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PubMed1995

Hemocompatibility in hemodialysis and erythropoietin therapy.

Two studies designed to investigate the effect of recombinant human erythropoietin (rHuEPO) treatment of anemia in chronic dialysis patients on hemocompatibility were conducted. Study 1, whose main aim was to establish whether treatment with rHuEPO enhances coagulation activation during dialysis, included 15 patients before rHuEPO therapy at a mean hematocrit (HCT) of 22.3% and then during therapy at a HCT of 29.3%. The plasma concentrations of the thrombin-antithrombin III complex were not higher during rHuEPO therapy than before it when performing hemodialysis with a Cuprophan membrane. No significant difference was demonstrated either in the values of activated clotting times (Hemochron), thrombocyte or white blood cell counts (Coulter S+II), or in plasma C5a concentrations (ELISA) established during dialysis sessions before and during rHuEPO therapy. In Study 2, which focused primarily on the question of whether or not rHuEPO therapy increases thrombocyte activation during hemodialysis, 8 patients on chronic dialysis were examined both before therapy at a mean HCT value of 22.1% and during rHuEPO therapy at a HCT of 31.5%, invariably during dialysis with either a Cuprophan or polyacrylonitrile (AN69HF) membrane. The plasma concentrations of beta-thromboglobulin (ELISA) did not differ between the examinations made during rHuEPO and before rHuEPO therapy; however, statistically significant differences were found between dialysis sessions involving Cuprophan and AN69HF membranes. No significant difference between examination before and during rHuEPO was demonstrated in activated clotting time nor thrombocyte and white blood cell counts in this study either. The authors conclude that rHuEPO therapy does not enhance coagulation activation during hemodialysis, does not have an effect on thrombocyte activation, and does not influence complement activation and changes in white blood cell counts.

Acrylic Resins↗
PubMed2000

Inflammatory response after coronary revascularization with or without cardiopulmonary bypass.

BACKGROUND: We sought to investigate the effect of multiple coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (CPB) on the perioperative inflammatory response. METHODS: Sixty patients undergoing CABG were randomly assigned to one of two groups: (A) on pump with conventional CPB and cardioplegic arrest, and (B) off pump on the beating heart. Serum samples were collected for estimation of neutrophil elastase, interleukin 8 (IL-8), C3a, and C5a preoperatively and at 1, 4, 12, and 24 hours postoperatively. Furthermore, white blood cell (WBC), neutrophil, and monocyte counts were carried out preoperatively and at 1, 12, 36 and 60 hours postoperatively. Overall incidence of infection and perioperative clinical outcome were also recorded. RESULTS: The groups were similar in terms of age, weight, gender ratio, extent of coronary disease, left ventricular function, and number of grafts per patient. Neutrophil elastase concentration peaked early after CPB in the on-pump group, with a decline with time. Repeated-measures analysis of variance between groups and comparisons at each time point (modified Bonferroni) showed elastase concentrations were significantly higher in the on-pump than the off-pump group (both p < 0.0001). IL-8 increased significantly after surgery in the on-pump group, with no decline during the observation period (p = 0.01 vs off pump). C3a and C5a rose early after surgery in both groups when compared with baseline values. Postoperative WBC, neutrophil, and monocyte counts were significantly higher in the on-pump than the off-pump group (p < 0.01). Finally, the incidence of postoperative overall infections was significantly higher in the on-pump group (p < 0.0001 vs off pump). CONCLUSIONS: CABG on the beating heart is associated with a significant reduction in inflammatory response and postoperative infection when compared with conventional revascularization with CPB and cardioplegic arrest.

Aged↗
PubMed2000

Major trauma enhances store-operated calcium influx in human neutrophils.

