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PubMed1991

Effects of protein restriction on functional properties of rat peritoneal macrophages.

Rats were maintained on 20% and 4% protein diets for 3 weeks. The functional properties of thioglycollate (TG) elicited macrophages from these groups were compared with the non elicited resident cells from the protein fed group. Elicitation of macrophages in response to TG was low in the protein deficient group. These cells also exhibited low adherence in overnight cultures compared to those isolated from the protein fed group; however their viability and total protein content remained unaltered. Normal resident and TG elicited cells from 4% protein fed group exhibited an initial lag period in H2O2 production in response to zymosan stimulation. The lag period could be correlated to the high endogeneous catalase activity in these cells. Incubation with zymosan resulted in rapid decline in catalase levels, facilitating evolution of H2O2. On prolonged incubation, the elicited cells from the protein fasted rats evolved about 87% H2O2 compared to the protein fed samples. In the absence of zymosan all the samples possessed comparable NADPH oxidase activity. Zymosan induced activation of this enzyme was higher in TG cells from the protein fed groups, compared to the protein fasted and the resident samples. The cellular enzyme activity, however was not altered in the TG cells of both the groups though it declined rapidly in the corresponding resident cells. Significant reduction (congruent to 50%) in both serum iron and transferrin in the low protein fed samples did not correspondingly affect the oxidative burst process. However the engulfment of yeast cells was greatly impaired due to protein restriction. Adherence and phagocytic properties of macrophages are regulated by the activity of their membrane constituents.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Relationship between phagocyte metabolic function and years of maintenance dialysis.

An index of the activation of NADPH-oxidase in the production of free radicals is CO2 production by the hexose monophosphate shunt of polymorphonuclear cells (PMN). 14CO2 production from glucose-1-C14 was studied as an indicator of PMN function after addition of latex or zymosan to predialysis whole blood, and correlated with the years spent on hemodialysis. In a series of 49 patients, a nadir in PMN metabolic activity, when compared with healthy controls, was reached in a subgroup treated for less than 24 months (n = 24, latex: 109.5 +/- 10.1 vs. 233.7 +/- 11.8; zymosan: 181.9 +/- 18.9 vs. 407.8 +/- 19.3 DPM/10(3) PMNs; p less than 0.01). In patients treated by dialysis for longer than 24 months, PMN metabolic function was significantly better, resulting in partial correction of the defect for both latex and zymosan. Phagocyte CO2 production in response to latex or zymosan correlated significantly with years of dialysis treatment (r = 0.63 and 0.56, respectively, n = 49; p less than 0.001). These findings may have implications for phagocyte reactivity towards infection, bioincompatible dialyzer membranes, and renal transplantation.

Energy Metabolism↗
PubMedDate not supplied

[Induction of granulomatous liver inflammation by noninfectious particles].

A single intravenous injection of 0.1 mg/g of zymosan led to the formation of granuloma-type clusters of mononuclears in the liver of CBA mice or (CBA X C57B1)F1 hybrid mice. The area occupied by the granulomas grows for 3 to 9 days and then gradually diminishes so that the granulomas disappear practically in one month. Hydrocortisone injected in a dose of 125 mg/kg 2 and 24 hours before or 2 and 24 hours after zymosan inhibited the initiation of granulomas but, at the same time, led to their slower involution. Mice with zymosan-induced granulomas became hypersensitive to the derivate of an endotoxin--prodigiosin, a polysaccharide obtained from S. marcescens. After intravenous infusion of a preparation of corpuscular alkaline phosphatase (CAP) granuloma-like structures also appear in the liver of rats. In distinction from zymosan-induced granulomas they persist for a much longer time (up to 27 weeks). The first signs of CAP-induced granulomas appear in 3 days. The liver per cent by volume occupied by the granulomas gradually doubles by the 15th week and then reduces. At the same time, the number of granulomas per 1 mm3 of hepatic tissue remains practically constant for 3 to 21 weeks from the moment of the induction by CAP. Their average size grows slowly and reaches maximum by the 15th week, with significant variations. Desmine and reticular fibres accumulate in the granulomas, which is evidence of active involvement of hepatic fat-accumulating cells in their formation. The results show that resident macrophages are the triggers of granulomatous inflammation of the liver.

