Elevated levels of NAP-1/interleukin-8 are present in the airspaces of patients with the adult respiratory distress syndrome and are associated with increased mortality.

The adult respiratory distress syndrome (ARDS) is characterized by increased neutrophils within the airspaces of the lungs. In order to determine if neutrophil activating protein (NAP)-1/interleukin-8 (NAP-1/IL-8) could be an important cause of neutrophil influx and activation in ARDS, we examined fluid, which was either directly aspirated or lavaged with saline from the lungs of patients with ARDS. NAP-1/IL-8 was present in significantly higher concentrations in the fluids of patients with ARDS compared with control subjects. There was a significant correlation between the percentage of neutrophils in the lavage fluids and the NAP-1/IL-8 concentration (r2 = 0.74). Furthermore, the NAP-1/IL-8 concentration of the pulmonary edema fluid was equivalent to the optimal concentration required to induce neutrophil chemotaxis in vitro. Although not all of the chemotactic activity of the edema fluid was removed by an anti-NAP-1/IL-8 affinity column, the data established that NAP-1/IL-8 is an important neutrophil chemotaxin in the airspaces of patients with ARDS. In addition, those patients with very high concentrations of NAP-1/IL-8 in their bronchoalveolar lavage fluids had a higher mortality rate than those patients with lower concentrations of NAP-1/IL-8. The correlation between NAP-1/IL-8 concentration and mortality is not paralleled by total protein concentration and mortality.     

Serial observation of lymphocyte subpopulations and interleukin 2 production of T cells from patients with acute viral hepatitis and chronic active hepatitis

T cell subpopulations and interleukin 2 (IL-2) production of T cells in peripheral blood from patients with acute viral hepatitis (AVH) and chronic active hepatitis (CAH) were studied to elucidate the change of T cells functions during the exacerbation of viral hepatitis. The ratio of the number of CD4-positive cells to CD8-positive cells (CD:CD8 ratio) was increased in many patients with AVH. During exacerbation of CAH, the CD4:CD8 ratio was higher than that during remission (p less than 0.01), due to a decrease in the number of CD8-positive cells. IL2 production of T cells in AVH and CAH with bridging necrosis was higher than that of T cells in normal controls (p less than 0.01, p less than 0.05, respectively). T cells from patients with CAH produced more IL2 during exacerbation than during remission (p less than 0.01). IL2 production of T cells and the CD4:CD8 ratio (p less than 0.005, p less than 0.01). The change in T cell subpopulations in AVH and during exacerbation of CAH was found to induce an immunological condition, in which T cells easily produce IL2, which induces a proliferation of cytotoxic T cells.     

Asthmatic patients have neutrophils that exhibit diminished responsiveness to adenosine

Activation of neutrophils (PMN) within the airways results in the secretion of a number of products such as reduced oxygen metabolites that could contribute to the inflammatory response associated with asthma. However, mediators of allergy, such as histamine, prostaglandin E2 (PGE2), isoproterenol, and adenosine, may serve to mitigate this inflammation through feedback inhibition of neutrophil function. To test the hypothesis that PMN activation and feedback inhibition mechanisms may be abnormal in asthmatics, we compared both superoxide production and adenosine-induced suppression of superoxide production in 12 matched pairs of asthmatics and control subjects. PMN obtained from asthmatic patients generated significantly more superoxide in response to f-met-leu-phe (fMLP) than controls (2.94 +/- 55 nmol/5 x 10(5) PMN/5 min versus 1.38 +/- 0.35 at 2 x 10(-8) M fMLP and 3.81 +/- 0.68 nmol versus 2.04 +/- 0.45 nmol at 10(-7) M; p less than 0.01 for both). In contrast, the respiratory burst generated by two receptor-independent stimuli, the calcium ionophore A23187 and phorbol myristate acetate, was equivalent between control and asthmatic subjects. At 10(-6) M, 2-chloroadenosine induced a 19.5 +/- 5.1% inhibition of fMLP-stimulated superoxide production in PMN from patients with asthma as compared to 55.6 +/- 24.6% inhibition in PMN from control subjects (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Toxic oxygen metabolite production by circulating phagocytic cells in inflammatory bowel disease.