PURPOSE: Chemotaxins from inflammatory sites prime or activate neutrophils (PMN) by using cytosolic calcium ([Ca2+]i) fluxes as second messengers. [Ca2+]i can be mobilized rapidly by receptor-mediated entry or store-release, or more slowly by store-operated calcium influx (SOCI). We studied [Ca2+]i mobilization by chemotaxins and how trauma impacts the calcium entry mechanisms used by chemotaxins. METHODS: [Ca2+]i flux was studied by spectrofluorometry. The contributions of early and late [Ca2+]i currents to net calcium flux were compared after stimulation by more potent (fMLP, C5a, PAF) or less potent (IL-8, GRO-alpha, and LTB4) agonists. Store operated [Ca2+]i mobilization was reflected by the ratio of area under the [Ca2+]i efflux curve to peak [Ca2+]i (efflux curve). PMN from trauma patients (ISS > 25) and pair-matched volunteer (n = 7 pairs) were then primed and stimulated with thapsigargin to compare cell calcium stores and SOCI. RESULTS: Late [Ca2+]i mobilization made more important contributions to fMLP, PAF, and C5a signals than to IL-8, GRO-alpha, or LTB4 (p < 0.01 all comparisons). Calcium stores and store release were only marginally lower after injury (p = not significant), but trauma PMN showed far higher [Ca2+]i influx after thapsigargin (p = 0.007), and greater net SOCI (p = 0.034). CONCLUSIONS: SOCI may play an important role in PMN activation, and trauma increases PMN SOCI. Prolonged elevations of [Ca2+]i due to enhanced SOCI may alter stimulus-response coupling to chemotaxins and contribute to PMN dysfunction after injury.

Adult↗
PubMed1992

Preferential suppression of delayed-type hypersensitivity by L-156,602, a C5a receptor antagonist.

In the course of our screening for in vivo immunomodulating substances in which sheep red blood cells (SRBC) and heat-killed Brucella abortus cells (thymus dependent and independent antigens, respectively) for antibody production assays, and trinitrobenzene sulfonic acid (TNBS) for delayed-type hypersensitivity (DTH) assay were adopted as antigens, we detected a DTH-specific suppressive activity. The producing organism was isolated from a soil sample collected in Ushiku City, Ibaraki, Japan and identified with Streptomyces sp. A1502 (FERM P-12448). The active component was identified with L-156,602, a C5a receptor antagonist. L-156,602 suppressed both TNBS-induced and TNP-SRBC-induced DTH while it enhanced antibody production against SRBC, Brucella abortus, and TNP-SRBC. L-156,602 significantly suppressed DTH induced by direct injection of type 1 helper T cells and its relevant antigen into hind-footpads, indicating that the efferent phase of DTH was affected by L-156,602. The results demonstrated that L-156,602 preferentially suppressed the DTH response.

Adjuvants, Immunologic↗
PubMed1995

Biological characteristics of chronic eosinophilic leukemia cells with a t(2;5)(p23;q35) translocation.

We studied the biological features of eosinophils in a patient with chronic eosinophilic leukemia and a unique t(2:5)(p23;q35) translocation. Microscopic and cytochemical studies revealed no particular abnormalities, although more than 90% of the peripheral eosinophils had a density lighter than 1.080 g/ml. Clonogenic assay disclosed that myeloid progenitor cells possessed the translocation, although in vitro eosinophilopoiesis seemed normal, and there were also hematopoietic cells with a normal karyotype. In a surface marker study, EG1 was positive on 34.0% of the eosinophils, while EG2 positivity was only 0.5%. Eosinophilopoietic growth factors and adhesion molecules were virtually absent with the exception of GM-CSF and CD11b. Functional studies showed that chemotaxis for C5a was normal, although that for IL-2 or FMLP was attenuated. In addition, leukotriene C4 production was decreased while O2- production was intact. These findings indicated that our patient's eosinophils were not in an activated state despite their extreme hypodensity, and suggested that the leukemic eosinophils had slight defects of cellular function. These characteristics may have saved the patient from the multiple organ damage which occurs in typical hypereosinophilic syndrome.

Adult↗
PubMed1990

Identification of an IgA inhibitor of neutrophil chemotaxis and its membrane target for the metabolic burst.

