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D F Bainton

Publications and source records attributed to D F Bainton.

At least 91 records · Page 5Linked to original sources
PubMed1982

Identification of primary lysosomes in human megakaryocytes and platelets.

The presence of lysosomal enzymes in human platelets is well documented; the identity of the "lysosome," however, has been the subject of some disagreement. In order to determine the time of appearance and subcellular localization of two lysosomal enzymes in megakaryocytes (MK) and platelets, we examined normal human bone marrow and blood by electron microscopy and cytochemistry. Acid phosphatase (AcPase) was present in the Golgi region in the youngest recognizable MK, as well as in those with a considerable degree of cytoplasmic maturation. Heavy reaction product was usually confined to one or two Golgi-associated cisternae and coated vesicles; other Golgi cisternae were sometimes lightly reactive. In mature MK, reaction product was limited to vesicles of variable size, but smaller than alpha-granules. Another lysosomal enzyme, arylsulfatase (AS), was localized in similar small vesicles in MK of all stages; it could not be demonstrated in the Golgi complex. Vesicles containing AS were also found in about 25% of platelet profiles, whereas vesicles containing AcPase were found in only about 15% of platelet profiles. The alpha-granules of all MK and platelets examined were negative for both enzymes. We conclude that the enzyme-containing vesicles in these cells constitute the lysosomes and that they are distinct from other platelet organelles. Since there was no evidence that they had participated in any digestive event, we believe that they are primary lysosomes, whose contents are secreted during platelet aggregation and the release reaction.

Acid Anhydride Hydrolases↗
PubMed1982

Histochemistry of Hodgkin's disease.

The histochemistry of Hodgkin's cells is controversial. Limited numbers and the variety of techniques used make comparisons difficulty. Acid phosphatase and nonspecific esterase have been the two enzymes most frequently tested because the presence of these enzymes has been thought to be characteristic of histiocytes. Despite the controversial results, these studies have frequently figured prominently in arguments about the cell of origin in Hodgkin's disease. Authors identifying the presence of acid phosphatase and nonspecific esterase have generally favored a mononuclear phagocyte origin; those with negative results have favored a lymphoid origin. We have evaluated a series of 21 cases of Hodgkin's disease using tissues embedded in plastic and tested for acid phosphatase and nonspecific esterase. We found that Hodgkin's cells were frequently positive for acid phosphatase (20 to 21 cases) and/or nonspecific esterase (18 of 21). The reactions are weak and sensitive to inhibition by processing procedures. The reaction patterns are unusual for lymphoid cells and histiocytes. The finding is similar to that seen in interdigitating reticulum cells, a specialized cell found in the paracortex of human lymph nodes.

Acid Phosphatase↗
PubMed1981

Identification of alpha-naphthyl butyrate esterase as a plasma membrane ectoenzyme of monocytes and as a discrete intracellular membrane-bounded organelle in lymphocytes.

A reaction for an esterase, with a nonhalogenated, short-chain naphthyl ester (alpha-naphthyl butyrate or alpha-naphthyl acetate) as the substrate, has been used to identify mononuclear phagocytes by light microscopy. By analyzing techniques used in the collection, separation, fixation, processing, and embedding of human blood leukocytes for electron microscopy, we adapted the light microscopic method for use in determining the fine structural localization of this reaction. In monocytes, the reaction product covered the external surface of the plasma membrane. This distribution indicated that monocytic esterase is an ectoenzyme. The addition of NaF completely inhibited the monocytic reaction. In lymphocytes, the reaction product was localized in membrane-bounded intracellular organelles, similar to those previously shown to contain phospholipid and called Gall bodies. These organelles correspond with the punctate densities or focal reaction product observed by light microscopy. Other investigators believe that this distribution of enzyme in lymphocytes marks a subset of T cells, the Tmicro. The lymphocytic reaction was not inhibited by NaF.

Carboxylic Ester Hydrolases↗
PubMed1981

Differentiation of cell surface receptors on normal human bone marrow myeloid precursors.

Receptors for IgG and complement are present on the plasma membrane of functionally mature blood neutrophils. Neutrophilic precursors lack these membrane receptors, which may account for their diminished phagocytic capability. In this study, myeloid precursors from human bone marrow were examined for the presence and activity of membrane receptors for IgG and activated complement. Morphologic identification by light microscopy of neutrophilic cells are made by rosetting techniques and chloroacetate esterase cytochemical staining and at the ultrastructural level by peroxidase reactivity. This study showed the Fc receptor was the only membrane marker on the myeloblasts and that the number of cells with the receptor increased with maturation. Functional investigation of the Fc receptor indicated that its presence on early myeloid cells was insufficient to induce IgG-mediated ingestion. Phagocytosis via the Fc receptor was not acquired until the metamyelocyte stage. Complement receptors, C3d and C3b, appeared later than the Fc receptor. The C3d receptor, detected first on the promyelocyte, remained relatively constant throughout maturation, whereas the C3b receptor acquired acquired at the myelocyte stage increased with maturation. These data provide evidence that distinct membrane changes occur during normal myeloid cell maturation and that the presence of these membrane receptors is not sufficient for Fc-mediated ingestion to occur.

