BACKGROUND Acquired deficiencies of certain complement proteins and impaired opsonisation activity have been implicated in the pathogenesis of the increased susceptibility to infections of patients with alcoholic cirrhosis. METHODS Serum concentrations of C3 and C4, plasma concentrations of C3bc, C9, and the terminal C5b-9 complement complex (TCC), and haemolytic complement activity (classic ...

studies were undertaken to evaluate content of igg, igm, c3, c4, ch50 and proteines of sera from 53 drug addicts by immunological methods. results shows an increase of igg and no significant variatrion in the level of other ig(s). in the same time we have seen an augmentation of gamma globuline in the protein electrophoresis pattern. the level of c3 and c4 of complement component rest unchanged.

BACKGROUND The importance of complement in the pathophysiology of renal disease is still being appreciated. To further address the role of this mediator system, we evaluated the influence of absolute deficiency of C3 and C4 on acute nephrotoxic serum nephritis (NSN). METHODS Selective 'knockout' of C3 and C4 was routinely confirmed in null mice by ELISA. NSN was induced by intravenous injecti...

Erythrocytes coated with varying amounts of human complement were used to detect lymphocytes with complement receptors from normal subjects and patients with chronic lymphocytic leukemia. The relationship between the percentage of lymphocytes rosetting and the quantity of C3 present on complement-coated erythrocytes were studied. Small quantities of C3 (less than 5 fg/erythrocyte) caused maxima...

Complement is viewed as a critical serum-operative component of innate immunity, with processing of its key component, C3, into activation fragments C3a and C3b confined to the extracellular space. We report here that C3 activation also occurred intracellularly. We found that the T cell-expressed protease cathepsin L (CTSL) processed C3 into biologically active C3a and C3b. Resting T cells cont...

Strategies to limit complement deposition on Streptococcus pneumoniae are established as virulence features for invasive disease, but their role in respiratory tract infection requires further analysis. We evaluated complement C3 protein deposition on discordant S. pneumoniae isolates of the same serotype (6A) and their capacity to cause nasopharyngeal (NP) colonization and experimental otitis ...

C3 glomerulopathy (C3G) is characterized by C3 deposits with minimal immunoglobulin deposition caused by alternative complement pathway dysregulation. Unfortunately, no therapeutic intervention has consistently improved outcomes for patients with C3G. Eculizumab, a monoclonal antibody to C5, is currently the only approved complement-specific agent with some efficacy in the treatment of C3 glome...

Streptococcus pneumoniae is a common cause of infection in both HIV positive patients and those with complement deficiencies. We hypothesised that HIV positive individuals might exhibit reduced opsonisation of pneumococcus with complement due to reduced levels of S. pneumoniae specific IgG. We discovered no difference in C3 deposition on S. pneumoniae between HIV positive or negative individual...