Affinity-purified IgA from the serum of an 8-year-old boy with a 5-year history of recurrent facial nodules, intermittent neutropenia and elevated immunoglobulin levels, inhibited the chemotaxis of polymorphonuclear neutrophils (PMN) from both patient and normal adults. Preincubation of normal PMN with IgA from the patient's serum (0.5 mg/ml) inhibited chemotaxis to C5a and to the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) by 80%, while IgA or IgG from pooled human serum and IgG from the patient were without effect. Normal PMN chemotaxis was restored after IgA depletion of the patient's serum by affinity chromatography. The patient's IgA, but not IgA from pooled human serum, bound specifically to normal PMN by its antigen-binding sites and recognized a 62,000 MW membrane protein on normal neutrophils, which was distinct from the FMLP receptor, the C5a receptor, or the Fca receptor. Attachment of the patient's IgA to the 62,000 MW protein activated intracellular oxidative metabolism on a parity with phorbol myristate acetate (PMA) and resulted in a significant up-regulation of membrane receptors for FMLP. After the binding of patient (Pt) IgA, normal neutrophils were rendered significantly less responsive to subsequent stimulation with phorbol esters. These results characterize a novel mechanism of chemotactic inhibition by serum IgA and also identify a neutrophil membrane protein that is linked to intracellular oxidative metabolism.

Chemotaxis, Leukocyte↗
PubMed2003

Involvement of RhoA and Rho kinase in neutrophil-stimulated endothelial hyperpermeability.

Neutrophil-induced microvascular leakage is an early event in ischemic and inflammatory heart diseases. The specific signaling paradigm by which neutrophils increase microvascular permeability is not yet established. We investigated whether the small GTPase RhoA and its downstream effector Rho kinase mediate neutrophil-stimulated endothelial hyperpermeability. We assessed the effect of neutrophils on Rho activity in bovine coronary venular endothelial cells (CVEC) with a Rho-GTP pull-down assay. Permeability to FITC-albumin was evaluated using CVEC monolayers. We then tested the role of Rho kinase in the permeability response to neutrophils using two structurally distinct pharmacological inhibitors: Y-27632 and HA-1077. Furthermore, neutrophil-stimulated changes in endothelial F-actin organization were examined with fluorescence microscopy. The results show that C5a-activated neutrophils induced an increase in permeability coupled with RhoA activation in CVEC. Inhibition of Rho kinase with either Y-27632 or HA-1077 attenuated the hyperpermeability response. Rho kinase inhibition also attenuated increases in permeability stimulated by the neutrophil supernatant. In addition, activated neutrophils caused actin stress fiber formation in CVEC, which was diminished by either Y-27632 or HA-1077. These findings suggest that RhoA and Rho kinase are involved in the mediation of neutrophil-induced endothelial actin reorganization and barrier dysfunction.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed2003

Matrix metalloproteinase-9 release from human leukocytes.

Although proteinases are thought to contribute to the pathogenesis of bronchial asthma and COPD, the mechanism of proteinase release from inflammatory cells has not been thoroughly clarified. We examined matrix metalloproteinase (MMP-9) release from human leukocytes using soluble agonists such as C5a, FMLP, and PAF. Mononuclear cells, neutrophils, and eosinophils isolated from human leukocytes were incubated with C5a, FMLP, or PAF for 20 min. MMP-9 in supernatants was measured by ELISA. Among mononuclear cells, neutrophils, and eosinophils, MMP-9 was released mainly from neutrophils. FMLP was the most effective stimulus of MMP-9 release from neutrophils among three agonists: C5a, FMLP, and PAF. GM-CSF clearly enhanced FMLP-induced MMP-9 release. Pretreatment of neutrophils with pertussis toxin (PTX) resulted in the inhibition of FMLP-induced MMP-9 release, indicating the contribution of PTX-sensitive G-proteins to intracellular signal transduction in FMLP-induced MMP-9 release. These results suggest that neutrophils release large amounts of MMP-9 in response to FMLP, which is a bacterial product analogue. It cannot be excluded that MMP-9 released from neutrophils may be involved in the pathogenesis of bronchial asthma and COPD.

