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Biomedical subjects

J Breton-Gorius

Publications and source records attributed to J Breton-Gorius.

At least 163 records · Page 9Linked to original sources
PubMed1978

Cytochemical distinction between azurophils and catalase-containing granules in leukocytes. I. Studies in developing neutrophils and monocytes from patients with myeloperoxidase deficiency: comparison with peroxidase-deficient chicken heterophils.

The neutrophils and monocytes of two patients with hereditary myeloperoxidase (MPO) deficiency lacked MPO activity as determined by light and electron microscopic cytochemical staining. With a technique employing neutral 3,3'-diaminobenzidine, azurophils of precursor and mature neutrophils were devoid of MPO whereas eosinophil, basophil, and platelet peroxidases exhibited normal activity. After incubation in alkaline DAB medium, which stains catalase, some small granules were strongly reactive in both immature and mature neutrophils and monocytes. These catalase-containing granules were distinct from all other categories of granules. Their number decreased with maturation. In the presence of cyanide or aminotriazole, peroxidatic activity could also be detected in ellipsoid azurophils, although large spherical granules remained unreactive. This peroxidatic activity is apparently not due to MPO inasmuch as it has been demonstrated that this protein is not synthesized in these patients. Thus, the significance of the last finding is unclear but suggests a heterogeneity of azurophil content. In contrast to human MPO-deficient cells, chicken heterophils naturally devoid of peroxidase are unable to produce hydrogen peroxide upon phagocytosis and were also devoid of catalase-containing particles. This observation suggests that catalase is involved in the control of the intracellular level of hydrogen peroxide in human cells.

Animals↗
PubMed1978

Synthesis of a peroxidase activity by the cells of hairy cell leukemia: a study by ultrastructural cytochemistry.

The nature of cells present in the blood, marrow, and spleen of patients with hairy cell leukemia is largely debated. These cells have been tentatively categorized on the basis of either monocytic or lymphocytic markers, and the accumulating data points to the fact that they share some characteristics of both cell types. Although hairy cells are known to lack myeloperoxidase-positive granules, present in normal human monocytes, we investigated the possible presence of other peroxidase activities differing from the granule-bound myeloperoxidase. The study was carried out with several methods based on the incubation of fixed and unfixed cells in the presence of diaminobenzidine and hydrogen peroxide. A peroxidase activity was found in hairy cells, located always in the endoplasmic reticulum but not in the Golgi apparatus or in any granule. By its cytochemical characteristics it appears to be closely related to that of tissue macrophages, activated blood monocytes, and other nonlymphocytic hematopoietic cells. This peroxidase is not found in lymphocytes with B or T phenotypes.

Histocytochemistry↗
PubMed1978

Beta thalassemia with reticulocytopenia: clinical, biochemical, and ultrastructural studies.

An unusual form of beta thalassemia is described in two children of unrelated families. Its main features are a severe anaemia with a low reticulocyte count associated with an erythroblastic hyperplasia; these characteristics indicate a completely ineffective erythropoiesis. The results of the study of haemoglobin synthesis performed on the bone marrow in vitro showed a greater imbalance in chain synthesis than that typically found in Cooley's anaemia. Ultrastructural studies revealed, in erythroblasts, all the features observed in Cooley's anaemia, although these features were more widely encountered. In addition, two peculiar findings were noted: (1) many inclusion bodies, which were partially or totally surrounded by smooth membranes, and which may indicate an autophagic phenomenon; and (2) a spongy appearance of the chromatin in rare erythroblasts of one of the two patients which resembled that found in congenital dyserythropoietic anaemia type I. These findings suggest that the great imbalance in the synthesis of the haemoglobin chain is responsible for the presence of an increased number of inclusion bodies and results in the death of nearly all the late erythroblasts. Furthermore, the present results point out the need for further study of the synthesis of the globin chains in atypical congenital dyserythropoietic anaemias.

Blood Cell Count↗
PubMed1977

[The presence of an endogenous peroxidase activity in hairy cell leukemia cells].

Mononuclear cells from hairy cell leukemia have been studied in three cases by ultrastructural immunocytochemistry. Cells have fairly detectable surface immunoglobulins, without monoclonal distribution however. In addition these cells have a peroxidatic activity which is revealed in the perinuclear space and strands of endoplasmic reticulum.

Cytoplasm↗
PubMed1976

The cellular distribution of erythrocyte and normoblast A1 and A antigens in normal and preleukemic states. An immunoelectron microscopy study.

A1 and A alloantigens were visualized on human erythrocytes and normoblasts by immunoelectron microscopy using peroxidase-coupled antibodies. Specimens were obtained from patients with preleukemia and associated antigen weakening, and from individuals with normal antigen values. Cells were fixed by glutaraldehyde and subsequently reacted with antibodies.

ABO Blood-Group System↗
PubMed1976

[Improved methods for the cytochemical demonstration of platelet peroxidase (author's transl)].

The variability of results to demonstrate the peroxidase of platelets has been attributed to an inhibition of the enzyme by glutaraldehyde. In order to eliminate this difficulty, two new methods have been employed prior to incubation in the diaminobenzidine medium: 1. Fixation was omitted. 2. Fixation was performed in a mixture of tannic acid-formaldehyde glutaraldehyde. With these two procedures, intense and reproducible peroxidase staining of human platelets and chicken thrombocytes was obtained. Only when the fixation procedure was omitted could the peroxidase of rat platelets be demonstrated histochemically. The importance of the detection the peroxidase as a marker enzyme of the megakaryocyte cell line and the relationships of this peroxidase with those of leukocyte peroxidases are discussed.

