Effect of procainhydrochloride on phospholipase A2 catalytic activity in sodium taurocholate-induced acute experimental pancreatitis in rats.

BACKGROUND: In human acute pancreatitis (AP) the local anaesthetic procainhydrochloride (procain-HCl) is given intravenously for pain treatment. Procain has been shown to inhibit catalytic activity of pancreatic (group I) phospholipase A2 (PLA2) and non-pancreatic (group II) PLA2. Both enzymes are important mediators for the local and systemic inflammatory process in AP. To determine the effect of procain, we examined serum and tissue levels of both types of PLA2 activity in the experimental rodent taurocholate model of AP. METHODS: In 60 rats, severe pancreatitis was induced by taurocholate. Forty rats were treated with procain-HCl intravenously at a dosage of 2 mg/kg body weight/h either at or 1 h after induction of pancreatitis. Twenty rats served as controls. We measured catalytic activities of group I and group II PLA2 in serum and tissue samples of lung and pancreas. RESULTS: Serum group II PLA2 catalytic activity was significantly reduced 3 and 6 h after AP induction in rats treated with procain-HCl (p < 0.001) in both treatment groups. In pancreatic and lung tissue, group II PLA2 catalytic activity was significantly reduced compared with normal values (p < 0.001). CONCLUSION: Procain-HCl given intravenously either at or 1 h after induction of necrotizing pancreatitis significantly inhibits group II PLA2 catalytic activity in serum and tissues.

Value of blood tests including serum group IIA phospholipase A2 and bactericidal/permeability-increasing protein in Crohn's disease.

OBJECTIVE: Determination of the activity of Crohn's disease at a defined time-point is a challenging task since only endoscopy guidelines are given and secondary clinical findings, subjective symptoms and non-specific laboratory tests have therefore to be relied on. The purpose of the current study was to investigate the ability of blood tests to differentiate patient groups with different clinical disease activity and different clinical outcomes during follow-up in Crohn's disease. MATERIAL AND METHODS: During a visit to hospital, 73 outpatients with Crohn's disease were examined, a clinical score was calculated and blood samples were collected for 22 laboratory tests. The patients were also grouped according to clinical outcome during a 6-year follow-up. RESULTS: Serum group IIA phospholipase A2 and alpha-1-antitrypsin values were outside the reference interval more frequently (62% and 42%, respectively) than the other tests in active Crohn's disease. Only weak correlations were found between the clinical score and the test values, and the best correlation was found with serum lysozyme (r = 0.40). In a logistic regression model, the best prediction of disease activity at entry to the study was reached with a model including serum orosomucoid and serum lysozyme and the best prediction of clinical outcome during follow-up was reached using a model including serum albumin. CONCLUSIONS: Serum group IIA phospholipase A2 appeared to be the most sensitive marker of inflammation in Crohn's disease among the 22 blood tests compared. No reliable predictions of disease activity at the time of blood sampling or clinical outcome later during follow-up could be made from the blood tests studied.

Bactericidal/permeability increasing protein and proinflammatory cytokines in synovial fluid of psoriatic arthritis.

OBJECTIVE: Bactericidal/permeability increasing protein (BPI) is a leukocyte product exerting antibacterial activity. Its production may be stimulated by cytokines, mainly Tumor Necrosis Factor (TNF) alpha. We studied BPI in the synovial fluid (SF) of psoriatic arthritis (PsA), a disease suspected to be influenced by infectious agents. METHODS: The levels of BPI and various indices of SF inflammation, including cytokines and its receptors, were determined in the SF of 18 patients with PsA and compared with those of 12 patients with rheumatoid arthritis (RA) and 9 with osteoarthritis (OA). RESULTS: The lowest SF levels of BPI were found in PsA (145.3 +/- 97.3 ng/ml), significantly lower than in RA (307.7 +/- 42.8 ng/ml, p = 0.0001) and similar to those in OA (151.1 +/- 52.4 ng/ml). Furthermore, only in PsA, and not in the RA and OA subgroups, correlations were observed between BPI and the indices considered, including TNF alpha (r = 0.746, p = 0.0004). CONCLUSION: Due to its relationship with local inflammation, SF BPI may play a role in the pathogenesis of arthropathies, in particular PsA.

