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PubMed1986

Monocyte nonspecific esterase: purification and subunit structure.

Monocyte nonspecific esterase has been purified from cultured cells of the acute myeloid leukemia cell line, ML-1. The purified enzyme shows the characteristic properties of the monocyte neutral serine carboxyl esterase, with high sensitivity to organophosphorus inhibitors and sodium fluoride inhibitor. The enzyme is a membrane protein which in the native state exists as a monomer of a mol wt of approximately 68,000 and a trimer of mol wt 205,000. These forms exhibit a complex pattern of dissociation and reassociation based on apparent noncovalent binding of subunits. The delipidated dissociated enzyme runs as a single protein chain of a mol wt of approximately 62,000 on sodium dodecyl sulfate (SDS) gel electrophoresis. The relation of the subunits to monocyte isoenzymes seen on isoelectric focusing (IEF) and polyacrylamide gel electrophoresis at pH 9.5 (pH 9.5 PAGE) of cell extracts is demonstrated. Availability of purified enzyme allows development of monoclonal antibodies and analysis of myeloid differentiation. In addition, the substrate specificity and function of the purified monocyte ectoenzyme are being examined.

Adult↗
PubMed1986

[Cytochemical study of acid naphthyl acetate esterase in the lymphocytes of healthy and bovine leukemia virus-infected cows].

A modified cytochemical technique was employed to investigate the unspecific acid naphthylacetate esterase of lymphocytes in the peripheral blood of a total of 64 clinically normal cows, having negative serologic and hematologic reaction for leukosis and of 42 cows with severalfold, well-manifested positive serologic response for the presence of the bovine leukosis virus with no changes in the hematologic data. With the normal animals an average of 6.86 per cent of the peripheral lymphocytes were found to be active--in the form of large dark-brown to dark red-brown granules--and such cells were considered to be T mu mature lymphocytes, while in 53.3 per cent of the cells activity was manifested in the form of tiny powder-like granules, and these were believed to be the Ty lymphocytes. Generally, 63.2 per cent were T-lymphocytes; the remaining 36.9 per cent of the cells had no activity typical for acid esterase, and these were considered to be B-lymphocytes. The study of cows with manifested agar gel immunodiffusion reaction for the presence of the bovine leukosis virus, with no lymphocytosis, revealed that there was a reliable rise of the T mu-lymphocytes up to 23.1 per cent, on an average, of the Ty-lymphocytes up to 69.2 per cent, while the percent of the B-lymphocytes dropped to 7.77 per cent, on an average.

Animals↗
PubMed1978

Tissue localization of T-lymphocytes by the histochemical demonstration of acid alpha-naphthyl acetate esterase.

Nonspecific acid alpha-naphthyl acetate esterase (ANAE) activity has previously been evaluated with the sheep erythrocyte (E) rosette assay and found to be a useful T-cell marker in cell suspension studies. T-lymphocytes display a solitary red brown nodule of reaction product (T-pattern) which can be readily distinguished from the diffuse, cytoplasmic staining of monocytes (M-pattern). Freshly obtained human tissue blocks were fixed with buffered formal sucrose and maintained in Holt's syrup; cryostat sections were cut and incubated under conditions appropriate for the histochemical demonstration of lymphocyte acid alpha-naphthyl acetate esterase activity. The results clearly demonstrate that T-pattern ANAE+ lymphocytes populate the paracortical and interfollicular regions of normal lymph nodes and tonsils and the periarteriolar sheaths of normal spleen, T-cell zones, while nearly every germinal center (B-cell area) lymphocyte is ANAE-. Macrophages and dendritic reticulum cells display diffuse cytoplasmic ANAE activity (M-pattern). Nodular malignant lymphomas (B-cell origin) are ANAE-; an E+ diffuse, cutaneous lymphoma was ANAE+. The histochemical demonstration of ANAE activity may represent the first reproducible, routine technique to localize T-lymphocytes in tissue sections.

Carboxylic Ester Hydrolases↗
PubMed1988

[Hirschsprung disease: histochemical technic for alpha-naphthyl-esterase in the intraoperative diagnosis of the proximal extent of the aganglionosis].