Animals↗
PubMed1989

Effects of glycolytic and cytoskeletal inhibitors on phagocytic and nitroblue tetrazolium reductive activities of bovine neutrophils.

Phagocytic and oxidative metabolic activities of bovine blood neutrophils were determined in the presence of glycolytic (NaF) and cytoskeletal (colchicine, cytochalasin B, and prostaglandin E1) inhibitors. Phagocytosis and post-phagocytic oxidative metabolic activity, measured by nitroblue tetrazolium reduction, were determined using zymosan, Escherichia coli, Staphylococcus aureus, or Streptococcus agalactiae. Sodium fluoride (1.25 microM to 1.25 mM concentrations) did not significantly (P greater than 0.05) inhibit phagocytosis of S aureus and Str agalactiae, whereas phagocytosis of zymosan and E coli was significantly (P less than 0.05) inhibited only at 1.25 mM concentration. Colchicine at 1.25 nM to 1.25 microM concentrations significantly inhibited phagocytosis of zymosan and E coli, but not of S aureus and Str agalactiae. Cytochalasin B at 1.25 nM to 1.25 microM concentrations significantly inhibited phagocytosis of zymosan and all 3 bacteria, whereas prostaglandin E1 was noninhibitory at similar concentrations. Nitroblue tetrazolium reduction, in general, was not significantly affected by NaF and cytoskeletal inhibitors.

Alprostadil↗
PubMed1987

Inhibition of monocyte oxidative responses by Bordetella pertussis adenylate cyclase toxin.

Bordetella pertussis and the other Bordetella species produce a novel adenylate cyclase toxin which enters target cells to catalyze the production of supraphysiologic levels of intracellular cyclic adenosine monophosphate (cAMP). In these studies, dialyzed extracts from B. pertussis containing the adenylate cyclase toxin, a partially purified preparation of adenylate cyclase toxin, and extracts from transposon Tn5 mutants of B. pertussis lacking the adenylate cyclase toxin, were used to assess the effects of adenylate cyclase toxin on human peripheral blood monocyte activities. Luminol-enhanced chemiluminescence of monocytes stimulated with opsonized zymosan was inhibited greater than 96% by exposure to adenylate cyclase toxin-containing extract, but not by extracts from adenylate cyclase toxin-deficient mutants. The chemiluminescence responses to particulate (opsonized zymosan, Leishmania donovani, and Staphylococcus aureus) and soluble (phorbol myristate acetate) stimuli were inhibited equivalently. The superoxide anion generation elicited by opsonized zymosan was inhibited 92% whereas that produced by phorbol myristate acetate was inhibited only 32% by B. pertussis extract. Inhibition of oxidative activity was associated with a greater than 500-fold increase in monocyte cAMP levels, but treated monocytes remained viable as assessed by their ability to exclude trypan blue and continued to ingest particulate stimuli. The major role of the adenylate cyclase toxin in the inhibition of monocyte oxidative responses was demonstrated by: 1) little or no inhibition by extracts from B. pertussis mutants lacking adenylate cyclase toxin; 2) high level inhibition with extract from B. parapertussis, a related species lacking pertussis toxin; and 3) a reciprocal relationship between monocyte cAMP levels and inhibition of opsonized zymosan-induced chemiluminescence using both crude extract and partially purified adenylate cyclase toxin. Pertussis toxin, which has been shown to inhibit phagocyte responses to some stimuli by a cAMP-independent mechanism, had only a small (less than 20%) inhibitory effect when added at concentrations up to 100-fold in excess of those present in B. pertussis extract. These data provide strong support for the hypothesis that B. pertussis adenylate cyclase toxin can increase cAMP levels in monocytes without compromising target cell viability or impairing ingestion of particles and that the resultant accumulated cAMP is responsible for the inhibition of oxidative responses to a variety of stimuli.

Adenylate Cyclase Toxin↗
PubMed1985

[Immunomodulating and antitumor activity of polysaccharides of plant origin].

