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1.
Vopr Med Khim ; 40(3): 11-5, 1994.
Artigo em Russo | MEDLINE | ID: mdl-8079431

RESUMO

A high level of the membrane-bound proteinase (LMP) secretion by human polymorphonuclear leukocytes (up to 680 nmol/min/ml with N-benzoyl-L-arg-EE as a substrate) was shown during the cell adhesion to receptor-dependent (immobilized aggregates of IgG and C3b) and receptor-independent (DEAE-Sephadex and polymethyl methacrylate) absorbents. Incubation medium contained 6.10(6) cells/ml. The rate of secretion reached the maximal level during 15 min although its level was already high to the 5 min of C3b- and hydrophobic surface-induced activation (491 +/- 55 and 382 nmol/min, respectively). The high level of LMP secretion coincided with the peak of luminol-dependent chemoluminescence during the receptor-dependent adhesion, but did not correlate with a low level of luminescence in the receptor-independent adhesion. Localization of LMP in latent form in neutrophil membrane was shown earlier; the enzyme activation may occur due to effect of polycationic molecules of bovine tissue proteinase inhibitor of Kunitz type, protamine sulfate, alkaline fraction of ampholines. The enzyme (with BAEE as a substrate) was identified as serine proteinase of the trypsin-like type which activated Hageman factor (the XII factor of clotting system) and demonstrated the kininogenase activity. Only slight elastase-like activity was detected after incubation of neutrophils with all the adsorbents studied (0-2 nmol/min/ml with MeOSucAlaAlaProValpNA as a substrate). Chymotrypsin-like activity achieved maximum only by 30 min of activation with all the types of adsorbents (up to 270 nmol/min/ml with N-benzoyl-Tyr-EE as a substrate); this suggests impairment of azurophilic granules and appearance of cathepsin G.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Leucócitos Mononucleares/enzimologia , Receptores de Superfície Celular/metabolismo , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Adesão Celular , Membrana Celular/enzimologia , Complemento C3b , Ativação Enzimática , Humanos , Dados de Sequência Molecular , Oxigênio/metabolismo , Sefarose/análogos & derivados
2.
Biull Eksp Biol Med ; 115(6): 641-2, 1993 Jun.
Artigo em Russo | MEDLINE | ID: mdl-7690617

RESUMO

The capacity of IgG-sepharose, C3b-sephadex and DEAE-sephadex to adsorb human neutrophils after repeated contacts with these cells was studied. A reduction of neutrophil adhesion was found only in experiments with receptor-dependent sorbents (IgG-sepharose, C3b-sephadex). The reduction of adsorption capacity of neutrophil IgG-sepharose was not due to products secreted by cells into the incubation medium or to IgG elimination from the sorbent surface. The data are considered to be a result of ligand molecules modification at the point of neutrophil adhesion contacts with the substrate. The role of this mechanism in neutrophil desorption process is discussed.


Assuntos
Complemento C3b/imunologia , Imunoglobulina G/imunologia , Neutrófilos/imunologia , Adesão Celular/imunologia , Células Cultivadas/imunologia , Meios de Cultura , DEAE-Dextrano , Dextranos , Humanos , Sefarose
3.
Biull Eksp Biol Med ; 114(7): 66-8, 1992 Jul.
Artigo em Russo | MEDLINE | ID: mdl-1384783

RESUMO

The influence of Con A on human neutrophils adhesion in interactions with sepharose 4B, C3b-sephadex G-25, DEAE-sephadex A-25, polymethylmethacrylate was studied. In concentrations 25 mg/ml and more Con A completely inhibited IgG-dependent adhesion but had no influence on other types of adhesion reactions. The effect was due to Con A interaction with neutrophils and could not be reproduced by Con A pretreatment of IgG-sepharose. Results are considered to be a manifestation of lectin-dependent modulation of cell receptors functions.


Assuntos
Concanavalina A/farmacologia , Neutrófilos/efeitos dos fármacos , Dextranos , Géis , Humanos , Indicadores e Reagentes , Lectinas , Metilmetacrilatos , Neutrófilos/fisiologia , Receptores de Superfície Celular/fisiologia , Sefarose/análogos & derivados , Aderências Teciduais
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