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Bone marrow prostatic specific antigen and prostatic acid phosphatase levels: are they helpful in staging prostatic cancer?

We analyzed serum and bone marrow levels of prostatic specific antigen and prostatic acid phosphatase quantified by double antibody radioimmunoassay in 70 patients. Of the patients 36 had prostatic cancer, including 23 with metastatic disease. There was a significant correlation between the serum and bone marrow levels of prostatic specific antigen and prostatic acid phosphatase independently of the metastases (p less than 0.001). No patient with prostatic cancer and positive bone marrow prostatic specific antigen or prostatic acid phosphatase levels had normal serum levels. Quantification of bone marrow prostatic specific antigen and prostatic acid phosphatase does not provide more information than does serum determination.

Acid Phosphatase↗

Antibody fragments as inhibitors of Japanese radish acid phosphatase.

VH (heavy-chain variable region) and VL (light-chain variable region) genes were amplified by PCR from hybridomas producing MAb-11 and MAb-18 which inhibited Japanese radish acid phosphatase. Nucleotide sequencing of the V genes demonstrates that the MAbs contained similar VH and identical VL domains. Initially, the VH and VL genes were expressed in Escherichia coli as single-chain Fv (ScFv) fragments. Fragments ScFv-11 and ScFv-18, named for MAb-11 and MAb-18, respectively, inhibited the enzyme activity to the same extent as the intact MAbs. Both of the antibody fragments widely cross-reacted with other phosphatases, including some phosphomonoesterases and phosphodiesterases from different sources. ScFv-18 also inhibited acid phosphatase from a different origin, but stimulated the activity of alkaline phosphatase from calf intestine. The PCR-amplified VH and VL genes were subsequently expressed separately in Escherichia coli as fusion products with glutathione S-transferase. The fusion proteins had little effect on Japanese radish acid phosphatase. Furthermore, a large number of recombinant ScFv fragments specific to the acid phosphatase were generated by using a bacteriophage expression system and a mouse ScFv gene library. These ScFv fragments had a range of effects on the enzyme activity, including inhibition, stimulation, and none. Among them, an ScFv fragment, designated ScFv-G7, inhibited more strongly than ScFv-11 and ScFv-18.

Acid Phosphatase↗

Electron microscopic cytochemical studies on acid phosphatase activity in acute myocardial ischemia.

Alterations in the localization and the intensity of acid phosphatase activity were studied electron microscopically in acute ischemic myocardial cells in the dog, in relation to processes of cellular degradation. In normal myocardial cells, the acid phosphatase activity was concentrated in the terminal cisternae, the longitudinal elements and the subsarcolemmal cisternae of the sarcoplasmic reticulum and the primary lysosomes. Activity was moderate in the secondary lysosomes, residual bodies and Golgi apparatus. As early as 15 min after coronary ligation the intensity of acid phosphatase activity increased in the enlarged lysosomes and the sarcoplasmic reticulum of the ischemic myocardial cells. Fine deposits of the reaction product were distributed in the sarcoplasm around lysosomes and the sarcoplasmic reticulum after 30 min, and the activity began to decrease in lysosomes and in the sarcoplasmic reticulum. One to 3 hours after ligation, intramitochondrial dense deposits appeared, and the reaction product decreased both in lysosomes and the sarcoplasmic reticulum. The fine reaction product, which leaked from lysosomes and the sarcoplasmic reticulum, was scattered in the sarcoplasm and was accompanied by fine structural changes indicating cellular necrosis. From these findings it is strongly suggested that acid hydrolases in lysosomes and the sarcoplasmic reticulum are closely related to the necrotic process in ischemic myocardial cells.