Bactericidal/permeability-increasing protein (BPI) in sepsis correlates with the severity of sepsis and the outcome.

OBJECTIVE: To compare the prognostic significance of bactericidal/permeability-increasing protein (BPI), group II phospholipase A2 (PLA2-II), C-reactive protein (CRP), tumour necrosis factor-alpha (TNF), interleukin-8 (IL-8) and interferon-gamma (IFN) in terms of predicting severity of sepsis and outcome. DESIGN: A prospective study. SETTING: Medical intensive care unit (ICU) of a university hospital. PATIENTS: Thirty-four patients with severe sepsis requiring ICU treatment. MEASUREMENTS AND RESULTS: The levels of BPI, PLA2-II, CRP, TNF, IL-8 and IFN were measured in these 34 patients. High levels of BPI were associated particularly with Gram-negative sepsis. BPI and BPI/neutrophil ratios correlated positively with PLA2-II, CRP, TNF and IL-8 and negatively with blood pressure. At 24 h, BPI/neutrophil ratios, IL-8 and Simplified Acute Physiology Scores II (SAPS II) scores were higher in non-survivors than in survivors. No such associations were noted in the levels of CRP, PLA2-II, TNF or IFN. The areas under the curve (AUC(ROC)s) of SAPS II scores and IL-8 were higher than AUC(ROC) of BPI/neutrophil ratio. CONCLUSION: The BPI and BPI/neutrophil ratios may serve as adjunctive tools to illustrate the severity of sepsis. However, their predictive power for sepsis-related death was not comparable to that of SAPS II scores and IL-8.

Human meconium has high phospholipase A2 activity and induces cellular injury and apoptosis in piglet lungs.

Aspiration of meconium produces an inflammatory reaction resulting in necrotic changes in lung tissue. To further investigate the mechanisms of the meconium-induced early pulmonary injury, twenty 10-12-d-old piglets were studied for lung tissue ultrastructural and apoptotic changes and phospholipase A2 activity. Twelve piglets received an intratracheal bolus (3 mL/kg) of a 20-mg/mL (thin, n = 6) or 65-mg/mL (thick, n = 6) mixture of human meconium, and control piglets (n = 5) received the same amount of intratracheal saline. Three ventilated piglets with no aspiration were also studied. Pulmonary hemodynamics and systemic oxygenation were followed for 6 h after meconium or saline insufflation. In the control groups, the pulmonary tissue showed open alveolar spaces and intact vascular walls, whereas meconium administration resulted in severe pneumonitis, with alveolar spaces filled with inflammatory exudate. Meconium instillation additionally resulted in edematous changes in the vascular walls and alveolar epithelium, whereas type II pneumocytes were intact. The amount of apoptotic cells was increased, especially in the respiratory epithelium, and the catalytic activity of phospholipase A2 in lung tissue samples was significantly elevated after thick meconium instillation. This activity rise proved to be mainly because of human group I phospholipase A2, introduced by meconium. Our data thus show that aspiration of meconium leads to severe lung tissue inflammation with early ultrastructural changes in the pulmonary alveolar walls and is associated with apoptotic cell death in the epithelium, already during the first hours after the insult. These results further suggest that high phospholipase A2 activity, mainly introduced into the lungs within the meconium, may have an important role in the initiation of these alterations in neonatal lungs.

Extracellular phospholipases A2 in relation to systemic inflammatory response syndrome (SIRS) and systemic complications in severe acute pancreatitis.

