The amount of lysis effected by cold agglutinins is directly related to the ability of the antibody to initiate complement activation. This ability is modified by the concentration of antibody, its thermal amplitude (the highest temperature at which the antibody will react with the cell), the degree to which antibody fixation is modified by the presence of complement components (particularly C3...

The complement cascade, traditionally considered an effector arm of innate immunity required for host defense against pathogens, is now recognized as a crucial pathogenic mediator of various kidney diseases. Complement components produced by the liver and circulating in the plasma undergo activation through the classical and/or mannose-binding lectin pathways to mediate anti-HLA antibody-initia...

1. Defects in methods previously proposed for the estimation of complement components are: failure to ensure an excess of the desired components and failure to ensure absence of anticomplementary effects in the dilution ranges used. Existing data are therefore subject to these uncertainties. 2. Methods are proposed for controlling the adequacy of the reagent for each component, for using it in ...

The levels of complement C3 and C4 components were determined in non-indigenous (creoles) and indigenous (Warao) populations, the latter with an extremely high tuberculosis (TB) rate. Serum samples from 209 adults were studied and classified in 4 groups taking into account tuberculin skin tests (TST): (1) the group of Warao patients (58 positive for the TST, WP TST+ and 9 negative for the TST, ...

BACKGROUND Snake Venom Metalloproteinases (SVMPs) are amongst the key enzymes that contribute to the high toxicity of snake venom. We have recently shown that snake venoms from the Bothrops genus activate the Complement system (C) by promoting direct cleavage of C-components and generating anaphylatoxins, thereby contributing to the pathology and spread of the venom. The aim of the present stud...

Complement C3 levels were significantly elevated in subjects with metabolic syndrome compared to the control population (139.95±9.59, 102.12±6.65; p<0.001). Significant difference was also noted in women with metabolic syndrome compared to men with metabolic syndrome (p<0.001).Complement C3 correlated significantly with waist circumference, BMI and total count. C3 also correlated with TC, LDL, ...

Introduction Inherited deficiencies of complement components can result in autoimmunity. Early age of onset, prominent cutaneous manifestations, and presence of anti-Ro antibodies are features suggestive of a complement deficiency. SLE-associated deficiencies in subcomponents of the C1 complex, C1r and/or C1s, were described 4 decades ago, however the molecular basis and functional aspects of t...

Accumulating evidence demonstrates that complement activation is involved in the pathogenesis of osteoarthritis (OA). However, the intimate complement regulation and cross talk with other signaling pathways in joint-associated tissues remain incompletely understood. Recent insights are summarized and discussed here, to put together a more comprehensive picture of complement involvement in OA pa...

The authors report a case of deficiency of the eighth component of complement in a young adult with a history of three episodes of meningitis; one of them proved to be meningococcal. The literature was reviewed and meningitis due to Neisseria meningitidis strains causing disease in complement-deficient and complement-sufficient patients was demonstrated. Meningococcal disease may be the first m...

In vitro studies were performed utilizing sera from a strain of guinea pigs with a total absence of hemolytically active C4. Previous studies in these animals have demonstrated normal complement-dependent inflammatory reactions, suggesting that they are able to bypass their deficiency of C4. In vitro studies with C4-deficient serum also indicate normal activation of late-acting C components. Th...