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Biomedical subjects

K Ohlsson

Publications and source records attributed to K Ohlsson.

At least 91 records · Page 5Linked to original sources

Quantification of pancreatic secretory trypsin inhibitor in colonic carcinoma and normal adjacent colonic mucosa.

AIMS: To measure the content of immunoreactive human pancreatic secretory trypsin inhibitor (irPSTI) in colonic carcinoma and adjacent normal colonic mucosa. METHODS: From a stable hybridoma cell line producing monoclonal antibodies specific for human PSTI, a specific enzyme linked immunosorbent assay (ELISA) for human PSTI was developed. In a precipitation assay system these antibodies bound human PSTI in a dose-dependent manner. The specimens were obtained from resectional surgery. RESULTS: The content of irPSTI was 19.9 micrograms/g protein (0.55 micrograms/g tissue wet weight) in colonic carcinoma. In adjacent normal colonic mucosa 43.6 micrograms/g protein (1.12 micrograms/g tissue wet weight) was shown. CONCLUSIONS: The enzymatic degradation of surrounding tissue necessary for tumour cell invasion could be facilitated by this relative deficit of the inhibitor in infiltrative carcinoma.

Antibodies, Monoclonal↗

Stimulation of human polymorphonuclear leukocytes by recombinant human interleukin-1 beta.

Leukocyte activation is a property of systemic infection. Animal experiments indicate interleukin-1 (IL-1) as a possible modulator, while contradictory results have been reported from in-vitro stimulation of isolated leukocytes. The purpose of the present study was to investigate the activation of isolated polymorphonuclear (PMN) leukocytes in vitro by preparations of recombinant human IL-1 beta and IL-1 receptor antagonist, which in earlier studies could elicit and abrogate, respectively, a sepsis-like syndrome in rabbits. They have also been shown to influence acute phase protein synthesis in mice and rats, and release of leukocyte cathepsin G in vivo. It was found that recombinant human IL-1 beta elicited a dose-dependent luminol-enhanced chemiluminescence response in isolated human PMN leukocytes in the dose range 8.8 x 10(-11)-8.8 x 10(-8) M. The effect could be blocked by prior treatment with the IL-1 receptor antagonist, indicating a direct effect on the specific IL-1 receptor. Preincubation by IL-1 beta enhanced the effect of a secondary challenge with phorbol 12-myristate 13-acetate or formyl-Met-Leu-Phe by 30-40%. The priming effect of rhIL-1 beta could also be blocked by the specific receptor antagonist. In this study, incubation of PMN leukocytes with rhIL-1 beta failed to induce degranulation of both azurophil (neutrophil proteinase 4/proteinase 3) and specific (lactoferrin) granules. rhIL-1 beta has been shown to induce degranulation in vivo, which is thus indicated as an indirect effect. We conclude that IL-1 beta is a direct and specific, but probably weak stimulator of the PMN leukocyte.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Degranulation↗

Release of neutrophil proteinase 4(3) and leukocyte elastase during phagocytosis and their interaction with proteinase inhibitors.

Neutrophil proteinase 4 (NP4) is a major neutral proteinase of the human polymorphonuclear (PMN) leukocyte, which is present in amounts similar to leukocyte elastase. NP4(3) is a potent, non-specific proteinase, which may degrade structural and soluble proteins in the tissues and body fluids, and it has been implicated as an important pathogenetic factor in lung emphysema. We have studied the release of elastase and NP4(3) in an in vitro model of phagocytosis. alpha 1-proteinase inhibitor (alpha 1-PI) is the major plasma inhibitor of both leukocyte elastase and NP4(3), but alpha 1-PI bound leukocyte elastase more readily than NP4(3). The basic conditions were designed so that some proteolytic activity was present in the medium. Addition of increasing amounts of Secretory leukocyte protease inhibitor (SLPI) to the incubation mixtures resulted in binding of leukocyte elastase to this inhibitor and extinction of free proteolytic activity against both natural and synthetic substrates. The progressive binding of leukocyte elastase to SLPI instead of alpha 1-PI was paralleled by an increasing binding of NP4(3) to alpha 1-PI. SLPI is a potent inhibitor of leukocyte elastase and cathepsin G, and although it lacks inhibitory effect on NP4(3), it may obviously indirectly aid in the binding and inhibition of NP4(3) to alpha 1-PI, by taking care of at least part of the leukocyte elastase. As a specific NP4(3)-inhibitor is not readily available for therapeutic use, this effect may prove useful under in vivo conditions and enhance the protective effect of administered recombinant human SLPI.