To investigate the possibility that the oxidative capacity of phagocytic cells may be defective in inflammatory bowel disease, toxic oxygen metabolite production by circulating neutrophils and monocytes has been measured by luminol dependent chemiluminescence. Neutrophils from patients with Crohn's disease and ulcerative colitis produced significantly lower chemiluminescent responses after chemotactic stimulation with formylmethionylleucylphenylalanine (fMLP) than neutrophils from control patients, p = 0.018 and 0.043 respectively. Chemiluminescent responses of neutrophils from patients with inflammatory bowel disease, however, were similar to control responses when cells were stimulated with latex beads or phorbol myristate acetate. Monocytes from patients with Crohn's disease produced significantly greater levels of chemiluminescence than control monocytes when stimulated with either fMLP (p less than 0.002), phorbol myristate acetate (p less than 0.0005) or latex beads (p less than 0.002). Monocytes from patients with ulcerative colitis also produced significantly greater levels of chemiluminescence than controls when stimulated with latex beads (p less than 0.5) or phorbol myristate acetate (p less than 0.0005), although there was no difference in the level of chemiluminescence in response to fMLP. These results exclude a generalised defect in phagocytic cell oxidase activity in inflammatory bowel disease and suggest that circulating monocytes are 'activated'.     

Plasma neutrophil-activating peptide-1/interleukin-8 and neutrophil elastase in a primate bacteremia model

A hyperdynamic sepsis model was set up in seven adult baboons to evaluate neutrophil-activating peptide-1/interleukin (IL)-8 (NAP-1/IL-8), IL-1 beta, IL-6, tumor necrosis factor-alpha (TNF alpha), and IFN-gamma in plasma. By continuous intravenous administration of 10(10) cfu/kg live Escherichia coli over 8 h with additional infusion therapy (less than or equal to 50 ml/kg/h), endotoxin plasma levels of 2.7-22.3 ng/ml were observed. In plasma the kinetics of NAP-1/IL-8 and IL-6 were similar to those of IL-1 at the end of the experiment (8 h) (peak median values, 34, 4197, and 230 ng/ml, respectively). Differences were greatest for IL-6. Monocyte activation during sepsis was confirmed by elevated plasma neopterin levels (91-139 mumol/mmol of creatine). Granulocyte activation was evident from both incipient neutropenia and the massive release of neutrophil elastase into the plasma as measured by a new immunoassay (peak level, 374 ng/ml). Thus, in primate bacteremia, early TNF release is followed by a concomitant increase of NAP-1/IL-8 with plasma kinetics similar to those of IL-6 and IL-1 and accompanied by massive activation of neutrophils.     

Soluble interleukin 2 receptors in autoimmune chronic active hepatitis.

Children with uncontrolled autoimmune chronic active hepatitis have increased numbers of activated T lymphocytes expressing interleukin 2 receptors (IL2R). A soluble form of IL2R has recently been described whose proposed role is to downregulate T cell activation by competing for interleukin 2. We investigated whether a deficiency of soluble IL2R could account for the high concentrations of IL2R positive T lymphocytes in autoimmune chronic active hepatitis. Soluble IL2R was measured by enzyme-linked immunosorbent assay in the serum of 16 children with autoimmune chronic active hepatitis, eight with chronic liver disease due to hepatitis B virus infection, seven with Wilson's disease, nine with alpha 1 antitrypsin deficiency, and 15 healthy age matched controls. Soluble IL2R concentration was significantly higher in patients with autoimmune chronic active hepatitis than in healthy controls (mean (SEM) 475 (75) U/ml, 145 (8) U/ml respectively, p less than 0.01). Eleven patients who had active disease had significantly higher soluble IL2R concentrations (590 (89) U/ml) than the five cases with inactive disease (220 (36) U/ml, p less than 0.01). No difference was found between the controls and the patients with chronic liver disease due to hepatitis B infection, Wilson's disease, and alpha 1 antitrypsin deficiency. Percentages and absolute numbers of surface IL2R positive T cells as detected by immunofluorescence were significantly higher in the patients with autoimmune chronic active hepatitis (11.8% (1); 274/microliters (31)) than in controls (0.2% (0.1); 5/microliters (2), p less than 0.001), the highest values being found in those with uncontrolled disease. A significantly positive correlation was observed between concentrations of soluble IL2R and the percentage of T cells expressing IL2 receptors (r=0.67, p<0.001). These results indicate that the high levels of IL2R positive T lymphocytes characteristic of autoimmune chronic active hepatitis are not due to a deficiency of soluble IL2 receptors.     

