NADPH-binding component of the respiratory burst oxidase system: studies using neutrophil membranes from patients with chronic granulomatous disease lacking the beta-subunit of cytochrome b558.

The NADPH-binding site of the respiratory burst oxidase system of neutrophils has been proposed to be either at a cytosolic component or at the beta-subunit of cytochrome b558. In this study, affinity labeling of resting and stimulated membranes, the latter having been assembled by all of the oxidase components from both membrane and cytosol, was carried out using [32P]NADPH dialdehyde (oNADPH). Stimulation of human neutrophils with PMA greatly increased O2(-)-generating activity and caused considerable translocation of the cytosolic components p47phox and p67phox. Nevertheless, PMA stimulation did not produce a labeled band which included positions at 47, 67, and approximately 32 kD. The most intense band reflected a molecular mass of 84 kD regardless of the state of activation, but a labeled band was never found near the beta-subunit (91 kD) of cytochrome b558. This 84-kD protein was further confirmed in neutrophils of 14 patients with gp91phox-deficient X-linked chronic granulomatous disease. These results indicate that the NADPH-binding component is not recruited from the cytosol, and also, that a membranous redox component besides cytochrome b558 must be involved in the NADPH oxidase system.

Involvement of p40phox in activation of phagocyte NADPH oxidase through association of its carboxyl-terminal, but not its amino-terminal, with p67phox.

Phagocyte NADPH oxidase, dormant in resting cells, is activated upon cell stimulation to produce superoxide anion, a precursor of microbicidal oxidants. Active NADPH oxidase is found on the membrane as an enzyme complex, composed of membrane-integrated cytochrome b558 (gp91phox and p22phox subunits) and two cytosolic factors (p47phox and p67phox), each of the latter containing two src homology 3 (SH3) domains. Recently, we radioactively identified a third cytosolic factor, p40phox, as a molecule that associates with p67phox in human neutrophils. Although it has been found that this p40phox protein is defective in patients with chronic granulomatous disease (CGD) who lack p67phox, evidence to functionally relate it to the NADPH oxidase system has hitherto been lacking. In this study, we raised separate antibodies against both the COOH- and NH2-terminal polypeptides of p40phox as well as against the COOH-terminal polypeptide of p67phox to examine the mode of interaction between p40phox and p67phox in a complex. The antibody against the COOH terminus of p67phox was able to communoprecipitate p40phox in conjunction with p67phox itself as was expected. Very interestingly, however, the antibody against the COOH terminus of p40phox completely dissociated the p67phox molecule from the p40phox-p67phox complex unit without any detectable coimmunoprecipitation of p67phox, despite their tight association, whereas that against the NH2 terminus of p40phox had absolutely no dissociation effect. Similar results were found regarding their effects on the O2-generating ability of cytosol in a cell-free activation system, i.e., inhibition was noted with the COOH terminus antibody but not with that for the NH2 terminus of p40phox. However, this dissociation did not affect the translocation of the cytosolic components including p47phox to the membrane. Once the NADPH oxidase was activated, the antibody for the COOH terminus did not show any inhibitory effect on catalysis by the activated enzyme. The stimulators of NADPH oxidase, MA and SDS, did not dissociate the p40phox-p67phox complex. These results provide the first demonstration that p40phox is practically involved in the activation of NADPH oxidase through the association of its COOH-terminal, but not its NH2-terminal, with p67phox.

Nucleoside-triphosphate binding of the two cytosolic components of the respiratory burst oxidase system: evidence for its inhibition by the 2',3'-dialdehyde derivative of NADPH and desensitization in their translocated states.

Affinity labeling of the two cytosolic components of the respiratory burst oxidase system, p49-phox and p63-phox, from resting porcine neutrophils was carried out with [32P]NADPH dialdehyde (oNADPH), [32P]oGTP and [32P]oATP. p49-phox and p63-phox showed 10-times higher affinities for both oGTP and oATP than for oNADPH, suggesting that they are nucleoside triphosphate (NTP)-binding proteins, rather than the NADPH-binding site of the oxidase. In addition, oNADPH markedly inhibited the affinity labeling of p49-phox with [32P]oGTP and [32P]oATP, well reflecting its inhibitory effect on the oxidase activity in the cell-free system, which was previously reported to propose the NADPH-binding site in a cytosolic component. Stimulation of porcine neutrophils with either myristic acid or phorbol myristate acetate resulted in great enhancement of the oxidase activity, and in considerable translocation of p49-phox and p63-phox. Nevertheless, the affinity labeling of the stimulated cell membranes in both cases revealed no labeled bands corresponding to molecular masses of 49 kDa and 63 kDa. p49-phox derived from the stimulated membranes had lost its [32P]oGTP binding ability in contrast with that from resting cytosol, suggesting that the NTP-binding sites of the two cytosolic components may be desensitized on NTP binding in their translocated states.

