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PubMed1991

Neutrophils can generate their activator neutrophil-activating peptide 2 by proteolytic cleavage of platelet-derived connective tissue-activating peptide III.

We have investigated the conditions that lead to the generation of the neutrophil-activating peptide 2 (NAP-2) from its precursor, the platelet-derived connective tissue-activating peptide III (CTAP-III). Lysed platelets were found to contain predominantly CTAP-III in the cytosolic fraction, but further truncated derivatives, among these NAP-2, occurred tightly bound to the membrane fraction of fresh platelets. NAP-2 biological activity, as measured by the induction of enzyme release in human neutrophils [polymorphonuclear leukocytes (PMN)] was released by stimulated platelets to a low degree. Much higher activities were formed in the presence of peripheral blood leukocytes. Coincubation of CTAP-III with PMN resulted in the almost complete conversion of the precursor to NAP-2, as did incubation of CTAP-III with PMN-conditioned medium. In both situations, the generation of NAP-2 could be prevented by serine-protease inhibitor phenylmethylsulfonyl fluoride but not by inhibitors specific for Ca(2+)-dependent or thiol proteases. From several PMN-derived proteases tested, only cathepsin G had the capacity to cleave CTAP-III into NAP-2 with high specificity and in a relatively short period of time (30 min). Our data indicate that NAP-2, released by platelets in small quantities, could cause PMN to enter into a positive feedback cycle by initiating the secretion of serine proteases, which in turn could convert platelet-derived CTAP-III into biologically active NAP-2.

Amino Acid Sequence↗
PubMed2004

Neutrophil degranulation: therapeutic targets in [NTP]O mediated neutrophil degranulation.

Extracellular nucleotide-induced stimulation and activation of peripheral blood neutrophil and subsequent degranulation plays a critical role in immediate type hypersensitivity reaction and other inflammatory diseases. The extracellular nucleotides stimulate a P2Y receptor(s) on human PMN with the pharmacological profile similar to that of the P2Y2 receptor. Based on a recent proposal on the molecular mechanism of [NTP]O-induced neutrophil degranulation, a scheme identifying the therapeutic targets, is suggested with potential avenues for attenuating PMN degranulation.

Cell Degranulation↗
PubMed2005

Detection of individual human neutrophil alpha-defensins (human neutrophil peptides 1, 2 and 3) in unfractionated gingival crevicular fluid--a MALDI-MS approach.

The role of antimicrobial peptides is particularly important in the oral cavity where there is constant challenge by microorganisms. The alpha-defensins are a group of cationic peptides that comprise 30-50% of the total protein in azurophilic granules of human neutrophils. They include the human neutrophil peptides (HNP) 1, 2 and 3 which have almost identical amino acid sequences but differ in their biological activities. The amino acid sequence similarities of the defensins have made it difficult to unequivocally determine the presence of individual defensins using antibody-based techniques. However, by virtue of their cationic nature we postulated that the defensins would fly particularly well in mass spectrometry and that this characteristic would allow facile identification of individual HNPs in unfractionated gingival crevicular fluid (GCF) from periodontitis patients and healthy controls. Although there was variability in levels of defensins detected in periodontal health and disease, HNP-1 was always identified as the major peak in the triad and HNP-3 as the minor peak, lending support to the hypothesis that HNP-2 may arise by post-translational proteoyltic cleavage of HNP-3 rather than HNP-1. The finding that the defensins were more abundant in a higher proportion of the healthy sites studied could be linked to a more intact defensin barrier in periodontal health.

Adult↗
PubMed2003

Overproduction of neutrophil radical oxygen species correlates with negative symptoms in schizophrenic patients: parallel studies on neutrophil chemotaxis, superoxide production and bactericidal activity.