Asthma↗
PubMed1990

Recombinant C5a enhances interleukin 1 and tumor necrosis factor release by lipopolysaccharide-stimulated monocytes and macrophages.

Lipopolysaccharide (LPS) is a potent inducer of interleukin 1 (IL 1) synthesis and release, and of tumor necrosis factor (TNF) secretion. Many signals can enhance the LPS-induced production of these cytokines. We have previously observed that addition of low amounts of normal human serum to the culture medium enhances IL 1 production. Among serum factors, anaphylatoxins C3a and C5a and/or their desArg derivatives have been shown to enhance LPS-induced IL 1 and TNF production. However, the capacity of natural anaphylatoxins to induce by themselves the production of cytokines remains a controversial issue. We have investigated the capacity of human recombinant C5a (hrC5a) to induce IL 1 and TNF production. Despite its lack of direct triggering, hrC5a was able to act synergistically with LPS, leading to higher IL 1 and TNF release by human monocytes and mouse peritoneal macrophages. As assessed by the comitogenic assay, hrC5a increased IL 1 release, whereas cell-associated IL 1 activity was not significantly modified. Measurement by enzyme-linked immunosorbent assay of human IL 1 beta led to similar conclusions, whereas measurement of IL 1 alpha by radioimmunoassay indicated, in addition, an increase in intracellular IL 1 alpha.

Animals↗
PubMed1986

Polymorphonuclear leukocyte-dependent plasma leakage in the rabbit skin is enhanced or inhibited by prostacyclin, depending on the route of administration.

Experiments were designed to test for possible differing modulatory effects of either intravascular or extravascular prostaglandins (PGs) on local edema induced by intradermally injected inflammatory mediators in the rabbit. Local extravascular PGI2, PGE2 and 15-methyl-PGE1, with similar potencies, had a marked potentiating effect on local edema induced by C5a des Arg. Local extravascular PGI2 also potentiated edema when tested with leukotriene B4 (LTB4), bradykinin, and histamine. However, intravenously infused PGI2 at 50 ng/kg/min reversed the enhancing effect of local extravascular PGI2. At this dose the attenuating effect of PGI2 was selective for the polymorphonuclear (PMN) leukocyte-dependent edema induced by C5a des Arg and LTB4, but had no effect on edema induced by the nonchemoattractants histamine and bradykinin. Similarly, edema induced by N-formyl-methionyl-leucyl-phenylalanine was suppressed, but not that induced by platelet activating factor. 15-Methyl-PGE1, at 300 ng/kg administered systemically (subcutaneously), also selectively suppressed PMN-dependent edema. However, at higher doses of 3 and 60 micrograms/kg attenuation was nonselective and associated with a fall in systemic arterial blood pressure. These experiments demonstrate that the site of PG generation and action is an important determinant of its influence on edema formation.

Alprostadil↗
PubMed1993

VLA-4 integrin can mediate CD11/CD18-independent transendothelial migration of human monocytes.

