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Hydrogen peroxide production in chronic granulomatous disease. A cytochemical study of reduced pyridine nucleotide oxidases.

The ability of polymorphonuclear leukocytes (PMN) to produce H(2)O(2) in response to phagocytic stimulation was examined cytochemically using leukocytes from normal individuals and patients with chronic granulomatous disease (CGD). Normal PMN oxidized diaminobenzidine within the phagocytic vacuole by a reaction dependent upon endogenous H(2)O(2) and myeloperoxidase. CGD PMN failed to oxidize diaminobenzidine, which is consistent with the biochemical data showing a lack of H(2)O(2)-generating capacity. A plasma membrane enzyme (oxidase) activated by phagocytosis is capable of H(2)O(2) production in PMN. The localization of this oxidase activity was explored in CGD PMN using a cytochemical technique specific for H(2)O(2). The enzyme activity is stimulated by exogenous NADH, but not NADPH. Reaction product formation, indicative of activity of the oxidase, is dependent upon precipitation of cerium ions by the enzymatically generated H(2)O(2). The advantage of this approach is that enzyme activity of individual cells can be assessed, allowing determination of numbers of reactive cells in the population and their relative degrees of reactivity. NADH oxidase was found to be active both on the plasma membrane and within the phagocytic vacuoles of control PMN, whereas those cells from three CGD patients showed greatly reduced activity in both these sites. Assessment of the reactivity of individual cells showed the number of cells with oxidase activity in CGD to be significantly reduced when compared to control values. Additionally, of those cells that do react, a higher percentage of them are only weakly reactive. Omission of NADH from the incubation medium reduced the percentage of control cells showing enzyme activity but had no effect on CGD PMN, implying that the enzyme is not saturated with substrate in control cells, but in CGD the diminished enzyme is fully saturated. The defect may lie in the fact that in CGD patients there are fewer cells capable of peroxide generation, and a majority of these reactive cells produce only reduced amounts of this bactericidal agent.

3,3'-Diaminobenzidine↗

Subcellular localization of the large subunit of Mo1 (Mo1 alpha; formerly gp 110), a surface glycoprotein associated with neutrophil adhesion.

Mo1 alpha (formerly gp 110) is a neutrophil glycoprotein whose deficiency is associated with abnormalities in several neutrophil functions, including defects in adherence, chemotaxis, and phagocytosis. Examination of whole cells and subcellular components by the use of both immunological and electrophoretic techniques demonstrated that Mo1 alpha was located primarily in the specific granules but that a small portion was present in the plasma membrane, where it is exposed to the extracellular environment and can bind to anti-Mo1 antibody. During degranulation, Mo1 alpha is translocated from the specific granules to the plasma membrane, resulting in a 5-10-fold increase in the surface expression of this glycoprotein. These findings plus previous work suggest that plasma membrane-associated Mo1 alpha is needed for a normal interaction between neutrophils and underlying surfaces, and raise the possibility that the increase in surface adhesiveness of neutrophils that have discharged their specific granules might be due in part to the increase in the amount of Mo1 alpha in the plasma membranes of these degranulated cells.

Animals↗

Deficiency of a leukocyte surface glycoprotein (LFA-1) in two patients with Mo1 deficiency. Effects of cell activation on Mo1/LFA-1 surface expression in normal and deficient leukocytes.

Mo1, a phagocyte surface glycoprotein heterodimer, is involved in a number of phagocyte adhesion functions such as binding and ingestion of serum-opsonized particles, zymosan-induced degranulation, and superoxide generation. Deficiency of this antigen in humans has been associated with increased susceptibility to recurrent bacterial infections. The beta subunit of Mo1 is shared by another surface glycoprotein named LFA-1, which is involved in lymphocyte proliferation, cytolytic T cell, and natural killing activities. Two unrelated patients with Mo1 deficiency were found to be deficient in LFA-1 as well as in the common beta subunit. Investigation of lymphocyte functions in these two patients revealed normal mixed leukocyte culture-generated cytolytic T cell and natural killing activities and significantly reduced proliferative response to phytohemagglutinin. LFA-1-deficient cells also proliferated in response to soluble antigen and different alloantigens. These responses were partially blocked by anti-LFA-1 antibody. Whereas LFA-1 was undetectable by immunofluorescence and immunoprecipitation on the patients' resting T cells, significantly reduced (approximately 5% of normal) but detectable amounts of the heterodimeric LFA-1 antigen were found on mitogen and alloantigen-activated T cells. On granulocytes, Mo1 surface expression was also dependent on the state of cellular activation. The amount of surface Mo1 present on resting normal granulocytes increased by 3-10-fold following exposure to stimuli that induced degranulation, suggesting the presence of a major intracellular pool for this antigen. Analysis of subcellular fractions from granulocytes showed that intracellular Mo1 is located primarily in the specific granule fraction. Activated granulocytes had little or no increase in their surface expression of LFA-1 antigen. Deficient granulocytes had significantly increased numbers of Mo1 antigen expressed on the surface following stimulation with calcium ionophore (1 microM). However, the amount expressed continued to be significantly reduced compared with normal cells. Quantitation of surface Mo1 on granulocytes exposed to calcium ionophore (1 microM) showed that both parents in one family but only the mother in the other family had significantly reduced levels of Mo1, suggesting heterogeneity in the inheritance of this disorder. Whereas LFA-1 deficiency on lymphocytes was associated with normal alloantigen-induced cytolytic T cell and natural killing activities in these two patients, functions which were in part dependent on small amounts of detectable LFA-1 antigen, the Mo1 deficiency state led to significant defects in phagocyte adhesion functions. Hence, the clinical symptoms associated with this combined deficiency state reflect a more profound phagocyte than lymphocyte disorder.