Defective neutrophil function in schizophrenic patients has recently been reported. There are several lines of evidence to support the contribution of oxygen free radicals in schizophrenia, including increased lipid peroxidation, fatty acids and alterations in blood levels of anti-oxidant enzymes. Eighteen schizophrenic patients (DSM-IV) and 15 healthy controls were studied. Neutrophil chemotaxis, superoxide production and bactericidal activity were investigated. A statistically significant increase of superoxide anion release was found in schizophrenic patients compared with controls (mean+/-S.E.M., patients: 6.89+/-0.30 nmol O2-/10(6) cells/min, controls: 5.13+/-0.55 nmol O2-/10(6) cells/min). Moreover, a significant positive correlation between superoxide production and negative symptoms as assessed by the Positive and Negative Syndrome Scale was demonstrated. No differences were detected in chemotaxis and phagocytosis between schizophrenic patients and healthy controls. The present findings of a positive correlation between superoxide generation and negative symptoms in schizophrenic patients support the hypothesis that superoxide anion may participate in the pathogenesis of schizophrenia, as an excess of free radicals could contribute to the deterioration phase of the disease. Further studies are required to establish the role of oxidative stress in the ethiopathogenesis of schizophrenia.

Adult↗
PubMed1991

Chemical synthesis, purification, and characterization of two inflammatory proteins, neutrophil activating peptide 1 (interleukin-8) and neutrophil activating peptide.

Two recently identified pro-inflammatory proteins, namely, neutrophil activating peptide 1 (NAP-1) [also termed interleukin-8 (IL-8)] and NAP-2, were chemically synthesized, purified, and characterized. The fully protected NAP-1/IL-8 (72 residues) and NAP-2 (70 residues) peptide chains were assembled by automated solid-phase methods with average stepwise yields of 99.5 and 99.3%, resulting in overall chain assembly yields of 70 and 62%, respectively. Deprotection resulted in crude products, which were allowed to fold by air oxidation, and were purified by two cycles of reverse-phase high-pressure liquid chromatography, yielding 27 mg of NAP-1/IL-8 and 22 mg of NAP-2. Purity was established by reverse-phase high-pressure liquid chromatography and isoelectric focusing, and the primary structures of the purified products were verified by using mass spectrometry and Edman sequencing methods. Synthetic and recombinant NAP-1/IL-8 were equally active on human neutrophil granulocytes as determined by measuring the induction of cytosolic free calcium, elastase release, and chemotaxis. Synthetic NAP-2 was equivalent to purified natural NAP-2 in the elastase release and calcium mobilization assays, but it was consistently less potent (3-5-fold) as a stimulus of chemotaxis, perhaps indicative of additional chemotactic components in the natural preparation. The results indicate that by chemical synthesis these cytokines can be obtained in purity and quantities suitable for further structural analysis, as well as functional studies both in vivo and in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

Synthesis of peptidyl fluoromethyl ketones and peptidyl alpha-keto esters as inhibitors of porcine pancreatic elastase, human neutrophil elastase, and rat and human neutrophil cathepsin G.

Comparison of MeO-Suc-Val-Pro-Phe-CO2Me (29) and MeO-Suc-Ala-Ala-Pro-Phe- CO2Me (25) with their corresponding trifluoromethyl ketones 9a and 9b, respectively, in rat and human neutrophil cathepsin G assays showed the alpha-keto esters to be more potent inhibitors. Likewise, Ac-Pro-Ala-Pro-Ala-CO2Me (21) was more potent than its corresponding trifluoromethyl ketone (9c) in both porcine pancreatic elastase and human neutrophil elastase assays. Within a set of Ala-Ala-Pro-Val-CF3 elastase inhibitors, the carbobenzyloxy (Cbz) N-protecting group conferred greater potency as a P5 site recognition unit for elastase than did dansyl, methoxysuccinyl, or tert-butyloxycarbonyl. Initial inhibition of elastase was greater when trifluoromethyl ketone 9f was added from a stock solution of dimethyl sulfoxide than when it had been buffer-equilibrated prior to assay, which suggests that the nonhydrated ketone is the more effective form of the inhibitor. The most potent elastase inhibitor we report is Na-(Ad-SO2)-N epsilon-(MeO-Suc)Lys-Pro-Val-CF3 (16) which has a Ki of 0.58 nM.

