Binding of immunoglobulin G aggregates and immune complexes in human sera to Staphylococci containing protein A.

Abstract

A B S T R A C T Using the

COMPARISON of five assays for immune complexes in the RHEUMATIC DISEASES. An Assessment of Their Validity for Rheumatoid Arthritis

“…Often, however, the diagnosis for a patient with rheumatoid arthritis was a clinical diagnosis after other, nonrheumatoid, causes had been excluded. This category included 10 patients with vasculitis, 16 patients with Sjogren's syndrome, 2 patients with Felty's syndrome, and 9 patients with pleuropulmonary disease. Scleromalacia was found in 4 patients, all of whom had additional features, listed above.…”

“…Five assays for immune complexes, performed in a single laboratory and referred to a common standard, were used: the bovine conglutinin assay (BCA) (14), the '251-Clq binding assay (ClqBA) (13, the monoclonal rheumatoid factor inhibition assay (mRF) (3), the Raji cell assay (4), and the staphylococci binding assay (SBA) (16 …”

Adult-onset still's disease.

“…Circulating immune complexes were tested by a Clq binding assay (13) and monoclonal rheumatoid factor assay, as described previously (14). In patients with active disease, the staphylococcal A binding assay (15) was also performed. The clearance of autologous technetiumlabeled, heat-damaged red blood cells (16) was used as an index of splenic function (17).…”

An adsorption procedure to increase the specificity of enzyme‐linked immunosorbent assays for lyme disease without decreasing sensitivity

“…We therefore elected to use an adsorption procedure to help reduce nonspecific binding when performing initial screenings for antibodies to B burgdorferi. Selection of an appropriate bacterium for adsorption required that: 1) it not be closely related to B burgdorferi, and 2) it not have protein A-like binding properties similar to StaphyIococcus uurei~s (9,14). Both of these requirements were met with the use of E coli.…”