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At least 37 records · Page 2Linked to original sources
PubMed1992

Influence of plasma proteinase inhibitors and the secretory leucocyte proteinase inhibitor on pancreatic elastase-induced degradation of some plasma proteins.

Pancreatic elastase-induced degradation of some plasma proteins was studied in an in vitro model. The digestion was correlated with the degree of saturation of the alpha 1-proteinase inhibitor (alpha 1PI) and also with varying amounts of secretory leucocyte proteinase inhibitor (SLPI). SLPI was found to inhibit pancreatic elastase showing a Ki of about 10(-7) M for the complex. On the addition of human pancreatic elastase to plasma cleavage of C3, kininogen, fibrinogen and fibronectin was observed when the alpha 1PI approached saturation. In the present in vitro model it was possible to block the cleavage of the four plasma proteins, mentioned above completely with SLPI. Addition of the inhibitor also decreased the consumption of alpha 1PI.

Blood Proteins↗
PubMed1976

Separation of six bovine complement components and one inactivator (1, 2).

Six components (C1, C5, C6, C7, C8 and C9) of bovine complement and one inactivator (C3 in) could be separated from bovine serum. Bovine C1 was separated by precipitation at low molarity (0.03 M of relative salt concentration) other components by DEAE-cellulose chromatography using 0.005 M sodium phosphate buffer, pH 7.5, as a base for solvents having the relative salt concentration adjusted by addition of NaCl from 0.03 to 0.3 M. The separated bovine complement components could be tested using intermediates formed from sheep erythrocytes, rabbit hemolysin, guinea pig C1 and remaining human complement components. C2, C3 and C4 of bovine origin remained undetected either because of incompatibility with the intermediates used or interference of inhibitors or inactivators.

Animals↗
PubMed1975

Alternate complement pathway induction of aggregation and release of 5-hydroxytryptamine and adenosine diphosphate by rabbit platelets.

The present studies investigated patterns of rabbit platelet aggregation and release of 5-hydroxytryptamine (5HT) utilizing nine variables: three different types of challenge, soluble antigen and antibody (AG-AB), zymosan (Z), an agent known to activate the alternate complement pathway (ACP), and Z preincubated in lightly heparinized plasma so as to become coated with complement (ZC); three different types of platelet-rich plasma (PRP), lightly heparinized PRP in which both complement pathways are active, ethylene glycol tetraacetic acid-PRP (EGTA-PRP) in which only the ACP is active, and ethylene diamine tetraacetic acid PRP (EDTA-PRP), which inhibits both complement pathways; three different types of inhibitors, cobra venom factor (CoF), which causes activation of C3 proactivator (C3PA) to C3 activator (C3A) and fluid phase decomplementation of C3 and C5 through C9, adenosine monophosphate (AMP), a specific antagonist of ADP, and tosyl arginine methyl ester (TAME), an inhibitor thought to act not only on the first component of complement, but also on a platelet membrane site of mediating complement-induced platelet injury as well as on C3PAse. In heparinized PRP, both AG-AB and Z produced biphasic aggregation and prompt and extensive 5HT release. A brief lag period noted with both AG-AB and Z challenge was not observed with ZC challenge, indicating that this lag period represented time required for generation of the necessary complement-dependent membrane-injuring activity. Prior decomplementation by CoF entirely prevented both aggregation and release by either AG-AB or Z but by ZC, indicating first that fluid-phase ACP activation did not produce platelet injury, and second that ZC had on its surface an activity capable of producing immediate biphasic aggregation and prompt 5HT release without the further participation of later acting complement components. Both AMP and TAME eliminated the second phase of aggregation and diminished or eliminated 5HT release with all three challenges, suggesting that both inhibitors might be operative on similar or identical platelet membrane receptors mediating complement-dependent platelet injury. In EGTA-PRP, AG-AB and Z produced delayed monophasic aggregation and delayed and diminished 5HT release, whereas ZC produced immediate although monophasic aggregation but delayed and diminished 5HT release. This suggested that all three challenges were capable of producing ACP-mediated platelet injury.

Adenosine Diphosphate↗
PubMedDate not supplied

Complement determinations in the synovial fluid and serum of a patient with Erythema nodosum leprosum.