Acid Phosphatase↗

Molecular cloning and sequence analysis of cDNA encoding human prostatic acid phosphatase.

lambda gt11 clones encoding human prostatic acid phosphatase (PAP) (EC 3.1.3.2) were isolated from human prostatic cDNA libraries by immunoscreening with polyclonal antisera. Sequence data obtained from several overlapping clones indicated that the composite cDNAs contained the complete coding region for PAP, which encodes a 354-residue protein with a calculated molecular mass of 41,126 Da. In the 5'-end, the cDNA codes for a signal peptide of 32 amino acids. Direct protein sequencing of the amino-terminus of the mature protein and its proteolytic fragments confirmed the identity of the predicted protein sequence. PAP has no apparent sequence homology to other known proteins. However, both the cDNA clones coding for human placental alkaline phosphatase and PAP have an alu-type repetitive sequence about 900 nucleotides downstream from the coding region in the 3'-untranslated region. Two of our cDNA clones differed from others at the 5'-ends. RNA blot analysis indicated mRNA of 3.3 kb. We are continuing to study whether acid phosphatases form a gene family as do alkaline phosphatases.

Acid Phosphatase↗

A cytochemical scanning electron microscopy study of non-specific acid esterase and acid phosphatase activities in human peripheral blood lymphocytes.

We analyzed the distribution patterns of nonspecific acid esterase and acid phosphatase activities with cytochemistry-scanning electron microscopy in backscattered and secondary electron imaging modes in isolated normal human peripheral blood lymphocytes. The analysis of non-specific acid esterase activity in the backscattered electron imaging mode showed, in some cells, focal distribution with a well-defined, homogenous deposit. Two patterns of acid phosphatase activity were evident with the backscattered electron imaging mode, i.e., focal and granular. Peripheral blood lymphocytes showing focal activity of both enzymes presented a smooth surface with few scattered microvilli as seen with the secondary electron imaging mode; while lymphocytes with a granular pattern of acid phosphatase activity had abundant microvilli. The correlation between patterns of enzymatic activity as seen in backscattering electron imaging mode, and surface morphological features as seen with secondary electron imaging mode, distinguished a subpopulation of lymphocytes of T lineage in human peripheral blood.

Acid Phosphatase↗

Ultrastructural localization of tartrate-resistant acid phosphatase activity in rat osteoblasts.

Ultrastructural localization of tartrate-resistant acid phosphatase (TRAP) activity in metaphyseal osteoblasts of young rats was detected and compared with the localization of tartrate-sensitive acid phosphatase (TSAP). TRAP activity was detected in lysosomes and Golgi complex, such as Golgi lamellae, vacuoles and vesicles. TSAP, detected as beta-glycerophosphatase, was also located in Golgi lamellae, vacuoles and vesicles, and in lysosomes. Based on the ultrastructural features of TRAP-positive structures and the similarity of the distribution patterns of TRAP and TSAP, it is suggested that TRAP co-exists with TSAP, and is located in lysosomes and secretory granules in osteoblasts.

Acid Phosphatase↗

A unique acid phosphatase location: the transverse tubule of avian fast muscle.

Acid phosphatase activity was localized cytochemically in the posterior latissimus dorsi muscle of the chicken. Reaction product was observed in three distinct structures: T-tubules, sarcoplasmic reticulum and dense bodies. Examination of cross- and longitudinal sections confirmed that the reaction product was membrane-limited. Acid phosphatase activity was observed in sarcoplasmic reticulum adjacent to the A-I junction and the A-band, in termyofibrillar dense bodies located along the length of the fibre and in the T-tubules but not in the surface caveolae or in the lateral sacs of the sarcoplasmic reticulum. The uniqueness of the T-tubular localization with respect to cytochemical localizations in other muscles is discussed.

Acid Phosphatase↗

Toxicology of cupric salts on honeybees. V. Gluconate and sulfate action on gut alkaline and acid phosphatases.