The effect of the polysaccharides tagetan, palustran, and zymosan injections to BALB/c mice on the formation of cytotoxic T-lymphocytes in allogenic mixed culture has been studied. Lymphocytes from a 5-day-old mixed culture were characterized by the greatest cytotoxic activity, with spleenocytes serving as reacting cells in mice injected 12-50 mg/kg of tagetan, 20 mg/kg of zymosan and 10-100 mg/kg of palustran, 7, 3 and 5 days, respectively, before the beginning of allogeneic stimulation in vitro. To determine correlation between immunostimulating and antitumor activity 25 mg/kg of tagetan every 14 days, 20 mg/kg of zymosan every 6 days, and 10 mg/kg of palustran every 6 days, were injected to BALB/c and BALB/c nu/nu mice prior to and following subcutaneous implantation of Crocker sarcoma cells. By the end of the first month of immunotherapy the tumour size in mice on tagetan or zymosan was 2-2,5 times smaller than in control animals. Tumour growth inhibition with palustran was about 30%. Polysaccharide administration to BALB/c nu/nu mice was not accompanied by tumour growth inhibition. The data obtained suggest that inhibition of Crocker sarcoma growth in mice injected the above polysaccharides is mediated by stimulation of antitumour T-cell activity.

Adjuvants, Immunologic↗
PubMed1986

Do human neutrophils make hydroxyl radical? Determination of free radicals generated by human neutrophils activated with a soluble or particulate stimulus using electron paramagnetic resonance spectrometry.

Using electron paramagnetic resonance spectrometry and the spin trap 5,5-dimethyl-1-oxide (DMPO), neutrophil free radical production in response to phorbol myristate acetate and opsonized zymosan was investigated. Using phorbol myristate acetate and zymosan (3 mg/ml), the superoxide spin-trapped adduct 2-2-dimethyl-5-hydroperoxy-1-pyrrolidinyloxyl (DMPO-OOH) and the hydroxyl spin-trapped adduct 2-2-dimethyl-5-hydroxy-1-pyrrolidinyloxyl (DMPO-OH) were detected. Only DMPO-OH was observed with zymosan (0.5 mg/ml). Hydroxyl radical production in the presence of dimethylsulfoxide (Me2SO) and DMPO yields 2,2,5-trimethyl-1-pyrrolidinyloxyl. The only 2,2-trimethyl-1-pyrrolidinyloxyl detected following neutrophil stimulation was that expected from DMPO-OOH degradation. Superoxide dismutase but not catalase inhibited generation of all three spin-trapped adducts. These data indicate that DMPO-OH arose from DMPO-OOH degradation and does not represent hydroxyl radical production. Under certain conditions DMPO-OH is the predominant spin-trapped adduct resulting from neutrophil superoxide production, perhaps due to cellular bioreduction of DMPO-OOH to DMPO-OH. Cytochalasin B, which prevents phagosome closure, inhibited zymosan-stimulated neutrophil oxygen consumption and electron paramagnetic resonance superoxide detection. No hydroxyl radical was detected. Spin trapping with DMPO appears to detect intraphagosomal free-radical formation.

Cell Separation↗
PubMed1988

Similarities in function between pancreatic tumor cells and macrophages and their inhibition by murine monoclonal antibodies.