The migration of human monocytes across unactivated and activated human umbilical vein endothelium (HUVE) in response to chemotactic factors was studied, and the adhesion molecules involved were characterized. Migration of blood monocytes or U937 cell line-derived monocytes across unactivated HUVE induced by C5a, was partially inhibited (by 75%) by mAbs (R15.7 or 60.3) to CD18 of the CD11/CD18 complex on the monocyte. However, when the HUVE was pretreated for 5 h with IL-1 alpha (0.1 ng/ml), TNF-alpha (100 U/ml), or LPS (1 ng/ml), migration induced by C5a was no longer inhibited; i.e., migration became CD18 independent. The monocyte CD18-independent migration was completely blocked by mAbs against alpha 4 or beta 1 integrin chains of VLA-4. This migration was also partially inhibited by mAbs against vascular cell adhesion molecule-1 (VCAM-1), a major counter-receptor on HUVE for VLA-4, but not by mAbs to E-selectin or intercellular adhesion molecule-1. The significant CD18-independent migration across "unactivated" HUVE was also inhibited by mAbs against alpha 4 or beta 1 chains of VLA-4, although mAbs against VCAM-1 did not inhibit under these conditions. Finally, considerable VLA-4-dependent transendothelial migration to C5a was also observed with monocytes from a patient with CD18 deficiency (leukocyte adhesion deficiency). These results suggest that (a) there is a major CD18-independent component in monocyte chemotactic factor-dependent migration across activated and unactivated endothelium; (b) that VLA-4 integrin on the monocyte has a major role in this migration; and (c) that VCAM-1 on activated endothelium functions as a counter-receptor in this process, but other ligands for VLA-4, especially on unactivated endothelium, may also be involved.

Antibodies, Monoclonal↗
PubMed1991

Chemotactic inhibitors in sera of patients with neoplastic disease.

Our objective was to define the functional characteristics of chemotactic inhibitors in sera of patients with various neoplastic diseases. Fifty-nine patients were studied: lung cancer (15), breast cancer (11), lymphoma (20), leukemia (13). Chemotaxis and random motility were measured using a modified agarose technique with C5a and a bacterial filtrate of E. coli as the chemoattractants. Two types of inhibitors were found: chemotactic factor inhibitors and cell-directed inhibitors. The type of inhibitor as well as the specificity of the inhibitor for the chemoattractant (C5a or bacterial filtrate) varied depending upon the underlying neoplasm. Cell-directed inhibitors were reversible and none of the inhibitors affected random motility. Contrary to previous reports, the chemotactic factor inhibitors were heat-stable (p less than 0.001). Morphometric analysis of inhibited and non-inhibited cells using scanning electron photomicrographs showed a significant alteration in shape of the inhibited cells (p less than 0.003). The results indicate greater heterogeneity of the chemotactic inhibitors than was previously thought, as well as a tumour-dependent specificity of the inhibitors for the chemoattractants.

Breast Neoplasms↗
PubMedDate not supplied

[Current aspects of chemotaxis of phagocytic cells].

Phagocytic cells, the first host defence against microbial attack, are remarkably mobile; they can move very rapidly to the infectious or inflammatory site. They migrate toward a chemotactic factor: C5a, lymphokines, bacterial products, leukotriene B4, etc. The binding of the chemotactic factor to its specific receptor on the cell leads to an activation of the phagocytic cell: the electric potential of the membrane changes, ionic fluxes and free calcium rate increase, arachidonic acid metabolites are produced, cyclic nucleotides are activated. This produces a change in shape, a polarization of the cell and, after cytoskeleton reorganization, migration of the cell towards the chemotactic factor. A constitutional or acquired abnormality of one of these steps induces a defect of chemotaxis for the phagocytic cells and severe infections.

Bacterial Proteins↗
PubMed1996

Monoclonal Lym-1 antibody-dependent lysis of B-lymphoblastoid tumor targets by human complement and cytokinine-exposed mononuclear and neutrophilic polymorphonuclear leukocytes.

