Generation of superoxide by immunologically stimulated normal human neutrophils and possible modulation by intracellular and extracellular SOD and rheumatoid factors

Increased β-glucuronidase activity in bronchoalveolar lavage fluid of children with bacterial lung infection: A case-control study

BACKGROUND AND OBJECTIVE

β-Glucuronidase is a lysosomal enzyme released into the extracellular fluid during inflammation. Increased β-glucuronidase activity in the cerebrospinal and peritoneal fluid has been shown to be a useful marker of bacterial inflammation. We explored the role of β-glucuronidase in the detection of bacterial infection in bronchoalveolar lavage fluid (BALF) of paediatric patients.

METHODS

In this case-control study, % polymorphonuclear cell count (PMN%), β-glucuronidase activity, interleukin-8 (IL-8), tumour necrosis factor-α (TNF-α) and elastase were measured in culture-positive (≥10(4) cfu/mL, C+) and -negative (C-) BALF samples obtained from children.

RESULTS

A total of 92 BALF samples were analysed. The median β-glucuronidase activity (measured in nanomoles of 4-methylumbelliferone (4-MU)/mL BALF/h) was 246.4 in C+ (interquartile range: 71.2-751) and 21.9 in C- (4.0-40.8) (P < 0.001). The levels of TNF-α and IL-8 were increased in C+ as compared with C- (5.4 (1.7-12.6) vs 0.7 (0.2-6.2) pg/mL, P < 0.001 and 288 (76-4300) vs 287 (89-1566) pg/mL, P = 0.042, respectively). Elastase level and PMN% did not differ significantly (50 (21-149) vs 26 (15-59) ng/mL, P = 0.051 and 20 (9-40) vs 18 (9-34) %, P = 0.674, respectively). The area under the curve of β-glucuronidase activity (0.856, 95% confidence interval (CI): 0.767-0.920) was higher than that of TNF-α (0.718; 95% CI: 0.614-0.806; P = 0.040), IL-8 (0.623; 95% CI: 0.516-0.722; P = 0.001), elastase (0.645; 95% CI: 0.514-0.761; P = 0.008) and PMN% (0.526; 95 % CI: 0.418-0.632; P < 0.001).

CONCLUSIONS

This study demonstrates a significant increase of β-glucuronidase activity in BALF of children with culture-positive bacterial inflammation. In our population β-glucuronidase activity showed superior predictive ability for bacterial lung infection than other markers of inflammation.

Correlation of cerebrospinal fluid beta-glucuronidase activity with plasma methotrexate concentrations in leukemic children receiving high-dose methotrexate

BACKGROUND

The activity of lysosomal enzymes is increased in body fluids during inflammation, in which cellular malfunction and cellular death occurs. Because chemotherapy also causes cell malfunction and death, for identifying a neurologic effect, we studied the activity of beta-glucuronidase in the cerebrospinal fluid (CSF) of leukemic children during treatment.

PROCEDURE

The beta-glucuronidase activity in CSF was determined in 13 patients with B-precursor acute lymphoblastic leukemia (ALL) treated with the medium risk arm of ALL Berlin-Frankfurt-Munster (BFM) 95 protocol. Plasma methotrexate (MTX) levels were determined at 24 and 48 hr after the infusion of high-dose (5 g/m(2)/24 hr) MTX (MCA phase).

RESULTS

The mean (SD) beta-glucuronidase activity prior to the onset of chemotherapy was 19.9 (5.6) nmoles/4-methylumbelliferone/ml/hr. No significant changes in activity were noted during the phases of the protocol except of the MCA3. The activity was 24.4 (6.8) on MCA2, 28.4 (9.3) on MCA3, and 24.1 (9.5) on MCA4. The beta-glucuronidase activity was positively correlated with the plasma MTX levels at both 24 hr (r = 0.483, P = 0.006) and 48 hr (r = 0.676, P < 0.0001). No progressive changes were noted during the different phases of the protocol. The greatest beta-glucuronidase activity was measured in two patients with neurotoxicity.

CONCLUSIONS

The beta-glucuronidase activity is increased in the CSF of leukemic children receiving high-dose MTX and particularly in neurotoxicity. It is positively correlated with plasma MTX levels. No cumulative effect of the chemotherapy was observed. The increased beta-glucuronidase activity is most likely due to enzyme leakage through the cell membranes caused mainly by a toxic effect of MTX on the cells of the central nervous system (CNS).