Fine structural studies of human pancreatic adenocarcinomas have demonstrated their composition of one major secretory cell type, a mucin secreting cell. It was also demonstrated that pancreatic tumor cells have a high endocytotic activity via the regular endocytotic pathway with uptake via coated pits and vesicles. These findings indicate a striking similarity between pancreatic tumor cells and human mononuclear phagocytes. Therefore monocyte-related functions like endocytosis, lysosomal enzyme secretion and superoxide anion production were measured in various cell lines of human pancreatic adenocarcinomas in comparison to human mononuclear phagocytes. These functions were measured under basal conditions and after exposure to zymosan or immune complexes. All pancreatic tumor cells tested demonstrated increased endocytotic, secretory and oxidative burst activity to a similar extent as human mononuclear phagocytes after exposure to the stimuli (zymosan or immune complexes). In a further attempt murine monoclonal antibodies produced against pancreatic tumor cells were characterized in relation to their tissue specificity, the epitope recognized in in vitro and in vivo radiolocalization and their potential to mediate biological functions (e.g. antibody dependent cellular cytotoxicity or complement mediated cytolysis). Mouse monoclonal IgG1 antibodies which specifically bind to the majority of well differentiated adenocarcinomas of the human pancreas as well as to human mononuclear phagocytes have been shown to inhibit several cellular functions (lysosomal enzyme release, pinocytosis of colloidal gold 198Au, and chemiluminescence) of those cells. Incubation of 10 micrograms/ml of monoclonal IgG1 antibody with pancreatic tumor cell lines or human monocytes either simultaneous or followed by the stimulation with zymosan (50 micrograms/ml) or immune complexes (100 micrograms/ml) resulted in the inhibition of lysosomal enzyme release and uptake of colloidal radioactive gold of both human mononuclear phagocytes and pancreatic tumor cells responding to zymosan or immune complexes. In addition those monoclonal antibodies have been found to inhibit luminol-dependent chemiluminescence. Kinetic measurements of chemiluminescence showed a quick inhibition of this activity on both cell types within 1 to 3 minutes. Antibody F(ab')2 fragments behaved analogously to the whole antibodies, whereas monovalent Fab fragments were not able to inhibit any of the mentioned functions. When used alone the monoclonal antibodies were not cytotoxic and did not theirselves trigger release of acid hydrolases, did not alter pinocytosis and did not induce oxidative metabolism.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMed1983

Isolation and identification of the third component of complement of Japanese quails.

The identification of the third component of complement (C3) of Japanese quails was attempted by using rabbit antiserum prepared against quail serum-treated zymosan (ZX) as an initial reagent. This antiserum (anti-ZX) had agglutinating activity on rabbit erythrocytes reacted with quail antibody and quail complement (EACq) but not on EAq, and developed two precipitin lines against quail serum at beta- and gamma-regions in crossed immunoelectrophoresis. Subsequently, monospecific antisera to each of these precipitin lines were prepared in rabbits, and quail serum proteins reactive with these antisera were purified by salt precipitation followed by Sephadex gel filtration and DEAE cellulose column chromatography. One protein with a m.w. of 184,000 (184K) resembled mammalian C3 in that: 1) monospecific antiserum (anti-184K protein serum) agglutinated EACq but not EAq; 2) treatment of fresh quail serum with either inulin or zymosan resulted in the conversion of the precipitin line developed against 184K protein from gamma to beta in crossed immunoelectrophoresis; 3) the 184K protein was shown to consist of two polypeptide chains of 110K and 73K linked by disulfide bonds. Furthermore, the 184K protein in serum was cleaved through the incubation with inulin to 174K and 140K proteins that might correspond to C3b and C3c of human complement; 4) the 184K protein bound to zymosan was eluted with hydrazine or methylamine but not with Nonidet P-40, indicating that 184K protein binds to zymosan by a covalent bond but not by a hydrophobic one; and 5) by treatment of fresh quail serum with methylamine, complement reactivity was reduced, although its activity was restored by the addition of purified 184K protein. These results suggest the 184K protein is the quail's equivalent to mammalian C3. When quail serum was reacted with cells that had complement-activating capacity, quail C3 deposited on their membrane as in mammalians; however, no conversion of quail C3 was noted by the reaction with CVF. Antibody to quail C3 failed to cross-react with that in mammals.

Animals↗
PubMed1981

Control of arachidonic acid accumulation in bone marrow-derived macrophages by acyltransferases.

