Med. 152: 1818-1824 [Abstract].
3.
Guinard, N.,
S. Beloucif,
C. Gatecel,
J. Mateo, and
D. Payen.
1997.
Evaluation of therapeutic optimization strategy in severe ARDS.
Chest
111:
1000-1007
4. Dehoux, M. S., A. Boutten, J. Ostinelli, N. Seta, M. C. Dombret, B. Crestani, M. Deschenes, J. L. Trouillet, and M. Aubier. 1994. Compartmentalized cytokine production within the human lung in unilateral pneumonia. Am. J. Respir. Crit. Care Med. 150: 710-716 [Abstract].
5. Chollet-Martin, S., C. Gatecel, N. Kermarrec, M. A. Gougerot-Pocidalo, and D. M. Payen. 1996. Alveolar neutrophil functions and cytokine levels in patients with the adult respiratory distress syndrome during nitric oxide inhalation. Am. J. Respir. Crit. Care Med. 153: 985-990 [Abstract].
6. Donnelly, S., R. Strieter, S. Kunkel, A. Walz, C. Robertson, D. Carter, I. Grant, A. Pollock, and C. Haslett. 1993. Interleukin-8 and development of adult respiratory distress syndrome in at-risk patients groups. Lancet 341: 643-647 [Medline].
7. Suter, P. M., S. Suter, E. Girardin, P. Roux-Lombard, G. E. Grau, and J. M. Dayer. 1992. High bronchoalveolar levels of tumor necrosis factor and its inhibitors, interleukin-1, interferon, and elastase, in patients with adult respiratory distress syndrome after trauma, shock, or sepsis. Am. Rev. Respir. Dis. 145: 1016-1022 [Medline].
8. Haymann, D., E. L'Her, J. M. NGuyen, S. Raher, I. Canfrère, L. Coupey, P. Fixe, E. Chailleux, D. De Groote, V. Praloran, and A. Godard. 1996. Leukaemia inhibitory factor production in pleural effusions: comparison with production of IL-4, IL-8, IL-10 and M-CSF. Cytokine 8: 410-416 [Medline].
9. Broaddus, V. C., C. A. Hèbert, R. V. Vitangcol, J. M. Hoeffel, M. S. Berstein, and A. M. Boylan. 1992. Interleukin-8 is a major neutrophil chemotactic factor in pleural liquid of patients with empyema. Am. Rev. Respir. Dis. 146: 825-830 [Medline].
10. Antony, V. B., S. W. Godey, S. L. Kunkel, J. W. Hott, D. L. Hartman, M. D. Burdick, and R. M. Strieter. 1993. Recruitment of inflammatory cells to pleural space: chemotactic cytokines, IL-8 and MCP-1 in human pleural fluids. J. Immunol. 151: 7216-7223 [Abstract].
11. Antony, V. B., J. W. Hott, S. L. Kunkel, S. W. Godbey, M. D. Burdick, and R. M. Strieter. 1995. Pleural mesothelial cell expression of C-C (monocyte chemotactic peptide) and C-X-C (interleukin 8) chemokines. Am. J. Respir. Cell Mol. Biol. 12: 581-588 [Abstract].
12. Barnes, P. F., S. J. Fong, P. J. Brennan, P. E. Twomey, A. Mazumder, and R. L. Modlin. 1990. Local production of tumor necrosis factor and IFN-gamma in tuberculous pleuritis. J. Immunol. 145: 149-154 [Abstract].
13.
Barnes, P. F.,
S. Lu,
J. S. Abrams,
E. Wang,
M. Yamamura, and
R. L. Modlin.
1993.
Cytokine production at the site of disease in human tuberculosis.
Infect. Immun.
61:
3482-3489
14. Maeda, J., N. Ueki, T. Ohkawa, N. Iwahashi, T. Nakano, T. Hada, and K. Higashino. 1993. Local production and localization of transforming growth factor-beta in tuberculous pleurisy. Clin. Exp. Immunol. 92: 32-38 [Medline].
15. Zhang, M., M. K. Gately, E. Wang, J. Gong, S. F. Wolf, S. Lu, R. L. Modlin, and P. F. Barnes. 1994. Interleukin 12 at the site of disease in tuberculosis. J. Clin. Invest. 93: 1733-1739 .
16.
Silva-Mejias, C.,
F. Gamboa-Antiñolo,
L. F. Lopez-Cortes,
M. Cruz-Ruiz, and
J. Pachon.
1995.
Interleukin-1 in pleural fluids of different
etiologies. Its role as inflammatory mediator in empyema.
Chest
108:
942-945
17.
