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C Figarella

Publications and source records attributed to C Figarella.

At least 91 records · Page 5Linked to original sources

Human serum pancreatic lipase and trypsin 1 in aging: enzymatic and immunoenzymatic assays.

Two major human pancreatic proteins, lipase and trypsin I, were measured in human sera from 35 elderly healthy adults and 51 young healthy adults. Lipase enzymatic activity was determined by a turbidimetric assay in the presence of colipase; lipase immunoreactive protein and trypsin immunoreactive protein were measured by using immunoenzymatic assays. Serum levels of the pancreatic enzymes were similar in young and elderly adults, with no significant differences between the groups for any of the assays. There was a close correlation between lipase enzyme activity and immunoreactivity in all participants, suggesting that the catalytic activity of lipase was not affected by aging. There were also significant correlations between the levels of immunoreactive lipase protein and immunoreactive trypsin protein, within and between the two groups, suggesting an age-independent relationship between these two pancreatic enzymes.

Adult↗

"In vivo" and "in vitro" inhibition of human pancreatic chymotrypsin A by serum inhibitors.

The interaction of human pancreatic chymotrypsin A with serum inhibitors was assessed by enzyme immunoassay, enzymatic activity and inhibitory capacity measurements and electrophoretic analyses. In normal serum, chymotrypsin A was detected in four forms: one form (Mr approximately equal to 25,000) which might be chymotrypsinogen A and three forms complexed to the main inhibitors present in serum, alpha 2-macroglobulin (alpha 2-M), alpha 1-proteinase inhibitor (alpha 1-PI) and alpha 1-antichymotrypsin (alpha 1-Achy). As chymotrypsin A remains to 90% active when bound to alpha 2-M, the chymotrypsin A/alpha 2-M complex was quantified by an enzymatic assay. The kinetic parameters of the interaction of chymotrypsin A with alpha 1-PI and alpha 1-Achy were determined. Using these data the partition of chymotrypsin A between the different inhibitors in serum was calculated. In acute pancreatitis, the chymotrypsin A plasma level follows the progression of the disease and in this case as well as in normal serum alpha 1-PI is the major antagonist of chymotrypsin A.

Blood Proteins↗

Protein X, a proteolysis product of human pancreatic juice. Immunological relationship with trypsinogen 1.

Protein X (PX) previously isolated from human pancreatic juice is an inactive protein of 14 kDa which has been shown to be a degradation product liberated by proteolysis of 19 kDa precursors. Polyclonal antibodies against P19 and PX were prepared in rabbits by injection of the two proteins purified by SDS polyacrylamide gel electrophoresis. These antibodies reacted with a form of trypsin 1 (DFP-trypsin 1) which was shown to be partly proteolysed. Immunological studies were performed with pancreatic juice proteins and partially purified trypsinogen 1 using antibodies directed against PX, P19 and trypsin 1. The results of immunoprecipitation and immunoadsorbent chromatography show that these different antisera recognized a protein of 25 kDa. Immunoblotting has permitted to characterize this protein as a trypsinogen 1-like molecule which would be a form of inert protein generated by uncontrolled trypsinogen activation.

Amino Acids↗

Assay of human pancreatic lipase in biological fluids using a non-competitive enzyme immunoassay.

A sandwich enzyme immunoassay has been developed for human pancreatic lipase using polystyrene balls coated with specific IgG as the first antibody and peroxidase-labelled IgG as the second antibody. The detection limit was 0.5 microgram/l. Good parallelism was observed with the curves obtained from standard lipase and lipase present in serum, pancreatic juice and duodenal contents, demonstrating that the assay may be used to measure the level of the protein in different biological fluids. Mean values of lipase in human sera were 12.3 +/- 6.8 micrograms/l in adults and 4.5 +/- 2.7 in newborns. In all cases a good correlation was found in serum between the catalytic activity and the enzyme immunoassay. Lipase is detectable in amniotic fluids at the 18th week of pregnancy but at a very low level (0.95 +/- 0.32 microgram/l). In pancreatic juices, lipase concentration was 14.6% of the total protein content. A study on cystic fibrosis patients showed a poor correlation between blood pancreatic lipase concentration and fat malabsorption underlying the difficulty in assessing pancreatic function by the measurement of serum pancreatic enzymes. The use of the lipase assay in duodenal contents would permit better assessment of pancreatic function in patients presenting a severe or borderline defect in fat digestion and absorption.

Amniotic Fluid↗

Human pancreatic chymotrypsinogen A: a non-competitive enzyme immunoassay, and molecular forms in serum and amniotic fluid.