The turnover of phospholipid fatty acid moieties of bone marrow-derived macrophages was analyzed by separate determination of degrading and acylating activities. Acylating activities were followed in intact cells by incubation with excess arachidonic acid and degradation of phospholipids was followed in cells prelabeled with fatty acids. Significant phospholipase A2 activity was detectable only if the reutilization of liberated fatty acid was inhibited , e.g. by p-chloromercuribenzoate. It was of interest that the divalent cation ionophore A 23187 and various antiphlogistic drugs like indomethacin, diclofenac, and acetylsalicylic acid were found to inhibit the acylation reaction. These compounds led to increased levels of free arachidonic acid in stimulated, as well as in unstimulated cells. Increased activities of phospholipase A2 were achieved by treatment with the bivalent cation ionophore A 23187 and with zymosan. The effect of zymosan obtained from various sources was found to be exclusively due to contamination of tee zymosan particles with phospholipase A2 activity. Even when the cellular phospholipase activity was increased by the addition of exogenous phospholipase activity contained in the zymosan particles, degradation of cellular phospholipids was not measurable unless the reacylation was inhibited. These results suggest that in the cells studied, the level of free arachidonic acid is mainly controlled by the activity of the lysophosphatide acyltransferase.

Acyltransferases↗
PubMed1995

[The effect of ranitidine on postoperative monocyte and neutrophil granulocyte function].

The histamine H-2-receptor antagonist ranitidine hydrochloride has been shown to alleviate trauma-, blood transfusion- and sepsis-induced immunosuppression. We evaluated the effect of ranitidine on the postoperative impairment of monocyte and neutrophil function in 24 patients undergoing major elective abdominal surgery. The patients were randomized to receive postoperative adjuvant treatment with ranitidine hydrochloride (100 mg) administered intravenously twice daily for four days, followed by oral ranitidine hydrochloride (150 mg) administered twice daily for five days (n = 11), or no adjuvant treatment (n = 13). Blood monocyte and neutrophil chemotaxis and chemiluminescence were analyzed before the operation and on post-operative days one, three and nine. Monocyte chemotaxis to C5a in the 13 control patients was significantly decreased on day one compared to day 0. Chemotaxis in the 11 ranitidine-treated patients increased significantly from day 0 to day one (p < .01 between groups). Neutrophil chemiluminescence to zymosan and N-f-methionyl-leucylphenylalanine was significantly increased in control patients on day one compared to day 0 (p < .05), while ranitidine reduced chemiluminescence to zymosan insignificantly on day one (p < .07 between groups). Five of the 13 control patients developed postoperative infectious complications, which were related to decreased monocyte chemotaxis to C5a and increased neutrophil chemiluminescence to zymosan when compared to noninfected patients. A significant difference (P < .05) in chemiluminescence to zymosan between infected and noninfected control patients was observed on day three, before clinical signs of infectious disease could be detected. There were no infectious complications in ranitidine-treated patients. These results support previous studies on the effect of ranitidine in reducing postoperative immunosuppression.

Administration, Oral↗
PubMed1994

Stimulatory and inhibitory action of nitric oxide donor agents vs. nitrovasodilators on reactive oxygen production by isolated polymorphonuclear leukocytes.

Nitrovasodilators, particularly the nitric oxide donor agents, are known to inhibit leukocyte functions such as chemotaxis, adherence, migration and proteolytic enzyme release. In this study, we investigated the modulatory role of nitric oxide donor agents on reactive oxygen production by canine polymorphonuclear leukocytes using luminol-enhanced chemiluminescence (LDCL). LDCL was measured before and after activation using 1 mg/ml of opsonized zymosan in the absence or presence of various agents. Unlike the nitrovasodilators, nitroglycerin and nicorandil, the nitric oxide donor agents, 3-morpholinosydnonimine (SIN-1) and sodium nitroprusside, both produced enhanced stimulation of LDCL following zymosan at low concentrations of the agonist and inhibition at high concentrations of the agonist. SIN-1 and sodium nitroprusside (but not nitroglycerin or nicorandil) also produced LDCL before activation of cells with zymosan. This increase was blocked by superoxide dismutase or catalase but not by the hydroxyl radical scavenger, mannitol. SIN-1c, the inactive product of SIN-1 produced no LDCL. Furthermore, incubation of 10 microM SIN-1 or nitroprusside with luminol in the absence of cells produced no chemiluminescence at these drug concentrations. The stimulation of LDCL in the prezymosan phase was partially inhibited by methylene blue and L-nitroarginine methyl ester. In zymosan-stimulated cells, the enhanced LDCL induced by SIN-1 was prevented with superoxide dismutase, catalase (but not mannitol) and reversed with L-nitroarginine methyl ester. Thus, nitric oxide donor agents may either stimulate or inhibit oxygen radical production by isolated neutrophils depending on the drug concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Multiple organ dysfunction syndrome: end organ and systemic inflammatory response in a mouse model of nonseptic origin.