The pathophysiology of severe acute pancreatitis (AP) resembles other conditions with systemic inflammatory response syndrome (SIRS) such as sepsis predisposing to remote organ failure. Because extracellular phospholipases A2 (PLA2) have been implicated in AP, their serum concentrations were analyzed with respect to SIRS and systemic complications in patients with severe AP. The serum samples were collected daily for 12 days in 57 patients with severe AP. SIRS, early organ complications, local complications, and outcome of AP were recorded. Time-resolved fluoroimmunoassays were used for group I and group II PLA2 measurements. Thirty-nine (68.4%) patients fulfilled the criteria of SIRS within 12 days from admission. Pancreatic necrosis was detected in 43 (75.4%) patients. Infected necrosis was found preoperatively or at operation in five (8.8%) patients. Twenty-six (45.6%) and eight (14.0%) patients had respiratory or renal failure, respectively. Seven (12.3%) patients died of their disease. All patients with systemic complications fulfilled the criteria of SIRS. The increasing number of positive SIRS criteria was associated with increased frequency of systemic complications. Pancreatic necrosis was not significantly associated with SIRS. The serum concentration of group II PLA2 was significantly higher in patients with SIRS (p < 0.05) compared with patients without from day 7 onward. The concentration of group II PLA2 increased (p < 0.01) in patients with SIRS but decreased in patients without. The serum concentration of group II PLA2 did not differ significantly with respect to systemic complications. The concentration of group I PLA2 decreased (p < 0.05) similarly in patients with and without SIRS or systemic complications during follow-up, respectively. Early systemic complications of severe AP are associated with SIRS with increasing frequency as the number of positive SIRS criteria increases. Group II PLA2 but not group I PLA2 may have pathophysiologic importance in severe AP-associated SIRS. Increasing serum concentration of group II PLA2 seems to reflect the ongoing systemic inflammation in severe AP-associated SIRS.

Elevated group II phospholipase A2 mass concentration in serum and colonic mucosa in Crohn's disease.

Group II phospholipase A2 has been proposed to play an important role in the pathophysiology of inflammatory bowel diseases. This enzyme has also been linked to host defence mechanisms against bacteria. The current study aimed at measuring the mass concentrations of group II phospholipase A2 in serum and colonic mucosa of patients with Crohn's disease of different severity and of appropriate control patients without any inflammatory disease. The activity of the disease was determined by clinical factors (the simple index score) and endoscopic and histological scoring. The mass concentration of group II phospholipase A2 was measured by a time-resolved fluoroimmunoassay. The mass concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher both in patients with active and inactive Crohn's disease when compared with controls. There was statistically significant difference in the mass concentration of group II phospholipase A2 in colonic mucosa but not in serum between inactive and active Crohn's disease. The current results indicate that the mass concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with Crohn's disease and that the latter is associated with the degree of the inflammatory activity in the intestinal wall. These results support the idea that group II phospholipase A2 is involved in the local and generalised pathological processes of Crohn's disease.

Inorganic pyrophosphatase-labelled enzyme immunoassay for beta 2-microglobulin.

beta 2-Microglobulin was purified from human peritoneal dialysate by ultrafiltration, gel chromatography and DEAE-high performance chromatography. Anti-beta 2-monoclonal antibodies were developed in mice and a pair of the antibodies was utilized to develop an enzyme-linked immunosorbent assay (ELISA) kit for the analyte with utilizing a new enzyme label, inorganic pyrophosphatase (EC 3.6.1.1). The sensitivity of the assay was 0.6 microgram/l (3 x SD) and the assay was linear up to absorbance values of around 2.0. No hook effect occurred in any putative concentrations of beta 2-microglobulin in serum. The precision of the assay of one run varied within 5-7% CV and the interassay precision was 2.8-8.6% CV, while the recovery was 99.2 +/- 6.0%. Excellent correlation occurred against an established radioimmunoassay method. All the used reagents were storable for a minimum of 1 year at +4 degrees C. It was decided that inorganic pyrophosphatase is a label of choice for ELISA.

Group II phospholipase A2 in nasal fluid, mucosa and paranasal sinuses.