Amino Acid Sequence↗

Trapezius muscle changes unrelated to static work load. Chemical and morphologic controlled studies of 22 women with and without neck pain.

From a cross-sectional study of 82 women who were engaged in assembly work that involved static muscle loading of the shoulder muscles, 11 cases with complaints of neck tension (all except 1 arising at work) and 11 individually matched, exposed control cases without neck pain were studied. In addition, 10 matched, unexposed control cases were studied. Upon histochemical examination and study of the trapezius muscle, morphologic changes of type ragged red fibers were found in 8/11 neck-pain cases, in 7/11 exposed controls, and in 4/10 unexposed controls. The pathologic and clinical importance of rare, ragged red fibers in the trapezius muscle thus seems uncertain.

Adult↗

Human cystatin C. role of the N-terminal segment in the inhibition of human cysteine proteinases and in its inactivation by leucocyte elastase.

Leucocyte elastase in catalytic amounts was observed to rapidly cleave the Val-10-Gly-11 bond of the human cysteine-proteinase inhibitor cystatin C at neutral pH. The resulting modified inhibitor had size and amino acid composition consistent with a cystatin C molecule devoid of the N-terminal Ser-1-Val-10 decapeptide. Leucocyte-elastase-modified cystatin C had more than 240-fold lower affinity than native cystatin C for papain. Removal of the N-terminal decapeptide of human cystatin C also decreased inhibition of human cathepsins B and L by three orders of magnitude, but decreased inhibition of cathepsin H by only 5-fold. A tripeptidyldiazomethane analogue of of the N-terminal portion of cystatin C was a good inhibitor of cathepsins B and L but a poor inhibitor of cathepsin H. It therefore appears that amino acid side chains of the N-terminal segment of cystatin C bind in the substrate-binding pockets of cathepsins B and L but not in those of cathepsin H. It is argued that the N-terminal cystatin C interaction with cathepsin B is physiologically important and hence that leucocyte elastase could have a function as a regulator of extracellular cysteine-proteinase inhibitory activity at sites of inflammation.

Amino Acid Sequence↗

Transglutaminase differentiation during maturation of human blood monocytes to macrophages.

There are divergent reports in the literature on the character of transglutaminases in monocytes and macrophages. The aim of the present study was to further elucidate the characteristics and functions of various transglutaminases in monocytes and macrophages. Peripheral human blood monocytes were plated and cultured for up to a month and examined for transglutaminase. Freshly prepared monocytes contained cellular Factor XIII only. Successively during culturing, the monocytes matured into macrophages. Cellular Factor XIII correspondingly disappeared and tissue transglutaminase increased during the same time. After approximately 2 weeks in culture only tissue transglutaminase was detected and this remained for the rest of the culturing period. The tissue transglutaminase content was induced by addition of 2 mumols/l retinoic acid. Addition of retinoic acid was not critical for transglutaminase differentiation. Transglutaminase could be associated with phagocytosis of 125I-trypsin-alpha 2-macroglobulin complexes. The phagocytotic capacity of monocytes was approximately 1/4 compared to macrophages cultured for 14 days. Phagocytosis was measured as cellular complex degradation to monoiodo-tyrosine, released to the culture medium. The monocytes and macrophages were incubated at 4 degrees C and 37 degrees C, with and without addition of the transglutaminase inhibitor monodansylthiacadaverine. Addition of 100 mumols/l monodansylthia-cadaverine caused approximately 2/3 inhibition of phagocytosis. These results suggest that transglutaminase differentiates from cellular Factor XIII into tissue type transglutaminase during maturation of monocytes into macrophages and that the differentiation is associated with transglutaminase-dependent phagocytosis.

Animals↗

Pancreatic cationic elastase in porcine experimental pancreatitis.