Bone Marrow↗
PubMed1981

Selective abnormalities of azurophil and specific granules of human neutrophilic leukocytes.

Human neutrophilic granulocytes (PMN) contain two chemically distinct granule types, which appear at different stages of maturation. The azurophilic granule (or primary granule) is formed during the promyelocyte stage and is known to contain myeloperoxidase in addition to numerous lysosomal enzymes, neutral proteases, glycoaminoglycans, cationic bactericidal proteins, and lysozyme. The specific granule (or secondary granule) is formed during the myelocyte stage. It is defined by the absence of peroxidase and has been shown to contain lysozyme, lactoferrin, and B12-binding proteins. The mature PMN contains both types of granules: 33% azurophilic and 67% specific granules. There are now a few well-documented examples of pathological PMN granulations that can be classified as a selective abnormality of one granule type or the other.

Cell Differentiation↗
PubMed1981

Ultrastructural localization of acid phosphatase in rosetted T and B lymphocytes of normal human blood.

Using electron microscopy and cytochemical techniques, the authors determined the distribution of acid phosphatase (AcPase) within the organelles of lymphocytes from blood rosetted with either neuraminidase-treated sheep erythrocytes (En) or sheep erythrocytes coated with antibody and complement (EACs). Subsequently, the various reactive organelles of the rosetted lymphocytes were counted, affording a comparison of T and B cells. It was found that AcPase was present in approximately 80% of T cells and 45% of B cells and was most frequently observed in secondary lysosomes of varying size and content. Although more T cells than B cells were reactive for AcPase, the extent of reaction in some B cells clearly precludes the use of AcPase for differentiating the two cell lines. It should be recognized that while the En rosetting procedure detects T cells in a nonselective manner, the EAC rosette is a marker of a major subpopulation of B lymphocytes, ie, those bearing complement receptors. We believe that the distribution of lysosomal enzymes in B and T lymphocytes probably reflects the functional state of individual cells rather than being a reliable indicator of cell lineage. A surprising finding (which could be established only by a fine-structural study) was the fact that 20% of circulating "resting" T cells contained reaction product for AcPase within endoplasmic reticulum and the perinuclear cisterna indicating that these cells are actively synthesizing AcPase, probably due to a foregoing inductive event. Such stimulus could be the result of recent endocytosis of surface receptors in combination with antigen, antibody, or immune complexes and/or recent mitosis, or possibly some unrelated autophagic incident.

Acid Phosphatase↗
PubMed1981

Enzyme histochemistry and immunohistochemistry on biopsy specimens of pathologic human bone marrow.

We have systematically investigated a variety of fixation and plastic embedding procedures and arrived at a method that allows processing of approximately 2-micron sections of bone marrow biopsies for examination by light microscopy. More importantly, this method permits the use of enzyme histochemical and immunohistochemical procedures that are rapidly becoming mandatory in the diagnosis of hematologic malignancies. Over 200 full-length bone marrow biopsy specimens were fixed in a mixture of paraformaldehyde, glutaraldehyde, and acrolein, dehydrated in acetone, and embedded in a mixture of methyl and glycolmethacrylate. All procedures were carried out at 4 degrees C. Decalcification was unnecessary. Sections 2-micron thick were cut and incubated for peroxidase, naphthol AS-D chloroacetate esterase, alpha-naphthyl butyrate esterase, acid phosphatase (with and without tartrate), or alkaline phosphatase and then examined by light microscopy. Specimens could be prepared for examination within 48 hr. This approach, which provides definitive markers for various hematopoietic cell lines in intact tissues, is invaluable when aspirated material is unavailable. It is also useful in the analysis of focal lesions of bone marrow due to inflammation or neoplasia and shows potential as an investigative tool. For example, we have discovered that early myelofibrosis is accompanied by a marked increase in the number of alkaline-phosphatase-positive reticulum cells.

Bone Marrow↗
PubMed1980

Degradation of connective tissue matrices by macrophages. III. Morphological and biochemical studies on extracellular, pericellular, and intracellular events in matrix proteolysis by macrophages in culture.