Simultaneous serum and synovial fluid CH50, C1, C4, C2, C1 esterase inhibitor and C3 protein were determined in a patient with acute erythema nodosum leprosum. The pattern of synovial fluid complement activity coupled with the demonstration of multiple lepra bacilli free and within histiocytes is more consistent with an infectious than an immune complex induced synovitis.

Arthritis, Infectious↗
PubMed1979

Effect of a streptococcal preparation on the complement system.

Streptococcal preparation OK-432 (Picibanil), clinically being used as an immunopotentiator, has been shown to activate the complement system either through the classical or the alternative pathway in vitro [15]. In this experiment, OK-432 was found to increase serum complement level in guinea pigs, and in human without malignancy, when investigated by hemolytic assay using sensitized sheep erythrocytes (EA) for the classical pathway activity and unsensitized rabbit erythrocytes (RaE) for the alternative pathway activity. Assay of complement components revealed a significant increase in C3, but decrease in Clq, while no specific tendency was observed in C4, C5, C9, properdin, C3 activator and Cl-inhibitor. These evidences suggested that OK-432 might potentiate immune response of the host by elevating serum complement level, in addition to activate the complement system.

Aged↗
PubMedDate not supplied

[Hereditary angioedema by defict of C1 esterase. Our experience in 8 cases].

Eight cases of hereditary angioedema, all of them with low values of C1-sterase inhibitor are analyzed. In 7 cases the C3 and C4 components of the complement were assessed; the results showed marked descent of C4. The 8 patients came from 4 different families; only 2 of them were males. Six patients presented digestive disorders, reporting colic pain, nausea and vomiting. In 1 of them the abdominal picture was the only evidence of the disease. In 5 patients the angioedema episodes occurred following traumatisms and in 3 because of emotional states. The duration of the attacks varied from several hours to six days. There was a familial history in all cases. Three of the patients had repeated episodes of pharyngolaryngeal angioedema, two of them requiring emergency tracheotomy because of suffocating crisis. Six patients were treated with Epsilon aminocaproic acid (16 to 20 gr daily) or with tranexamic acid (1 to 3 gr. daily). In 4 cases the results were excellent with either of these antifibrinolytic drugs. No side effects were observed in the tranexamic acid therapy whilst they were frequent in the treatment with Epsilon aminocaproic acid.

Adolescent↗
PubMed1978

Phospholipase A2 contamination of cobra venom factor preparations. Biologic role in complement-dependent in vivo reactions and inactivation with p-bromophenacyl bromide.

Cobra venom factor (CoF), the anticomplementary protein in Naja naja cobra venom, is usually purified by sequential ion exchange and gel filtration chromatography. CoF prepared in this manner contains small but significant quantities of phospholipase A2 activity. This acyl hydrolase activity can be simply and efficiently removed on a large scale by treatment of CoF with p-bromophenacyl bromide (BPB), an irreversible modifier of the histidine residue in the active site of phospholipase A2. BPB treatment does not alter the anticomplementary activity of CoF. In vivo experiments utilizing intratracheal injections of control and BPB-treated CoF, as well as pure phospholipase A2, revealed that contaminating phospholipase A2, and not the anticomplementary protein, was responsible for the observed acute neutrophil-associated lung injury. However, phospholipase A2 had no effect on the hypotensive and thrombocytopenic effects of CoF infected intravenously into rabbits. Depletion of circulating C3-C9 by intraperitoneal injections of CoF was not altered by removal of phospholipase A2 activity with BPB.

Acetophenones↗
PubMed1975

Complement component analysis in angiodema. Diagnostic value.

Complement component analysis is valuable for differentiating the various types of angioedema. Patients with hereditary angioedema have decreased levels of C1 esterase inhibitor and C4 in the presence of normal amounts of C3 and C1q. Acquired C1 esterase inhibitor deficiency secondary to malignant disease is also manifested by depressed C1 esterase inhibitor and C4, but decreased C1q levels distinguish it from hereditary angioedema. Normal values for these complement components are found in persons with allergic angioedema.

Angioedema↗
PubMedDate not supplied

[Preparation and clinical assays of Cl esterase inhibitors].

