Lavage Neutrophil Counts Research Articles

Xanthine oxidase promotes neutrophil sequestration but not injury in hyperoxic lungs

Neutrophil accumulation in alveolar spaces is a conspicuous finding in hyperoxia-exposed lungs. We hypothesized that xanthine oxidase (XO)-derived oxidants contribute to retention of neutrophils in hyperoxic lungs. Rats were subjected to normobaric hyperoxia (100% O2) for 48 h, and lungs were assessed for neutrophil sequestration (morphometry and lavage cell counts) and injury (lavage albumin levels and lung weights). In rats exposed to hyperoxia, we found increased (P < 0.05) lung neutrophil retention, lavage albumin levels, and lung weights compared with normoxia-exposed control rats. Suppression of XO activity by pretreatment with allopurinol decreased (P < 0.05) lung neutrophil retention but increased (P < 0.05) lavage albumin concentrations and lung weights in hyperoxic rats. Allopurinol treatment had no effect (P > 0.05) on the numbers of macrophages or lymphocytes recoverable by lung lavage. Depletion of XO activity by an independent method, tungsten feeding, also decreased (P < 0.05) lung lavage neutrophil counts and increased (P < 0.05) lavage albumin concentrations. We conclude that XO may be involved in lung neutrophil retention but not lung injury during exposure to hyperoxia.

Lavage versus serum measurements of lysozyme, angiotensin converting enzyme and other inflammatory markers in pulmonary sarcoidosis

The aim of this study was to explore whether amounts of angiotensin converting enzyme (ACE) and lysozyme produced within the lungs correlate more closely than serum levels of these enzymes, or other inflammatory markers, with chest radiographic profusion scores, lung function and therapy response in patients with pulmonary sarcoidosis. We have studied 25 patients, and levels in bronchoalveolar lavage (BAL) were used to determine "local" enzyme production by reference to serum and lavage albumin. Before treatment, serum lysozyme levels were elevated in more patients (80%) than serum ACE levels (40%). They also gave the best overall correlation with clinical measurements prior to treatment and falls in serum lysozyme closely parallelled improvement in lung function (transfer factor for carbon monoxide (DLCO)) on therapy. The only other markers showing significant correlations with disease severity were lavage neutrophil counts per ml and "local" ACE measurements prior to treatment. The value of pre-treatment levels of the different inflammatory markers in predicting response to corticosteroid therapy was explored and the only significant finding was that BAL lymphocyte percentages and numbers.ml-1 were initially higher in patients with lower post-treatment chest X-ray scores (p less than 0.01 and p less than 0.05, respectively). We conclude that serum lysozyme levels appear to be a more useful marker of overall disease activity in sarcoidosis than measurements of other inflammatory markers. However, BAL lymphocyte counts were the best predictive marker of radiographic response to corticosteroids.

Bronchoalveolar Lavage Fluid Angiotensin-converting Enzyme in Interstitial Lung Diseases

In this study we evaluated the disease specificity of bronchoalveolar lavage fluid angiotensin-converting enzyme (BALF-ACE), its correlation with cellular constituents of bronchoalveolar lavage fluid (BALF), and for sarcoidosis, with other proposed markers of disease activity. Furthermore, the question of the clinical value of BALF-ACE determinations in in interstitial lung diseases or any of its subgroups was addressed. The study population consisted of 222 patients, 69 with biopsy proven sarcoidosis, 3 with hypersensitivity pneumonitis, 4 with acute histoplasmosis, 27 with idiopathic pulmonary fibrosis (IPF), 4 with rheumatoid arthritis-related interstitial fibrosis, 9 with pulmonary drug toxicity, 16 with pulmonary malignancies, 26 with other parenchymal lung disease entities, and 30 in whom the final diagnosis remained indeterminate. Elevated BALF-ACE concentrations were seen in all diagnostic categories. In sarcoidosis BALF-ACE levels correlated well with lavage lymphocyte counts (r = 0.49; p less than 0.0001), in contrast to IPF where they correlated well with lavage neutrophil counts (r = 0.51; p less than 0.007). The correlation of BALF-ACE and serum-ACE was significant. In sarcoidosis the mean BALF-ACE level was lower for patients with Stage-I chest roentgenographic patterns (0.664 U/L), compared to those with Stage II (1.112 U/L) and Stage III (1.083 U/L). It was concluded that elevated BALF-ACE levels are not specific for sarcoidosis. The correlations of BALF-ACE levels with different cellular constituents of BALF suggest a different cellular origin of BALF-ACE. In sarcoidosis BALF-ACE levels correlate well with other proposed markers of disease activity and seem to reflect pulmonary activity better than serum ACE.(ABSTRACT TRUNCATED AT 250 WORDS)

Gold treatment for kala-azar.

We hypothesized that endotoxin injection in rats would stimulate in vivo nuclear factor-kappa B (NF-kappa B) activation in lung tissue and that antioxidant treatment before endotoxin injection would attenuate endotoxin-induced NF-kappa B activation, chemokine gene expression, and neutrophilic lung inflammation. We studied NF-kappa B activation in rat lung tissue following a single i.p. injection of endotoxin (6 mg/kg). After in vivo endotoxin treatment, lung NF-kappa B activation peaked at 2 h and temporally correlated with the expression of cytokine-induced neutrophil chemoattractant mRNA in lung tissue. Treatment with the antioxidant N-acetylcysteine (NAC) 1 h before endotoxin resulted in decreased lung NF-kappa B activation in a dose-dependent manner (from 200-1000 mg/kg) and diminished cytokine-induced neutrophil chemoattractant mRNA expression in lung tissue. Treatment with NAC significantly suppressed endotoxin-induced neutrophilic alveolitis. The average total lung lavage neutrophil count was 5.5 x 10(6) with endotoxin treatment vs 0.9 x 10(6) with NAC treatment before endotoxin. The NF-kappa B pathway represents an attractive therapeutic target for strategies to control neutrophilic inflammation and lung injury.

