Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The disruption of the molecular organization of the plasma membrane of leukocytes by phagocytosable particles, or by agents such as surfactants, antibodies, phospholipase C, fatty acids and chemotactic factors, leads to a stimulation of the phagocyte oxidative metabolism. Concanavalin A (Con A) has been used as a tool to study the mechanism of this metabolic regulation. The binding of Con A to the surface of polymorphonuclear leukocytes (PMNL) or macrophages produces a rapid enhancement of oxygen uptake and glucose oxidation through the hexose monophosphate pathway (HMP). This is explained by an activation of the granular NADPH oxidase, the key enzyme in the metabolic stimulation. The effect of Con A is not due to endocytosed lectin, since Con A covalently coupled to large sepharose beads still acts as stimulant. The metabolic changes caused by Con A are reversible. If, after the onset of stimulation, sugars with high affinity for Con A are added to the leukocyte suspension, the activity of granular NADPH oxidase and the rate of respiration and glucose oxidation return to their resting values. The metabolic burst, while partially supressed by treatment of PMNL with iodoacetate, sodium flouride and cytochalasin B, is slightly increased by colchicine. Con A induces a selective release of granular enzymes (beta-glucuronidase, peroxidase, alkaline phosphatase) from PMNL, whereas no leakage of cytoplasmic enzymes is observed. The enzyme release is inhibited by iodoacetate and by drugs known to increase cell levels of cyclic AMP. Based on a current view of the mode of interaction between Con A and cell surfaces, a model of the metabolic disruption of leukocytes is presented.
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PMID:Concanavalin A as a probe for studying the mechanism of metabolic stimulation of leukocytes. 16 45

The parietal epithelium of Bowman's capsule has been analyzed by enzyme cytochemistry in kidneys of mice (C57BL/6J) from birth to 50 days of age. There is a greater tendency for cells in the central portions of the capsular crescent to be cuboidal in post-pubertal males than in pre-pubertal mice of either sex or in post-pubertal females where they are generally squamous; moreover, these heightened capsular cells have a distinct microvillous border. Cytochemical procedures were selected which might confirm the morphological suggestion that the cuboidal parietal epithelium possesses an absorptive capacity. The oxidoreductase activity of the mitochondria of the cuboidal cells of this layer is comparable to that of the columnar cells of the proximal convoluted tubule. The cytochrome oxidase activity of the mitochondria in both of these segments of the nephron is intense. This is in sharp contrast to the unreactive mitochondria in the squamous cells of the parietal epithelium. Furthermore, a striking heterogeneity in the degree of cytochrome oxidase activity is evident in the mitochondria of the cuboidal parietal cells as well as in the cells of the proximal tubules. In the former cells, active mitochondria were generally found near microvilli at the apical ends and in the areas of the basal infoldings whereas those in a central position were more frequently unreactive. The brush border of the cuboidal capsular epithelium had prominent alkaline phosphatase and aminopeptidase activities as has previously been observed in other brush borders. Functional capacity corresponding to the morphological and cytochemical specialization of the cuboidal capsular cells was demonstrated by their uptake of horseradish peroxidase. This exogenous protein tracer could be seen in apical vacuoles and phagosomes in the cuboidal parietal epithelium. The cytochemical resemblance of the cells of this epithelium to those of the proximal convoluted tubules suggests a similar involvement in resorption and perhaps in active transport. A possible relationship of this differentiation of the capsular epithelium to the proteinuria normal for adult male mice is discussed.
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PMID:Cytochemical correlates of structural sexual dimorphism in glandular tissues of the mouse. I. Studies of the renal glomerular capsule. 17 Dec 42