秋水仙碱对大鼠肺纤维化的干预作用

目的研究秋水仙碱（Ｃｏｌｃ．）对博菜霉素（ＢＬＭ）所致大鼠肺纤维化的干预作用，探讨治疗肺间质纤维化的新途径。方法Ｗｉｓｔａｒ大鼠随机分为３组，每组２５只，１组为ＢＬＭ组，气管内注入０．５％ＢＬＭＡ５０．１ｍｌ／１００ｇ体重，复制肺纤维化动物模型，２组为生理盐水对照组，３组为药物干预组，大鼠于ＢＬＭ灌注后每日胃内灌入Ｃｏｌｃ．１０μｇ／１００ｇ体重。三组动物于气管内灌注后第１、３、７、１４、２８天分别随机处死５只，进行支气管肺泡灌洗并收集灌洗液。采用生物活性检测法，测定肺泡巨噬细胞释放细胞因子的变化，细胞外基质蛋白及脂质过氧化损伤的检测，分别采用放免法及生化法。结果秋水仙碱组于灌胃后第７～２８天，白细胞介素６（ＩＬ－６）水平较ＢＬＭ组降低（Ｐ＜０．０５），但仍高于对照组；ＩＬ－８于第１～３天显著下降（Ｐ＜０．０１）；肺内羟脯氨酸（ＨＹＰ）及纤维连结蛋白（ＦＮ）、层粘连蛋白（ＬＮ）含量明显降低。Ｃｏｌｃ．对脂质过氧化损伤未显示出防护作用。结论秋水仙碱对大鼠实验性肺纤维化有一定防护作用     

Allergen-induced mucosal exudation of plasma into rat ileum and its inhibition by budesonide.

Exudation of plasma across the airway mucosa is a specific defence/inflammatory response finely regulated by mediators and (in rodents) a capsaicin-sensitive innervation. This study examines plasma exudation responses to endointestinal challenges and effects of a glucocorticoid. The ileum of anesthetized rats was catheterized and ligated at two points 10 cm apart for mucosal challenge (0.5 ml) and repeated lavages (5 ml). Lavage fluid levels of the plasma tracer 125I-albumin, previously injected intravenously, showed a stable, low base line greater than 2 h. Challenge with mediators (10(-5) M bradykinin, 10(-5)-10(-3) M serotonin, 10(-6)-10(-4) M histamine, 2.10(-9)-2.10(-7) M leukotriene D4 (LTD4), or 10(-5)-10(-3) M capsaicin did not increase luminal radioactivity. However, allergen (10(-6) M ovalbumin, in previously sensitized animals) produced prompt mucosal exudation of 125I-albumin, peaking within 30 min (p less than 0.001) and returning to base line within 90 min. Separate experiments suggested that absorption was not increased during the mucosal exudation. The glucocorticoid budesonide (10-1000 micrograms/kg given by gavage 24 h before challenge) dose-dependently inhibited the allergen-induced exudation (p less than 0.01). The route of administration and the antiexudative versus the systemic potency (reduced thymus weight) suggest the possibility of a topical action of budesonide. We conclude that endointestinal allergen challenge produces reversible and glucocorticoid-inhibitable exudation of plasma across the mucosa. It appears less likely that bradykinin, serotonin, histamine, LTD4, or a capsaicin-sensitive innervation is involved in producing this exudative effect.     

Secretion of neutrophil attractant/activation protein by lipopolysaccharide-stimulated lung macrophages determined by both enzyme-linked immunosorbent assay and N-terminal sequence analysis

Alveolar macrophages contribute to acute pulmonary inflammation by secretion of neutrophil chemoattractants. We determined if one of these attractants is neutrophil attractant/activating protein (NAP-1), which is secreted by blood monocytes stimulated by lipopolysaccharide (LPS). Alveolar macrophages were stimulated in tissue culture with 10 micrograms/ml LPS. Culture fluids collected at 24 h were assayed for both neutrophil chemotactic activity and the concentration of NAP-1 as determined by a sandwich ELISA. The concentration of NAP-1 in culture fluid to LPS-stimulated macrophages was 860 +/- 40 ng/ml (SEM for six normal subjects). NAP-1 in fluid of unstimulated macrophages was 40 +/- 15 ng/ml. We confirmed the presence of NAP-1 in culture fluid of LPS-stimulated lung macrophages by immunoaffinity and HPLC-CM column purification. The HPLC-CM elution profile of macrophage NAP-1 was identical to that of monocyte NAP-1, and the N-terminal sequence of the protein in one of the isolated peaks corresponded to that of monocyte-derived NAP-1 beta. Two lines of evidence show that NAP-1 does not account for all neutrophil chemotactic activity in culture fluid of 24-h, LPS-stimulated macrophages. At a dilution of culture fluid that elcited the same chemotactic response as a known concentration of pure NAP-1, the concentration of culture fluid NAP-1 was only one-tenth that of pure NAP-1. (ABSTRACT TRUNCATED AT 250 WORDS)     