Amino Acid Sequence↗
PubMed2001

Activity of the leukocyte NADPH oxidase in whole neutrophils and cell-free neutrophil preparations stimulated with long-chain polyunsaturated fatty acids.

Fish oils are known for their anti-inflammatory effects. In this paper we investigated the influence of eicosapentaenoic acid and docosahexaenoic acid (omega-3 fatty acids), as well as docosapentaenoic acid, a metabolic product of omega-3 fatty acid metabolism, on O2(-)-production catalyzed by the NADPH oxidase in whole neutrophils and in a cell-free system consisting of neutrophil membranes and cytosol. As a standard we used arachidonic acid (an omega-6 fatty acid) found in a high proportion in the Western diet, and known as an effective activator of the oxidase in both systems. Our data show that with omega-3 fatty acids, the O2(-)-production in both systems is reduced as compared to the effect of arachidonic acid. The effects are more pronounced with increasing carbon chain length and increasing numbers of double bonds. Our results suggest another mechanism besides the inhibition of eicosanoid and cytokine production to explain the beneficial effects of fish oils in reducing inflammation.

Adult↗
PubMed2001

Neutrophil priming and apoptosis in anti-neutrophil cytoplasmic autoantibody-associated vasculitis.

BACKGROUND: Interactions between anti-neutrophil cytoplasmic autoantibody (ANCA) and primed neutrophils (PMNs) may be central to the pathogenesis of primary small vessel vasculitis. PMNs from patients are primed, expressing proteinase 3 (PR3) on the cell surface, which permits interaction with ANCA. In vitro ANCA activates primed PMN to degranulate and generate a respiratory burst. Resultant reactive oxygen species are important in triggering apoptosis, but the fate of PMN in ANCA-associated vasculitis is unknown. Failure to remove apoptotic PMN in a nonphlogistic manner may sustain the inflammatory response. METHODS: PMNs from patients or controls were isolated, and the basal production of superoxide was measured by the superoxide dismutase-inhibitable reduction of ferricytochrome C. ANCA antigen expression on apoptotic PMN was assessed at 0, 12, and 18 hours by flow cytometry using dual staining with FITC-conjugated annexin V and PE-conjugated anti-murine IgG against monoclonal ANCA. Apoptosis was also assessed by morphology. In further studies, apoptotic PMNs were opsonized with monoclonal anti-myeloperoxidase (MPO) or anti-proteinase-3 (PR3) or irrelevant isotype-matched IgG (N IgG) and phagocytosis by macrophages was measured using interaction assays. Cytokines interleukin-8 (IL-8) and interleukin-1 were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Proteinase-3 expression (active 63.04 +/- 5.6% of total number of cells, remission 51.47 +/- 7.9% of total number of cells, control 17.7 +/- 4.7% of total number of cells, P < 0.05) and basal superoxide production (active 6.9 +/- 0.8 nmol/L x 10(6) cells, remission 5.15 +/- 0.4 nmol/L/10(6) cells, control 3.63 +/- 0.3 nmol/L/10(6) cells, P < 0.001) were significantly greater with freshly isolated PMN from patients than controls. PR3 expression and superoxide generation were positively correlated. PMN from patients with active disease became apoptotic at a greater rate than those of controls (at 18 hours, patients 72.3 +/- 3.9% apoptosis, controls 53.2 +/- 2.7% apoptosis, P < 0.05). PR3 and MPO expression were significantly greater on PMN isolated from patients at 12 and 18 hours. Opsonization of apoptotic PMN with ANCA significantly enhanced recognition and phagocytosis by scavenger macrophages (anti-MPO 88.95 +/- 6.27, anti-PR3 93.98 +/- 4.90, N IgG 44.89 +/- 3.44, P < 0.01) with increased secretion of IL-1 (anti-PR3 34.73 +/- 6.8 pg/mL, anti-MPO 42.01 +/- 12.3 pg/mL, N IgG 8.04 +/- 6.3 pg/mL, P < 0.05) and IL-8 (anti-PR3 8.97 +/- 0.93 ng/mL, anti-MPO 8.45 +/- 1.46 ng/mL, N IgG 0.96 +/- 0.15 ng/mL, P < 0.01). CONCLUSION: In vivo circulating PMNs are primed as assessed by PR3 expression and basal superoxide production, thereby enhancing their inflammatory potential. These PMNs undergo apoptosis more readily, at which times they express PR3 and MPO on their surface. These antigens may then provide targets for ANCA. Opsonization of apoptotic PMN will enhance clearance by macrophages but will also trigger the release of pro-inflammatory cytokines that may contribute to chronic inflammation.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1998