The aim of this study was to determine the type of phospholipase A2 (PLA2) in nasal fluid and to demonstrate its cellular origin. The concentration of group II PLA2 was high (591.5 micrograms/l) in nasal fluid compared with serum level (10.8 micrograms/l) and the fluid of paranasal sinuses (10.6 micrograms/l). Methacholine stimulated nasal fluid contained only small amounts (19.1 micrograms/l) of group II PLA2 when the flow of tear fluid through the nasolacrimal duct was obstructed. Occasional glands secreting group II PLA2 were found in nasal and paranasal mucosa by immunohistochemistry. Lysozyme was found in the majority of mucosal glands. It was concluded that nasal and paranasal mucosal glands contain group II PLA2. In nasal fluid, however, PLA2 is mainly derived from tear fluid.

Lipopolysaccharide induced apoptosis of rat pancreatic acinar cells.

BACKGROUND: Bacterial lipopolysaccharide (LPS) has been proposed to participate in the pathogenesis of pancreatic inflammatory disease. AIMS: This study investigated the role of endotoxaemia in the pathogenesis of pancreatic acinar cell injury. METHODS: Sixty eight male Spraque-Dawley rats were used in the study. Escherichia coli LPS (5 mg/kg) was injected into the peritoneal cavity of the rats. The concentration of pancreatic phospholipase A2 (PLA2) in plasma was measured and pancreatic tissue examined by histology, in situ detection of free DNA 3'-ends, and electrophoretic DNA analysis. RESULTS: The concentration of pancreatic PLA2 increased in plasma and the catalytic activity of PLA2 increased in pancreatic tissue after an LPS injection. Apoptosis in pancreatic acinar cells and fragmentation of DNA typical of apoptosis in pancreatic tissue was seen 24 hours after an LPS injection. Pancreatic acinar atrophy was seen 72 hours after the LPS injection. CONCLUSIONS: These data show that LPS causes release of pancreatic PLA2 into blood plasma, activation of PLA2 in pancreatic tissue, and apoptosis of acinar cells.

Time-resolved fluoroimmunoassay for bactericidal/permeability-increasing protein.

Bactericidal/permeability-increasing protein (BPI) is a cationic antimicrobial protein produced by polymorphonuclear leukocytes, that specifically interacts with and kills Gram-negative bacteria. BPl competes with lipopolysaccharide-binding protein (LBP) secreted by liver cells into blood plasma for binding to lipopolysaccharide (LPS) and thus reduces the proinflammatory effects of LPS. We have developed a time-resolved fluoroimmunoassay for BPI and measured the concentration of BPI in human serum and plasma samples. The assay is based on a rabbit antibody against recombinant BPI. This antibody specifically adheres to polymorphonuclear leukocytes in immunostained human tissues. The difference in the serum concentration of BPI between unselected hospitalized patients with and without an infection was statistically significant. The mean concentration of BPI in serum samples was 28.3 mug/l (range 1.64-132, S.D. 26.8, n = 83). In contrast, there was no difference between the two groups in the BPI levels in plasma samples. For all individuals tested, BPI levels were consistently higher in plasma samples compared to the matched serum samples. The mean concentration of BPI in plasma samples was 52.3 mug/l (range 0.9-403, S.D. 60.6, n = 90). There was a positive correlation between the concentration of BPI and the white blood cell count as well as between the BPI concentration and C-reactive protein (CRP) in serum samples. In conclusion, the present study demonstrates that BPI can be quantified reliably by time-resolved fluoroimmunoassay in human serum samples.

Phospholipase A2 in sodium taurocholate-induced experimental hemorrhagic pancreatitis in the rat.