Interleukin 1 and poly(rI).poly(rC) induce production of granulocyte CSF, macrophage CSF, and granulocyte-macrophage CSF by human endothelial cells

Electrophoretically pure human interleukin 1 (IL-1) beta was found to stimulate human endothelial cells in monolayer culture to elaborate colony-stimulating activity (CSA). Supernatant fluids from cultures stimulated with increasing concentrations of IL-1 were found to stimulate colony formation of myeloid (CFU-GM), erythroid (BFU-E), and multipotent (CFU-GEMM) progenitor cells in a dose-dependent fashion. The effect on mixed colony formation, however, was less than on CFU-GM and BFU-E growth. Similar to IL-1, the double-stranded RNA polyriboinosinic-polyribocytidilic acid (poly[rI].poly[rC]) also stimulated release of CSA by endothelial cells in a dose-dependent manner. The kinetics of IL-1-induced CSA release as opposed to poly(rI).poly(rC)-induced release were found to be different, in that poly(rI).poly(rC)-induced CSA production occurred more slowly. An anti-IL-1 beta antiserum was able to completely neutralize the IL-1-induced CSA release, but had no effect on poly(rI).poly(rC)-dependent CSA production, indicating that the latter effect was mediated by other mechanisms than intermediate production of IL-1 beta. Using specific immunologic assays, IL-1- as well as poly(rI).poly(rC)-inducible production of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF, and macrophage CSF was found. The release of CSF from endothelial cells in response to IL-1 may be a mechanism for stimulating production of neutrophils and mononuclear phagocytes, and for attracting and activating these cells at sites of inflammation.     

Effect of cyclic AMP on ciliary activity of human respiratory epithelium.

In order to investigate the effect of cyclic adenosine monophosphate (cAMP) on ciliary beat frequency (CBF) in human respiratory epithelium, cells were brushed from the inferior nasal turbinates of three groups of ten subjects: awake adults (aged 20-34 yrs), anaesthetized children (2-15 yrs) and anaesthetized adults (19-61 yrs). Cells from the awake adults were also studied after storage for 24 h in tissue culture medium. CBF was measured in vitro with a photometric technique at room temperature (22.0 +/- 1.5 degrees C). Samples were mounted in a perfusion chamber and challenged with either control solutions, dibutyryl cAMP (10(-4) or 10(-3) M), or the cyclic nucleotide-dependent protein kinase inhibitor 1-(5-isoquinolinylsulphonyl)-2-methylpiperazine (H-7). Dibutyryl cAMP (10(-3) M) caused a significant increase in CBF in all groups studied: awake adults (+1.1 Hz; p less than 0.01), anaesthetized children (+1.2 Hz; p less than 0.01), anaesthetized adults (+1.2 Hz; p less than 0.01), stored cells (+1.1 Hz; p less than 0.01). This response was inhibited by preincubation with H-7 (10(-4) and 10(-3) M). It is concluded that cAMP is a regulator of ciliary activity in human respiratory epithelium.     

Different functions for the interleukin 8 receptors (IL-8R) of human neutrophil leukocytes: NADPH oxidase and phospholipase D are activated through IL-8R1 but not IL-8R2.