Monti, G.,
M. C. Jaurand,
I. Monnet,
P. Chretien,
L. Saint-Etienne,
L. Zeng,
A. Portier,
P. Deviller,
P. Galanaud,
J. Bignon, and
D. Emilie.
1994.
Intrapleural production of interleukin-6 during mesothelioma
and its modulation by -interferon treatment.
Cancer Res.
54:
4419-4423
18. Fujino, S., and A.Yokoyama, N. Kohno, and K. Hiwada. 1996. Interleukin 6 is an autocrine growth factor for normal human pleural mesothelial cells. Am. J. Respir. Cell Mol. Biol. 14: 508-515 [Abstract].
19.
Lanfrancome, L.,
D. Boraschi,
P. Ghiara,
B. Falini,
F. Grignani,
G. Peri,
A. Mantovani, and
P. G. Pelicci.
1992.
Human peritoneal mesothelial cells produce many cytokines (G-CSF, GM-CSF, IL-1 and IL-6) and are activated and stimulated to grow by IL-1.
Blood
80:
2835-2842
20.
Chollet-Martin, S.,
P. Montravers,
C. Gibert,
C. Elbim,
J. M. Desmonts,
J. Y. Fagon, and
M. A. Gougerot-Pocidalo.
1993.
High levels of interleukin-8 in the blood and alveolar spaces of patients with pneumonia
and adult respiratory distress syndrome.
Infect. Immun.
61:
4553-4559
21.
Peters, M.,
S. Jacobs,
M. Ehler,
P. Vollmer,
J. Müllerg,
E. Wolf,
G. Brem,
K. H. Meyer, and
S. Rose-John.
1996.
The function of the soluble interleukin-6 receptor in vivo: sensitization of human soluble IL-6
receptor transgenic mice towards IL-6 and prolongation of the plasma
half-life of IL-6.
J. Exp. Med.
183:
1399-1406
22. Rouby, J. J., E. Martin De Lassale, P. Poete, M. H. Nicolas, L. Bodin, V. Jarlier, Y. Le Charpentier, J. Grosset, and P. Viars. 1992. Nosocomial bronchopneumonia in the critically ill: histologic and bacteriologic aspects. Am. Rev. Respir. Dis. 146: 1059-1066 [Medline].
23. Light, R., M. McGregor, P. Luchsinger, and W. Ball. 1972. Pleural effusions: the diagnostic separation of transudates and exudates. Ann. Intern. Med. 77: 507-513 .
24. Ledur, A., C. Fitting, B. David, C. Hamberger, and J. M. Cavaillon. 1995. Variable estimates of cytokine levels produced by commercial ELISA kits: results using international cytokine standards. J. Immunol. Methods 186: 171-179 [Medline].
25. Marty, C., B. Misset, F. Tamion, C. Fitting, J. Carlet, and J.-M. Cavaillon. 1994. Circulating interleukin-8 concentrations in patients with multiple organ failure of septic and nonseptic origin. Crit. Care Med. 22: 673-679 [Medline].
26. Muñoz, C., B. Misset, C. Fitting, J. P. Bleriot, J. Carlet, and J. M. Cavaillon. 1991. Dissociation between plasma and monocyte-associated cytokines during sepsis. Eur. J. Immunol. 21: 2177-2184 [Medline].
27.
Van Zee, K. J.,
T. Kohno,
E. Fischer,
C. S. Rock,
L. L. Moldawer, and
S. F. Lowry.
1992.
Tumor necrosis factor soluble receptors circulate
during experimental and clinical inflammation and can protect against
excessive tumor necrosis factor alpha in vitro and in vivo.
Proc. Natl.
Acad. Sci. U.S.A.
89:
4845-4849
28. van der Poll, T., J. Jansen, D. van Leenen, M. von der Mohlen, M. Levi, H. ten Cate, H. Gallati, J. W. ten Cate, and S. J. van Deventer. 1993. Release of soluble receptors for tumor necrosis factor in clinical sepsis and experimental endotoxemia. J. Infect. Dis. 168: 955-960 [Medline].
29.
Fischer, E.,
K. J. Van Zee,
M. A. Marano,
C. S. Rock,
J. S. Kenney,
D. D. Poutsiaka,
C. A. Dinarello,
S. F. Lowry, and
L. L. Moldawer.
1992.
Interleukin-1 receptor antagonist circulates in experimental inflammation and in human disease.
Blood
79:
2196-2200
30. Yanagawa, H., S. Yano, T. Haku, Y. Ohmoto, and S. Sone. 1996. Interleukin-1 receptor antagonist in pleural effusion due to inflammatory and malignant lung disease. Eur. Respir. J. 9: 1211-1216 [Abstract].
31.
Shimokata, K.,
H. Saka,
T. Murate,
Y. Hasegawa, and
T. Hasegawa.
1991.
