Search PubMed⌕ Search

Biomedical subjects

I Olsson

Publications and source records attributed to I Olsson.

At least 181 records · Page 10Linked to original sources
PubMed1976

Cytotoxicity for tumor cells of cationic proteins from human neutrophil granules.

Cationic proteins purified from human polymorphonuclear leukocyte granules exert a cytotoxic effect on mammalian tumor cells. This effect is time and concentration dependent, is inhibited by the anionic agent heparin, and is enhanced by preheating the cationic proteins. Other strongly basic proteins (histone, protamine) also exhibited cytotoxic activity. Myeloperoxidase isolated from human leukocytes is cytotoxic when combined with H2O2 and chloride. Under these conditions, the potency of the myeloperoxidase-mediated system is greater than that of the cationic proteins.

Animals↗
PubMed1976

Effects of granulocyte neutral proteases on complement components.

The proteolytic effects of collagenase and elastase from human granulocytes were investigated on the human complement components C3 and C5 in serum and with purified components. The conversion of C3 was analyzed with crossed immunoelectrophoresis as described by Ganrot, and the conversion of C5 was detected with immunoelectrophoresis according to Scheidegger's method. Collagenase converted C3 to C3b but had no detectable effect on C5. Elastase converted C3 to C3b and converted C5 to a C5b-like fragment. The proteolysis by collagenase and elastase in serum was not detectable until the molar ratio for enzyme to the protease inhibitors alpha1-antitrypsin and alpha2-macroglobulin was greater than 1.

Complement C3↗
PubMed1976

Granulopoiesis in infantile genetic agranulocytosis. In vitro cloning of marrow cells in agar culture.

A 3-year-old boy and a 2-year-old girl with infantile genetic agranulocytosis have been studied by in vitro cloning of bone marrow cells in agar culture. The patients display a normal concentration of colony forming cells and the morphological maturation is identical with that of control marrow cultured in vitro. The marrow cells of the patients show some degree of auto-stimulation indicating that endogenous production of colony stimulating factor is operating. As an inverse relationship is expected between the peripheral neutrophil count and the percentage of marrow colony forming cells in S-phase a high percentage was expected. On the contrary, we find that the percentage of colony forming cells in S-phase is extremely low indicating a genetic unresponsiveness of granulopoietic precursor cells to feed back regulation in infantile genetic agranulocytosis.

Agranulocytosis↗
PubMed1976

Mechanisms for the microbicidal activity of cationic proteins of human granulocytes.

One oxygen-independent antimicrobial system of human granulocytes consists of granular chymotropsin-like cationic proteins possessing heat-stable microbicidal activity. For elucidation of the mode of action of the cationic protein, effects on bacterial synthesis of macromolecules, ion transport, and oxygen consumption have been studied. Inhibition of incorporation of radioactive precursors into protein, ribonulceic acid, and deoxyribonucleic acid of both Staphylococcus aureus and Escherichia coli was found concomitantly with inhibition of colony formation. Cationic protein inhibited 86Rb+ influx but did not increase the leakage of intracellular 86Rb+, indicating inhibition of energy-dependent membrane transport without a breakdown of the semipermeable character of the membrane. Oxygen consumption was inhibited. Mg2+ and Ca2+ displayed a protective effect against the microbicidal activity, indicating the operation of charge interactions between cationic protein and bacterial surface. The various effects of cationic protein were more pronounced with S. aureus than with E. coli, parallelling the microbicidal activity.

Blood Bactericidal Activity↗
PubMed1976

Microbicidal mechanisms of human granulocytes: synergistic effects of granulocyte elastase and myeloperoxidase or chymotrypsin-like cationic protein.

The antibacterial activity of a myeloperoxidase (MPO)-glucose oxidase system was found to be greatly increased by granulocyte elastase, present in azurophil granules of human neutrophils. The MPO-H2O3-mediated killing of both Escherichia coli and Staphylococcus aureus was potentiated by granuocyte elastase at an acid pH, whereas at pH 7.4 only killing of E. coli was potentiated. The potentiating effect of elastase was not dependent on the enzymatic properties of the protein since it was not abolished by heating, which destroys the enzymatic activity. A peptide chloromethyl ketone elastase inhibitor abolished both elastolytic activity and the pctentiating effects on MPO-H2-O2-mediated bacterial killing. The antibacterial activity of chymotrypsin-like cationic protein of human neutrophils was also potentiated by elastase. Other degradative enzymes isolated from human granulocytes, e.g., collagenase and lysozyme, did not potentiate MPO-H2O2-mediated or cationic protein-dependent bacterial killing. The present study indicates that a neutrophil constitutent, elastase, which is not microbicidal by itself, can initiate sublethal changes that render some microorganisms more susceptible to the action of microbicidal agents like MPO and chymotrypsin-like cationic protein.

Binding Sites↗
PubMed1976

Elastases from human and canine granulocytes, I. Some proteolytic and esterolytic properties.

