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PubMedDate not supplied

The quality of blood used for transfusion.

The current risk of disease transmission through homologous blood transfusion has lead to a revival in the use of autologous blood. The development of a coagulopathy increases the usage of blood and blood products and therefore the risk of disease transmission. Blood salvaged at operation is subjected to physical and humoral activating factors. The potential systems to be activated are located either in the plasma or non red cell cellular elements. Homologous blood and blood salvaged at operation before and after washing was examined for activation of the plasma and cellular systems by measuring the presence of fibrin degradation products (xDP's), activated complement (C3a) and plasminogen activator and inhibitor activity from the plasma systems; and elastase, serotonin, lysophospholipids, leukotriene B4, lysoplatelet factor and phospholipase A2 from the cellular systems. The plasma systems were activated in the salvaged blood which had elevated levels of xDP's and C3a compared to the patient's blood (p less than 0.05). The products of cellular activation were also elevated in operatively salvaged blood (p less than 0.01 for all the above products). The levels xDP's were normal but the levels of C3a increased in stored blood. The levels of the cellular systems, elastase, serotonin and lysoplatelet activating factor, increased with the duration of storage of bank blood. Unwashed and aged stored blood contains potentially harmful products. Consideration should be given to removal of non red cell elements in blood stored for surgery.

Blood Cells↗
PubMed1990

Effect of anticoagulant on biocompatibility in membrane plasmapheresis.

The effect of heparin or citrate anticoagulation on blood cellular, complement pathway and coagulation pathway was investigated in a membrane plasma exchange procedure. Two membrane plasma separators constructed of cellulose di-acetate (CA) and polyvinyl chloride (PVC) were evaluated with heparin or citrate alone for anticoagulation in a 26 year old male with myasthenia gravis. Maximum white blood cell counts decrease was 21% at 30 min for the CA with heparin while no decrease was observed for the other schemes. Platelet counts changes were comparable between heparin and citrate, while the PVC groups showed less changes than the CA groups. The CA groups, regardless of the type of anticoagulant used, indicated that complement activation occurred via the classical pathway within the module in addition to the activation via alternative pathway for the CA with heparin. In the PVC groups, complement activation was noted to occur only when heparin was used for anticoagulation. PT and PTT showed slight increases with citrate, while they were remarkably prolonged with heparin. Citrate showed less changes in cellular and humoral factors compared to heparin. CA with heparin was the most activating combination of membrane material and anticoagulant, while the PVC with citrate was the least activating combination.

Adult↗
PubMed1990

[Allergic reaction and vascular permeability].

The allergic reaction is characterized by an inflammatory phenomenon that comprises a cellular aspect and a vascular aspect. The vascular aspect is linked to the production of several mediators able to induce a vascular hyperpermeability. Among these mediators it is possible to find histamine, prostaglandins, leukotrienes, PAF, neuromediators, kinins, anaphylatoxins.

Animals↗
PubMed1985

Structure and function of human C5a anaphylatoxin. Selective modification of tyrosine 23 alters biological activity but not antigenicity.

Reaction of either human C5a or its des-Arg74 derivative (des-Arg74-C5a) with tetranitromethane under nondenaturing conditions results in selective nitration of only 1 of the 2 tyrosine residues found in these glycopolypeptides. This reactive tyrosyl residue was identified as that found in position 23 of the sequence. Nitrotyrosyl23-C5a and -des-Arg74-C5a were separated from their respective unmodified precursors by cation-exchange fast protein liquid chromatography. These purified derivatives served as reagents for the subsequent preparation of both aminotyrosyl23-C5a and -des-Arg74-C5a as well as photoreactive analogs of C5a. Radioimmunoassays performed with C5a derivatives serving as competing ligands and a murine antihuman C5a monoclonal antibody employed as first antibody demonstrated that selective modification of tyrosine23 did not produce a detectible alteration in the antigenic properties of C5a. By contrast, either nitro- or aminotyrosyl23-C5a was approximately 3-fold less active than native C5a in both bioassays and competitive ligand-receptor binding assays. Additionally, photoreactive derivatives prepared by coupling either N-succinimidyl-6-(4'-azido-2'-nitrophenylamino)-hexanoate or p-nitrophenyl-2-diazo-3,3,3-trifluoropropionate to aminotyrosyl23-C5a at pH 5.0 failed to interact with the neutrophil C5a receptor. These observations suggest that the tyrosyl23 residue of C5a may participate importantly in the binding interactions of this chemotactic factor and its granulocyte receptor.

Affinity Labels↗
PubMed1989

Human erythrocytes inhibit complement-mediated solubilization of immune complexes.