Lym-1 is a murine IgG2a monoclonal antibody that recognizes a polymorphic variant of HLA-DR antigens on malignant B cells, with minimal cross-reactivity with normal tissues. Because it can be safely administered in vivo, a detailed knowledge of its ability to recruit and trigger the antitumor immune effector systems is required to optimize potential serotherapeutic approaches in B-lymphoma patients. By using Raji cells as a model of B-lymphoma targets, we found that Lym-1 activates complement-mediated lysis efficiently. Moreover, Lym-1 was capable of triggering the antibody-dependent cellular cytolysis (ADCC) by peripheral blood mononuclear cells (MNCs). On the contrary, it failed to trigger neutrophilic polymorphonuclear leukocyte (PMN)-mediated ADCC activity. In an attempt to enhance Lym-1 ADCC by MNCs and PMNs, nine biologic response modifiers were tested. MNC-mediated Lym-1 ADCC was significantly stimulated by interleukin-2 (IL-2) and unaffected by other mediators, including gamma-interferon (gamma-IFN), tumor necrosis factor a (TNFalpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF). On the other hand, PMN-mediated Lym-1 ADCC was induced or significantly augmented by various cytokines, such as GM-CSF, TNFalpha, and gamma-IFN, and chemotaxins, such as formyl peptides (FMLP), complement fragment C5a, and IL-8. Both MNC- and PMN-mediated ADCC was unaffected by granulocyte colony-stimulating factor (G- CSF) and insulin-like growth factor-1 (IGF-1). Finally, only GM-CSF and TNFalpha augmented the number of PMNs actually engaged in the binding of Raji target cells. The findings presented here, in particular those showing stimulatory activity of biologic response modifiers, may inspire new attempts for developing Lym-1 antibody-based approaches to the therapy of B lymphomas.

Adult↗
PubMed1996

Regulation of activation of bovine neutrophils by aggregated immunoglobulin G.

OBJECTIVES: To investigate the role of extracellular Ca2+ and Mg2+ in aggregated IgG (aIgG)-mediated cellular activation, and to determine how aIgG-induced activation is coupled to Ca2+ homeostasis in bovine neutrophils. SAMPLE POPULATION: 4 clinically normal, lactating Holstein cows, in their second lactation, which ranged between 60 and 150 days. PROCEDURE: aIgG was prepared by heating bovine IgG, and C5a was obtained by activating fetal bovine serum with zymosan. Luminol-amplified chemiluminescence (CL) of isolated neutrophils was measured in the presence of aIgG or phorbol 12-myristate 13-acetate (PMA). The reaction mixture contained either Hanks' balanced salt solution or Ca(2+)- and Mg(2+)-free Hanks' balanced salt solution. Binding of aIgG to neutrophils was measured by flow cytometry after incubation with fluorescein isothiocyanate-conjugated second antibody. Intracellular-free concentration [Ca2+]i was measured in a fluorescence spectrofluorometer after incubation of neutrophils, loaded with the fluorescent dye fura-2 acetoxymethyl ester, with either aIgG or C5a. RESULTS: In a Ca(2+)- and Mg(2+)-containing reaction mixture, aIgG induced strong CL responses, whereas removal of extracellular divalent cations almost abolished the respiratory burst activity. The CL emission on stimulation with PMA was independent of extracellular Ca2+ and Mg2+. Examination of cells by flow cytometry after incubation with aIgG indicated that the binding of aIgG was identical in the presence and absence of extracellular Ca2+ and Mg2+. No increase in [Ca2+]i was seen in fura-2 acetoxymethylester-loaded neutrophils after stimulation with aIgG. C5a induced a typical transient increase in [Ca2+]i. CONCLUSIONS: aIgG-induced activation of bovine neutrophils is highly dependent on presence of extracellular divalent cations. This dependency is not caused by the need of divalent cations for binding of aIgG by neutrophils or because the influx of Ca2+ from the extracellular space is an integral component of aIgG-mediated activation pathway. Because need for extracellular Ca2+ and Mg2+ could be partially circumvented by pretreating neutrophils with PMA, it is possible that this activation pathway may involve a protein kinase C, which is not directly coupled to receptors for aIgG.

Animals↗
PubMed1992

Vascular occlusion of the retina: an experimental model. I. Leukocyte aggregates.