We investigated the concentration of immunoreactive pancreatic phospholipase A2 (pan-PLA2) and the catalytic activity of phospholipase A2 (CA-PLA2) in plasma, peritoneal fluid, and pancreas of rats in which acute hemorrhagic pancreatitis was induced by an intraductal injection of sodium taurocholate. The contribution of pancreas to the CA-PLA2 in plasma was studied by removing pancreatic PLA2 by absorbing plasma samples with a polyclonal antibody raised in a rabbit against rat pancreatic PLA2. Sodium taurocholate injected into the pancreatic duct produced hemorrhagic pancreatitis with necrosis and inflammatory cell invasion within 8 hr. Saline injection caused edematous pancreatitis, but sham operation did not alter pancreatic morphology from normal. The concentration of pan-PLA2 increased rapidly in plasma in all animals, but significantly more in sodium taurocholate-injected animals than in saline-injected or sham-operated animals. The level of CA-PLA2 in plasma increased in sodium taurocholate-injected animals only. There was no correlation between pan-PLA2 and CA-PLA2 values in plasma in sodium taurocholate-injected animals. The CA-PLA2 was marginally increased in pancreatic tissue of sodium taurocholate-injected animals compared to that of saline-injected and sham-operated animals at 8 hr. Treatment by the anti-pan-PLA2 antibody effectively removed pan-PLA2 from plasma and peritoneal fluid samples in sodium taurocholate-injected animals. The level of CA-PLA2 in plasma was similar before and after antibody treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Secretion of group 2 phospholipase A2 by lacrimal glands.

PURPOSE: Tears are known to have antimicrobial properties. The authors investigated the presence of the antibacterial enzyme phospholipase A2 (PLA2) in tears and lacrimal glands. METHODS: The catalytic activity of PLA2 and the amount of pancreatic group 1 PLA2 and nonpancreatic group 2 PLA2 were measured in homogenates of eight human lacrimal glands from autopsied subjects and in tears from four healthy volunteers. The localization of PLA2s in lacrimal gland sections was studied by immunohistochemistry. Skeletal muscle was used as a control. RESULTS: The catalytic activity of PLA2 was significantly higher in lacrimal glands than in skeletal muscle. Immunochemical analysis showed significantly higher amounts of group 2 PLA2 in lacrimal gland than in skeletal muscle homogenates. Group 1 PLA2 was present in trace amounts only. The concentration of group 2 PLA2 in tears was high (1451.3 micrograms/l) compared to that in the serum of healthy individuals (3.7 micrograms/l). By immunohistochemistry, a granular reaction of group 2 PLA2 was localized in the glandular cells of lacrimal glands. The apical cytoplasm of many duct cells also was labeled. CONCLUSIONS: The lacrimal glands secreted nonpancreatic group 2 PLA2, which most likely acts as an antiinfectious factor in tears.

Group I and group II phospholipases A2 in serum in uraemia.

Time-resolved fluoroimmunoassays were used for the detection of pancreatic group I and synovial-type group II phospholipases A2 in sera of patients suffering from chronic renal failure before and after haemodialysis. The concentration of group I phospholipase A2 was ten-fold higher in sera of uraemic patients than in healthy controls. There was no significant difference in the concentrations of group I phospholipase A2 in serum before and after haemodialysis. The concentration of group II phospholipase A2 was only marginally increased in sera of uraemic patients, compared with healthy controls. There was no significant difference in the concentrations of group II phospholipase A2 before and after haemodialysis. The results indicate that the metabolism of group I phospholipase A2 differs from that of group II phospholipase A2 in chronic renal failure.

Pyrophosphatase-based enzyme-linked immunosorbent assay of total IgE in serum.

Human IgE was purified to near homogeneity by a two-step procedure consisting of immunoaffinity chromatography and high-performance liquid chromatography. Mouse hybridoma cell lines secreting antibodies against IgE were generated. Monoclonal and polyclonal antibodies were used to develop a "sandwich"-type ELISA for determining total IgE in human serum. Inorganic pyrophosphatase (EC 3.6.1.1), an enzyme having a high turnover number, was used as the label. The mean analytical recovery of our ELISA was 95.2% and the results showed good linear correlation with an established RIA of IgE. We found pyrophosphatase to be a good alternative label for use in immunoassays.