Animals↗

Immunoglobulins in the hyperimmunoglobulin E and recurrent infection (Job's) syndrome. Deficiency of anti-Staphylococcus aureus immunoglobulin A.

Patients with the hyperimmunoglobulin E and recurrent infection syndrome (HIE) characteristically have frequent skin and respiratory infections caused by Staphylococcus aureus. We have developed a set of enzyme-linked immunosorbent assays that use whole S. aureus (Wood's strain) immobilized on 0.22-micrometers filters and highly specific, affinity-purified enzyme conjugates of goat anti-human IgE, anti-human IgD, anti-human IgG, anti-human IgA, and anti-human IgM. These reagents were used to determine S. aureus-specific immunoglobulin (Ig) levels. As previously published, 10 patients with HIE had markedly higher levels of anti-S. aureus IgE than did 5 patients with eczema and recurrent superficial S. aureus infections (P less than 0.001). The HIE patients were also found to have a deficit of anti-S. aureus serum IgA as compared with 12 normal subjects, 12 patients with chronic granulomatous disease, 5 patients with chronic eczema and recurrent superficial S. aureus infections, and 3 patients with the Chediak-Higashi syndrome (P less than 0.01 for each comparison). In addition the HIE patients had an excess of anti-S. aureus IgM as compared with normal subjects (P less than 0.01). An expected excess of anti-S. aureus IgG was absent. These abnormalities cannot be explained by variations of total serum Ig levels or by a general inability to produce antigen-specific IgA because levels of naturally occurring IgA antibody against Escherichia coli lipopolysaccharide and the antigens of the pneumococcal vaccine are normal. Parotid saliva from patients with HIE contained less salivary IgA per milligram of protein (P less than 0.01) and less salivary anti-S. aureus IgA per milligram of protein (P less than 0.05) than did normal controls. The incidence of infection at mucosal surfaces and adjacent lymph nodes correlated inversely with serum anti-S. aureus IgA (r = -0.647, P = 0.034), serum anti-S. aureus IgE (r = -0.731, P = 0.016), total serum IgE (r = -0.714, P = 0.020), and total serum IgD (r = -0.597, P = 0.049). These findings are evidence of a previously undescribed immunoregulatory defect in patients with HIE, which may contribute to the increased susceptibility to infection in this syndrome.

Adolescent↗

Metabolism of immunoglobulin E in patients with markedly elevated serum immunoglobulin E levels.

The metabolism of human IgE was studied in normals, severe atopics, and patients with the hyperimmunoglobulin E-recurrent infection (HIE; Job's) syndrome to determine whether IgE metabolism is altered in patients with marked elevation of serum IgE. Purified polyclonal 125I-IgE was administered intravenously and serial plasma and urine samples were obtained. After analysis, the metabolic data support previously published evidence that IgE (at concentrations found in normal individuals) is catabolized at a higher fractional rate than other immunoglobulins and is catabolized by both an intravascular and an extravascular pathway. In addition, the data show that the fractional catabolic rate for IgE is significantly less for the atopic patients (mean +/- SEM = 0.20 +/- 0.01) and for the HIE patients (0.15 +/- 0.02) than for the normal volunteers (0.52 +/- 0.06; P less than 0.01) and is inversely related (r = -0.851; P less than 0.001) to the serum IgE concentration. These findings have specific importance in showing that decreased fractional catabolic rate contributes substantially to elevation of IgE in atopic and HIE patients. In addition, the findings have general significance in that they lead to a unifying hypothesis of immunoglobulin catabolism.

Body Fluid Compartments↗

Urokinase-deficient and urokinase receptor-deficient mice have impaired neutrophil antimicrobial activation in vitro.