Extracellular superoxide dismutase in biology and medicine

Accumulated evidence has shown that reactive oxygen species (ROS) are important mediators of cell signaling events such as inflammatory reactions (superoxide) and the maintenance of vascular tone (nitric oxide). However, overproduction of ROS such as superoxide has been associated with the pathogenesis of a variety of diseases including cardiovascular diseases, neurological disorders, and pulmonary diseases. Antioxidant enzymes are, in part, responsible for maintaining low levels of these oxygen metabolites in tissues and may play key roles in controlling or preventing these conditions. One key antioxidant enzyme implicated in the regulation of ROS-mediated tissue damage is extracellular superoxide dismutase (EC-SOD). EC-SOD is found in the extracellular matrix of tissues and is ideally situated to prevent cell and tissue damage initiated by extracellularly produced ROS. In addition, EC-SOD is likely to play an important role in mediating nitric oxide-induced signaling events, since the reaction of superoxide and nitric oxide can interfere with nitric oxide signaling. This review will discuss the regulation of EC-SOD and its role in a variety of oxidant-mediated diseases.

Increased activity of lysosomal enzymes in the peritoneal fluid of bacterial peritonitis

OBJECTIVE

The activity of lysosomal enzymes is increased in the cerebrospinal fluid of bacterial meningitis, suggesting that inflammation may cause leakage of lysosomal enzymes into the extracellular fluid. Our objective was to study the activity of 3 lysosomal enzymes in cell-free peritoneal fluid of patients with peritoneal inflammation.

METHODS

The beta-galactosidase, beta-glucuronidase, and alpha-mannosidase activity (nmol 4-methylumbelliferone/mL/h); the total, polymorphonuclear, and mononuclear cell number; and chemical parameters were determined in the peritoneal fluid of 26 patients with culture-positive acute bacterial peritonitis, 13 patients (under antibiotic treatment) with culture-negative bacterial peritonitis, 6 patients with acute mesenteric lymphadenitis, and 26 control subjects who were operated on for surgical conditions without peritoneal inflammation.

RESULTS

The median beta-galactosidase activity in the culture-positive bacterial peritonitis, mesenteric lymphadenitis, and controls was 175 (range: 63--2210), 50 (range: 37--56), and 16 (range: 8--32), respectively. The beta-glucuronidase was 488 (range: 79--998), 53 (range: 27--98), and 15 (range: 3--22), respectively. The alpha-mannosidase was 801 (range: 100-3172), 78 (range: 33--157), and 41 (range: 16--63), respectively. The differences of the enzyme activities among the groups of the subjects studied were significant, with the exception of the alpha-mannosidase activity between mesenteric lymphadenitis and controls. There was no significant correlation between the enzyme activities and the cytologic or chemical parameters studied.

CONCLUSIONS

The elevation of the lysosomal enzymes' activity in the peritoneal fluid of patients with bacterial peritonitis seems to be a reliable index of peritoneal infection. Of the enzymes studied, the beta-glucuronidase and beta-galactosidase activities provide the best means for diagnosing bacterial inflammation of the peritoneal cavity.

Increased activity of lysosomal acid hydrolases in the cell-free cerebrospinal fluid of bacterial meningitis

Because inflammation could affect lysosomal enzyme trafficking, resulting in increased enzyme release from the cells, tissue necrosis, or altered blood- and the brain-cerebrospinal fluid (CSF) barrier, the activity of four lysosomal enzymes in the cell-free CSF of 34 patients with bacterial meningitis, 20 with aseptic meningitis, and 39 control subjects was measured. Activities are expressed in nanomoles of 4-methylumbelliferone mL/h. The median beta-hexosaminidase A activity in bacterial meningitis was 313, in aseptic meningitis it was 173, and in the control subjects it was 175, the median beta-hexosaminidase B activity was 417, 165, and 120; the median alpha-mannosidase activity was 171, 124, and 113; and the median beta-glucuronidase activity was 133.7, 14.3, and 10.0, respectively. The difference of the activities of the four enzymes measured between the bacteria meningitis and the controls is significant (p < 0.000). Also significant is the difference between bacterial and aseptic meningitis (p = 0.005 to < 0.000), but it is not significant between aseptic and control subjects. Both the sensitivity and specificity of the beta-glucuronidase activity between bacterial meningitis and control subjects were 100%, whereas the corresponding values between bacterial and aseptic meningitis were 100% and 90%, respectively. No significant correlation was observed between the activities of the enzymes measured and the number of the polymorphonuclear leukocytes or other laboratory characteristics of the CSF. The increased lysosomal enzyme activities in the CSF of patients with meningitis may result from diffusion across the blood-CSF or the brain-CSF barrier or from enzyme leakage through the cell membranes.