Two monoclonal antibodies, anti-IL8R1 and anti-IL8R2, raised against both interleukin 8 receptors (IL-8R) of human neutrophils, IL-8R1 and IL-8R2, were used to study individual receptor functions after stimulation with IL-8, GRO alpha, or NAP-2. Efficacy and selectivity of the antibodies were tested in Jurkat cells transfected with cDNA coding for one or the other receptor. The binding of 125 I labeled IL-8 and IL-8-induced changes of the cytosolic free Ca2+ concentration were inhibited by anti-IL8RI in cells expressing IL-8R1 and by anti-IL8R2 in cells expressing IL-8R2. In human neutrophils, release of elastase was observed after stimulation with IL-8 or GRO alpha. The response to IL-8 was inhibited slightly by anti-IL8R1 and more substantially when both monoclonal antibodies were present, while the response to GRO alpha was inhibited by anti-IL8R2 but was not affected by anti-IL8R1. These results indicate that both IL-8 receptors can signal independently for granule enzyme release. Superoxide production, a measure of the respiratory burst, was obtained with increasing concentrations of IL-8 with maximum effects at 25 to 50 nM, but no response was observed upon challenge with GRO alpha or NAP-2 up to 1000 nM. The superoxide production induced by IL-8 was inhibited by anti-IL8R1, but was not affected by anti-IL8R2. Stimulation of neutrophils with IL-8, in contrast to GRO alpha or NAP-2, also elicited phospholipase D activity. The effect of IL-8 was again inhibited by anti-IL-8R1 but not by anti-IL8R2, indicating that this response, like the respiratory burst, was mediated by IL-8R1. Taken together, our results show that IL-8R1 and IL-8R2 are functionally different. Responses, such as cytosolic free Ca2+ changes and the release of granule enzymes, are mediated through both receptors, whereas the respiratory burst and the activation of phospholipase D depend exclusively on stimulation through IL-8R1.     

Functional loss of chemotactic factor inactivator in the adult respiratory distress syndrome

The adult respiratory distress syndrome (ARDS) is often characterized by a neutrophilic alveolitis, which may be mediated in part by the neutrophil chemoattractant, C5a. Chemotactic factor inactivator (CFI) can decrease C5a-directed neutrophil chemotaxis. Thus, a loss of CFI activity in the ARDS lung could lead to an increased ability of C5a to attract neutrophils. Lung CFI levels were measured antigenically and functionally in bronchoalveolar lavage (BAL) fluid obtained from 29 patients with ARDS and in 14 normal control subjects. Antigenic levels of CFI were found to be markedly elevated in ARDS BAL fluid (1,855 +/- 437 ng/ml) compared with that in normal BAL (29 +/- 10 ng/ml, p less than 0.005), but, in contrast, CFI functional activity was markedly decreased in ARDS BAL fluid compared with that in normal BAL fluid (31 +/- 7% inhibition versus 76 +/- 5% inhibition, p less than 0.01). Furthermore, although purified CFI readily inhibited the ability of C5a to attract neutrophils (92% inhibition), this activity was decreased when BAL fluid from patients with ARDS was incubated with CFI (47 +/- 10%, p less than 0.01). These findings suggest that patients with ARDS are functionally deficient in CFI, leading to an increased ability of C5a to attract neutrophils.     

High- and low-affinity binding of GRO alpha and neutrophil-activating peptide 2 to interleukin 8 receptors on human neutrophils.

GRO alpha and neutrophil-activating peptide 2 (NAP-2), like their analog interleukin 8 (IL-8), are considered to be inflammatory mediators since they recruit and activate neutrophil leukocytes. After introduction of tyrosines by substitution for other residues at the C terminus, GRO alpha and NAP-2 were labeled with 125I and used for binding studies. A total of 60,000-90,000 receptors per neutrophil were found for either ligand. Of these 30-45% were of high affinity with a mean Kd value of 0.3 and 0.7 nM for GRO alpha and NAP-2, respectively, and 55-70% of low affinity (Kd = 30 nM). Two proteins of approximately 70 kDa and 44 kDa (p70 and p44) were specifically cross-linked with labeled GRO alpha, NAP-2, and IL-8. Unlabeled IL-8 fully inhibited this cross-linking and the binding of labeled GRO alpha or NAP-2 to the high-affinity sites on neutrophils or neutrophil membranes. Treatment of membranes with digitonin resulted in the preferential solubilization of a single receptor species, corresponding to p44, that bound GRO alpha and NAP-2 with low affinity (Kd = 30 nM) and IL-8 with high affinity (Kd = 0.4 nM). Exposure of neutrophil membranes to 100 microM guanosine 5'-[gamma-thio]triphosphate led to a 75-fold increase of the Kd in approximately 60% of the IL-8 receptors. High-affinity receptors for GRO alpha and NAP-2 were similarly affected. In contrast, guanosine 5'-[gamma-thio]triphosphate had no effect on the binding of IL-8 to p44 solubilized by digitonin. These results demonstrate that human neutrophils bear two classes of receptors for GRO alpha, NAP-2, and IL-8 (p70 and p44) that may differ in their mode of interaction with GTP regulatory proteins.     