We have shown that macrophages in culture degrade the glycoproteins and amorphous elastin of insoluble extracellular matrices. Ultrastructural observation of the macrophage-matrix interaction revealed that connective tissue macromolecules were solubilized from the matrix extracellularly. At least part of the matrix breakdown was localized to the immediate vicinity of the cells, as shown by morphological and biochemical studies, although the rate of degradation correlated closely with the secretion of proteinases by various inflammatory stimuli in vivo, by glucocorticoids, prostaglandin E2 or colchicine, or by phagocytosis of latex, zymosan, or cholesterol-albumin complexes in culture was reflected in altered rates of glycoprotein and elastin degradation by the macrophages. Alteration of endocytosis and lysosomal digestion by cytochalasin B, NH4Cl, and proteinase inhibitors did not decrease the overall rate of matrix solubilization, but reduced the processing of the matrix fragments to peptides. Therefore, extracellular, pericellular, and lysosomal events each contribute to degradation of extracellular matrix macromolecules by inflammatory macrophages.

Connective Tissue↗
PubMed1980

Partial peroxidase deficiency in neutrophils and eosinophils associated with neurologic disease. Histochemical, cytochemical and biochemical studies.

Partial peroxidase deficiency was discovered by means of automated continuous-flow cytochemistry (Hemalog D) in the neutrophils and eosinophils of a patient admitted for evaluation of the gradual onset of intellectual deterioration. Wright's stain and routine benzidine peroxidase reaction on peripheral blood smears showed a normal differential count and peroxidase activity, respectively, but smears stained for peroxidase using 4-chloro-1-naphthol, the reagent used in Hemalog D, showed absence of enzymatic activity in neutrophils and eosinophils. Electron microscopy using the Graham-Karnovsky diamino-benzidine method confirmed these findings, demonstrating a new pattern of peroxidase deficiency in which a decreased number of peroxidase-positive granules were found in all neutrophils and, surprisingly, also in eosinophils. Bio-chemical studies also showed that the apparent deficiency is due to an abnormal proportion of "insoluble" peroxidase. These results and the clinical findings for the patient are consistent with the diagnosis of ceroid lipofuscinosis (Kuf's disease).

Bone Marrow↗
PubMed1980

Cytochemical localization of arylsulfatase B in rat basophils and mast cells.

Basophils and mast cells possess large metachromatically staining granules which contain sulfated glycosaminoglycans as well as vasoactive compounds. To determine whether these granules might also have lysosomal properties, we used electron microscopy and cytochemistry to localize arylsulfatase B in rat basophils and mast cells. In basophils of bone marrow, enzymatic reaction product was consistently seen in many, but not all, of the basophil granules. In some cells, the enzyme could also be demonstrated in the Golgi region, restricted to a single cisterna and small vesicles. It was never seen in rough endoplasmic reticulum (RER), although the paucity of cells made adequate sampling difficult. In mast cells of bone marrow and the peritoneal cavity, enzymatic reaction product was consistently found in some cytoplasmic granules of varying sizes and shapes where it characteristically rimmed the periphery of the granule just beneath the limiting membrane. It should be emphasized, however, that the majority of granules were not reactive. Reaction product could also be found occasionally in segments of RER, and in the Golgi region with a distribution similar to that of the basophil. The presence of lysosomal arylsulfatase in granules of developing basophils in bone marrow suggests that some basophil granules, like those of neutrophils, eosinophils, and monocytes are primary lysosomes. Some mast cell granules also contain this lysosomal enzyme, although it is not clear from the present data whether these granules are primary or secondary lysosomes.

Animals↗
PubMed1980

Electron microscopic and peroxidase cytochemical analysis of pink pseudo-Chediak-Higashi granules in acute myelogenous leukemia.

Giant round pink inclusions (congruent to 2 micrometers) were seen in neutrophilic myeloblasts, promyelocytes, and myelocytes from three patients with acute myelogenous leukemia. On preliminary examination of the bone marrow smears, these inclusions looked like ingested red blood cells in that they were pink and not azurophilic. The bone marrow specimens were processed for the electron microscopic demonstration of peroxidase with 3,3'-diaminobenzidine and H2O2 at pH 7.6. In all three cases, the inclusions were determined to be large peroxidase-positive granules since they were limited by a single unit membrane and, unlike endocytized red blood cells, were not contained within phagocytic vasuoles. The granules were homogeneously dense for peroxidase and showed no obvious crystalline structure when examined stained or unstained on grid. We believe that they correspond to the giant pink round granules Van Slyck and Rebuck observed in immature leukemic granulocytes in 1974 and termed the pseudo-Chediak-Higashi anomaly. Like the giant purple granules seen in leukemia with this anomaly, these granules also appear to be an abnormal variant of peroxidase-positive azurophil (primary) granules. Their lack of azurophilia is due to the absence of sulfated glycoaminoglycans.