All-trans-retinoic acid induced enrichment of functionally normal neutrophils in vivo in a patient with acute promyelocytic leukemia.

A patient with resistant acute promyelocytic leukemia was treated with all-trans-retinoic acid (45 mg/m2 per day for 42 days) and obtained complete remission at day 14. Analysis of the neutrophils from the patient at day 7 demonstrated that they were indistinguishable from neutrophils from normal individuals as far as this is assessed by presently available functional tests. Furthermore, the degree of peroxidase positivity of neutrophils obtained from the patient was similar to control values. Thus, taken together with the hematologic features, all-trans-retinoic acid induces leukemic promyelocytes to become functionally normal neutrophils. This therapy is particularly suitable in obtaining complete remission in patients with acute promyelocytic leukemia with neutropenia with or without previous chemotherapy.

Myelodysplastic syndrome evolving into a myeloproliferative disorder: one disease or two?

We report two patients who had been initially diagnosed as having a myelodysplastic syndrome but subsequently progressed into a leukothrombocytosis state which mimicked a chronic myeloproliferative disorder. Both patients had anemia and mild neutropenia without thrombocytopenia at the time of their diagnosis of myelodysplastic syndrome, and dyshematopoietic features were present in the bone marrow. After treatment with vitamin D3 for 7 and 18 months, respectively, they developed leukothrombocytosis which responded to hydroxyurea. We speculate that these and other similar patients with this unusual course might constitute an entity distinct from the typical myelodysplastic syndromes or chronic myeloproliferative disorders.

In vivo effects of recombinant human granulocyte colony-stimulating factor on normal neutrophil function and membrane effector molecule expression.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is now undergoing clinical trials. We investigated the effects of rhG-CSF on the function of neutrophils in vivo in healthy volunteers. rhG-CSF (0.5 micrograms/kg) was injected subcutaneously for 6 consecutive days. The number of neutrophils in peripheral blood decreased transiently within an hour, and thereafter increased 2-10-fold compared to the control 6 to 8 h after injection. The circulating neutrophils remaining during this early neutropenic period showed increases in such functions as random motility, chemotaxis, phagocytosis and superoxide anion production. On the other hand, the function of neutrophils which increased 6 to 8 h after rhG-CSF injection was normal. No decrease of neutrophil function was observed following the use of rhG-CSF. CD33-positive cells increased 3 days after rhG-CSF administration. CD11a (LFA-1) expression on the membranes circulating neutrophils decreased 6 h after rhG-CSF administration. This phenomenon suggested that neutrophils adhered to the reticuloendothelial system during neutropenia, and that there was an influx of CD11a-negative mature cells into the circulatory pool thereafter. All our findings suggest that rhG-CSF enhances the function of normal neutrophils in vivo, and that it is effective against microbial infection very soon after administration.

A marked decrease in defensin mRNA in the only case of congenital neutrophil-specific granule deficiency reported in Japan.

A deficiency of defensins (human neutrophil peptides, HNP) has been previously demonstrated in two individuals with congenital neutrophil-specific granule deficiency (SGD), but its genetic basis is not well understood. We have studied another case of SGD, the only case reported in Japan, to elucidate the molecular basis of defensin deficiency. Using Western blot analysis, we showed for the first time that HNP-4, a novel human defensin, was also deficient in the patient's neutrophils. Northern blot analysis demonstrated that the defensin mRNA was absent in the bone marrow cells of the patient. Limited Southern blot analysis, using a defensin cDNA probe, did not reveal any differences in fragment patterns of the genomic DNA between the patient and the control. We propose that the defensin deficiency in our patient is a consequence of a marked decrease in defensin mRNA in neutrophil precursors. Our findings were consistent with a previous speculation suggesting that the SGD defect occurs at the level of transcription.