Intraoperative biopsies are required to confirm diagnosis of Hirschsprung's disease and to determine exact extent of aganglionism. Authors report a new method for enzymo-histochemical intraoperative evaluation of aganglionic segment. Activity of non specific esterase (following Davis and Orstein technique, 1959) has been used to demonstrate presence or absence of intramural ganglion cells in sero-muscular intestinal biopsies, which had been taken at various levels in 34 patients with preoperative diagnosis of Hirschsprung's disease. Authors consider histochemical technique as the most reliable, quick, simple and low-cost method for intraoperative evaluation of the length of aganglionic segment and, of course, to confirm diagnosis. Alpha-naphthyl-esterase is also of great help in the study of so-called pseudo-Hirschsprung.

Biopsy↗
PubMed1988

Structure and differential mechanisms of regulation of expression of a serine esterase gene in activated human T lymphocytes.

A cDNA clone encoding a polypeptide resembling proteolytic serine esterases (from cytotoxic T-cells; SECT) was isolated from human peripheral blood lymphocytes which had been cultured in the presence of the T-cell mitogen phytohemagglutinin for 72 h. The cDNA encodes a polypeptide of 247 amino acids which show homology of 99% with the protein sequence encoded by a cDNA clone (1-3E) isolated from staphylococcal enterotoxin A-stimulated human peripheral blood lymphocytes and 68% with the protein sequence (cytotoxic cell protease type I) derived from a cDNA clone (C11) encoding a serine esterase isolated from a murine cytotoxic T-cell line. The overall nucleotide sequence homology between the SECT cDNA and 1-3E was 99% and 73% between SECT and C11. Comparing the coding regions of SECT and C11 showed 75% homology, whereas the 5'- and 3'-untranslated regions showed 67% homology. Phytohemagglutinin stimulation results in 30-, 60-, and 370-fold increases in cytoplasmic SECT mRNA with respect to unstimulated cells after 6-, 24-, and 72-h cultures, respectively. At 6 h, the increase in SECT mRNA occurs in the absence of increases in SECT gene transcription and cytoplasmic mRNA stabilization. A 5-fold increase in SECT nuclear RNA seen at this time suggests that stabilization of SECT nuclear RNA transcript is responsible for early increases in SECT mRNA levels. At 24 and 72 h, the increased cytoplasmic SECT mRNA levels can be accounted for by increased transcriptional activity of the SECT gene.

Amino Acid Sequence↗
PubMedDate not supplied

Nonspecific esterase activity of human alveolar macrophages in routine cytology.

Alpha-naphthyl acetate esterase (ANAE) activity in alveolar macrophages was demonstrated in air-dried smears from samples of 82 sputa, 47 bronchial secretions and 14 bronchial lavages from 113 patients. Enzyme activity was estimated by a semiquantitative scoring method. There was a 7.4% loss of activity after 24 hours of storing the unfixed material, increasing to 14.4% after three days, while storing the air-dried smears for up to four weeks did not change the ANAE activity. The mean cellular esterase activity was correlated to the clinical and cytologic findings. A stringent correlation could be found for patients smoking more than 30 cigarettes a day; they had a 17% increase in activity as compared to nonsmokers. In patients with bronchial asthma, the activity was 18% higher than the total mean. In three patients with pulmonary embolisms, the ANAE activity was also increased. Treatment with a combination of cytostatics and a corticoid caused a severe decrease. No correlation could be found to age, sex, inflammation or malignant or cardiac diseases. These findings indicate that the application of the ANAE reaction to routine cytologic specimens can contribute to the functional characterization of human alveolar macrophages.

Asthma↗
PubMed1987

Antigen receptor-triggered secretion of a trypsin-type esterase from cytotoxic T lymphocytes.

Exocytosis of cytolysin-containing granules from cytotoxic T lymphocytes (CTL) was studied with the use of granule enzyme (BLT esterase) as a convenient biochemical marker. Using cloned CTL, we demonstrate here that BLT esterase secretion into the supernatant is specifically triggered by antigen-bearing target cells and that this secretion is inhibited by soluble monoclonal antibodies against the antigen-specific T cell receptor (TcR). Immobilized anti-receptor antibodies induced efficient enzyme secretion in the absence of target cells, thus implying a direct involvement of TcR complex in triggering exocytosis of granules. These results support the role of the granule exocytosis in CTL functions and provide a quantitative and direct assay of a rapid CTL functional response to antigenic stimulation.