Neutrophil transfusions: kinetics and functions of neutrophils mobilized with granulocyte-colony-stimulating factor and dexamethasone.

BACKGROUND: The collection of adequate numbers of neutrophils (polymorphonuclear leukocytes, PMNs) from normal donors has long hampered the development of neutrophil transfusion therapy. The stimulation of donors with granulocyte-colony-stimulating factor (G-CSF) plus dexamethasone is a promising way of improving PMN collections. STUDY DESIGN AND METHODS: Sixteen normal subjects received G-CSF (600 micrograms subcutaneously) and dexamethasone (8 mg by mouth) 12 hours before leukapheresis. Measurements included PMN morphology, immunophenotype analysis, chemiluminescence, bactericidal activity, in vivo kinetics, and adverse effects. RESULTS: A mean of 77.4 +/- 6.4 x 10(9) PMNs was collected with each leukapheresis; 14 percent were bands. PMNs had increased surface expression of CD11b, CD18, CD14, CD32, and CD64. Bactericidal capacity against Staphylococcus aureus was normal. Inducible respiratory burst was maintained, although the responses to some agonists were diminished. Returned leukapheresis cells labeled with 3H-diisopropylfluorophosphate had a modestly decreased percentage of recovery and circulated with a prolonged half-life. Migration of these cells to skin chambers was approximately equal to that of the subjects' own blood PMNs. Adverse effects included transient bone pain, headache, hunger, and insomnia. CONCLUSIONS: Precollection treatment of leukapheresis donors with G-CSF plus dexamethasone is an effective way to enhance the collection of PMNs with normal or near-normal functional properties for PMN transfusion therapy.

Adult↗
PubMed1989

The monocyte-derived neutrophil activating peptide (NAP/interleukin 8) stimulates human neutrophil arachidonate-5-lipoxygenase, but not the release of cellular arachidonate.

LPS and mitogen-stimulated mononuclear cells secrete a cytokine, which is able to activate the PMNL-arachidonate-5-lipoxygenase. This cytokine has been proven to be identical with the recently characterized novel neutrophil-activating peptide NAP/IL-8. NAP/IL-8 is able to activate human PMNL for release of LTB4, omega-oxidized LTB4, and 5-HETE in the presence of exogenous AA. Half-maximal concentration of NAP/IL-8 for release of LTB4 has been found to be near 4 x 10(-8) mol/liter. Time course studies revealed rapid activation of PMNL, with maximal release of LTB4 within the first 10 min with a decline up to 40 min. High amounts of omega-oxidized LTB4 were detected up to that time. Significant amounts of AA-5-LO-products can be detected only when PMNL were stimulated with NAP/IL-8 in the presence of exogenous AA. The concentration of AA necessary for half-maximal LTB4 release has been found to be 3 x 10(-6) mol/liter. In the presence of 8 x 10(-9) mol/liter [3H]AA, NAP/IL-8 (10(-9) to 10(-7) mol/liter) did not induce the production of LTB4, omega-oxidized LTB4, or 5-HETE. In addition, PMNL prelabeled with [3H]AA did not release either [3H]AA or 5-lipoxygenase metabolites when stimulated with NAP/IL-8 (10(-9) to 10(-7) mol/liter), indicating that NAP/IL-8 apparently does not activate cellular phospholipases/diacylglycerol-lipases. Apart from FMLP, C5a, and PAF NAP/IL-8 is the fourth clearly characterized neutrophil chemotaxin able to activate the PMNL-5-lipoxygenase. The detection of large amounts of NAP/IL-8, arachidonic acid, as well as LTB4-like material, in lesional material of patients with psoriasis points towards a possibly important role of NAP/IL-8 in amplifying inflammatory processes by induction of LTB4-production.