3,3'-Diaminobenzidine↗
PubMed1975

[Peroxidase activity of neutrophil granules in two cases of congenital myeloperoxidase deficiency].

The neutrophils and monocytes of two patients with hereditary myeloperoxidase deficiency lacked myeloperoxidase activity as determined by light and electron microscopic cytochemical staining. Using Graham-Karnovsky media, azurophils of neutrophils were devoid of peroxidase whereas all eosinophilic and basophilic granules exhibited normal peroxidase activity. After incubation in alkaline diaminobenzidine media which stains the catalase of microperoxisomes, some small granules were seen to be strongly stained in both immature and mature neutrophils. These small granules were distinct from all other neutrophilic granules which lacked a positive reaction. Only, in the presence of cyanide or aminotriazole, peroxidatic activity was also detected in some ellipsoid azurophils. This observation suggests that these substances activated an oxidase whose nature is discussed.

Basophils↗
PubMed1975

Partial myeloperoxidase deficiency in a case of preleukaemia. I. Studies of fine structure and peroxidase synthesis of promyelocytes.

The ultrastructural localization of peroxidase activity has been studied in the circulating neutrophils and in a neutrophilic series of bone marrow cells from a patient with preleukaemia. Light microscopic examination showed 36% of the polymorphonuclear leucocytes to be totally devoid of myeloperoxidase, while 50% were normally stained and 14% were slightly positive for this enzyme. Electron microscopic studies revealed considerable heterogeneity in the promyelocyte population, since the number of peroxidase-deficient azurophil granules was seen to vary from 0 to 100% in these cells. Thus, several types of promyelocytes were identified. One cell type, which resembled that seen in normal subjects, contained myeloperoxidase within its azurophil granules and also within the cisternae of the rough endoplasmic reticulum and Golgi complex. A second type of promyelocyte, which was at an early stage of development, lacked myeloperoxidase in its secretory apparatus. These cells contained two species of azurophil granules, the first of which was devoid of peroxidase activity whereas the other reacted positively. These observations suggest that the premature arrest of myeloperoxidase synthesis in the promyelocytes from a preleukaemic patient may give rise to several populations of circulating neutrophils which can exhibit varying contents of myeloperoxidase.

Adult↗
PubMed1975

Partial myeloperoxidase deficiency in a case of preleukaemia. II. Defects of degranulation and abnormal bactericidal activity of blood neutrophils.

A patient with a refractory anaemia preceding acute myeloblastic leukaemia had an increased susceptibility to infection due to Staphylococcus aureus. 36% of neutrophils lacked myeloperoxidase (MPO) activity and, in vitro, these polymorphonuclear neutrophils (PMN) had a defect of bactericidal activity against Staphylococcus aureus. Cytochemical studies of phagocytosis with the electron miscroscope have shown that the degranulation of primary granules (MPO+ or MPO-) was normal after phagocytosis of Escherichia coli which were normally lysed. A defective destruction of Staphylococcus aureus and Candida albicans was observed in some PMN with or without MPO activity, suggesting that MPO deficiency itself was not the only cause of this defect. In PMN which appeared normal, most MPO(+) granules were unable to fuse with the phagocytic vacuole containing intact germs even after 90 min of contact. There was, therefore, in addition to a partial MPO deficiency, a defect in cellular degranulation. This defect, the mechanism of which is unknown, may be in part responsible for the defective bacterial degradation.

Blood Bactericidal Activity↗
PubMed1975

Fine structural and cytochemical identification of microperoxisomes in developing human erythrocytic cells.

An alkaline diaminobenzidine (DAB) medium has been used to identify peroxidase activity in small granules (0.09 to 0.2 mu in diameter) present in all forms of maturing erythrocytic cells with the exception of erythrocytes. These granules, which were more frequent in proerythroblasts (from two to seven by thin section), were distinct from pleomorphic granules present in the close proximity to the Golgi apparatus. They were also distinct from ferritin molecules which were seen as aggregates in siderosomes of polychromatophilic erythroblasts. They often appeared in close association with the smooth membrane of the nuclear envelope. Optimal conditions for the visualization of these granules by incubation in alkaline DAB were obtained when the peroxidase activity of hemoglobin was reduced by addition of low concentrations of potassium cyanide. Lack of hydrogen peroxide in the incubation media completely inhibited the staining reaction of hemoglobin, while the positive reaction persisted in the granules. Aminotriazole in the incubation media prevented the staining of these organelles. These findings suggest that small granules seen in maturing erythroblasts contain catalase and that they correspond to microperoxisomes described in other tissues. The mechanism of their disappearance during reticulocyte maturation is unknown. The relationship between particulate catalase of erythroblasts and soluble erythrocytic catalase has not been elucidated.

3,3'-Diaminobenzidine↗
PubMed1972

Ultrastructural localization of peroxidase activity in human platelets and megakaryocytes.

Normal human platelets and megakaryocytes were examined for peroxidase activity by the diaminobenzidine (DAB) cytochemical technic. When the fixation and the incubation were adequate, a strong reaction was present in the dense tubular system of platelets suspended in plasma or spread on carbon. The black reaction product was ascribed to enzyme activity, since the reaction was completely eliminated when H(2)O(2) or DAB were omitted, or when H(2)O(2) was in excess. In addition, the reaction was inhibited by aminotriazole, cyanide and azide. In the human megakaryocytes, the reaction was localized in the endoplasmic reticulum including the perinuclear envelope. The Golgi complex and the clear vacuolar system were negative for the reaction. After platelet release, the reaction was always seen in the perinuclear space. The nature and function of the enzyme, as well as its possible relationships with catalase, are discussed.

Aniline Compounds↗