Animals↗
PubMed1987

CTLA-1 and CTLA-3 serine esterase transcripts are detected mostly in cytotoxic T cells, but not only and not always.

We and other investigators previously reported the cloning of CTLA-1 (or CCP-1) and CTLA-3 (or H Factor) serine esterase-related transcripts preferentially expressed in cytolytic T lymphocytes. We extended the survey of the tissue specificity of these molecules. Two main sets of results were obtained. First, both CTLA-1 and CTLA-3 transcripts could be found in the various cytolytic T cells tested, although in widely different amounts, and in some cases just at the threshold of detection. Secondly, these transcripts were not found in most of the other cells tested, including in some natural cytotoxic cells and in activated cytotoxic macrophages; however, they could be detected in mast cells for CTLA-1 and in some noncytotoxic lymphocytes for CTLA-3. Thus, the CTLA-1 and CTLA-3 serine esterase products are most probably not required for macrophage or natural cytotoxicity; their presence cannot be taken as characteristic of cytotoxic T cells; and a discussion about their relevance to T cell-mediated cytotoxicity should take into account their widely different amounts from one cytotoxic T cell to another.

Animals↗
PubMed1986

Clinical uses of the leukocyte esterase test.

In summary, there are many current and potential uses of the leukocyte esterase dipstick. However, the studies in the literature supporting these uses have several methodologic problems that should make one cautious about relying on the test too heavily. Its use in the symptomatic patient should be secondary to a urinalysis, especially in those who as a group have significant sequelae from urinary tract infections. These include pregnant patients, diabetics, and geriatric patients who may be lacking signs and symptoms of infection. The dipstick is not meant as a replacement for the microscopic examination of the urine sediment; it should be used to direct one to examine urine specimens that would not normally be analyzed microscopically. Further studies controlling for symptoms and gender are needed to make the leukocyte esterase test more useful to the primary care physician.

Adult↗
PubMed1986

Inhibition of esterase activity and an undercounting of circulating monocytes in a population of production workers.

A cross-sectional review of routine employee health status examinations has identified an undercounting of circulating monocytes associated with an inhibition of a surface monocyte esterase, alpha-naphthyl butyrate esterase. It is postulated that this inhibition is associated with an organophosphate used in the production process. Correlation with routine measures of health status are presented.

Adult↗
PubMedDate not supplied

[Changes in the lipid levels of the liver, plasma, aorta and cholesterol esterase activity of the rat liver during exposure to tetrachloromethane].

Content of cholesterol esters was increased 2.3-fold, triglycerides--4.7-fold, phospholipids--1.5-fold in liver tissue of CCl4-treated rats. The increase in the content of cholesterol esters and triglycerides correlated with a decrease in activity of lysosomal cholesterol esterase from liver tissue. After CCl4 intoxication content of free cholesterol was decreased 2.1-fold, free fatty acids--2-fold, phospholipids--2.3-fold, triglycerides--1.75-fold in blood. In aorta an increase in content of cholesterol esters and triglycerides was found to be 2-fold as well as activation of the cytosolic cholesterol esterase was noted. The data obtained suggest that intoxication with CCl4 affected the accumulation of cholesterol esters in the arterial wall.

Animals↗
PubMedDate not supplied

[Effect of membranotropic agents on lysosomal acid cholesterol esterase of the rat liver].

An activity of acid cholesterol esterase was estimated in homogenate of liver tissue, lysosomal fraction and delipidated lysosomes using labelled cholesterol oleate contained in phospholipid liposomes. Taurocholate at the concentration of 2.6 mM increased the enzymatic activity but the mixture of taurocholate and Triton X-100 inhibited the enzyme. After addition of cholesterol the enzymatic activity and the activating effect of taurocholate were distinctly decreased. Alterations in the activity of acid cholesterol esterase and in the intalysosmal accumulation of cholesterol and of its esters may occur due to modifications of the substrate physical structure.

Animals↗
PubMedDate not supplied

[Effect of changes in the oxygen level on cholesterol esterase activity of the liver of intact rats and rats subjected to chronic hypoxia].