Cytokine content in pleural effusion: comparison between tuberculosis and carcinomatous pleurisy.
Chest
99:
1103-1107
32. Yokoyama, A., N. Kohno, S. Fujino, M. Abe, O. Ishida, and K. Hiwada. 1996. Soluble interleukin-6 receptor levels in pleural effusions. Respir. Med. 90: 329-332 [Medline].
33.
Doré, P.,
E. Lelièvre,
F. Morel,
A. Brizard,
M. Fourcin,
C. Clément,
P. Ingrand,
L. Daneski,
H. Gascan,
J. Wijdenes,
J. Gombert,
J. L. Preudhomme, and
J. C. Lecron.
1997.
IL-6 soluble IL-6 receptors (sIL-6R
and sgp130) in human pleural effusions
massive IL-6 production independently of underlying diseases.
Clin. Exp. Immunol.
107:
182-188
[Medline].
34.
Negrini, D.,
D. Venturoli,
M. I. Townsley, and
R. K. Reed.
1994.
Permeability of parietal pleura to liquid and proteins.
J. Appl. Physiol.
76:
627-633
35. Cavaillon, J. M., C. Muñoz, C. Fitting, B. Misset, and J. Carlet. 1992. Circulating cytokines: the tip of the iceberg? Circ. Shock 38: 145-152 [Medline].
This article has been cited by other articles:
 |
|
 |
|
  J.-M. Cavaillon and D. Annane Invited review: Compartmentalization of the inflammatory response in sepsis and SIRS Innate Immunity, June 1, 2006; 12(3): 151 - 170. [Abstract] [PDF]
|
|
|
|
 |
|
 T. Weiss, I. Shalit, H. Blau, S. Werber, D. Halperin, A. Levitov, and I. Fabian Anti-Inflammatory Effects of Moxifloxacin on Activated Human Monocytic Cells: Inhibition of NF-{kappa}B and Mitogen-Activated Protein Kinase Activation and of Synthesis of Proinflammatory Cytokines Antimicrob. Agents Chemother., June 1, 2004; 48(6): 1974 - 1982. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. M. Porcel, M. Vives, and A. Esquerda Tumor Necrosis Factor-{alpha} in Pleural Fluid: A Marker of Complicated Parapneumonic Effusions Chest, January 1, 2004; 125(1): 160 - 164. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. A. Sasse, M. R. Jadus, and G. D. Kukes Pleural Fluid Transforming Growth Factor-{beta}1 Correlates with Pleural Fibrosis in Experimental Empyema Am. J. Respir. Crit. Care Med., September 15, 2003; 168(6): 700 - 705. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D H Strong, J Y Westcott, J A Biller, J L Morrison, R M Effros, and J P Maloney Eosinophilic "empyema" associated with crack cocaine use Thorax, September 1, 2003; 58(9): 823 - 824. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-M. Cavaillon, M. Adib-Conquy, I. Cloez-Tayarani, and C. Fitting Review: Immunodepression in sepsis and SIRS assessed by ex vivo cytokine production is not a generalized phenomenon: a review Innate Immunity, April 1, 2001; 7(2): 85 - 93. [Abstract] [PDF]
|
|
|
|
 |
|
 S. J. Ebong, S. M. Goyert, J. A. Nemzek, J. Kim, G. L. Bolgos, and D. G. Remick Critical Role of CD14 for Production of Proinflammatory Cytokines and Cytokine Inhibitors during Sepsis with Failure To Alter Morbidity or Mortality Infect. Immun., April 1, 2001; 69(4): 2099 - 2106. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. S. MUNFORD and J. PUGIN Normal Responses to Injury Prevent Systemic Inflammation and Can Be Immunosuppressive Am. J. Respir. Crit. Care Med., February 1, 2001; 163(2): 316 - 321. [Full Text]
|
|
|
|
|
|
D.-s. Cheng, Y. C. G. Lee, J. T. Rogers, E. A. Perkett, J. P. Moyers, R. M. Rodriguez, and R. W. Light Vascular Endothelial Growth Factor Level Correlates With Transforming Growth Factor-{beta} Isoform Levels in Pleural Effusions Chest, December 1, 2000; 118(6): 1747 - 1753. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Yamaguchi, H. Kimura, S. Yokota, Y. Yamamoto, T. Hashimoto, M. Nakagawa, M. Ito, and T. Ogura Effect of IL-6 Elevation in Malignant Pleural Effusion on Hyperfibrinogenemia in Lung Cancer Patients Jpn. J. Clin. Oncol., February 1, 2000; 30(2): 53 - 58. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Proc. Am. Thorac. Soc. | Am. J. Respir. Cell Mol. Biol. |