Some aspects of putative nontarget effects of cupric ions systemically fed to honeybees against their parasite mite Varroa jacobsoni have been investigated on the host phosphatases. The alkaline and acid forms extracted from the guts of worker bees exhibited substrate-inhibition features. Upon detailed kinetic analysis, cupric organic salts indicate activation effects at concentrations of about 1 mM. Concentrations up to 10 mM (alkaline form) and 25 mM (acid form) induced no important changes, except a partial quenching of the substrate-inhibition process, characterized by a wide increase in the constant of apparent inhibitory binding of substrate to the enzyme-substrate complex. Partial purification gave a single alkaline form with quite similar kinetic behavior in the absence of natural ions as in crude extracts. Cupric gluconate and sulfate demonstrated similar patterns, except an increase of the apparent Hill coefficient by sulfate only. The substrate constant of acid phosphatases was decreased at high cupric gluconate doses while its maximum velocity was biphasically increased (with observed maximum at 1 mM), resulting in a sustained activation. Chemiluminescence studies revealed that cupric ion activation is counteracted by oxygen radicals generated by cupric ions and also, in vitro, by the artificial substrate para-nitrophenylphosphate. The para-nitrophenol molecules released from the reaction are therefore responsible for biphasic effects selectively observed with gluconate salts. In apicultural practice, neither blockade of activity nor dramatic changes are to be expected at doses administered to bees against the parasite.

Acid Phosphatase↗

Induction by morpholine of lysosomal alpha-mannosidase and acid phosphatase in rabbit alveolar macrophages in vivo and in vitro.

alpha-Mannosidase and acid phosphatase were induced in alveolar macrophages from the lungs of rabbits following exposure to morpholine. The induction was observed after inhalation of morpholine vapor or when macrophages were cultured in the presence of morpholine. Lysosomal hydrolases were not induced uniformly. In vivo, maximum induction of alpha-mannosidase and acid phosphatase in female rabbits was 1.7-fold and 2-fold, respectively, and in male rabbits, 3-fold and unchanged, respectively. In vitro, maximum hydrolase induction of alpha-mannosidase and acid phosphatase in macrophages from male rabbits was 1.4-fold and 1.3-fold, respectively, and from female rabbits, 1.3-fold and 1.5-fold, respectively. The induction of acid hydrolases in vitro was rapid, reaching a maximum within 4 hr in alveolar macrophages from male rabbits and within 8 hr in those from females. The induction was dose dependent. This study indicates that the lysosomal enzyme system of the alveolar macrophage may be stimulated by a low molecular weight xenobiotic.

Acid Phosphatase↗

Endocytosis of low density lipoproteins in human endothelial cells: typical morphological aspects of the high affinity receptor-mediated pathway as revealed by serial sections and acid phosphatase cytochemistry.

We used electron microscopy serial sections and acid phosphatase cytochemistry to follow the endocytosis of low density lipoproteins (LDL) by cultured human umbilical vein endothelial cells. The surface LDL-receptors were labeled with LDL-colloidal gold conjugates at 4 degrees C and then, cells were incubated for 0, 5, 10, 20, 30 and 60 min at 37 degrees C before fixation. The organelles identified in this way and studied by serial sections corresponded to those described in endothelial cells and in other cell types, with a peripheral endosomal compartment and a juxtanuclear endosomal compartment, located in the vicinity of the Golgi apparatus and mainly composed of round vesicle-containing structures called multivesicular bodies. By acid phosphatase cytochemistry, the limits between the endosomal juxtanuclear compartment and the lysosomal compartment were also studied and it was shown that multivesicular bodies are probably the first site for the acquisition of acid hydrolases. Lastly, the observation of highly gold-labeled endothelial cells when cells were incubated for 90 min at 37 degrees C with the LDL-gold conjugate, suggested that LDL was degraded in the lysosomal compartment.

Acid Phosphatase↗

Alteration of the cell surface acid phosphatase concomitant with the morphological transformation in Trypanosoma cruzi.