A sandwich enzyme immunoassay has been developed for human pancreatic chymotrypsin(ogen) using polystyrene balls coated with specific IgG as the first antibody and peroxidase-labelled IgG as the second antibody. The detection limit was 0.5 microgram/l. A good parallelism was observed with the curves obtained from standard chymotrypsinogen A and chymotrypsin(ogen) present in pancreatic juice; however, a slight discrepancy in parallelism with chymotrypsin(ogen) present in serum and amniotic fluid was noticed. Chymotrypsinogen concentration in pancreatic juice was evaluated to represent 9% of total proteins. Mean values of chymotrypsin(ogen) in human sera were 24.6 +/- 8.3 micrograms/l in adults and 20.9 +/- 8.8 micrograms/l in newborns. In amniotic fluid at the 18th week of pregnancy the values were scattered (5-70 micrograms/l). The molecular forms of immunoreactive chymotrypsin(ogen) in normal serum and amniotic fluid have been investigated by gel filtration on Sephadex G-100. Two peaks of immunoreactive chymotrypsin(ogen) were observed in normal serum; the first peak elutes in a position consistent with a complex of chymotrypsin with serum inhibitor (Mr 76,000), and the second peak elutes with a molecular weight of approx. 25,000 corresponding to the elution position of free chymotrypsin(ogen). In normal amniotic fluid three peaks of immunoreactive material were present; the first and second peaks elute in the same position as in serum, and the third peak with a molecular weight of about 14,500 may represent a degraded form of chymotrypsin.

Adult↗

Physiologically elevated concentration of serum trypsin-like immunoreactivity in newborns. Comparison with lipase.

Comparative measurements on the levels of immunoreactive trypsin(ogen)-1 and lipase have been performed on newborn and adult sera. Values observed for immunoreactive trypsin(ogen)-1 with newborn sera are more dispersed and significantly higher (mean +/- SD, 31.9 +/- 12.9 micrograms/l) than the values obtained with adult sera (20.2 +/- 7.3 micrograms/l). The molecular size distribution of the immunoreactive trypsin-like material in newborns was studied by gel filtration. This material was eluted with a molecular weight of 25,000 which eliminates the possibility of an increased intestinal permeability of active trypsin which would be bound to serum protease inhibitors. In contrast to trypsin values, the mean serum lipase value at birth was significantly lower (7.0 +/- 3.2 micrograms/l) than the value observed for adults (26.9 +/- 8.2 micrograms/l). The possibility of an adaptation process in newborns is evoked.

Adult↗

Duodenal lactoferrin in patients with chronic pancreatitis and gastrointestinal diseases.

Lactoferrin (LF), chymotrypsin and lipase activity were measured in duodenal juice during pancreatic stimulation. Secretin (0.5 CU/kg/h) plus cerulein (75 ng/kg/h) were infused intravenously in 98 subjects: 33 patients without organic diseases (C), 40 patients affected by chronic pancreatitis (CP), and 25 patients with different gastrointestinal diseases (GID). LF was determined by means of a new noncompetitive immunoenzymatic assay with a sensitivity in the duodenal juice of 5 ng/ml. Duodenal LF concentrations were significantly higher in CP than in C or GID (p less than 0.001). LF was in a normal range in acute relapsing pancreatitis due to biliary stones or pancreas divisum. In the diagnosis of the chronic pancreatitis, LF/lipase ratios showed a specificity of 93% and a sensitivity of 95%. Our results show that LF immunoassay in duodenal juice is a sensitive and accurate assay to apply in pancreatic function tests involving duodenal content analysis.

Adult↗

Characterization and N-terminal sequence of a degradation product of 14,000 molecular weight isolated from human pancreatic juice.

Chromatography of human pancreatic juice has allowed the isolation of an inactive protein of 14,000 Mr (protein X) and the determination of its amino acid composition and N-terminal sequence. Protein X was found to be immunologically identical to the protein extracted from precipitates present in the pancreatic juices of patients with chronic calcifying pancreatitis and recently shown to be a degradation product of trypsinogen 1. The same chromatography performed in the presence of lima bean trypsin inhibitor has permitted the isolation of precursors of approximately congruent to 19,000 Mr which can be transformed into protein X "in vitro" by chymotrypsin hydrolysis. These results emphasize the easy activation of human pancreatic zymogens and the possible consequences due to proteolysis in pancreatic disease.

Amino Acid Sequence↗

Proteolysis of human trypsinogen 1. Pathogenic implication in chronic pancreatitis.