A radioimmunoassay for porcine, cationic, pancreatic elastase (irPE) is described. Normal porcine serum contains only small amounts of irPE (less than 3 micrograms/l). IrPE in serum and peritoneal exudate from 6 pigs with experimental pancreatitis was found mainly in a molecular form corresponding to free pro-enzyme. The presence of alpha 1-, alpha 2-macroglobulin-bound elastase-like enzymatic activity in the peritoneal exudates from pigs with pancreatitis, however, indicates that the proteinase is to some extent released as the active enzyme. In some pigs with pancreatitis, the elastase-like activity against Succ(Ala) in the peritoneal exudates increased during the experiment, arguing for a progressive activation of pro-elastase. Free proteolytic activity was not observed in any of the peritoneal exudates. This low degree of activation of elastase and the fact that the elastase inhibiting capacity is substantially larger than the trypsin inhibiting capacity in serum and biological fluids, leads us to the conclusion that active elastase is not a factor of principal importance in the pathogenesis of proteinase inhibitor consumption and tissue damage in our experimental pancreatitis model.

Animals↗

Uptake of immunoreactive leukocyte elastase-inhibitor complexes in macrophage-like cells in abscesses.

Leukocyte elastase was demonstrated immunohistochemically not only in PMN-leukocytes in subcutaneous abscesses but also in scattered macrophage-like cells which in addition contained immunoreactive alpha 1-proteinase inhibitor (alpha 1PI) and alpha 2-macroglobulin (alpha 2M). These cells were located mainly in the marginal region of the abscess. It is concluded that the intracellular deposits in the macrophage-like cells represent phagocytized elastase and/or elastase-alpha 1PI and elastase-alpha 2M complexes. A contributing, local production of the inhibitor is, however, not excluded by the present findings.

Abscess↗

Release of dog polymorphonuclear leukocyte cathepsin G, normally and in endotoxin and pancreatitic shock. Isolation and partial characterization of dog polymorphonuclear leukocyte cathepsin G.

Dog polymorphonuclear leukocyte cathepsin G was isolated from a granule extract using a two-step procedure including affinity chromatography on a Trasylol-Sepharose gel and ion-exchange chromatography on a CM 52 column. 22 of the first 24 N-terminal amino acids were determined and showed 83% and 71% identity to those of human and rat cathepsin G, respectively. Total amino-acid composition demonstrated the basic nature of the protein. In an SDS/polyacrylamide-gel electrophoresis the protein showed an Mr of 29,400 compared to the Mr of 26,800 calculated from the total amino-acid composition. The enzyme was shown to form complexes with alpha 1 alpha 2-macroglobulin and alpha 1-proteinase inhibitor. A specific enzyme-linked immunosorbent assay was developed for the determination of cathepsin G/alpha 1-proteinase inhibitor complex in dog plasma and tissue fluids. The mean concentration of cathepsin G in normal dog plasma was determined to be 38 micrograms/l, measured as cathepsin G/alpha 1-proteinase inhibitor complex. When active dog cathepsin G was added to normal dog plasma in vitro, approximately 56% could be measured by the assay. Slow intravenous infusion of a lethal dose of endotoxin in dogs was followed by a marked drop in white blood cell count and thrombocytes and a simultaneous rapid increase in plasma cathepsin G concentration, reaching a maximum level of 150 micrograms/l. Bile-induced experimental pancreatitis in dogs was accompanied by successive increase in cathepsin G levels in plasma as well as in peritoneal exudates, reaching a maximum level of about 300 micrograms/l in plasma and 18 mg/l in the exudates during the late stages of disease.

Acute Disease↗

Porcine pancreatic cationic pro-elastase. Studies on the activation, turnover and interaction with plasma proteinase inhibitors.

Porcine pancreatic cationic pro-elastase was partly purified from pancreatic juice. The pro-enzyme binds slowly to alpha-macroglobulin and alpha 1-proteinase inhibitor. After 24 h incubation with plasma at room temperature more than 50% of the pro-elastase was still recovered in the form of free pro-enzyme. The pro-enzyme was activated by trypsin at neutral pH and by cathepsin B at pH 3.8. In the pig the half-life of i.v. administered pro-enzyme was about 30 min. After injection into the pancreatic duct radioactively labelled pro-elastase appeared in plasma within 30 min, and in peritoneal fluid after about 1 h.