The lysosome-like granules of human and canine granulocytes contain an enzyme with elastinolytic activity. The enzymatic behaviour of these elastases was further characterized using the protein substrates elastin-orcein and azocasein and the synthetic substrates tert.-butyloxycarbonyl-alanine p-nitrophenylester (Boc-Ala-ONp) and 3-carboxypropionyl-L-alanyl-L-alanyl-L-alanine p-nitroanilide (Suc-Ala3-NHNp) in photometric assays. The affinities of the granulocyte elastases and of porcine pancreatic elastase to these substrates are very similar, e.g. human granulocyte elastase: KM (Boc-Ala-ONp) = 0.35mM, KM (Suc-Ala3-NHNp) = 1.25mM, porcine pancreatic elastase: KM (Boc-Ala-ONp) = 0.3mM, KM (Suc-Ala3-NHNp) - 1.15mM. The most convenient substrate for the assay of human and dog granulocyte elastases and for kinetic measurements with these enzymes is Suc-Ala3-NHNp. Using this substrate, the dissociation constant of the complex of human granulocyte elastase with human alpha1-antitrypsin could be determined (Ki = 3.5 x 10(-10)M).

Alanine↗
PubMed1976

Granulopoiesis in chronic myeloid leukemia. II. serial cloning of blood and bone marrow cells in agar culture.

Colony-forming cells (CFC) and CFC in S-phase were assayed in chronic myeloid leukemia (CML). A correlation was found between leukocyte counts and CFC of blood, suggesting that the leukocytosis of CML depended on expansion of the committed granulopoietic stem cell compartment. Serial studies performed in four cases demonstrated a decrease of the CFC in S-phase during early stages of developing leukocytosis, which was consistent with the operation of growth control mechanisms. During later stages, serial studies revealed that sudden increments of CFC S-phase coincided with rapidly growing leukocytosis, which was consistent with leukemic cell populations escaping growth control. H-thymidine labeling indices for differentiated precursor cells showed slight variations not coinciding with variations of the CFC S-phase fraction. Cyclic oscillations of the white cell count were observed in one case. The white cell count and the fraction of CFC in S-phase displayed a direct relationship, indicating that the occurence of cycles was not likely to be due to a negative feedback mechanism elaborated by mature granulocytes. In another case, marked cycling of the CFC S-phase fraction was found without distinct oscillations of the white cell count. The present work has emphasized the necessity for serial assays of parameters of cell kinetics in vitro in CML since changing relationships were found between stem cell and differentiated cell kinetics during different phases of the disease.

Adult↗
PubMed1976

Granulocyte function in chronic granulocytic leukemia. II. Bactericidal capacity, phagocytic rate, oxygen consumption, and granule protein composition in isolated granulocytes.

The initial rate of phagocytosis, oxygen consumption rate during phagocytosis, bactericidal capacity against Escherichia coli, and the granule protein composition of isolated mature-appearing granulocytes were studied in 23 patients with chronic granulocytic leukemia (CGL) with the simultaneous use of normal controls. The initial rate of phagocytosis was decreased (p less than 0.05) in the CGL patient group, as were oxygen consumption rate (p less than 0.001) and bactericidal capacity (p less than 0.001). Kinetic analysis of the ingestion rate showed CGL granulocytes to have the same capacity to bind the particles as normal granulocytes. Both specific and primary granule protein deficiencies were shown for CGL granulocytes, and these deficiencies were more pronounced at or near blast cell transformation. Analysis of all different granulocyte function parameters showed an inverse correlation to white blood cell counts (p less than 0.01) and to the percentage of immature granulocytes in peripheral blood (p less than 0.001). The leukocytosis doubling time was progressively shortened during the chronic course of the disease. A correlation was found between granulocyte function parameters and leukocytosis doubling time (p less than 0.001), indicating that granulocyte function was progressively deteriorating during chronic phase CGL, and may be an expression of increasing disturbance of the differentiation process.

Blood Bactericidal Activity↗
PubMed1975

Granulocyte function in chronic granulocytic leukaemia. I. Bactericidal and metabolic capabilities during phagocytosis in isolated granulocytes.

The ingestion, bactericidal activity and metabolism of isolated mature neutrophil leucocytes during phagocytosis was studied in 17 patients with chronic granulocytic leukaemia (CGL) with the simultaneous use of normal controls. Seven patients had received no treatment and the others had been treated previously with Busulphan. The phagocytic indices for killed yeast cells did not differ from those of the controls. A diminished bactericidal activity against E. coli was found in nine CGL cases. The bactericidal capacity closely correlated with the degree of leucocytosis since patients with a WBC count of 90 000/mul or higher with one exception showed decreased bactericidal activities while patients with WBC counts below 90 000/mul with two exceptions showed normal bactericidal activities. The [I-14C]-glucose oxidation during phagocytosis was increased in four patients and decreased in three patients. Some correlation was found between abnormally high or low [I-14C]glucose oxidation and diminished bactericidal activity. The intracellular iodination reaction during phagocytosis was decreased in 10 cases while the extracellular iodination was increased in six cases and decreased in one case. The data for granulocyte iodination did not correlate with WBC count, bactericidal capacity or [I-14C]glucose oxidation. The time course for the bactericidal activity and granulocyte iodination seemed to deviate from the controls indicating a slow initial ingestion and/or degranulation phase. The CGL granulocyte content of myeloperoxidase was normal or increased, the lysozyme content was decreased in half of the cases while the amount of antibacterial cationic proteins was increased, normal or low. The present findings indicate a variety of abnormalities in the mature CGL granulocyte, which are not closely interrelated.