SDS electrophoresis on polyacrylamide gels of purified trypsinogen 1 has shown the occurrence of a proteolysis in some molecules during long storage at -20 degrees C. This proteolyzed trypsinogen gives a positive reaction with an antiserum directed against the precipitate protein, major protein of about 14 000 molecular weight extracted from precipitates present in the pancreatic juice of patients with chronic pancreatitis. The autoactivation of proteolyzed trypsinogen 1 liberates a polypeptide of 14 000 molecular weight which is immunologically identical to the precipitate protein. These results show that the major protein present in pancreatic precipitates (and pancreatic stones) of patients with chronic pancreatitis is a degradation product of trypsinogen 1 liberated by a proteolysis which necessarily requires a premature zymogen activation in the disease.

Chronic Disease↗

Immunohistochemical localization of intestinal phospholipase A2 in rat paneth cells.

Using the peroxidase-anti-peroxidase (PAP) technique with a specific rabbit anti-swine intestinal-phospholipase-A2 serum, the immunoreactivity of this phospholipase A2 was localized in rat-intestinal Paneth cells. The specific rabbit anti-swine intestinal-phospholipase-A2 serum did not stain the rat-pancreatic acinar cells which were stained by a specific rabbit anti-swine pancreatic-phospholipase-A2 serum. Specific rabbit anti-swine pancreatic-phospholipase-A2 serum did not stain rat-intestinal Paneth cells. Therefore, there is no cross-immunoreactivity between pancreatic and intestinal phospholipases.

Animals↗

Effect of lactoferrin on the growth of a human colon adenocarcinoma cell line--comparison with transferrin.

Lactoferrin was examined for its effect on the growth of a human colon adenocarcinoma cell line (HT 29) in culture and its action was compared to that produced by transferrin and two different iron solutions (ferrous sulfate and ferric chloride). When transferrin was replaced by either iron solutions the cell grew in proportion to the quantity added and the maximal effect obtained was identical to that produced by transferrin alone. When transferrin was replaced by lactoferrin the cells were unable to proliferate for a long time. However, in the presence of low-concentration iron solutions, lactoferrin stimulated the cell growth, and the effect was more pronounced with the ferric chloride solution.

Adenocarcinoma↗

Detection of the cystic fibrosis protein by isoelectric focusing of serum and plasma.

We used the isoelectric focusing method developed by Wilson to analyze serum from individuals homozygous or heterozygous for cystic fibrosis. The presence of cystic fibrosis protein (CFP) was found in 37 out of 52 homozygous and 24 out of 34 heterozygous patients, which leads to a frequency of 71% for both families. Five out of 24 controls were found positive. The same study, performed on 26 plasma samples collected from the same patients, demonstrated that the detection of CFP is possible in plasma as well as in serum. Our results confirm the presence of a protein "marker" of CF in serum, but also underlines the lack of sensitivity of the isoelectric focusing technique to be used for diagnosis.

Blood Proteins↗

[Plasma lactoferrin and the blood count of polynuclear neutrophils].

Plasmatic lactoferrin measure (LF) by immuno-enzymatic technique combined with neutrophil blood count (PN) on 100 subjects (controls and patients) allows us to show a LF increase proportional to circulating blood neutrophils. In neutropenia, plasmatic lactoferrin measure seems able to divide the central causes from the peripheric ones. Regarding the granulocytosis, LF levels are clearly higher in myeloproliferative diseases than in other causes. Lactoferrin could therefore represent an index of total circulating neutrophil pool but also seems to reflect the granulocyte activation.

Adult↗

Non-competitive enzyme immunoassay of human trypsin 1.

A sandwich enzyme immunoassay was developed for human pancreatic trypsin 1 using polystyrene balls coated with specific IgG as the first antibody and peroxidase-labeled IgG as the second antibody. The entire assay takes 6 h and the detection limit is 0.5 microgram/l. The assay can be performed on sera samples or on discs carrying dried blood spots. Good agreement was found with a radioimmunoassay kit. This simple assay could be widely applied to confirm the elevated immunoreactive serum trypsin described in newborn children with cystic fibrosis.

Adult↗

A non competitive enzyme immunoassay of human lactoferrin in biological fluids.

A sandwich enzyme immunoassay was developed for human lactoferrin using polystyrene balls coated with specific IgG fraction as the first antibody and peroxidase labelled IgG fraction as the second antibody. The detection limit was 1 microgram/l. A good parallelism was observed with the curves obtained from standard lactoferrin (purified from mammary gland), plasma lactoferrin (mainly derived from granulocytes), and pancreatic lactoferrin demonstrating that the assay may be used to measure the level of the protein in different biological materials. The simplicity and the sensitivity of this assay may permit the follow-up of patients with chronic calcifying pancreatitis (in which an increase of pancreatic lactoferrin has already been demonstrated) and a study of the protein in various circumstances leading to a better understanding of its biological role.

Adult↗