BACKGROUND Immunity to infections caused by Streptococcus pneumoniae is dependent on complement. There are wide variations in sensitivity to complement between S. pneumoniae strains that could affect their ability to cause invasive infections. Although capsular serotype is one important factor causing differences in complement resistance between strains, there is also considerable other genetic...

Aim. To compare changes in the complement system C3-glomerulopathy (C3-GP) and atypical hemolytic uremic syndrome (aHUS) after relief of an acute episode thrombotic microangiopathy.
 Materials methods. The study included 8 patients diagnosed with C3-GP aHUS remission. blood levels components were determined: C3, C4, C3a, C5a, factor H (CFH), B (CFB), membrane-attacking complex (MAC), antib...

We have previously described a selective defect of monocyte C3b receptor-mediated phagocytosis in patients with rheumatoid cutaneous vasculitis. We have studied a further 15 rheumatoid arthritis patients with other associated diseases and complications and have identified 4 further patients with a similar defect. Serological and cytochemical studies suggest that the defect in phagocytosis is du...

It was demonstrated that complement-coated sheep erythrocytes bind to Candida albicans cells grown in serum-free RPMI 1640 medium. Testing of purified complement components proved that iC3b and C3d were responsible for the reaction, whereas C3b and C3b-H reacted only slightly if at all. Binding occurred only to C. albicans and C. stellatoidea, not to other species pathogenic to humans. There wa...

Peritoneal macrophages from germfree mice showed a higher basic activity of lysosomal enzymes than did macrophages from conventional mice, whereas oil-induced peritoneal influx, induction of lysosomal enzymes, and phagocytosis via the C3b receptor after endotoxin stimulation were reduced or absent. After germfree mice had been housed with conventional mice for 1 week, peritoneal influx and C3b ...

Complement component C3b has been purified from human, rabbit and bovine serum by affinity chromatography on human factor H-Sepharose after preliminary fractionation by poly(ethylene glycol) and DEAE-Sepharose. The yields are high (35--40%) and the whole process is rapid (3 days). Binding of C3b to factor H-Sepharose is equimolar, has a sharp optimum pH at 7.6 and is quite sensitive to ionic st...

Monoclonal antibodies were used to determine the number and molecular form of C3 bound to particulate activators of the complement (C) system by human serum. Sheep erythrocytes (E) coated with IgM (EIgM) and IgG (EIgG) were used to study activation of the classical pathway (CP). Yeast (Y), rabbit erythrocytes (ER), and five species of bacteria (Escherichia coli, Staphylococcus aureus, Streptoco...

AIM To explore the role of complement system in the T cell activation. METHODS OVA(257-264) CTL epitope and C3b(AN42) encoding genes were synthesized and cloned into expression vector pEGFP-N1. COS-7 cells were transfected with the recombinant plasmid pEGFP-N1. The expression of the fusion protein was determined by FACS. Twenty-four hours after transfection, cultural supernatants of the trans...

A function of P in the alternative complement pathway is to prolong the first order decay of the hemolytic sites on EAC43B in a dose-dependent manner. As the number of initial convertase sites is not changed, even when activated properdin (P) increases the t1/2 10-fold or more, P acts to stabilize rather than to uncover additional sites. P binds to EAC43 to generate EAC43P in a reaction that p...

Using a standardized rosetting technique with IgG-coated ox erythrocytes, avid IgG (Fc) receptors were demonstrated on red cell precursors. The proportion of receptor-positive cells in normal marrows was highest in early precursors and appeared to be lost with maturation. In megaloblastosis, the absolute percentage of early precursors increase, but there is an even greater increase in the propo...