The mechanism for the effect of selenium supplementation on immunity

Lipid peroxide (LPO) in lymphocytes from mice was evaluated by measuring substances reactive to thiobarbituric acid (TBA). The product resulting from the reaction of TBA with lymphocytes was extracted with n-butyl and fluorescence intensity was determined. The degree of lipid peroxidation, expressed as fluorescence intensity f547, was assessed for stimulation of lymphocytes with concanavalin A (Con A), and was related to lymphocyte proliferation in response to Con A if Se was administered. The lymphocyte proliferation was determined by [3H]thymidine incorporation, expressed as cpm. The effect of superoxide dismutase (SOD), added to cell culture on lymphocyte proliferation was also evaluated. It was found that LPO in lymphocytes before Con A stimulation was significantly less than that after stimulation (p < 0.001), and that SOD promoted lymphocyte proliferation dose dependently. The addition of Na2Seo3 to lymphocyte culture or supplementation in drinking water to mice decreased the produced LPO in lymphocyte in response to Con A. In the presence of Se, there is an inverse correlation between the levels of LPO in lymphocyte and the stimulated proliferation (r = -0.8902, r = -0.9439). In conclusion, active oxygen species scavenging was proposed as one of the mechanisms for Se to promote immunity.

Anti-inflammatory effects of recombinant human manganese superoxide dismutase on adjuvant arthritis in rats

The anti-inflammatory effects of recombinant human manganese superoxide dismutase on adjuvant arthritis was investigated. Local application of this manganese superoxide dismutase given every 2 days not only significantly reduced foot swelling but also retarded radiological bone destruction in adjuvant arthritis. Copper zinc superoxide dismutase had little effect on foot swelling.

The respiratory burst of neutrophils, a prognostic parameter in head and neck cancer?

Flow cytometric measurements of the respiratory burst of granulocytes (PMN) from 27 patients with advanced carcinomas of the head and neck revealed two types of responses to a stimulus with phorbol myristate acetate (PMA) before, during, and after radiochemotherapy. (1) The majority (74%) of patients responded quantitatively normal (31-fold increase of fluorescence intensity after PMA stimulation, as in controls) but exhibited functional subpopulations in 63% of samples with varying degrees of hyperreactive PMN. (2) A subgroup of 7 patients did not respond to PMA before and during treatment ("nonresponders"), but in two cases responded after therapy. Survival analysis revealed a significantly (P less than 0.02) decreased mean survival time of nonresponders (36 weeks vs greater than 70 weeks in "responders"). Thus, the respiratory burst of PMN could serve as a prognostic parameter in head and neck cancer.

Chemotactic activities of peripheral blood polymorphonuclear leukocytes and peritoneal exudate polymorphonuclear leukocytes in MRL mice

Chemotactic responsiveness to fMet-Leu-Phe in concentrations of 10(-8) to 10(-4) M in the Boyden chamber was compared between peritoneal exudate cells (PEC) and polymorphonuclear leukocytes (PMN) isolated from peripheral blood, between MRL/Mp-+/+ (MRL-+/+) and MRL/Mp-lpr/lpr (MRL-lpr/lpr) mice, and between young (6-9 week old) and aged (16-24 week old) mice. Chemotactic responsiveness of PEC did not differ between MRL-+/+ and MRL-lpr/lpr, and young and aged mice. While, PMN showed greater chemotaxis in aged MRL-+/+ mice than that in aged MRL-lpr/lpr mice. These results suggest that chemotactic responsiveness of PMN differ from that of PEC which is assumed to be preactivated by an inflammatory agent injected into the peritoneal cavity to elicit cells. Less responsiveness of PMN to the bacterial origin peptide might relate to the autoimmune disease of this murine model.