Fc gamma RI and Fc gamma RIII on polymorphonuclear leucocytes in cord blood.

Fc gamma RI and Fc gamma RIII expression on polymorphonuclear leucocytes in cord blood from seven normal infants was investigated by flow cytometry. Fc gamma R expression on fresh polymorphonuclear leucocytes in whole blood samples and in blood samples incubated with or without interferon gamma (IFN-gamma) for 48 hours was also studied. The percentage of Fc gamma RIII positive polymorphonuclear leucocytes in cord blood (73.3%) was significantly lower than that in adult controls (95.9%). The mean fluorescence intensity of Fc gamma RIII was significantly increased on cord polymorphonuclear leucocytes by the incubation with IFN-gamma. Fresh cord polymorphonuclear leucocytes expressed only a small amount of Fc gamma RI as adult polymorphonuclear leucocytes. The percentage of Fc gamma RI positive polymorphonuclear leucocytes induced with IFN-gamma was significantly higher in cord blood (62.3%) than in adult controls (30.3%). It is possible that decreased expression of Fc gamma RIII is a factor in the susceptibility of newborns to infection. High expression of Fc gamma RI stimulated with IFN-gamma in neonates could have a compensatory role against decreased immunological function.

[Fundamental and clinical evaluation of 9,3"-diacetylmidecamycin in pediatric field (author's transl)].

1. The dry syrup of MOM was administered orally to 17 patients mainly with heart diseases at doses of 10 mg/kg and 20 mg/kg. In 17 cases, the serum level was measured and in 4 cases, the urinary excretion rate including the metabolites of MOM. 2. The mean maximal concentrations were 0.54 mcg/ml at 30 minutes for the group of 10 mg/kg treatment and 0.33 mcg/ml at 1 hour for the group of 20 mg/kg treatment. The dose response was not observed obviously in both groups. 3. In each of the cases, the sum of excretion rates of metabolites in the 24-hour urine was about 1%. 4. MOM was administered clinically to 39 cases with respiratory tract infections and the overall efficacy rate was 85%. 5. In this study, 5 strains of S. pyogenes were isolated and the eradication rate was 60%. 6. Although severe side effects were not observed, gastrointestinal abnormalities like diarrhea and vomiting were seen in 3 cases. 7. Any pediatric patient did not refuse taking.

[Study of cefroxadine in pediatrics regarding clinical efficacy and serum levels (author's transl)].

Basic and clinical evaluations of cefroxadine were carried out in children, and the following results were obtained. 1. Cefroxadine 20 mg/kg was administered to 9 children with heart disease for the prophylaxis against infections before undergoing cardiocatheterization and cardioangiography, and serum levels were determined. Peak levels reached after 30 minutes in 4 of the 9 cases, with a mean peak level of 22.5 mcg/ml and after 1 hour in 5 cases, with a mean peak level of 16.2 mcg/ml. Half life was 3.1 hours in the former group in a 6-hour blood sampling (1.04 hours in a 2-hour sampling) while in the latter group it was 1.37 hours. 2. Clinical responses were evaluated in 56 children comprising 23 cases of pharyngitis, 8 of tonsillitis, 13 of scarlet fever, 10 of urinary tract infections and 2 of impetigo. Fifty of these cases had excellent and good responses showing a efficacy rate of 89.3%. 3. From 42 of the cases, 43 strains were isolated as causative organisms. Major organisms included 27 strains of S. pyogenes, 9 of E. coli and 3 of S. aureus. As for bacteriological responses, all strains were eradicated. 4. No severe side effects were observed except for diarrhea of 1 cases and eosinophilia of 2 cases. Furthermore, no children refused to take cefroxadine dry syrup.

[Changes in neutrophil counts and functions after the administration of recombinant human granulocyte colony-stimulating factor in a patient with chronic idiopathic neutropenia].