Corticosteroid treatment in pulmonary sarcoidosis: do serial lavage lymphocyte counts, serum angiotensin converting enzyme measurements, and gallium-67 scans help management?

Thirty two patients with persisting pulmonary sarcoidosis fulfilling defined criteria for treatment were managed according to a standard clinical protocol. In this an attempt was made to achieve and maintain maximal radiographic and physiological improvement with individually titrated doses of corticosteroids. Lavage cell counts, serum angiotensin converting enzyme (SACE) determinations, and gallium-67 scans were planned at standard intervals but were not used in management decisions. The study analysed serial measurements in relation to changes in the clinical measurements. Twelve patients' radiographs showed complete clearing, seven cleared partially, and 13 had partial clearing with evidence of fibrosis. There was no predictive value in the initial lavage lymphocyte counts or the SACE or gallium measurements. Notably, in seven patients, substantial radiographic improvement was observed when the initial lavage lymphocyte counts were normal. Higher initial lavage neutrophil counts (p less than 0.02), higher initial radiographic profusion scores (p less than 0.02), and lower vital capacity (p less than 0.01) and carbon monoxide transfer factor (p less than 0.05) were related to incomplete clearing. A repeat study of the patients when their radiograph had cleared maximally showed that the levels of lavage lymphocytes, SACE, and gallium tended to fall, but frequently remained raised even in the presence of a normal radiograph or vital capacity or both. On the other hand, however, most of the patients with a normal lavage lymphocyte count showed persisting abnormality of the radiograph, lung function measurements, SACE, and gallium scan (or of at least one of these indices). The interrelationships between changes in clinical indices (radiograph, vital capacity, and transfer factor) and in lavage lymphocyte counts, SACE, and gallium scans showed that concordance was fairly poor in each comparison; lavage lymphocytes showed a greater major discordance than did the other pairs of measurements. Symptom free patients with normal or stable radiographic appearances have been followed for many months and have shown no clinical deterioration despite abnormal lavage lymphocyte counts, SACE, and gallium scans. Radiographic relapse, within the criteria defined, was seen in only four patients during the study; this was reflected in the gallium counts in three and in SACE and lavage lymphocyte counts measurements in two. It is concluded that serial lavage lymphocyte counts, serum angiotensin converting enzyme measurements, and gallium-67 scans are not consistently more sensitive methods by which to monitor patients with sarcoidosis during treatment than are serial measurements of high quality radiographs and results of standard lung function tests.

The effects of hyperoxia on pulmonary clearance of Pseudomonas aeruginosa.

Among the toxic effects of hyperoxia may be impaired pulmonary clearance of gram-negative bacteria. To better define this effect, we exposed BALB/c mice to 100% O2 for 24, 48, or 72 hr and intrabronchially inoculated them with 10(6) Pseudomonas aeruginosa. Clearance was assessed 4 hr later by quantitative lung cultures of air- and O2-exposed mice. Clearance was first reduced at 48 and 72 hr in mice exposed to O2. To determine the mechanism responsible, we measured bronchoalveolar lavage neutrophil (PMN) counts and neutrophil chemotactic activity at 0, 2, and 4 hr after instillation of P. aeruginosa into mice first exposed to air or O2 for 48 hr. Air-exposed mice had more PMNs than did O2-exposed mice after challenge (13.3 +/- 2.1 X 10(5) vs. 4.4 +/- 0.6 X 10(5)). There was no difference in neutrophil chemotactic activity between air- and O2-exposed mice at any time, although chemotactic activity increased in both groups after challenge. Our data suggest that hyperoxia impairs pulmonary clearance of P. aeruginosa by decreasing the influx of PMNs and that this effect is not due to diminished chemotactic activity in bronchoalveolar lavage fluid.

Ahaptoglobinaemia and predisposition to iron-deficiency anaemia.

Clearance of neutrophils from inflamed sites is critical for resolution of inflammation, but pathogen-driven neutrophil apoptosis can impair host defenses. We previously showed that pyocyanin, a phenazine toxic metabolite produced by <i>Pseudomonas aeruginosa</i>, accelerates neutrophil apoptosis in vitro. We compared wild-type and pyocyanin-deficient strains of <i>P. aeruginosa</i> in a murine model of acute pneumonia. Intratracheal instillation of either strain of <i>P. aeruginosa</i> caused a rapid increase in bronchoalveolar lavage neutrophil counts up to 18 h after infection. In wild-type infection, neutrophil numbers then declined steadily, whereas neutrophil numbers increased up to 48 h in mice infected with pyocyanin-deficient <i>P. aeruginosa</i>. In keeping with these differences, pyocyanin production was associated with reduced bacterial clearance from the lungs. Neutrophil apoptosis was increased in mice infected with wild-type compared with the phenazine-deficient strain or two further strains that lack pyocyanin production, but produce other phenazines. Concentrations of potent neutrophil chemokines (MIP-2, KC) and cytokines (IL-6, IL-1β) were significantly lower in wild-type compared with phenazine-deficient strain-infected mice at 18 h. We conclude that pyocyanin production by <i>P. aeruginosa</i> suppresses the acute inflammatory response by pathogen-driven acceleration of neutrophil apoptosis and by reducing local inflammation, and that this is advantageous for bacterial survival.