Alterations in activity of cholesterol esterases from lysosomal, microsomal and cytoplasmic cell fractions of rat liver tissue were studied under conditions of acute and chronic hypoxia and hyperoxia. Activity of the membrane-bound lysosomal and microsomal cholesterol esterases was decreased but the cytoplasmic enzyme was activated in acute hypoxia and hyperoxia. These data suggest that the enzymes, responsible for alterations in the ratio free cholesterol/cholesterol esters in cells, are dependent on the level of oxygen consumption.

Animals↗
PubMed1979

[Nonspecific esterase and alpha-glycerolphosphate dehydrogenase activity and the fat content in the regenerating chicken liver].

The data on histochemical study of changes in the activity of esterases, alpha-glycerophosphate dehydrogenase and the fat content in the chick regenerating liver are presented. The accumulation of the fat in hepatocytes during the early periods of regeneration (1--5th day of the experiment) is partially conditioned by the reduction of the activity of nonspecific esterases. The maximal liver steatosis is accompanied also by an increase in the activity of alpha-glycerophosphate dehydrogenase which indicates intensification of glycolysis and synthesis of triacylglycerines (liver spare lipids) during regeneration.

Animals↗
PubMed1968

Cholesteryl esterase and cholesteryl ester pools in corpus luteum.

Cholesteryl esterase activity has been demonstrated in the corpus luteum of the rat and the cow. The hydrolytic activity in bovine corpora lutea shows two pH optima, and is distributed throughout the particulate and supernatant fractions of the tissue. The greatest activity is present in the 5000 g pellet. The size of the available endogenous cholesteryl ester pools is also estimated. Some properties of the bovine luteal enzyme are different from those of pancreatic cholesteryl esterase from the same species.

Animals↗
PubMed1971

The nature of the reaction of organophosphorus compounds and carbamates with esterases.

This paper outlines our knowledge of the reaction of organophosphorus compounds and carbamates with esterases, examples of particular aspects of the reaction being confined to cholinesterases, although the general principles discussed apply to all B-esterases. Mathematical expressions are given for the different rate constants, and some of the factors that may affect the response of insect and mammalian cholinesterases to organophosphorus compounds and carbamates are discussed.

Acetylcholinesterase↗
PubMed1977

[Histochemical behavior of acetylcholinesterase in the diaphragm and that of unspecific esterase in the hypothalamus, testes and liver of rats in relation to organophosphates].

The enzyme behaviour of acetylcholinesterase in diaphragm and that of unspecific esterase in liver, testes and hypothalamus were investigated in view of various organophosphates on total-preparation and cryostat section of 10 male wistar rats. It had pointed out that the blockade was dependent upon the concentration as well as the acid possessing P = O-binding proved to be appropriate for in vitro experiment. The most intense blockade of unspecific esterase was reached in tanycytependym of the third ventricle. The acetylcholinesterase in the motor endplate of diaphragm was less influenced. From these findings follows that a direct conclusion for in vivo toxicity can not be drawn from in vitro results. The significance of the chemical structure of the substance utilized was discussed concerning its inhibitory effect.

Acetylcholinesterase↗
PubMed1977

Isozymic changes of acid phosphatase and esterase in regenerating rat liver after partial hepatectomy in relation to cell differentiation.

Activities and isozyme patterns of acid phosphatase and esterase were studied in rat liver at different intervals after partial hepatectomy to clarify the grade of immaturity of normal regenerating liver cells as a control for the unlimited proliferation of hepatoma cells. Acid phosphatase and esterase activities in the liver were elevated during a 12-hr period after hepatectomy, while their isozyme patterns did not change from those of immature liver. Similar findings were also observed in the liver of sham-operated rats. Eighteen hours after the operation, at the S phase before cell division, the isozyme pattern of these enzymes began to shift from an adult liver-type to an immature one resembling those of the infant liver 3 weeks after birth rather than those of newborn or fetal liver. Two or three days after partial hepatectomy, the isozymes characteristic of an immature liver type were more apparent. Although enzyme activities mostly returned to the normal adult level one week after the operation, the isozyme patterns did not completely return to those of an adult liver. These results indicate that despite the rapid proliferation of liver cells, the grade of cell differentiation of the regenerating liver after partial hepatectomy is much nearer to that of the normal adult liver rather than that of the fetal liver.

Acid Phosphatase↗

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