The cause of chronic idiopathic neutropenia (CIN) is unknown. Recently recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been purified. Many studies of effects of rhG-CSF on the patients with neutropenia have been undertaken. We examined changes in neutrophil counts and functions after the administration of rhG-CSF in a patient with CIN. Six hours after the intravenous administration of 40 micrograms of rhG-CSF, neutrophil counts were raised from 90 to 1570/microliters, and the increased neutrophils functioned normally; chemotaxis, phagocytosis and O2(-) generation. It is suggested that rhG-CSF is beneficial for the treatment of infection in patients with CIN.

[Effect of rhG-CSF in the treatment of multiple hepatic abscesses in chronic granulomatous disease].

A 19-year-old male was diagnosed as having chronic granulomatous disease (CGD) based on negative NBT reduction in January, 1988. He was admitted with a chief complaint of high fever in November, 1988. As abdominal echogram and CT scan established a diagnosis of multiple hepatic abscesses, he was treated with various kinds of antibiotics. Since the therapy was ineffective, the number of circulating neutrophils was decreased, and the abscesses further grew, intravenous drip infusion of rhG-CSF 100 micrograms was initiated in addition to several antibiotics (sulfamethoxazole-trimethoprim, rifampicin, isoniazide, etc). At day 3 on rhG-CSF, the fever began to resolve and on day 15 the body temperature fell below 37 degrees C. The hepatic abscesses also tended to decrease in size and the CT scan performed 2 months later (March 17), disclosed only calcification in the liver. The neutrophil function test indicated that superoxide anion (O2-) and hydrogen peroxide (H2O2) production was slightly increased during rhG-CSF therapy. Combination therapy with rhG-CSF and potent antibiotics showed a favorable therapeutic effect on CGD complicated by multiple hepatic abscesses as a fatal infection.

[Sweet's syndrome in patient with refractory anemia during recombinant human granulocyte colony stimulating factor therapy].

We present a patient with refractory anemia (RA) who developed Sweet's syndrome during the treatment of recombinant human granulocyte colony-stimulating factor (rhG-CSF). A 30-year-old man was admitted to the hospital for evaluation of anemia. He was diagnosed as MDS (RA). As a phase II study in MDS, rhG-CSF therapy was begun. Fever associated with cutaneous lesion developed over the left shoulder. Antibiotics showed no effects. Skin biopsy revealed Sweet's syndrome. This skin lesion disappeared thoroughly with discontinuance of G-CSF and administration of prednisolone. To examine whether Sweet's syndrome was related to the G-CSF therapy, we analyzed the effect of G-CSF on the function of patient's neutrophils. However, the function of patient's neutrophils was not activated by G-CSF administration.

[Improvement of respiratory burst by individual neutrophils from a patient with chronic granulomatous disease, type X91- under treatment by granulocyte colony-stimulating factor for multiple liver abscess].

A 20-year-old male with chronic granulomatous disease (CGD) was admitted with multiple liver abscesses. He had already been diagnosed as CGD, type X91-, when he was 10 years old. He was successfully treated with antibiotics and granulocyte colony-stimulating factor (G-CSF) combined with continuous drainage of abscess. Employing flow cytometry, respiratory burst by individual neutrophils was measured using 2', 7'-dichlorofluorescein. The fluorescence intensity in all individual neutrophils from the patient under G-CSF treatment was higher than the one without G-CSF. G-CSF can be one of effective therapies for infection in some patients with CGD such as X91-.

[Neutrophil dysfunction in chronic neutrophilic leukemia without rearrangements of bcr and immunoglobulin heavy chain genes].

A 67-year-old man was admitted to our hospital with abdominal distension due to hepatosplenomegaly. The peripheral blood revealed Hb content 6.5 g/dl, platelet count 4.7 x 10(4)/microliter, and WBC count 105.8 x 10(3)/microliter with 88% of mature neutrophils. The neutrophil alkaline phosphatase score was 421. Bone marrow aspiration revealed hypercellularity with increased megakaryocytes and myeloid hyperplasia. 46, XY, del 20(q 11) without Philadelphia chromosome was identified by cytogenetic study. The patient was diagnosed as having chronic neutrophilic leukemia and was successfully treated with busulfan, but he died of atypical mycobacteriosis about 20 months later. Analysis of neutrophil function demonstrated diminution of deformability, random mobility, and chemotaxis, but almost normal phagocytosis and bactericidal capacity. Southern analysis showed no rearrangements of breakpoint cluster region (bcr) gene and immunoglobulin heavy chain gene.