Seven preparation of Cl-estrase inhibitor (Clinh) were prepared from the serum form which factor IX had been absorbed previously. Despite always the same technique and conditions of isolation the degree of Clinh recovery differed, being sometimes fairly low, and ranging from 24% to 56% in relation to the initial plasma. The preparations contained cartain amounts of other proteins from the groups of alpha- and beta-globulins, particularly coeruloplasmin and components of complement C3, C4 and C9. The concentration of these components was low in relation to the concentration of the inhibitor. Some preparations contained also low amount of albumins. The preparation (about 20 thousand Clinh units) was transfused to a patient with congenital deficiency of Cl-esterase inhibitor at the time free of symptoms. The investigation of the blood obtained 30 minutes after transfusion showed complete inhibition of C-L-esterase. Administration of the preparation to the patient at the time of acute oedema caused in 5 episodes rapid regression of oedema or inhibition of its increase, in two cases no evident positive effect was obtained.

Acute Disease↗
PubMed1977

Concomitant presence of tumor-specific cytotoxic and inhibitor lymphocytes in patients with osteogenic sarcoma.

The lack of detectable tumor-specific cytotoxicity by the peripheral blood lymphocytes of patients with cancer may be due to a lack of cytotoxic lymphocytes or the presence of suppressor lymphocytes that inhibit cytotoxic cells. Unfractionated peripheral blood lymphocytes from 12 of 28 patients with osteogenic sarcoma were cytotoxic to osteogenic sarcoma cells in vitro (P less than 0,001). When the peripheral blood lymphocytes from patients whose lymphocytes were not cytotoxic underwent fractionation, a tumor-specific cytotoxic subpopulation was isolated from 11 of 13 patients (P less than 0.0001). Lymphocytes that inhibited cytotoxic activity of autologous tumor-specific cytotoxic lymphocytes were found in four of 10 patients with osteogenic sarcoma but not in six normal controls. Inhibitor lymphocytes form rosettes with sheep erythrocytes and adhere to nylon, whereas cytotoxic lymphocytes have a receptor for C3 but no surface immunoglobulin. The lack of tumor-specific lymphocytotoxicity in some patients can be due to inhibitor lymphocytes.

Cell Fractionation↗
PubMed1975

[Study of a large family with hereditary angioneurotic edema].

A large kindred (156 members) with hereditary angioneurotic edema is reported. 44 members of the family exhibit typical symptoms of the disease: recurring edemas of the skin and episodes of abdominal pain accompanied by vomiting due to mucosal edema in the stomach and intestine. In 32 patients complement studies were performed which in 28 cases revealed decreased levels of C1-inhibitor and almost normal values for C3 concentration. Among 21 members of the family who had never had symptoms of the disease, 7 also had low levels of C1-inhibitor. In 6 of 16 women, attacks often occur in conjunction with menstruation. In 9 of 10 women the symptoms of the disease had worsened during their first pregnancy. 8 patients have been successfully treated with tranexamic acid for 7-20 months.

Adolescent↗
PubMed1979

Complement and coagulation: causative considerations in contrast catastrophies.

Earlier studies suggest that adverse reactions to injected radiographic contrast media are idiosyncratic. In an attempt to gain a better understanding of pathophysiologic events underlying these reactions, rabbit models injected with lethal dose ranges of a cholangiographic contrast material were studied. These animals showed activation of both the complement and coagulation systems. Externally applied heat potentiated complement consumption and increased mortality. Depleting complement components C3-C9 by cobra venom factor did not prevent activation of coagulation or diminish mortality. However, depleting fibrinogen diminished complement activation and markedly diminished mortality. Heparin, administered at several hourly intervals after contrast challenge, also diminished mortality. These studies suggest that the adverse effects of contrast media in this model system are mediated chiefly by the coagulation system, and that complement, if it participates deleteriously, must involve components up to, but not including, C3. A logical role for the inhibitor of C1 esterase in adverse contrast reactions is considered.

Ancrod↗
PubMed1978

Meningococcal infection and proteolytic control.

