Purification and Some Properties of Membrane-Associated
Phospholipase A(2) of Human Spleen

Nakaguchi, Kazunori; Nishijima, Junichi; Ogawa, Michio; Mori, Takesada; Tojo, Hiromasa; Yamano, Toshìo; Okamoto, Mitsuhiro

doi:10.1159/000469312

Cited by 19 publications

(9 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In 1983, Eskola et al [8] and we ourselves [9] independently developed a specific im munoassay for human pancreatic PLA2 (P-PLA2), and later we showed that the ra dioimmunoassay (RIA) for human P-PLA2 did not react with PLA2 from the human spleen [10]. Uhl et al [11] have reported an increase in serum catalytic PLA2 activity in patients with multiple injuries.…”

Section: Human M-pla2mentioning

confidence: 98%

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Matsuda

Ogawa²,

Saito³

et al. 1991

Enzyme

Self Cite

View full text Add to dashboard Cite

A radioimmunoassay (RIA) for the determination of human group-II phospholipase A(2) (M-PLA(2)) has been developed. M-PLA(2) was purified from human spleen. Monoclonal antibody (IgG) was prepared by fusion of splenic cells from immunized mice with M-PLA(2) and the mouse myeloma cell line NS-1. The RIA was carried out by a single antibody method. The assay is sensitive (0.78 μg/1), reproducible and specific. In healthy individuals, the serum M-PLA2 concentration ranges from 1.4 to 4.2 μg/l, the average being 2.2 ± 0.1 μg/1 (mean ± SE). Using the RIA, we found increased serum M-PLA(2) in patients with various infections and malignant tumors. We also showed the postoperative transient elevation of serum M-PLA(2) in cases without any infectious complications. The elevation was independent of the surgical procedure or site. The maximum serum M-PLA(2) level was seen on the 2nd to 4th postoperative day. In these patients, the serum M-PLA(2) and C-reactive protein levels were significantly correlated. The present study indicated that serum M-PLA(2) is an acute phase reactant.

show abstract

Section: Human M-pla2mentioning

confidence: 98%

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Matsuda

Ogawa²,

Saito³

et al. 1991

Enzyme

Self Cite

View full text Add to dashboard Cite

show abstract

“…Until recently, two genetically distinct isoenzymes, exocrine PLA2 (secreted in pancreatic juice) and intracellular PLA2 (contained in the cytosol and membrane-associated fraction), have been recognised in humans (Vadas & Pruzanski, 1986;Nakaguchi et al, 1986). In the membrane fraction of human spleen cells the existence of a PLA2, which does not react with anti-human P-PLA2 antibody, has been demonstrated (Nakaguchi et al, 1986). Further purification and subsequent sequencing of this enzyme revealed that it belongs to the Group-I1 PLA2 (Kanda et al, 1989).…”

mentioning

confidence: 99%

“…In addition, a calcium-dependent PLA2 is thought to be one of the most important enzymes regulating the release of arachidonic acid from membrane phospholipids (Lands, 1968; Van den Bosh, 1980). Until recently, two genetically distinct isoenzymes, exocrine PLA2 (secreted in pancreatic juice) and intracellular PLA2 (contained in the cytosol and membrane-associated fraction), have been recognised in humans (Vadas & Pruzanski, 1986;Nakaguchi et al, 1986). In the membrane fraction of human spleen cells the existence of a PLA2, which does not react with anti-human P-PLA2 antibody, has been demonstrated (Nakaguchi et al, 1986).…”

mentioning

confidence: 99%

Expression of group-II phospholipase A2 in malignant and non-malignant human gastric mucosa

Murata

Egami²,

Kiyohara³

et al. 1993

Br J Cancer

View full text Add to dashboard Cite

Summary The expression of Group-TI phospholipase A2 (M-PLA2) was analysed immunohistochemically in malignant, non-malignant (including atrophic, hyperplastic, pseudopyloric metaplastic and intestinal metaplastic) and normal human gastric mucosae. M-PLA2 was consistently detected in the stem cell lineage, pseudopyloric metaplasia and the generative cells of hyperplastic foveolar epithelium and intestinal metaplasia (IM). In IM, the appearance of Phospholipase A2 (PLA2) catalyses the specific hydrolysis of a fatty acyl ester bond at the sn-2 position of glycerophospholipids. In addition, a calcium-dependent PLA2 is thought to be one of the most important enzymes regulating the release of arachidonic acid from membrane phospholipids (Lands, 1968; Van den Bosh, 1980). Until recently, two genetically distinct isoenzymes, exocrine PLA2 (secreted in pancreatic juice) and intracellular PLA2 (contained in the cytosol and membrane-associated fraction), have been recognised in humans (Vadas & Pruzanski, 1986;Nakaguchi et al., 1986). In the membrane fraction of human spleen cells the existence of a PLA2, which does not react with anti-human P-PLA2 antibody, has been demonstrated (Nakaguchi et al., 1986). Further purification and subsequent sequencing of this enzyme revealed that it belongs to the Group-I1 PLA2 (Kanda et al., 1989). Group-II PLA2 has been thought to play an important regulatory role in several metabolic pathways (Nakano et al., 1990a;Nakano et al., 1990b). And recently, the distribution of this Group-II-PLA2 in human organs has been published (Kiyohara et al., 1992).The product of this enzyme's action, free arachidonate (which serves as a substrate for the cyclo-oxygenase route and lipoxygenase route) (Van den Bosh, 1980) is the first and rate-limiting precursor in the biosynthes of prostaglandins (PG), leukotriene and HETE (Lands, 1979; Van den Bosh, 1980). Among these products, PG is abundant in gastrointestinal mucosa (Robert et al., 1979), and especially PGE2, has potent cytoprotective effects, e.g. inhibition of gastric secretion, prevention of ulcer formation, and acceleration of the healing of mucosal damage (Robert et al., 1979;Wilson et al., 1971;Robert et al., 1976). Nevertheless, the biological significance and function of PLA2 in the human stomach is still unknown. In the rat gastric mucosa, PLA2 which is structurally identical to the rat pancreatic type PLA2 (P-PLA2, Group-I PLA2) (Tojo et al., 1988;Okamoto et al., 1985) was immunocytochemically detected in chief cells (Tatsumi et al., 1990). Knowledge of the distribution of this enzyme in human gastric mucosa might provide useful insight into the function of PLA2 in gastric mucosa.In this study, the immunohistochemical expression of M-PLA2 was examined by using a monoclonal antibody (MoAb) against the recently described human splenic Group-II PLA2 (M-PLA2) in a variety of human gastric mucosae, such as normal, atrophic, hyperplastic, pseudopyloric metaplastic and intestinal metaplastic mucosae, as well as cancerous lesions. Moreover, the po...