Arachidonate 5-Lipoxygenase↗
PubMed1990

Lipopolysaccharide-stimulated human monocytes secrete, apart from neutrophil-activating peptide 1/interleukin 8, a second neutrophil-activating protein. NH2-terminal amino acid sequence identity with melanoma growth stimulatory activity.

Purification of monocyte-derived NAP-1/IL-8 by preparative reversed-phase (RP)-HPLC led to the detection of a second peak with polymorphonuclear leukocyte (PMNL)-activating (degranulation, chemotaxis) properties. The monokine responsible for this biological activity, which we tentatively termed NAP-3, could be purified to homogeneity by three different RP-HPLC steps. Tricine-SDS-PAGE analysis gave a single line at Mr 5.3 kD (NAP-1/IL-8 = 5.8 kD). NH2-terminal amino acid sequence analysis read as a major sequence (ASVATELRXCXLQT. .), which shows greater than 40% homology to that of NAP-1/IL-8. The sequence is identical to that found for the 13-kD moiety of melanoma growth stimulating activity (MGSA) and the product of the oncogene gro. Determination of neutrophil chemotactic activity of NAP-3 revealed a typical bell-shaped dose-response curve (ED50 = 2 ng/ml) with no significant neutrophil chemotactic activity at doses greater than 200 ng/ml. Also, in cytochalasin B-pretreated PMNL, NAP-3 elicited release of myeloperoxidase and beta-glucuronidase. Crossdesensitization studies in PMNL enzyme release revealed crossreactivities with the NAP-1/IL-8-R on PMNL. NAP-3 (MGSA/gro) appears to represent the first member of the novel supergene family of beta-thromboglobulin-like host defense cytokines, which expresses both mitogenic as well as proinflammatory properties at the nanogram level.

Amino Acid Sequence↗
PubMed1991

Phagocytosing neutrophils produce and release high amounts of the neutrophil-activating peptide 1/interleukin 8.

After phagocytosis of yeast opsonized with IgG, neutrophil leukocytes (polymorphonuclear leukocytes [PMN]) expressed high levels of neutrophil-activating peptide 1/interleukin 8 (NAP-1/IL-8) mRNA, which peaked after 3-5 h and were still elevated after 18 h. A similar but quantitatively less prominent effect was obtained with lipopolysaccharide (LPS). After phagocytosis, but not after exposure to LPS, the PMN progressively released considerable amounts of NAP-1/IL-8 into the culture medium (18.6-50 ng/ml in 18 h). The peptide released was biologically active, as indicated by the transient elevation of cytosolic-free calcium in PMN exposed to aliquots of the culture supernatants, and desensitization by prestimulation of the cells with recombinant NAP-1/IL-8. By producing NAP-1/IL-8 at sites where they phagocytose invading microorganisms, PMN could enhance the recruitment of new defense cells.

Calcium↗
PubMed1995

Childhood onset cyclic neutropenia: G-CSF therapy restores neutrophil count but does not influence superoxide anion and cytokine release by neutrophils.