Cascade enzyme inhibitors (C1-esterase inhibitor, C3b inactivator, antithrombin III) and other major proteolytic enzyme inhibitors (alpha 1 trypsin inhibitor, alpha 1 chymotrypsin inhibitor, inter-alpha-trypsin inhibitor, alpha 2 macroglobulin) as well as C3 and alpha 1 acid glycoprotein, have been examined in the sera of Nigerian patients suffering from meningococcal infection of varied severity. Patients with meningococcaemia had lower serum concentrations of important inhibitors than did patients with localised meningitic infection. Within the coccaemic group, those who died had the lowest values, notably of antithrombin III and alpha 2 macroglobulin (and also of C3). The clinical end-result of meningococcal infection may be related to the degree of disequilibrium of the linked system of proteolytic control induced by the meningococcal endotoxin.

Antithrombin III↗
PubMed1979

Defective activation of the third component of complement in the sera of newborn infants.

The activation of the terminal complement components, C3--9, plays an important role in the host's defense against infection. In the present study, the ability of bacteria to activate the third component of complement (C3) in newborn serum was examined. A variety of bacteria were incubated in test sera at 37 degrees C for 30 min and the percent of available C3 that was activated was measured. Using one strain of Escherchia coli (no. 3), 32% (mean) of the available C3 was activated in sera from 18 newborns, as compared to 85% in sera from their mothers and 79% in sera from 13 normal adults (P less than 0.005). In contrast, using another strain of E. coli (N70), the percent of C3 activated in newborn sera (83%) was the same as in sera from their mothers (81%) or in sera from normal adults (73%). The defective activation of C3 in newborn sera by E. coli was not related to the presence of the K1 antigen. Newborn sera were also challenged with other bacterial species and the activation of C3 was deficient when tested with klebsiellae, but not with staphylococci or streptococci. The defect in newborn sera appeared to be due to a deficiency of a serum factor rather than to the presence of an inhibitor.

Adult↗
PubMed1979

[Clinical and immunological studies on acquired heat contact urticaria (author's transl)].

A case of localized urticaria in an otherwise healthy young woman, produced only by direct contact of the skin with heat, is described. The minimal temperature of urtication was 44 degrees C (immersion of the forearm in hot water for 5 min). Redness and painful oedema immediately developed without reflex flare. Total serum IgG, IgA, IgM, IgE, complement factors C3 and C4, and alpha1-antitrypsin were in the normal range, whereas the C1-inhibitor level was slightly decreased. There was no evidence of circulating immune complexes in the serum. A skin test and a RAST with house dust were positive, but there were no signs of respiratory atopy. An attempt for passive transfer of heat urticaria into the abdominal skin of a rhesus monkey failed, but was successful for house dust. A treatment trial with ketotifen, a new, perorally acting anti-allergic drug, was poorly effective, but dexchlorpheniramine maleate, a classical antihistaminic, in a dose of 12 mg daily completely suppressed the swelling evoked by heat, but not the erythema, suggesting that other tissue or plasma factors than histamine may be involved in the mechanism of heat urticaria in this patient.

Adult↗
PubMed1979

Detection of proteolytic (C 3-cleaving) activity on mouse mastocytoma (P 815) cells and other mouse cell lines by formation of cell contact with C 3-carrying mouse lymphocytes.

Mouse mastocytoma cells (P 815) formed rosettes with normal mouse spleen lymphocytes which had been coated with uncleaved human C 3; this interaction was clearly dependent on the amount of C 3. Lymphocytes treated with C 3 b or buffer alone were ineffective. Formation of cell contact could be inhibited by the presence of protease inhibitors such as diisopropyl fluorophosphate, phenyl methyl sulfonyl fluoride and tosyllysyl chloromethyl ketone. Seve n out of 13 different cell lines behaved like P 815 cells. The results strongly suggested that a proteolytic activity on mouse tumor cells led to a cooperation with uncleaved C 3 on a carrier cell to connect these two cells. We interpreted these data in analogy to the complement-dependent bridge formation mechanism (M. P. Dierich and B. Landen, J. Exp. Med. 1977. 146: 1484): uncleaved C 3, attached to mouse spleen lymphocytes as carriers, becomes cleaved by enzymes associated with the tumor cells tested; by this cleavage, the labile binding site is released on C 3 (nascent C 3 b) and anchors the C 3-carrying cell to the protease-carrying cell; since this labile binding site is short-lived, this process can be induced by membrane-associated proteases only. The nature of the proteases and the biological implications of this process are as yet uncertain.

Animals↗