Blood Bactericidal Activity↗
PubMed1975

Cell production and cell function in human cyclic neutropenia.

In vitro studies have been done on haematopoietic cells from a patient with cyclic neutropenia characterized by severe depression of blood neutrophil levels every 21 days. Serial blood counts reveal periodic fluctuations in neutrophils, monocytes and reticulocytes. Agar culture of marrow cells shows normal concentration of colony forming cells. The percentage of colony forming cells in S phase is highly increased during profound neutropenia and normal during the recovery phase relating the granulocyte production to the peripheral neutrophil level. Studies of ingestion rate, bactericidal activity, lactate production and glucose oxidation during phagocytosis in isolated granulocytes show normal results. Also the ingestion rate in isolated monocytes is normal. Serial karyotype analyses of marrow cells during the neutrophil cycle display a normal pattern. Serum myeloperoxidase levels vary inversely with the peripheral neutrophil count indicating increased granulopoietic activity during profound neutropenia, which might be associated with non effective granulopoiesis during profound neutropenia, leading to a lack of granulocyte reserves in the marrow.

Adolescent↗
PubMed1975

Antibacterial activity of cationic proteins from human granulocytes.

Human granulocytes contain several cationic proteins with a molecular weight of approximately 25,000, almost identical amino acid composition, and complete immunologic identity. These proteins possess a chymotrypsin-like protease activity at a neutral pH. The antibacterial activity of the cationic proteins has been studied. Bactericidal activities are found against both Gram-positive (Streptococcus faecalis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) organisms. Gram-positive bacteria are, however, the most sensitive. The pH-optimum is near neutrality, and the microbicidal activity shows an inverse relationship to the ionic strength, indicating an ionic interaction between the cationic proteins and the bacterial surface. The microbicidal effect of the cationic proteins is generally independent of the chymotrypsin-like activity of the same proteins since the activity against several bacterial species is heat stable while the chymotrypsin-like activity is heat labile. The surface properties of S. aureus that are determined by protein A do not seem to influence the susceptibility to cationic proteins. The properties of the Gram-negative envelope of E. coli that determine the susceptibility to the lytic action of serum do not influence the sensitivity to the action of cationic proteins. The present study shows that cationic proteins of human granulocytes represent one potential microbicidal mechanism that is independent of hydrogen peroxide and myeloperoxidase.

Blood Bactericidal Activity↗
PubMed1975

Determination of the glycogen content in single neutrophil leukocytes using a micromodel of leukocyte glycogen.

The kinetics of the periodic acid oxidation as part of the periodic acid-Schiff reaction was studied by combined microinterferometry and microspectrophotometry in micromodel systems of liver glycogen and leukocyte glycogen as well as in neutrophil leukocytes. The initial formation of Schiff-positive chromogens was more rapid in neutrophil leukocytes than in liver or leukocyte glycogen. The chromogen formation was, however, practically complete within 60 min in both neutrophil leukocytes and leukocyte glycogen, but this did not appear to be the case in liver glycogen. Differences in the rate of chromogen formation may depend on various factors such as differences in the source and treatment of the glycogen. The complete periodic acid-Schiff reaction appears to be a measure of the glycogen amount in neutrophil leukocytes and the microdroplet system of leukocyte glycogen is considered to be an appropriate model for the estimation of the glycogen amount in single neutrophil leukocytes. A mean value of 13.3 10-12 g glycogen per normal human neutrophil was found.

Glycogen↗
PubMed1975

Cationic proteins of human granulocytes. V. Interaction with plasma protease inhibitors.

Several cationic proteins of human granulocytes possess chymotrypsin-like and bactericidal activities. The heat-labile chymotrypsin-like activity is inhibited by serum, owing to complex formation with alpha2-macroglobulin and alpha1-antitrypsin. The molar affinity of the cationic proteins for alpha2-macroglobulin is much higher than that for alpha1-antitrypsin. The results indicate that the molar combining ratios are 1:1 for cationic protein to alpha1-antitrypsin and 2:1 for cationic protein to alpha2-macroglobulin. The proteolytic activity against fibrinogen and casein is inhibited by both alpha2-macroglobulin and alpha1-antitrypsin, whereas the activity against small molecular synthetic substrates is inhibited by alpha1-antitrypsin but not alpha2-macroglobulin. The heat-stable bactericidal action of the cationic proteins against Staphylococcus was also inhibited by serum, probably owing to complex formation with alpha2-macroglobulin and alpha1-antitrypsin.

Blood Proteins↗