In this paper we describe the case of a 16-year-old boy with childhood onset cyclic neutropenia (CN) with a 21 d cycle who was successfully treated with recombinant granulocyte-colony stimulating factor (G-CSF). Cyclic therapy with G-CSF (5 micrograms/kg/d s.c. for 1 week every 21 d) maintained peripheral neutrophil count above the normal range, reduced the incidence of severe infections and significantly improved the patient's performance status throughout an 18-month follow-up. Phenotypic analysis of circulating lymphocytes demonstrated that G-CSF treatment does not modify the phenotypic profile of circulating B, T and NK cell populations. Circulating neutrophils released normal amounts of cytokines (including IL-1 beta, IL-8, TNF alpha) and superoxide anion during G-CSF therapy.

Adolescent↗
PubMed1991

Covalent structure of two novel neutrophile leucocyte-derived proteins of porcine and human origin. Neutrophile elastase homologues with strong monocyte and fibroblast chemotactic activities.

The covalent structures of two, novel, neutrophile, leucocyte-derived, strongly basic proteins of porcine and human origin have been determined by microsequencing in combination with time-of-flight plasma desorption mass spectrometry. The porcine protein primary structure of 219 amino acid residues was shown to contain 6 cysteine residues, 2 putative carbohydrate sites and 14% basic residues. The human protein contained 221 amino acid residues of which 8 were cysteine, 4 putative carbohydrate sites and 12% basic. A 47% direct sequence similarity to human neutrophile elastase was found, but due to mutations of two of the three amino acids in the catalytic triad, proteolytic activity is absent. Modelling and alignment studies unveil a close relationship of both proteins to the serine protease family, the greatest similarity being to those serine proteases present in granules from peripheral blood cells. Both proteins have been shown to be chemotactically active for monocytes and fibroblasts in vitro.

Amino Acid Sequence↗
PubMed2006

Neutrophil chemotaxis by pathogen-associated molecular patterns--formylated peptides are crucial but not the sole neutrophil attractants produced by Staphylococcus aureus.

The chemotactic migration of phagocytes to sites of infection, guided by gradients of microbial molecules, plays a key role in the first line of host defence. Bacteria are distinguished from eukaryotes by initiation of protein synthesis with formyl methionine. Synthetic formylated peptides (FPs) have been shown to be chemotactic for phagocytes, leading to the concept of FPs as pathogen-associated molecular patterns (PAMPs). However, it remains unclear whether FPs are major chemoattractants released by bacteria and whether further chemoattractants are produced. A Staphylococcus aureus mutant whose formyltransferase gene was inactivated (Deltafmt) produced no FPs and the in vitro and in vivo ability of Deltafmt culture supernatants to recruit neutrophils was considerably reduced compared with those of the parental strain. However, some chemotactic activity was retained, indicating that bacteria produce also unknown, non-FP chemoattractants. The activity of these novel PAMPs was sensitive to pertussis toxin but insensitive to the formyl peptide receptor inhibitor CHIPS. Deltafmt culture supernatants caused reduced calcium ion fluxes and reduced CD11b upregulation in neutrophils compared with wild-type supernatants. These data demonstrate an important role of FPs in innate immunity against bacterial infections and indicate that host chemotaxis receptors recognize a larger set of bacterial molecules than previously thought.

Animals↗
PubMed2004

Autoantibodies to neutrophil cytoplasmic antigens (ANCA) do not bind to polymorphonuclear neutrophils in blood.