Immunoperoxidase staining for Regan isoenzyme of alkaline phosphatase was performed on cryostat sections of five human tumor tisssues. With a direct immunoperoxidase staining for the localization of Regan isoenzyme at the light and electron microscope levels, sections previously fixed with 0.05 M phosphate-buffered 4% paraformaldehyde were reacted with rabbit antisera to human placenta alkaline phosphatase conjugated to horseradish peroxidase. Comparison of conventional histochemistry and immunohistochemistry for Regan isoenzyme indicated that strong specific immunoperoxidase staining appeared on the cell membrane surface, and a diffuse one, in the cytoplasm of lung and colon cancer tissue cells showing L-phenylalanine-sensitive alkaline phosphatase. No immunoperoxidase reaction was obtained in tumor cells showing sensitivity to L-homoarginine or lacking aklaline phosphatase activity.
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PMID:Direct immunoperoxidase staining for Regan isoenzyme of alkaline phosphatase in human tumor tissues. 18 52

The distribution of lipid, glycogen, peroxidase, alkaline phosphatase and acid phosphatase has been studied in the cells of blood and bone marrow smears from young chickens. Chicken heterophil granules react differently from those of mammalian neutrophils. A strongly positive peroxidase reaction was given by developing erythrocytes in chickens, unlike mammals. The significance of these species differences is not yet clear.
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PMID:Histochemical observations on chicken blood and bone marrow cells. 18 94

The cells of four thymus glands, two at 12 weeks, one at 16 weeks and one at 22 weeks gestational age, were examined cytochemically for enzymic activity and for surface markers. The reactions for chloroacetate esterase, peroxidase, and alkaline phosphatase were negative and the reaction for nonspecific esterase was only weakly positive in some of the cells. In contrast, nearly all thymocytes at the 12th gestational week showed strong focal acid phosphatase (acP) activity. The number of acP-stainable cells and the staining intensity declined progressively. A high percentage of thymocytes in early fetal life express a complement receptor (CR); the proportion of CR-bearing cells decreased while cells forming rosettes with sheep erythrocytes (possessing erythrocyte receptors: ER) correspondingly increased during fetal life. Using a mixed rosette assay, up to 30% of the thymocytes at 12 weeks gestation were found to bear CR and ER simultaneously. The number of CR- and ER-positive cells also declined progressively with fetal age. These findings show that CR-positive, ER-negative thymus cells mature into CR-negative, ER-positive thymocytes via a CR-positive and ER-positive intermediate cell, indicating that mature ER-positive thymocytes do not originate from another cell line lacking CR. The changes in surface markers during early T cell maturation is relevant to certain lymphomas whose cells also show strong focal acP activity and also express both CR and ER. These lymphoma cells may correspond to fetal thymocytes or T precursor cells present in small numbers after birth.
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PMID:Simultaneous presence of receptors for complement and sheep red blood cells on human fetal thymocytes. 19 21

A sensitive, solid-phase enzyme immunoassay for the detection of immunoglobulin M antibodies to cytomegalovirus is described. The results of the enzyme immunoassay correlated well with those obtained by an indirect immunofluorescence method. Horseradish peroxidase proved to be a more sensitive label than alkaline phosphatase. Nonspecific reactions, occurring with commercially available cytomegalovirus antigens, could be avoided by using a nuclear antigen prepared from sonically disrupted nuclei of cytomegalovirus-infected cells.
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PMID:Solid-phase enzyme immunoassay for immunoglobulin M antibodies to cytomegalovirus. 19 77

In order to investigate the influence of the central nervous system on the functional differentiation of the fetal anterior pituitary gland, the pituitary gland of anencephalic and normal fetus was studied by the peroxidase-labeled antibody method for the localization of various hormones. The only abnormality of pituitary endocrine cells in anencephaly was a marked decrease of ACTH cells. In the normal development, ACTH appeared as the earliest hormone in 5 weeks. And all other hormones were seen in 13 weeks. The reason for the decrease of ACTH cells in anencephaly was speculated to be a suppression at an early developmental life. The experimental observations done in rats using MAM might support this speculation. The adrenal glands of anencephalus showed atrophy of the fetal cortex which was considered to correlate with the decrease in number of ACTH cells. Absence of the histochemical activity of alkaline phosphatase in the permanent cortex of anencephaly may indicate absence or inadequate stimulation by fetal ACTH. Further experimental studies in suppression of the central nervous system in early developmental life seemed to confirm the above speculation in functional differentiation of the fetal pituitary and adrenal glands.
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PMID:Functional prenatal development of anencephalic and normal anterior pituitary glands. In human and experimental animals studied by peroxidase-labeled antibody method. 19 43