The authors measured the peripheral blood pro-inflammatory cytokine responses (tumor necrosis factor-alpha [TNF-alpha] and interleukin-6 [IL-6]) and related end organ responses ti intraperitoneal zymosan-saline suspension over 5 days in CD-1 mice. Other indicators of local and systemic inflammation included wet:dry weight ratios of lung, liver, kidneys, spleen, and bowel; peripheral blood hematocrit, white blood cell count, and platelet count; lung myeloperoxidase activity; lung protein leak; and bacterial translocation to liver, spleen, and mesenteric lymph nodes. The initial event in responses to zymosan A injection was a sharp rise in the peripheral blood TNF-alpha level, which crested within 1 h of injection. This response was followed by a peripheral blood leukocytosis also within 1 h, and a peak lung myeloperoxidase activity within 1-2 h of injection. The maximum lung permeability index occurred 8 h after injection (zymosan, .398 +/- .019 [n = 10]; saline vehicle, .266 +/- .007 [n = 10], p < .001) followed by the maximum lung wet:dry weight ratio, which occurred 18 h after injection. The peak wet:dry weight ratios for the other organs occurred between 12 and 24 h after injection as well. Peripheral blood IL-6 maxima followed TNF-a maxima after lags of several hours. The release of pre-formed TNF-a is likely the most proximal event following injection of zymosan, and may set in motion the processes that result in end-organ injury and secondary multiple organ dysfunction, particularly activation of leukocytes. The precise roles of TNF-alpha and IL-6 in the pathogenesis of end-organ injury, however, are not addressed.

Animals↗
PubMed1991

Studies of the route, magnitude, and time course of bacterial translocation in a model of systemic inflammation.

Bacteria have been documented to translocate from the gut to systemic organs, yet the exact route by which they translocate remains unclear. To determine the route of bacterial translocation, different dosages of zymosan were used to activate complement and cause systemic inflammation. At a zymosan dose of 0.1 mg/g, bacteria translocated only to the mesenteric lymph node complex, whereas at a dose of 0.5 mg/g the bacteria translocated systematically. In rats receiving 0.5-mg/g doses of zymosan, the bacteria appeared to reach systemic organs via the portal blood rather than via the mesenteric lymph, as bacteria were present in 87% of portal blood samples but only 25% of lymph samples. The number of bacteria exiting the portal vein was 11,500 times greater than the number exiting via the lymph. Thus, both the route and extent of bacterial translocation varies based on the magnitude of the inflammatory insult, with the portal blood being the major route of bacterial translocation to systemic organs.

Animals↗
PubMedDate not supplied

Lucigenin- and luminol-enhanced chemiluminescence in turkey monocytes.

Monocytes from 10 week-old specific pathogen-free turkeys were isolated from peripheral blood by density centrifugation and assayed for their oxidative activity by means of a luminometer. Chemiluminescence (CL) properties after stimulation with different soluble and particulate stimuli were compared in lucigenin- and luminol-enhanced assays. A distinct response could be measured with 12-phorbol 13-myristate acetate (PMA) and Zymosan A, but only a weak signal was obtained with calcium ionophore A23187. No oxidative activity could be induced with N-formyl-methionyl-phenylalanine. Peak maxima for both lucigenin- and luminol-enhanced CL were ranked: PMA > Zymosan A > calcium ionophore. The velocity of the lucigenin- and luminol-enhanced responses induced by calcium ionophore were of similar magnitude, but the lucigenin-enhanced responses of Zymosan A and PMA-stimulated monocytes were respectively about 5 and 10 times higher than those obtained in luminol-enhanced assays. No peroxidase activity could be detected in the purified turkey monocytes. As luminol-enhanced CL primarily results from the peroxidase activity, this lack of myeloperoxidase may explain the observed lower responses to the different stimuli, in the presence of a luminol. In contrast, lucigenin-enhanced CL is not related to peroxidase activity, but is a selective probe of oxidase activity. Irrespective of the myeloperoxidase deficiency, different soluble and particulate stimuli induced a significant and reproducible CL response in turkey monocytes, in the presence of both chemiluminigenic probes, lucigenin and luminol. The possibility of measuring the phagocyte oxygenation activity of turkey monocytes represents a useful tool for the study of monocyte mediated host defence in the turkey.