Leukocytes express both urokinase-type plasminogen activator (uPA) and the urokinase receptor (uPAR, CD87). We have shown that neutrophil recruitment to the lung during P. aeruginosa pneumonia is impaired in uPAR-deficient (uPAR-/-) mice but is normal in uPA-/- mice. However, both uPA-/- mice and uPAR-/- mice have impaired lung clearance of P. aeruginosa compared with wild-type (WT) mice. To determine the role of uPA and uPAR in antibacterial host defense, we compared neutrophil bacterial-phagocytosis, respiratory burst, and degranulation among uPA-/-, uPAR-/-, and WT mice. Neutrophil phagocytosis was significantly diminished comparing uPA-/- and uPAR-/- mice with WT mice at all time points. The generation of superoxide by both uPA-/- and uPAR-/- neutrophils was about half of that seen in WT neutrophils. Degranulation of azurophilic granules was significantly diminished in uPA-/- neutrophils compared with either uPAR-/- or WT neutrophils. By contrast, agonist-stimulated release of specific granules was not diminished in either uPA-/- or uPAR-/- mice compared with WT. We conclude that the uPA/uPAR system modulates several of the crucial steps in neutrophil activation that result in bacterial killing and effective innate host defense.

Animals↗

Multiple leukocyte abnormalities in chronic granulomatous disease: a familial study.

A variety of leukocyte enzyme activities were studied in an 11-year-old female with chronic granulomatous disease (CGD) and several members of her family. Leukocyte glucose-6-phosphate dehydrogenase (G-6-PD) activity was 17 nmol/min/mg protein in the patient; two brothers with symptoms of recurrent bacterial infections have G-6-PD activities of 58 and 37 nmol/min/mg protein; the activites of this enzyme in both parents, maternal grandmother, and one additional brother were within normal limits. Storage at 4 degrees or heating at 37 degrees over a 120-min period revealed a marked lability of G-6-PD activity in the patient's cells which could not be stabilized by the addition of NADP and 2-mercaptoethanol; this lability was not seen in other family members tested. Activities of leukocyte glutathione reductase were reduced in both parents and the two affected male siblings with values of 18, 23, 23, and 24 nmol/min/mg protein, respectively. Activities of leukocyte glutathione peroxidase were reduced in all of the immediate family members tested, with values ranging from 11.2 to 43 nmol/min/mg protein; the activity of this enzyme in the patient was 38.5. Leukocyte NADP content in the patient, father, and two affected male siblings were 16.5, 23.4, 22.2, and 28.2 nmol/15 min/10(7) leukocytes, respectively.

Adolescent↗

Metabolism of thyroxine and triiodothyronine in patients with chronic granulomatous disease.

Normal human leukocytes can degrade thyroid hormones in vitro especially during phagocytosis. To test whether the leukocyte system plays a significant role in hormone economy in vivo, studies of the metabolism of labeled T4 and T3 granulomatous disease, whose leukocytes had earlier been shown to have a reduced ability to degrade the thyroid hormones. Hormone turnover rates in the 3 subjects were similar to those reported for normal children by various investigarors. Also, normal ratios between fecal and urinary excretion of radioactivey were observed, suggested that deiodination was the major route of hormone breakdown, as it is in normal subjects. Our interpretations of these findings are: 1) an intact leukocyte hormone degrading system is not essential for normal rates of thyroid hormone metabolism in vivo; 2) the leukocyte defect in chronic granulomatous disease is not accompanied by a general defect in mechanism for thyroid hormone degradation in other tissues.

Adolescent↗

Polymorphonuclear leukocyte functions and multiple sclerosis.

We tested peripheral blood from 60 patients with definite multiple sclerosis (MS) and 60 healthy controls for polymorphonuclear leukocyte (PMNL) functions and found significant disorders in adherence (9.07% +/- 8.18% for patients versus 28.97% +/- 5.76% for controls), chemotaxis (18.32 +/- 3.1 for patients versus 30.49 +/- 4.52 for controls), phagocytosis (73.6 +/- 25.25 for patients versus 111.2 +/- 25.7 for controls), and bactericidal action (10.35% +/- 5% for patients versus 25.09% +/- 4.82% for controls). All differences were significant (p < 0.001). We confirmed the results by retesting 3 to 8 months later. The depressed PMNL functions in MS patients may explain their increased susceptibility to infections of the respiratory, digestive, and urinary tracts.

Adult↗

Respiratory syncytial virus infection in patients with phagocyte defects.

Patients with phagocyte defects frequently develop bacterial or fungal pneumonias, but they are not considered to be at increased risk for viral infections. We describe 3 patients with known phagocyte immunodeficiencies who developed lower respiratory tract infections (LRTI) caused by respiratory syncytial virus (RSV). All 3 patients had dense pneumonias as indicated by computed tomography scan of the lungs and RSV was recovered. We conclude that RSV can present as a dense pneumonia in patients with phagocyte defects. Along with common pathogens causing LRTI, RSV should be considered in the differential diagnosis. Viral cultures as well as rapid antigen detection assays for respiratory viruses should be included in the evaluation of LRTI in patients with phagocyte defects. respiratory syncytial virus, phagocyte, immunodeficiency, pneumonia.

Child↗