Animals↗

Alpha-2-macroglobulin decreases parallel to albumin and haemoglobin after elective surgery.

Plasma levels of the plasma protease inhibitor alpha-2-macroglobulin (alpha 2-M) were followed for 7 days in 90 patients subjected to various surgical procedures. Alpha 2-M was found to decrease strictly in parallel with the decrease seen for haemoglobin and albumin levels in all patients. Changes were most pronounced after extensive operations; total hip replacement (n = 7), pulmonary resection (n = 11), extensive colo-rectal resection (n = 15), and less pronounced after 'minor' operations; mastectomy (n = 23) proximal gastric vagotomy (n = 5) and moderate colo-rectal resection (n = 29). Levels were lowest on the second to third postoperative day, whereafter they slowly returned to normal, preoperative levels during the 7-day study period. Functional and quantitative alpha 2-M levels almost paralleled each other throughout the 7 days studied. Chromogenic peptide substrate assays indicated circulating plasmin-alpha 2-M complexes, while no protease-alpha 2-M complexes could be demonstrated using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) or isoelectric focusing (IEF) analyses. Local accumulation and consumption of proteins within wounded tissues, together with haemodilution, were probably the major factors responsible for the decreased plasma levels seen. It is concluded that the plasma levels of alpha 2-M decrease after major elective surgery strictly in parallel with the decrease seen in haemoglobin and albumin levels, and that circulating plasmin-alpha 2-M complexes are probable. The decrease seems to be graded, that is, proportional to the extent of the operative trauma, similar to the postoperative increase seen in positive acute-phase proteins. Thus, alpha 2-M cannot be used as an internal, unchanged plasma protein standard for other protein changes seen after trauma.

Adult↗

Distribution and elimination of intravenously injected urinary trypsin inhibitor.

Elimination of human urinary trypsin inhibitor (UTI) after intravenous injection of 125I-labelled UTI was followed by serial plasma and urine samples in three male volunteers. The plasma half-life of 125IUTI during 0-3 h after injection was 33 min and during the following 4 hours the half-life was 2 hours. Free, biologically active inhibitor was found in the urine during the first four hours after injection. Most of the radioactivity in the urine, however, corresponded to free 125I probably released during the degradation of UTI in the kidney. The distribution of UTI was studied after injection of 125IUTI in rats by measurement of radioactivity in excised organs. Fifteen min after the injection 44% of the radioactivity was found in the kidneys and 9% in the liver, implying that the kidneys are the primary site of UTI metabolism.

Adult↗

Release of immunoreactive human neutrophil proteinase 4, normally and in peritonitis.

A specific enzyme-linked immunoassay (ELISA) has been developed for the determination of neutrophil proteinase 4 (NP4) in human plasma/serum and tissue fluids. Comparison of the sequence for the first 20 N-terminal amino acids of NP4, neutrophil elastase and cathepsin G shows that NP4 is distinct from the other two proteases. However, all three show considerable homology. Neither elastase nor cathepsin G show any immunoreactivity when tested in the present ELISA. Normal human plasma contains about 38 micrograms/l of NP4, identified as alpha 1-proteinase inhibitor complexes. This represents about 50% of the total amount of NP4 released in plasma. The remaining 50% is bound by alpha 2-macroglobulin. Blood coagulation leads to a rapid release of NP4 from the leukocytes. Peritonitis is accompanied by a pronounced release of NP4, as shown by a three-to 10-fold increase of NP4 plasma levels and by the NP4 level in peritoneal exudates, which reaches about 40 mg/l in severe cases.

Amino Acid Sequence↗

Regulation of cystatin C activity by serine proteinases.