RANTES- and interleukin-8-induced responses in normal human eosinophils: effects of priming with interleukin-5

We report that responses of normal human eosinophils toward the chemokines RANTES and interleukin-8 (IL-8) are modulated and upregulated by priming with IL-5. In a modified Boyden chamber assay, we studied migratory responses toward the members of the chemokine family RANTES, monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1 alpha (MIP-1 alpha) (C-C subfamily), and IL-8, platelet factor-4 (PF-4), and neutrophil-activating peptide-2 (NAP-2) (C-x-C subfamily). These chemokines were also studied in terms of actin polymerization and ([Ca2+]i)-mobilizing properties, intracellular signals that are thought to play a role during migratory responses. We found that eosinophils showed significant migratory responses toward RANTES and IL-8 at concentrations of 10(-9) to 10(-7) mol/L only after priming with IL-5 (10 pmol/L). At these concentrations, PF-4, NAP-2, MCP-1, and MIP-1 alpha induced no significant migratory responses after priming. Unprimed eosinophils only showed a significant migratory response toward RANTES (10(-6) mol/L). Changes in [Ca2+]i were found after addition of RANTES, MIP-1 alpha, and NAP-2 (10 nmol/L) to unprimed eosinophils. RANTES (10(-9) to 10(-7) mol/L) significantly induced actin polymerization both in primed and unprimed eosinophils, whereas IL-8 (10(-9) to 10(-8) mol/L) and MIP-1 alpha (10(-8) mol/L) only induced actin polymerization after priming with IL-5. NAP-2, PF-4, and MCP-1 did not affect actin polymerization. These findings are further evidence for the hypothesis that cytokines like IL-5 and locally secreted chemokines like RANTES and IL-8 are both at the basis of specific eosinophil influx into the allergic inflammatory locus.     

Differences in oxidative response of subpopulations of neutrophils from healthy subjects and patients with rheumatoid arthritis.

OBJECTIVES--To determine whether blood neutrophils from healthy individuals and blood and synovial fluid neutrophils from patients with rheumatoid arthritis (RA) responded differently to priming agonists and stimuli of the oxidative burst and, if so, whether this was a property of a subpopulation of neutrophils. METHODS--Continuous flow electrophoresis was used to separate neutrophils into subpopulations based upon quantitative differences in net negative surface charge. The generation of superoxide anion (O2-) was used as a measure of oxidative activity using 10(-7) mol/l N-formyl-methionylleucyl-phenylalanine (FMLP) as the stimulating agonist and 10(-8) mol/l platelet activating factor (PAF) as the priming agent. RESULTS--The production of O2- by blood and synovial fluid neutrophils from RA patients in response to FMLP was greater than that observed with control blood neutrophils (p < 0.001). Priming of normal blood neutrophils with PAF increased their FMLP induced oxidative burst (p < 0.001), but PAF treatment had no effect on rheumatoid neutrophils. Neutrophils from synovial fluid of RA patients were less electronegative than paired blood samples and exposure of blood neutrophils to FMLP but not PAF reduced their surface charge. Continuous flow electrophoresis isolated three neutrophil subpopulations: cells of least surface electronegativity were ascribed to pool P1 and cells of greatest surface electro-negativity to P3. Normal blood neutrophils from P3, but not P1, showed increased oxidative activity after PAF priming (twofold increase; p < 0.01), whereas the responsiveness of rheumatoid blood and synovial fluid neutrophils from P1 and P3 was not modified by PAF treatment under the same conditions. CONCLUSION--It is suggested that most of the circulating neutrophils in RA are already in a state of readiness to generate O2- upon activation by an inflammatory stimulus. This is in contrast to normal blood neutrophils, which have both responsive and non-responsive subpopulations with respect to priming agonists.     

