Related Experiment Video
Updated: Aug 10, 2026

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
Complement C3b receptors on erythrocytes, circulating immune complexes, and complement C3 split products in patients
Abstract:
Twenty-one patients with primary Sjögren's syndrome (SS) and 22 age- and sex-matched healthy controls were examined for levels of C3b receptors (CR1) on erythrocytes (by an enzyme-linked immunosorbent assay), levels of circulating immune complexes (IC) (by a polyethylene glycol precipitation complement consumption method), and C3 split products, C3d and C3c (by intermediate gel rocket immunoelectrophoresis). CR1 varied within a wide range (20-124%), and a preponderance of low numbers was found among patients with primary SS (P less than 0.05). The levels of circulating IC and C3d were elevated in primary SS patients (P less than 0.01) and were mutually correlated (P less than 0.01; tau = 0.5), but levels of circulating IC and C3d did not correlate with CR1 values. C3c concentrations were the same in patients and controls. It is possible that the CR1 level serves as a predictor for the development of IC-induced manifestations, and the C3d concentration serves as an objective parameter for disease activity in primary SS.
Related Concept Videos
Humoral Immune Responses
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Antibody Actions
Neutralization
Antibodies can bind to pathogens, preventing them from infecting host cells. This process...
Complement System
Hypersensitivity Reactions: Cytolytic Reactions
Hypersensitivity Reactions: Immune-Complex Reactions