Acridines↗
PubMedDate not supplied

Different effects of exogenous horseradish peroxidase on luminol-amplified chemiluminescence induced by soluble and particulate stimuli in human neutrophils.

The chemiluminescence (CL) technique with scavengers for superoxide anion (superoxide dismutase) and hydrogen peroxide (catalase) was used to characterize the generation of reactive oxygen species (ROS) inside and outside the human neutrophil after stimulation with both soluble (formyl-methionyl-leucyl-phenylalanine, FMLP) and particulate (urate crystals, zymosan, oxidized LDL) stimuli. Depending on the stimulus used, ROS generation differed in composition and absolute amounts. The ratio between extracellularly and intracellularly produced ROS ranged from 0.3 (zymosan) to 4.2 (FMLP). While enhancing substantially FMLP-stimulated CL, horseradish peroxidase inhibited CL induced by particulate stimuli by 40-80%. Furthermore, an azide-insensitive and therefore peroxidase-independent part of CL was found in FMLP-, LDL- and zymosan-stimulated cells. The results indicate that different agonists may lead through distinct chemical pathways to neutrophil luminol-amplified light generation.

Autoanalysis↗
PubMed1980

Surface immunoglobulin, lectin-induced cap formation, and phagocytic function in five patients with the leukemic phase of hairy cell leukemia.

Hairy cells from 5 patients with greater than 25% hairy cells in the peripheral blood (4 had greater than 45% hairy cells and white blood cell counts (WBC) greater than 10,000/mm3) were studied for surface immunoglobulin (SIg) presence and distribution by two methods, for lectin-induced cap formation, and for phagocytosis of zymosan. Hairy cells from all 5 cases were found to have distinct monoclonal patterns, 2 Gk, 1 MDk, 1 Dk, and 1 GMDk, as well as cap formation with SIg. All 5 cases showed distinct lectin-induced cap formation in a percentage of cells similar to the percentage of hairy cells, and 2 of the 5 patients had hairy cells which phagocytosed zymosan. These findings contrasted with the malignant cells from 4 patients with CLL, which had monoclonal SIg but no SIg cap formation and no significant percentage of lectin-induced cap formation. Cells from 2 cases of T cell lymphomas had no SIg and no lectin-induced cap formation as did cells from 2 cases of non-lymphocytic leukemia. Hairy cells not only appear to have SIg cap formation similar to some B-lymphocytes, which in some patients also phagocytose zymosan, but also demonstrate strong lectin-induced cap formation.

Adult↗
PubMed1981

Opsonic activity of myeloma immunoglobulins (MM-Ig).

Patients with MM are at an increased risk for life-threatening bacterial infections, primarily by organisms that require opsonization for interaction with granulocytes. In the present study we used a neutrophil chemiluminescence (CL) assay of opsonization to explore the opsonic activity of MM-Ig for zymosan particles. Particles were treated with serum lacking in Ig to explore the contribution of Ig to zymosan opsonization. This serum was found to have 69 +/- 2.6% (X +/- SEM) of the opsonic activity of normal serum (P less than .001). Normal serum concentrations of normal IgG, MM-IgG, and MM-IgA all lacked opsonic activity for zymosan. However, when particles were treated with Nl-IgG, MM-IgG, or MM-IgA as well as complement, normal opsonic activity was generated. Increasing the concentration of the Ig to stimulate MM serum did not inhibit this opsonic activity. Thus both MM-IgG and MM-IgA can function as normal, nonspecific opsonins.

Granulocytes↗