A new technique was developed to study the pathogenesis of retinal arteriolar occlusion in the pig. Using a catheter with its tip in front of the exit of the ophthalmic artery, autologous microparticles could be injected directly into the retinal arterial system. These microparticles were C5a-des-Arg stimulated leukocytes, which were aggregated to pellets of different sizes ranging from 0.26 to 1.0 mm. For better adhesion of the aggregates to the endothelium, endothelial damage was induced by the injection of additional substances, including methomidate and endothelial antibodies. In a further series of experiments systemic hypoxemic conditions were created over several hours prior to injection of the leukocyte aggregates. This resulted in cotton-wool spots and arterial branch occlusions with retinal edema. Furthermore, retinal hemorrhages occurred. This experimental model seems to be appropriate for mimicking retinal arteriolar occlusion syndromes.

Animals↗
PubMed1998

Chemotaxins C5a and fMLP induce release of calprotectin (leucocyte L1 protein) from polymorphonuclear cells in vitro.

AIMS: To determine whether the chemotaxins C5a and formyl peptide (fMLP) can stimulate the release of calprotectin, the major leucocyte protein of polymorphonuclear neutrophils (PMN). METHODS: A dose response curve for the uptake of 125I labelled rC5a and fMLP in PMN was determined by radioimmunoassay. The unlabelled chemotaxins were then incubated with PMN and the concentration of calprotectin in PMN lysates and supernatants was measured by an enzyme immunoassay. RESULTS: Both rC5a and fMLP induced release of calprotectin from PMN in a dose dependent manner as determined by a reduction in intracellular calprotectin concentration. A minimum of approximately 10% of total PMN calprotectin was retained at concentrations of 10-100 nM of rC5a and 0.1-10.0 nM of fMLP. Antibodies to C5a reduced the rC5a mediated release of calprotectin, and the fMLP antagonist N-t-Boc-MLP inhibited the fMLP induced calprotectin release. Because receptors for rC5a (CD88) and fMLP are G protein coupled and thought to be pertussis toxin sensitive, PMN were incubated with this toxin before the experiments. The toxin was found to reduce uptake of rC5a by the cells and to inhibit rC5a and fMLP mediated calprotectin release. CONCLUSIONS: rC5a and fMLP mediate release of calprotectin from PMN in vitro. This effect might be important during human infections in vivo.

Antigens, Surface↗
PubMed2000

Role of carbohydrate antigens sialyl Lewis (a) (CA19-9) in bronchoalveolar lavage in patients with pulmonary fibrosis.

BACKGROUND: It has been reported that carbohydrate antigen sialyl Lewis (a) (CA19-9) levels are elevated in serum as well as in bronchoalveolar lavage fluid (BALF) of patients with pulmonary fibrosis. However, the biological significance of CA19-9 is unclear. OBJECTIVE: The purpose of the present study was to evaluate correlations between CA19-9 levels in BALF and several biochemical as well as clinical parameters in patients with pulmonary fibrosis. In addition, biological functions of CA19-9 were also examined. METHODS: We studied 24 patients with a diagnosis of pulmonary fibrosis: 16 with idiopathic pulmonary fibrosis (IPF) and 8 with pulmonary fibrosis associated with a collagen vascular disorder (PF-CVD). In BALF, carbohydrate antigens sialyl Lewis (a) (CA19-9), elastase: alpha(1)-proteinase inhibitor complex (E-PI), hepatocyte growth factor (HGF), LDH, IgG, IgA, albumin, and cell differentiation were measured. We also evaluated the effects of CA19-9 on neutrophil functions. RESULTS: CA19-9/albumin levels in BALF significantly correlated with HGF/albumin, elastase/albumin, LDH/albumin, total number of alveolar macrophages, and total number of neutrophils. Purified CA19-9 had a chemotactic activity for neutrophils. In addition, neutrophil chemotactic activity to C5a, fMLP, and interleukin 8 was significantly stimulated after incubation with purified CA19-9. Furthermore, CA19-9 increased the expression of CD15s on neutrophils. CONCLUSIONS: Our data demonstrated (i) CA19-9 in BALF correlated with other markers of inflammation in pulmonary fibrosis, and (ii) CA19-9 can modify neutrophil functions. These results suggest that CA19-9 may play a role in the process of lung injury in patients with pulmonary fibrosis.

Adult↗