Adolescent↗
PubMed1979

Association of alkaline-phosphatase-positive reticulum cells in bone marrow with granulocytic precursors.

In the bone marrow, an elaborate stroma forms the structural basis of the hemopoietic microenvironment. In this study, two different types of stromal cells were identified with certainty on tissue sections of intact bone marrow of rats and mice using light and electron microscopic histochemistry: (a) a fibroblast-type of reticulum cell which is characterized by having alkaline phosphatase associated with its plasma membrane. We refer to this cell as the alkaline-phosphatase-positive reticulum cell (Al-RC). It is closely associated with granulocytic precursors, particularly myeloblasts and neutrophilic promyelocytes. These reticulum cells may be found throughout the marrow but are concentrated near the endosteum. (b) a macrophage-type of reticulum cell which is characterized by its abundance of lysosomal acid phosphatase and is mainly associated with erythroid precursors (as observed by others). In contrast to the above-mentioned cell type, this latter cell was found to be distributed uniformly throughout the marrow. We speculate that the Al-RC are mesenchymal stromal cells necessary for granulocytic differentiation in bone marrow.

Acid Phosphatase↗
PubMed1979

Changing patterns of plasma membrane-associated filaments during the initial phases of polymorphonuclear leukocyte adherence.

By utilizing a combination of several ultrastructural techniques, we have been able to demonstrate differences in filament organization on the adherent plasma membranes of spreading and mobile PMN as well as within the extending lamellipodia. To follow the subplasmalemmal filaments of this small amoeboid cell during these kinetic events, we sheared off the upper portions of cells onto glass and carbon surfaces for 30 s--5 min. The exposed adherent membranes were immediately fixed and processed for high-resolution SEM or TEM. Whole cells were also examined by phase contrast microscopy, SEM, and oriented thin sections. Observed by SEM, the inner surface of nonadherent PMN membranes is free of filaments, but within 30 s of attachment to the substrate a three-dimensional, interlocking network of globular projections and radiating microfilaments--i.e., a subplasmalemmal filament complex--is consistently demonstrable (with or without postfixation in OsO4). Seen by TEM, extending lamellipodia contain a felt of filamentous and finely granular material, distinct from the golbule/filament complex of the adjacent adherent membrane. In the spread cell, this golbule-filament complex covers the entire lower membrane and increases in filament-density over the next 2--3 min. By 3--5 min after plating, as the PMN rounds up before the initiation of amoeboid movements, another pattern emerges--circumferential bands of anastomosing filament bundles in which thick, short filaments resembling myosin are found. This work provides structural evidence on the organization of polymerized contractile elements associated with the plasma membrane during cellular adherence.

Cell Adhesion↗
PubMed1979

Modification of hemoglobin H disease by sickle trait.

The rarity of hemoglobin (Hb) H disease in combination with sickle trait may be due in part to the absence of actual Hb H in individuals who, nonetheless, have inherited the deletion of three alpha-globin genes. We describe here a boy with persistent microcytic, hypochromic anemia despite adequate iron stores, who exhibited splenomegaly with a normal reticulocyte count and only rare inclusions in circulating erythrocytes. Starch gel electrophoresis and isoelectric focusing at age 5 yr showed 21% Hb S, persistent Hb Bart's, but no Hb H. Recticulocyte alpha/non-alpha globin chain synthesis ratio was 0.58 at age 5. The mother (Asian) had laboratory evidence of alpha-thalassemia trait and the father (Black) had sickle trait. The nature of alpha-thalassemia in this patient was investigated both by liquid hybridization and by the Southern method of gene mapping, in which DNA is digested with restriction endonucleases and the DNA fragments that contained the alpha-globin structural gene identified by hybridization with complementary DNA. The patient had only one alpha-globin structural gene, located in a DNA fragment shorter than that found in normal or alpha-thalassemia trait individuals, but similar to that present in other patients with Hb H disease. Morphologic studies of bone marrow by light and electron microscopy revealed erythroid hyperplasia with inclusions in polychromatic and orthochromatic erythroblasts, suggesting early precipitation of an unstable hemoglobin. The lack of demonstrable Hb H may be the result of both diminished amounts of beta(A) available for Hb H formation (since one beta-globin gene is beta(S)) and the greater affinity of alpha-chains for beta(A) than beta(S)-globin chains leading to the formation of relatively more Hb A than Hb S. The presence of a beta(S) gene may thus modify the usual clinical expression of Hb H disease.

Anemia, Sickle Cell↗