Search results for "Complement C3a"

Synthesis of complement by macrophages and modulation of their functions through complement activation.

1983

During the last decade considerable progress has been made to characterize intimate functional links between macrophages, a major cellular component of immunoinflammatory responses, and the complement system representing the major humoral mediator of inflammation. Macrophages of various species and tissue sites have been shown to synthesize and release most of the complement components providing these cells with their own \ldpericellular\rd complement system. Circumstantial evidence for the assembly of both classical and alternative pathway convertases has been adduced. An intricate network of feedback loops involving endogenous and extrinsic factors operates to adjust complement production…

Complement split products and proinflammatory cytokines in intraoperatively salvaged unwashed blood during hip replacement: comparison between hepari…

2008

Background and Objectives  The aim of the present study was to investigate the quality of shed blood collected in a new intraoperative autotransfusion system (Sangvia®, AstraTech, Sweden) and to study whether heparin-coated surfaces in the device reduce the production of inflammatory mediators. Material and Methods  The study was randomized and prospective. Twelve total hip arthroplasty patients whose blood was collected with a device having a heparin-coated surface and 12 patients whose blood was collected with a device having a non-heparin-coated surface were included. Venous blood was drawn from the patients preoperatively. Intraoperatively 200 ml salvaged blood was collected and samples…

Comparative study on biological activities of various anaphylatoxins (C4a, C3a, C5a)

1981

Several anaphylatoxic substances (human C3a, guinea pig C3a, human C4a, guinea pig C5a, and a synthetic C3a-related hexapeptide) were compared with regard to their ability to induce secretion of [3H] serotonin from guinea pig platelets. Functional identity of the C3a preparations, C4a, and the hexapeptide was demonstrated by the phenomenon of crossed desensitization. Whereas C3a of human and guinea pig origin proved to be qualitatively and quantitatively identical, C4a expressed only 3% of the activity of the C3 fragments on a molar basis. Investigations with goat anti-guinea pig C3a demonstrate that human and guinea pig C3a possess one antigenic determinant in common; however, this determi…

Complement components in relation to macrophage function

1983

CiC3-1a-Mediated Chemotaxis in the Deuterostome Invertebrate Ciona intestinalis (Urochordata)

2003

Abstract Deuterostome invertebrates possess complement genes, and in limited instances complement-mediated functions have been reported in these organisms. However, the organization of the complement pathway(s), as well as the functions exerted by the cloned gene products, are largely unknown. To address the issue of the presence of an inflammatory pathway in ascidians, we expressed in Escherichia coli the fragment of Ciona intestinalis C3-1 corresponding to mammalian complement C3a (rCiC3-1a) and assessed its chemotactic activity on C. intestinalis hemocytes. We found that the migration of C. intestinalis hemocytes toward rCiC3-1a was dose dependent, peaking at 500 nM, and was specific for…

Beneficial effects of C1 esterase inhibitor in ST-elevation myocardial infarction in patients who underwentsurgical reperfusion: a randomized double-…

2007

Background: The inflammatory cascade has been hypothesized to be an important mechanism of post-ischaemic myocardial reperfusion injury and several studies demonstrated that C1 esterase inhibitor (C1 -INH) is effective in post-ischaemia myocardial protection. Therefore, we aimed to investigate prospectively in a randomised double-blind study the cardioprotective effects of C1-INH in ST segment elevation myocardial infarction (STEMI) in patients who underwent emergent reperfusion with coronary artery bypass grafting (CABG). Methods: In this study, we enrolled 80 patients affected with STEMI who underwent emergent CABG. Patients were assigned in two groups (C1-INH group: receive 1000 Ul of C1…

The Inflammatory Feed-Forward Loop Triggered by the Complement Component C3 as a Potential Target in Endometriosis

2021

Copyright © 2021 Agostinis, Zorzet, Balduit, Zito, Mangogna, Macor, Romano, Toffoli, Belmonte, Morello, Martorana, Borelli, Ricci, Kishore and Bulla. The complement system is a major component of humoral innate immunity, acting as a first line of defense against microbes via opsonization and lysis of pathogens. However, novel roles of the complement system in inflammatory and immunological processes, including in cancer, are emerging. Endometriosis (EM), a benign disease characterized by ectopic endometrial implants, shows certain unique features of cancer, such as the capacity to invade surrounding tissues, and in severe cases, metastatic properties. A defective immune surveillance against…

Is cell salvage safe in liver resection? A pilot study

2007

Abstract Study Objective To investigate the quality of cell salvaged (CS) blood in patients undergoing hemihepatectomy (study group) and compare it with CS-blood from aortic surgery (control group). Design Observational study. Setting Operating room in a university hospital. Measurements 6 patients undergoing hemihepatectomy or aortobifemoral bypass with intraoperative blood loss of more than 800 mL. Samples were drawn from the central venous catheter, from the reservoir of a CS recovery system, and from the processed blood in each patient to determine interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor (TNF), complement C3a, and the terminal complement complex C5b-9. Microbiological ana…

Studies on the mechanism of PMN activation II. by triggering the alternative pathway of complement activation

1982

By means of cobra venom factor (CVF) it is demonstrated that the stimulation of hexosemonophosphate shunt (HMPS) of human polymorphonuclear leukocytes (PMN) by zymosan (Z) and dextran sulfate (DS) is caused by at least two modes of activation: (a) via activation caused by phagocytosis, (b) via activated alternative pathway of complement activation (APC). Active factors of APC presented with phagocytizable objects strongly enhance activation of PMN. The effect of APC can be observed in serum-containing as well as in serum-free cultures. It can be demonstrated that in serum-free cultures the factors of APC participating in the activation of PMN are supplied by monocytes. By the use of synthet…