show abstract

“…PLA, from other tissues is inhibited by guanidinobenzoates and amidino derivatives (Hesse and Lankisch, 1984;Nakaguchi et al, 1986;Pepinsky et al, 1986) and indomethacin (Drummond and Olds-Clarke, 1986;Bonney et al, 1988). These agents are generally regarded as acrosin and cyclooxygenase inhibitors.…”

Section: Introductionmentioning

confidence: 99%

Characterization and inhibitor sensitivity of human sperm phospholipase A₂: Evidence against pivotal involvement of phospholipase A₂ in the acrosome reaction

Anderson

Johnson

Bielfeld

et al. 1990

Molecular Reproduction Devel

View full text Add to dashboard Cite

The kinetic properties and inhibitor sensitivity of human sperm phospholipase A2 (PLA2; EC 3.1.1.4) were studied. Phospholipase activity was isolated from human spermatozoa by acid extraction. Hydrolysis of dipalmitoyl phosphatidylcholine was specific to the sn-2 position. Activity was sensitive to product inhibition (60% inhibition by 0.1 mM lysophosphatidylcholine). The effects of Ca2+ and sodium deoxycholate on enzyme activity were biphasic; maximal activities were observed at 0.5 mM concentration of each agent. PLA2 was stimulated (135%) by 3% dimethylsulfoxide and was inhibited by elevated ionic strength (approximately 70% inhibition with either 0.2 M NaCl or 0.2 M KCl). Two molecular forms of PLA2 were kinetically distinguishable, one with an apparent Michaelis constant and maximal reaction velocity of 3.0 microM and 0.64 mlU/mg protein and the other with respective constants of 630 microM and 32.0 mlU/mg protein. Both forms of the enzyme were Ca2+ dependent and heat stable; however, the low-Km activity was less resistant to 60 degrees C preincubation at pH 7.5 (28% inactivation of low-Km activity after 45 min, as compared to no effect on high-Km activity). Quinacrine was a noncompetitive PLA2 inhibitor with Kis for low- and high-Km activities of 0.42 mM and 0.49 mM, respectively. Trifluoperazine (calmodulin antagonist) inhibited the high-Km activity noncompetitively (Ki = 87 microM) and the low-Km activity by a mechanism consistent with the removal of a nonessential activator. Dissociation and rate constants for inactivation of low- and high-Km activities by p-bromophenacyl bromide were 0.28 mM and 0.032 min-1, and 0.73 mM and 0.066 min-1, respectively. PLA2 was inhibited by p-nitrophenyl-p'-guanidinobenzoate, at higher concentrations (10(-4)-10(-3) M) than required to inhibit trypsinlike proteinases; p-aminobenzamidine, another potent trypsin/acrosin inhibitor, stimulated (approximately 40%) PLA2 at concentrations from 2-5 mM but inhibited PLA2 (40-50%) at a concentration of 10 mM. MnCl2 (5mM) inhibited low- and high-Km PLA2 activities by 77% and 76%, respectively. Quinacrine (0.4 mM), trifluoperazine (20 microM), p-bromophenacyl bromide (20 microM), and MnCl2 (5 mM) were tested as inhibitors of the ionophore A23187-induced human acrosome reaction. Inhibition was noted only with quinacrine (32%) and MnCl2 (93%). The effect of MnCl2 was restricted to an interaction with A23187, rather than with PLA2; p-Bromophenacyl bromide inhibited (P less than 0.05) PLA2 (29%) when added to intact spermatozoa but had no effect on the acrosome reaction. PLA2 inhibition was poorly correlated with the acrosome reaction.(ABSTRACT TRUNCATED AT 400 WORDS)

show abstract

Purification and Some Properties of Membrane-Associated Phospholipase A(2) of Human Spleen

Cited by 19 publications

References 29 publications

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Expression of group-II phospholipase A2 in malignant and non-malignant human gastric mucosa

Characterization and inhibitor sensitivity of human sperm phospholipase A₂: Evidence against pivotal involvement of phospholipase A₂ in the acrosome reaction

Contact Info

Product

Resources

About

Purification and Some Properties of Membrane-Associated Phospholipase A(2) of Human Spleen

Cited by 19 publications

References 29 publications

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Development of a Radioimmunoassay for Human Group-II Phospholipase A2 and Demonstration of Postoperative Elevation

Expression of group-II phospholipase A2 in malignant and non-malignant human gastric mucosa

Characterization and inhibitor sensitivity of human sperm phospholipase A2: Evidence against pivotal involvement of phospholipase A2 in the acrosome reaction

Contact Info

Product

Resources

About

Characterization and inhibitor sensitivity of human sperm phospholipase A₂: Evidence against pivotal involvement of phospholipase A₂ in the acrosome reaction