Incubation of precipitable immune complexes (IC) with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed human E were added to human serum or guinea pig serum, binding of IC to the E occurred and IC solubilization was significantly inhibited. By contrast, SRBC did not bind IC nor inhibit IC solubilization. Because IC binding to human E is mediated by CR type 1 (CR1) we evaluated whether CR1 was responsible for the inhibition of IC solubilization. Human E were treated with trypsin or anti-CR1 mAb. Both treatments abrogated IC binding to human E but did not affect the ability of the human E to inhibit IC solubilization. Human E inhibited C activation by IC. Thus, incubation of IC in human serum caused significant activation of C3 and C5, but not C4. However, when IC were incubated in whole blood or with isolated human E and serum, C3 activation by IC was inhibited significantly. In addition, we demonstrated that the C3b generated during C activation by IC deposited on both IC and human E. Thus, human E may compete for nascent C3 generated during C activation by IC. In conclusion, human E inhibit both complement-mediated solubilization of IC and C activation by IC.

Antigen-Antibody Complex↗
PubMedDate not supplied

[The reactivity of pulmonary and hepatic macrophages in normal and prestimulated animals].

The rate of blood clearing of colloidal carbon increased two-fold as compared to the controls 5 days after prodigiosin injection. This was attended by intensified recruitment of macrophages into the alveoli and increase in the number of phagocytizing macrophages in the interstitium of the lungs by 1.5 times above normal. After administration of zymosan granules, the rate of colloid carbon clearance increased 1.5-fold in 5 days and 2.5-fold on the 9th day; the recruitment of macrophages into the alveoli and the number of phagocytizing macrophages in the interstitium of the lungs increased two-fold. At the same time, granuloma-type mononuclear infiltrates formed in the lungs and liver. Prodigiosin injection increases the rate of blood clearance 1.2-fold in animals stimulated by zymosan granules, while the volume of mononuclear infiltration, which acquires a diffuse character, increases 2.5-fold as compared to the value in zymosan stimulated animals. The effects of phagocyte reconciliation may be directly related to exacerbations of chronic inflammatory diseases of different localization.

Animals↗
PubMed1987

Neutrophil chemotactic activity produced by normal and activated human bronchoalveolar lavage cells.

Activated macrophages can secrete a number of mediators that can attract inflammatory cells and enhance secretion of phlogistic substances from these cells. The ultimate effect of activated bronchoalveolar lavage (BAL) cells may be fibrotic lung injury. Inasmuch as pulmonary sarcoidosis is a disease associated with spontaneous activation of macrophages and lymphocytes among BAL cells, cells obtained from patients with sarcoidosis were compared with normal cells. We report that adherent BAL cells in culture from patients with sarcoidosis (n = 21) release during a resting period in vitro more chemotactic activity for neutrophils (PMNs) than do BAL cells from normal individuals (n = 14). After density fractionation of the respiratory cells by albumin gradient, cells from high-density fractions in the group with sarcoidosis secrete more chemotactic activity for neutrophils than cells from less dense fractions. The PMN chemotactic activity spontaneously released in vitro by BAL cells from patients with sarcoidosis correlates with the percentage of PMNs recovered by BAL. Immunochemical bioassay and high-performance liquid chromatographic (HPLC) analysis of BAL cell supernatants revealed a complex pattern of chemotactic factors to be present. Generally, three peaks of chemotactic activity were noted on HPLC 1-60 separations at greater than 20 kd, 8 to 10 kd, and less than 1 kd apparent molecular weights. Significantly, interleukin-1 was present in these supernatants, whereas complement components and leukotriene B4 were absent. Sarcoid BAL cells, principally alveolar macrophages, are activated in vivo as manifested by spontaneous secretion of chemotactic factors for PMNs in vitro. Interleukin-1 and other less well characterized molecules were detected. The presence of PMNs among the lavage cells of some patients with sarcoidosis appears to be an in vivo biologic correlate of this activation. These data provide additional criteria of BAL cell activation in patients with pulmonary sarcoidosis and provide further evidence concerning factors that attract inflammatory cells into the lung.

Bronchoalveolar Lavage Fluid↗
PubMed1987

Complement activation and vascular injury in systemic lupus erythematosus.

The deposition of immune complexes within blood vessel walls results in the potential for complement activation and the release of chemotactic factors, such as fragments of C5 (C5fr). The generation of C5fr results in the intravascular aggregation of neutrophils with subsequent leukostatic occlusion of the pulmonary arterioles. The generation of C5fr may contribute to the pathogenesis of adult respiratory distress syndrome and other diseases. Studies were undertaken to determine the role of circulating complement derived peptides and intravascular neutrophil activation in systemic lupus erythematosus.

Antigen-Antibody Complex↗