The effect of four human serine proteinases on the human cysteine proteinase inhibitor, cystatin C, has been studied in vitro. Neutrophil elastase in catalytic amounts was observed to rapidly cleave cystatin C at neutral pH, thereby giving rise to a modified form of the inhibitor lacking the N-terminal Ser1-Val10 decapeptide. The two other leukocyte serine proteinases, cathepsin G and neutrophil proteinase 4, did not catalytically hydrolyse cystatin C bonds. Neither had the seminal plasma serine proteinase, prostate-specific antigen, any effect on cystatin C. The physiological implications of neutrophil elastase catalysed modification of cystatin C are discussed, and recent findings indicating that this reaction also occurs in vivo are reviewed.

Amino Acid Sequence↗

Interleukin-1 receptor antagonist reduces mortality from endotoxin shock.

About five out of 1,000 patients admitted to hospital develop bacterial sepsis leading to shock, the mortality rate for which is high despite antibiotic therapy. The infection results in hypotension and poor tissue perfusion, and eventually leads to the failure of several organ systems. Bacterial endotoxin is thought to be the direct cause of shock in Gram-negative sepsis, because it can cause shock in animals, and antibodies against endotoxin prevent Gram-negative shock in animals and in humans. But, the symptoms of septic shock are the result of the actions of host cytokines induced by the endotoxin. The cytokine interleukin-1 has been implicated as an important mediator of septic shock because it can induce tachycardia and hypotension and act synergistically with tumour necrosis factor to cause tissue damage and death. We now report that a specific interleukin-1 receptor antagonist reduces the lethality of endotoxin-induced shock in rabbits, indicating that interleukin-1 does indeed play an important part in endotoxin shock.

Animals↗

The elimination of secretory leukocyte protease inhibitor (SLPI) after intravenous injection in dog and man.

After an intravenous injection of 35Sulphur-labelled secretory leukocyte protease inhibitor (SLPI) in four dogs, there was a rapid initial clearance (half-life 10 min) of radioactivity and immunoreactive SLPI from plasma. Later, the immunoreactive SLPI cleared more rapidly (T1/2 = 60 min) than the radioactivity, indicating the gradual appearance of radioactive degradation products. Intact recombinant human SLPI as well as radioactive fragments appeared in the urine. The urinary excretion of radioactivity during the first 3 h was less than 10% of the injected dose. After killing at 3 h, the kidneys contained more radioactivity per gram tissue than the other parenchymatous organs. Following an intravenous injection of 125Iodine-labelled native SLPI in three human volunteers, a rapid initial clearance of both protein-bound and total plasma radioactivity (half-life 10 min) was seen. Later, the protein-bound radioactivity cleared slower (half-life 120 min) than the total radioactivity, indicating a progressive degradation of SLPI with release of radioactive fragments to plasma. After 54 h 80-96% of the radioactivity had been excreted in the urine, mainly as free 125Iodine. No intact SLPI was found in the urine. A renal metabolism of SLPI is assumed, which is supported also by the finding of elevated serum levels of SLPI in uraemic patients. The possible therapeutic use of SLPI is briefly discussed.

Adult↗

Release of immunoreactive canine leukocyte elastase normally and in endotoxin and pancreatitic shock.

A specific ELISA has been developed for the determination of alpha 1-proteinase inhibitor-bound leukocyte elastase in canine plasma and tissue fluids. Comparison of the sequence of the first 16 N-terminal amino acids of the isolated canine leukocyte elastase to other elastases indicated moderate homology with porcine pancreatic elastase and pronounced identity with human leukocyte elastase. Normal canine plasma contains about 66 micrograms/l leukocyte elastase measured as elastase alpha 1-proteinases inhibitor complexes. This represents about 70% of the total amount of leukocyte elastase released in plasma. The remaining 30% is bound by alpha 1 alpha 2-macroglobulin. Blood coagulation leads to a rapid release of elastase from the leukocytes. Slow intravenous infusion of a lethal dose of endotoxin into dogs is followed by a marked drop in leukocyte count and a simultaneous rapid increase in plasma leukocyte elastase concentration reaching a plateau level of 2-3 mg/l plasma. Bile-induced pancreatitis in dogs is accompanied by successive increases in leukocyte elastase levels in plasma as well as in peritoneal exudates, reaching a level of about 15 mg/l in the exudates during the late stages of disease.

Amino Acid Sequence↗