Decreased plasma superoxide scavenging activity in immunological disorders--carboxyethylgermanium sesquioxide (Ge-132) as a promoter of prednisolone

We investigated so-called superoxide scavenging activity (SSA) of plasma in patients with several immunological disorders, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), polymyo-dermatomyositis (PM), progressive systemic sclerosis (PSS), myasthenia gravis (MG) and autoimmune thyroid disease (AT), using the electron paramagnetic resonance/spin trapping technique. Since carboxyethylgermanium sesquioxide, Ge-132, has been reported to modulate both the immune response and leukocyte functions, we have studied in vivo effect of Ge-132 on plasma SSA and other laboratory parameters in these disorders. The plasma SSA was significantly lower in RA, SLE, PM and PSS, but not in MG and AT, as compared with that in healthy controls. An inverse correlation was observed between plasma SSA and parameters such as erythrocytes sedimentation rates, absolute number of leukocytes, C-reactive protein and serum globulin levels. Furthermore, plasma SSA was significantly decreased in rheumatoid factor-positive patients as compared to negative patients. No correlation was observed between plasma SSA and factors such as ages, sex of patients or the other laboratory parameters, such as serum albumin, triglyceride, cholesterol, hemoglobin and serum iron levels. Patients treated with prednisolone, especially ones with RA, showed an increase of plasma SSA. It appears that Ge-132 promotes prednisolone effects. Our results indicate that a decrease in plasma SSA is not disease specific, but inversely correlates with the severity and activity of inflammation. The methodology to measure plasma SSA presented in this work provides a helpful tool for determining the actual activity of the diseases as well as in vivo studies of antiinflammatory agents.

Leukotriene B4 Production by Neutrophils from Patients with Rheumatoid Arthritis

Leukotriene B4 (LTB4) production by unstimululated and stimulated neutrophils from peripheral bloods of normal persons and rheumatoid arthritis patients and from rheumatoid arthritis synovial fluids were examined. Spontaneous production of LTB4 was observed in neutrophils from rheumatoid arthritis synovial fluids but not in peripheral blood neutrophils from rheumatoid arthritis and normal persons. Synovial fluid neutrophils produced significantly higher amounts of LTB4 than peripheral neutrophils of rheumatoid arthritis patients or normal persons, whether neutrophils were stimulated or not. Recombinant human IL-1B did not stimulate LTB4 production by neutrophils. Tiopronin, a SH group-containing compound, inhibited neutrophil LTB4 production.

These results indicate that LTB4 plays an important role in rheumatoid joint inflammation.

Rheumatoid factor modulation of neutrophil superoxide generation enhancing activity of preformed immune complexes

Heat aggregated human (HAG) IgG pretreated with total rheumatoid factors isolated from the serum of rheumatoid arthritis patients showed decreased superoxide generation enhancing activity as compared with HAG pretreated with buffer alone. Similarly, monoclonal IgM rheumatoid factor isolated from the serum of a patient with macroglobulinemia complicated by rheumatoid arthritis inhibited superoxide generation enhancing activity of HAG. On the other hand, superoxide generation enhancing activity of BSA-antiBSA immune complexes was not affected by preincubation with rheumatoid factors isolated from the sera of either rheumatoid arthritis patients or the macroglobulinemia patient. Rheumatoid factors isolated from rheumatoid arthritis serum were fractionated by high performance liquid chromatography and IgM-class and IgG-class rheumatoid factors were obtained. IgG-class rheumatoid factor significantly enhanced the superoxide generation enhancing activity of HAG, whereas IgM rheumatoid factor inhibited it. Rheumatoid arthritis sera showed significantly higher superoxide generation enhancing activity than normal sera. HAG preincubated with rheumatoid arthritis sera showed significantly lower superoxide generation enhancing activity than HAG preincubated with normal sera. These results suggest that factors inhibiting superoxide generation enhancing activity of HAG are present in rheumatoid arthritis sera, and that the responsible is IgM rheumatoid factor, whereas IgG rheumatoid factor enhances it. The factors that express superoxide generation enhancing activity in rheumatoid arthritis sera are suggested to be intermediate size immune complexes.