Search results for "Complement C1"

International consensus and practical guidelines on the gynecologic and obstetric management of female patients with hereditary angioedema caused by …

2012

Background There are a limited number of publications on the management of gynecologic/obstetric events in female patients with hereditary angioedema caused by C1 inhibitor deficiency (HAE-C1-INH). Objective We sought to elaborate guidelines for optimizing the management of gynecologic/obstetric events in female patients with HAE-C1-INH. Methods A roundtable discussion took place at the 6th C1 Inhibitor Deficiency Workshop (May 2009, Budapest, Hungary). A review of related literature in English was performed. Results Contraception : Estrogens should be avoided. Barrier methods, intrauterine devices, and progestins can be used. Pregnancy : Attenuated androgens are contraindicated and should …

Ultracentrifugation studies on the native form of the first component of human complement (C1)

1976

The modulation of immune complex aggregation by classical pathway-mediated reactions.

1985

Abstract Classical pathway (CP)-triggered reactions of complement-modulated immune complex(IC) aggregation (tetanus toxoid/human anti-tetanus toxoid-IgG; ICs of equivalence) were investigated turbidimetrically during the early stages of reaction. Monospecific Fab'- or Fab-fragments (rabbit) directed against certain complement components were used to block the complement function in normal human serum (NHS). Additionally, parts of the reactions were studied using purified complement components. C1q in serum generated by the addition of EDTA as well as purified C1q were found to increase the IC aggregation. In contrast to C1q, macromolecular C1 is able to inhibit IC aggregation, whereas addit…

An evidence based therapeutic approach to hereditary and acquired angioedema

2014

Purpose of review Hereditary angioedema (HAE) due to C1 esterase inhibitor (C1-INH) deficiency (HAE-C1-INH), HAE with normal C1-INH, and acquired angioedema due to C1-INH deficiency are rare but important diseases that can be associated with significant morbidity and mortality. Research into the pathogenesis of angioedema has expanded greatly and has led to new clinical trials with novel therapeutic agents and strategies. Recent findings Strategies for managing HAE-C1-INH are aimed at treating acute attacks or preventing attacks through the use of prophylactic treatment. Agents available in Europe for treating acute attacks include plasma-derived C1-INH concentrates, a bradykinin B2 recepto…

C1q acts in the tumour microenvironment as a cancer-promoting factor independently of complement activation

2015

Complement C1q is the activator of the classical pathway. However, it is now recognized that C1q can exert functions unrelated to complement activation. Here we show that C1q, but not C4, is expressed in the stroma and vascular endothelium of several human malignant tumours. Compared with wild-type (WT) or C3- or C5-deficient mice, C1q-deficient (C1qa−/−) mice bearing a syngeneic B16 melanoma exhibit a slower tumour growth and prolonged survival. This effect is not attributable to differences in the tumour-infiltrating immune cells. Tumours developing in WT mice display early deposition of C1q, higher vascular density and an increase in the number of lung metastases compared with C1qa−/− mi…

Evidence for Direct Binding of the First Component of Complement, C1, to Outer Membrane Proteins from Salmonella minnesota

1985

The outer membrane of gram-negative bacteria consists of a tight lattice of lipopolysaccharides (LPS), phospholipids, and proteins. It has been shown in E. coli and S. typhimurium that LPS molecules are exclusively localized in the outer layer of the outer membrane (Muhlradt and Golecki 1975; Smit et al. 1975; Funatura and Nikaido 1980). Localization of proteins in the outer membrane is also indicated by the fact that various major outer membrane proteins in association with LPS, serve as receptors for phages (Datta et al. 1977; Mu-TOH et al. 1978; Henning and Jann 1979; Yu and Mizushima 1982) and colicins (Kadner et al. 1979; Konisky 1979).

Immunohistological differential diagnosis of inflammatory colonic diseases.

1984

Immunohistological investigations were carried out on human colonic tissue from, I healthy mucosa, 2 slightly inflamed mucosa, 3 mucosa with ulcerative colitis, 4 mucosa with Crohn's colitis, using antibodies against immunoglobulins and complement components. All our antibodies, including F(ab')2 fragments, demonstrated a progressive increase of labelled cells from healthy mucosa through slightly inflamed mucosa to mucosa with ulcerative colitis, in contrast to a complete absence of labelled cells in cases of Crohn's disease. The results are discussed with regard to their pathogenesis and their clinical significance for the differentiation of ulcerative colitis and Crohn's colitis.

Binding to complement factors and activation of the alternative pathway by Acanthamoeba.

2010

Acanthamoeba can cause severe ocular and cerebral diseases in healthy and immunocompromised individuals, respectively. Activation of complement appears to play an important role in host defence against infection. The exact mechanism, however, is still unclear. The aim of the present study was to investigate the effect of normal human serum (NHS) and normal mouse serum (NMS) on Acanthamoeba trophozoites, the binding of different complement factors to Acanthamoeba and the activation of the complement system. Moreover, we aimed to work out any possible differences between different strains of Acanthamoeba. A virulent T4 strain, a non-virulent T4 strain and a virulent T6 strain were included in…

Modulation of C1q mRNA Expression and Secretion by Interleukin-1,Interleukin-6, and Interferon-g in Resident and Stimulated Murine Peritoneal Macroph…

2002

The complement system plays an important role in the humoral immune response. Activation of the classical complement pathway is mediated by its subcomponent, C1q. Among the main C1q-synthesising tissues, macrophages have been attributed as a source of particular importance. We investigated the effects of cytokines (IL-1, IL-6 and Interferon-gamma) on local C1q mRNA expression and C1q secretion in resident and in thioglycollate-stimulated murine peritoneal macrophages in vitro. The macrophages were isolated from murine peritoneal lavage fluid, maintained in culture and incubated with the cytokines. Among the cytokines, only IL-6 had a stimulatory effect on C1q production (25% increase vs. co…

Functional C1-inhibitor diagnostics in hereditary angioedema: Assay evaluation and recommendations

2008

Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of potentially life-threatening angioedema. The most widespread underlying genetic deficiency is a heterozygous deficiency of the serine protease inhibitor Cl esterase inhibitor (C1-Inh). In addition to low C4 levels, the most important laboratory parameter for correct diagnosis of HAE or angioedema due to acquired C1-Inh deficiency is reduced C1-Inh function (fC1-Inh). No direct recommendations about the assays for fC1-Inh or sample handling conditions are available, although this would prove especially useful when a laboratory first starts to offer assays on fC1-Inh for HAE diagnosis. In the p…