Acid phosphatase activity in Trypanosoma cruzi was found to be located on the external surface of the plasma membranes. Both specific activity and activity per cell of this bound enzyme were significantly higher in the cells of amastigote (an intracellular form) than that of trypomastigote (a bloodstream form) and epimastigote (culture form). During the transformation of epimastigotes to amastigotes in vitro the activity of surface acid phosphatase was elevated concomitant with the increase in population of amastigotes. These results were interpreted as that the elevated enzyme activity is required for the intracellular parasitization of this organism or is a consequence of the morphological transformation.

Acid Phosphatase↗

Acid phosphatase in prostatic tissue homogenates from patients with benign prostatic hyperplasia and prostatic carcinoma.

Acid phosphatase activity biochemically in the primary tumor of 20 patients with prostatic carcinoma, was studied in an attempt to understand the basis for a correlation or lack of correlation between serum and/or bone marrow acid phosphatase levels and the presence and/or clinical behavior of prostatic carcinoma. The enzyme activity was similarly measured in 19 patients with benign prostatic hyperplasia as controls. On the average, enzyme activities were lower (P less than 0.002) in the tissues from patients with carcinoma. There was no correlation of enzyme activity in tumor with the age of the patient, stage of disease, degree of differentiation of the tumor, or serum acid phosphatase activity.

Acid Phosphatase↗

Acid phosphatase activity in the wild-type and B-mutant hyphae of Schizophyllum commune.

In the wild-type and B-mutant hyphae of Schizophyllum commune, acid phosphatase activity was found in association with vacuoles, lipid bodies, and endoplasmic reticulum. Small granules containing acid phosphatase also occurred in mitochondria and along the nuclear envelope. Both ultrastructural and biochemical studies indicated greater acid phosphatase activity in the B-mutant than in the wild-type hyphae, which suggests that the mutation in the B incompatibility factor increases the production of the acid phosphatase in the mutant hyphae.

Acid Phosphatase↗

Induction of acid phosphatase activity during germination of maize (Zea mays) seeds.

Acid phosphatase activity (orthophosphoric-monoester phosphohydrolase, EC 3.1.3.2) increased during the first 24 h of maize (Zea mays) seed germination. The enzyme displayed a pH optimum of 4.5-5.5. Catalytic activity in vitro displayed a linear time course (60 min) and reached its half maximum value at 0.47 mM p-nitrophenyl phosphate (pNPP). Phosphatase activity towards phosphoamino acids was greatest for phosphotyrosine. The phosphatase activity was strongly inhibited by ammonium molybdate, vanadate and NaF and did not require divalent cations for the catalysis. The temperature optimum for pNPP hydrolysis was 37 degrees C. Under the same conditions, no enzyme activity was detected with phytic acid as substrate. Western blotting of total homogenates during seed germination revealed proteins/polypeptides that were phosphorylated on tyrosine residues; a protein of approximately 14 kDa is potentially a major biological substrate for the phosphatase activity. The results presented in this study suggest that the acid phosphatase characterized under the tested conditions is a member of the phosphotyrosine phosphatase family.

Acid Phosphatase↗

The Aspergillus nidulans pyrG89 mutation alters glycosylation of secreted acid phosphatase.

The glycosylation level of the pacA-encoded acid phosphatase secreted by Aspergillus nidulans was reduced in strains pabaA1 pyroA4and pabaA1 pyroA4 pyrG89, compared to strains carrying these mutations singly. The molecular mass of the enzyme secreted by the triple mutant grown at pH 5.0 was 105 and 45 kDa as determined by exclusion chromatography and SDS-PAGE, respectively. In contrast, the pabaA1 strain secreted acid phosphatases of 119 and 62 kDa. The enzyme also had an altered electrophoretic mobility and glycosylation had a protective effect against its heat inactivation. Thus, this combination of mutants alters glycosylation of the enzyme, leading to changes in their structural properties. In spite of this, no deviation was observed in the apparent optimum pH and Michaelis kinetics for enzymatic hydrolysis of p-nitrophenyl phosphate or alpha-naphthyl phosphate.