BACKGROUND: Autoantibodies to neutrophil cytoplasmic antigens (ANCA), particularly to proteinase 3 (PR3), are found in the majority of patients with systemic Wegener's granulomatosis. The autoantibodies are widely used as diagnostic markers. Their role in the development and progression of the disease, however, is still under investigation. The primary target of ANCA, PR3, is located in the cytoplasm of polymorphonuclear neutrophils (PMN) or monocytes and is translocated to the cell surface upon stimulation. In patients with Wegener's granulomatosis PR3 is up-regulated most prominently during active disease. Despite the fact that both autoantibodies to PR3 and PMN expressing PR3 are present in patients with Wegener's granulomatosis, there is no evidence for binding of the autoantibodies to PMN. The present study was designed to analyze binding characteristics of autoantibodies to PR3 on PMN. METHODS AND RESULTS: PMN of patients with active Wegener's granulomatosis (N= 10) were tested for autoantibody binding. Despite high autoantibody titer and PR3 expression on the PMN, no surface-bound IgG was found on PMN ex vivo. When ANCA-containing plasma from patients was incubated with isolated PMN, stimulated to express PR3, again no specific binding of the autoantibody could be detected. Also keeping the samples on ice did not allow surface detection of IgG, ruling out degradation or internalization of the autoantibodies. Only when purified IgG fractions were used, binding to PMN was seen in 14 of 25 patients. Already 1% of plasma, however, was sufficient to greatly reduce the IgG binding. Reduced binding of the IgG fraction was also seen when a larger reaction volume was used. CONCLUSION: Our data indicate that autoantibodies to PR3 have a rather low affinity for surface-associated PR3 on PMN. This, in turn, argues against the hypothesis that ANCA contributes to the pathogenesis of the disease by stimulating viable PMN in whole blood.

Antibodies, Anti-Idiotypic↗
PubMed2005

Human anti-neutrophil cytoplasm autoantibodies to proteinase 3 (PR3-ANCA) bind to neutrophils.

BACKGROUND: Recently, the in vivo pathogenic role of anti-neutrophil cytoplasm autoantibodies (ANCA) in ANCA-associated vasculitis has been challenged by Abdel-Salam et al. In their report, they observed that ANCA directed against proteinase 3 (PR3) cannot bind to their target autoantigen PR3 on circulating neutrophils (PMN). Here we present evidence that human PR3-ANCA do specifically bind to PMN that express PR3 on their membrane. METHODS: PMN were isolated from donors showing bimodal membrane PR3 expression on their PMN (N= 3). TNFalpha-primed PMN or PMA-stimulated PMN were incubated with serum or plasma from PR3-ANCA-positive patients with Wegener's granulomatosis (WG) (N= 8) or healthy controls (N= 8). Binding of IgG in serum or plasma samples to PMN was assessed by indirect immunofluorescence. RESULTS: Binding of IgG in undiluted plasma or serum from PR3-ANCA-positive WG-patients to PMN was significantly increased compared to plasma or serum from healthy controls. Dilution of plasma and serum showed concentration-dependent binding of IgG. Double staining for PR3 and IgG demonstrated that IgG in plasma or serum from PR3-ANCA-positive patients only bound to those PMN that expressed PR3, and not to PMN that lacked PR3 expression on their membrane. CONCLUSION: PR3-ANCA in undiluted serum or plasma from PR3-ANCA-positive WG patients bind to TNFalpha- primed and PMA-stimulated PMN that express PR3 on their membrane. Therefore, the hypothesis that PR3-ANCA can bind and activate primed PMN is still the most attractive explanation for the contribution of PR3-ANCA to the pathogenesis of Wegener's granulomatosis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

[Determination of neutrophil function in the respiratory infection by chemiluminescence (CL). I: Change in neutrophil's CL by chemotherapy against the bacterial pneumonia].

We measured neutrophil's CL (CL-index) in 12 patients of the bacterial pneumonia three times per each case: before, during and after chemotherapy. Before the initiation of chemotherapy. CL-index in the six patients remained higher than that in healthy controls, while the remaining six showed lower levels of CL-index compared to the controls. In the 11 cases, their CL-indexes fell to levels lower than those obtained before treatment. Additionally, in the 11 cases their CL-indexes increased after the termination of chemotherapy. Furthermore, in the nine cases the product of the neutrophil number and CL-index was decreased by chemotherapy, and the decrease in the product correlated with improvement in their clinical conditions.

Adolescent↗