The variation of lactate dehydrogenase, peroxidase, acid and alkaline phosphatase isoenzymes was studied in VERO cells inoculated with infectant and UV-inactivated herpes simplex virus type 1 (HSV--1). Infectant HSV--1 induced quantitative and qualitative modifications in isoenzyme patterns within the first 4 hours post inoculation (p.i.). The modifications caused by the UV-inactivated HSV--1 were similar, but appeared 8 hours p.i. The possibility of using isoenzyme modifications as rapid, sensitive and specific biochemical tests for virus detection and differentiation between infectant and inactivated virus is discussed.
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PMID:Isoenzymes of lactate dehydrogenase, acid phosphatase, alkaline phosphatase and peroxidase in monkey kidney cell cultures inoculated with herpes virus type 1. 20 14

Leucocyte alkaline phosphatase (LAP) was histochemically detected in 7 to 18% of cells in tissue culture lines derived from the peripheral blood or bone marrow of each of 5 patients with untreated acute myelogenous or monomyelogenous leukaemia and in 30% of the cells in a clonal line of a rat promyelocytic leukaemia. Following transfer to diffusion chambers intraperitoneally implanted into total body irradiated rats, LAP levels were detected in up to 92% of human and 80% of rat leucocytes. There was no associated morphologic differentiation. In rat leukaemia cells peroxidase and myeloid specific esterase also increased from tissue culture levels. Return of cells to tissue culture decreased enzymes to pre-implant levels. Addition of plasma or peritoneal fluid from irradiated rats to cells in tissue culture again induced LAP. In contrast, LAP was not increased under these conditions with cell lines derived from patients with acute lymphatic leukaemia, or Sezary cell leukaemia. These studies indicate that a humoral factor in peritoneal fluid and plasma of irradiated rats increases LAP in human as well as rat leucocytes.
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PMID:Leucocyte alkaline phosphatase elevation in human acute leukaemia derived cell lines cultured in diffusion chambers. 26 91

Clustering of lymphocytes around Reed-Sternberg cells was noticed in single cell suspensions made from viable Hodgkin's lymphoid tissue. Cytocentrifugation of the suspension showed that clustering also occurred around a smaller cell type, thought to be the precursor of the classical Reed-Sternberg cell. Time-lapse cine films taken of the clustering showed unceasing activity on the part of the lymphocytes migrating over the surface of the central cell. Reed-Sternberg cells were reacted with anti-monocyte serum using indirect fluorescence techniques. In its mature form at least, the Reed-Sternberg cell showed no activity with the antiserum. No immunoglobulin was detected in the Reed-Sternberg cell using fluorescence techniques, but a few Reed-Sternberg cells showed diffuse cytoplasmic staining using the peroxidase-labelled antibody technique. Membrane receptor tests showed the lymphocytes surrounding the Reed-Sternberg cell to be T-cells. After proteolytic enzyme treatment to free lymphocytes from the surface, the Reed-Sternberg cell bound IgG-coated red blood cells indicating a probable Fc receptor. Cytochemistry demonstrated weak non-specific esterase activity in a small minority of Reed-Sternberg cells, and absence of acid phosphatase, alkaline phosphatase and peroxidase. A subpopulation of lymphocytes with distinctive segmentation of the nucleus was noted. These were often to be seen participating in lymphocyte rosettes around the Reed-Sternberg cell.
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PMID:Rosetting and other reactions of the Reed-Sternberg cell. 32 44


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