Granulocytes from chronic myeloid leukemia (CML) patients show differential response to different chemoattractants

Binding of chemoattractant to polymorphonuclear leukocytes (PMNL) triggers a series of events like polymerization of actin and tubulin, orientation of cells, chemotaxis, increase in fluid pinocytosis and phagocytosis, and stimulation of microbicidal pathways which includes lysosomal degranulation and generation of reactive oxygen species. Earlier studies from our laboratory have shown that stimulation of chemotaxis, fluid pinocytosis, and actin polymerization of CML PMNL in response to a synthetic chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP) is significantly lower than that in normal PMNL. It is not known whether this lower response of CML PMNL to fMLP is a global phenomenon involving different chemoattractant receptors or is restricted to the fMLP pathway. We have evaluated chemoattractant induced degranulation process in normal and CML PMNL to fMLP, platelet activating factor (PAF), leukotriene B₄ (LTB₄), and an analogue of fMLP viz formyl-methionine-1 aminocyclooctane 1 carboxylic acid-phenylalanine-O-methionine (FACC⁸) using release of lysozyme as a parameter. We find that after stimulation with fMLP and FACC⁸, the mean percent release of lysozyme was significantly lower in CML PMNL as compared to that in normal cells (P < 0.001). There was no significant difference between the two after stimulation with PAF and LTB₄. The results indicate that the fMLP pathway is suppressed in CML granulocytes whereas PAF and LTB₄ pathways appear unaltered in these cells. We therefore also studied the kinetics of peptide-receptor interaction with a labelled hexapeptide fNLPNTL which binds to the fMLP receptor. Our results show that the number of fMLP receptors/cell is significantly lower in CML PMNL (P < 0.05) than in normal PMNL, while their affinity constants and dissociation constants were comparable. © 1996 Wiley-Liss, Inc.     

Respiratory membrane permeability and bronchial hyperreactivity in patients with stable asthma. Effects of therapy with inhaled steroids

In patients with stable asthma, we assayed plasma proteins in the bronchoalveolar lavage fluid to obtain information on plasma exudation into the airways. Fourteen nonsmoking patients with asthma who were in a stable period of their disease and eight nonsmoking healthy volunteers were studied. The ratios of the concentrations of albumin, ceruloplasmin (CP), and alpha-2-macroglobulin (A2M) between blood and epithelial lining fluid were calculated (cQalb, cQCP, and cQA2M). The cQalb was increased in the patients (Mann-Whitney U test, p less than 0.05). In 10 patients the bronchial hyperreactivity was assessed with histamine provocation tests. Significant relationships between the cQalb, cQCP, and cQA2M on the one hand and PC15 on the other hand were found (Spearman's rank correlation: r = -0.62, p less than 0.05; r = -0.61, p less than 0.05; r = -0.79, p less than 0.01, respectively). Fourteen patients were treated with two inhalations of 200 micrograms glucocorticosteroids per day in a 3-month prospective study. Three of them were excluded from further study because of an intercurrent exacerbation of asthmatic symptoms during therapy. In the 11 patients with stable asthma, the cQalb and cQA2M decreased after treatment with inhaled steroids (Wilcoxon's matched pairs signed rank test, p less than 0.03). Our results show that in patients with stable asthma, there is an increased plasma exudation into the airways, most likely caused by an increased respiratory membrane permeability. The plasma exudation correlated with the bronchial hyperreactivity to histamine, and it decreased after corticosteroid therapy.     

Long duration and high potency of antiexudative effects of formoterol in guinea-pig tracheobronchial airways.

Inflammatory stimulus-induced luminal exudation of plasma proteins is potentially pathogenic in asthma. This study of plasma exudation into tracheobronchial airways examines antiexudative effects (potency and duration of action) of two beta 2-agonists in anesthetized guinea pigs. The exudative response to airway provocations with bradykinin 1.25 x 10(-4) M (5 nmol) was determined in different groups of animals 10, 300, 450, and 600 min, respectively, after the mucosa had been treated topically with salbutamol 10(-6) to 10(-4) M (0.1 to 10 nmol), formoterol 10(-9) to 10(-7) M (0.1 to 10 pmol), or saline (control). Exuded plasma in tracheal lavage liquids was calculated from their contents of the plasma tracer, 125I-albumin, given intravenously 10 min before provocation with bradykinin. Salbutamol (1 and 10 nmol) and formoterol (1 and 10 pmol) promptly inhibited the mucosal exudation (p less than 0.001). Propranolol, 0.1 nmol, reduced (p less than 0.01) the antiexudative effects of both drugs. Only formoterol (1 and 10 pmol) maintained its effect at 300 min, abating gradually at 450 and 600 min. In a group of sensitized guinea pigs, formoterol (1 and 10 pmol) was demonstrated to inhibit also allergen-induced luminal exudation of plasma (p less than 0.001). It is suggested that an antiexudative action may contribute to the long duration of formoterol's antiasthma effect.