Acid Phosphatase↗

The effect of tartrate on bone cell acid phosphatase activity: a quantitative cytochemical study.

Tartrate-resistant acid phosphatase activity (TRAPase) is widely used as a cytochemical marker to distinguish osteoclasts from macrophages and other related cell types. The degree of tartrate resistance, however, may depend on which reaction methods, tissues, or species are used. To investigate this further, we have measured the amount of cytochemical reaction product by microdensitometry. We compared osteoclast acid phosphatase (APase) activity in fresh frozen sections of neonatal rat calvaria using two different reaction methods; one is commonly employed for qualitative histochemistry and includes alpha naphthyl phosphate as substrate, simultaneous coupling to the chromagen Fast Garnet, and a 30-minute reaction time (method A). The other may be used to measure enzyme reaction rates in cells in situ and employs conditions suitable for initial velocity kinetics, namely naphthol-ASBI phosphate as substrate, post coupling to Fast Garnet, and a 2-minute reaction time. Although enzyme reaction rates differed greatly between the two methods, significant inhibition of APase activity by tartrate was observed in calvarial osteoclasts (69% and 59% with methods A and B, respectively), osteoblasts, and spleen macrophages. Using method B, mouse calvarial osteoclasts had similar APase activity to that seen in the rat. Tartrate produced little inhibition in these mouse cells, in contrast to the observations made with rat tissue, but murine spleen macrophages were significantly tartrate sensitive (40% inhibition with tartrate). On this basis, conclusions regarding the cell specificity of TRAPase should be treated cautiously.

Acid Phosphatase↗

Prostatic acid phosphatase by radioimmunoassay. Sensitivity compared with enzymatic assay.

Prostatic acid phosphatase values in 98 patients with prostatic carcinoma were measured by a commercial radioimmunoassay (RIA) and by enzymatic assay. Forty-three carcinomas were staged by rigorous pathological criteria. Patients (N = 129) with benign prostatic hyperplasia were the control group. At 94% specificity, sensitivities of the RIA vs the enzymatic assay for clinically staged patients were as follows: stage A, 22% vs 6%; B, 29% vs 10%; C, 52% vs 38%; and D, 87% vs 80%. However, none of the seven patients with pathological stage A and B disease had a positive test result, and we suggest that variability in staging criteria accounts for the discrepant sensitivity claims reported. Prostatic acid phosphatase RIA should not be used for screening but as an adjunct for staging known prostatic carcinoma.

Acid Phosphatase↗

Effect of methanol on the activity and conformation of acid phosphatase from the prawn Penaeus penicillatus.

Prawn (Penaeus penicillatus) acid phosphatase (EC 3.1.3.2) catalyzes the nonspecific hydrolysis of phosphate monoesters. The effects of some pollutants in sea water on the enzyme activity results in the loss of the biological function of the enzyme, which leads to disruption of phosphate metabolism in cells. This paper analyzes the effects of methanol on the activity and conformation of prawn acid phosphatase. The results show that low concentrations of methanol can lead to reversible inactivation. Inhibition of the enzyme by methanol is classified as non-competitive inhibition, and the inhibition constant (Ki) is 8.5%. Conformational changes of the enzyme molecule in methanol solutions of different concentrations were measured using fluorescence emission, differential UV-absorption, and circular dichroism spectra. Increased methanol concentrations caused the fluorescence emission intensity of the enzyme to increase. The ultraviolet difference spectra of the enzyme denatured with methanol had two negative peaks, at 222 and 270 nm, and a positive peak at 236 nm. The changes in the fluorescence and ultraviolet difference spectra reflected the changes of the microenvironments of tryptophan and tyrosine residues of the enzyme. The CD spectrum changes of the enzyme show that the secondary structure of the enzyme also changed some. These results suggest that methanol is a non-competitive inhibitor and the conformational integrity of the enzyme is essential for its activity.

Acid Phosphatase↗