C1q solid-phase enzymatic microassay for detection of circulating immune complexes: its application in human breast cancer.
Circulating immune complexes (CIC) were detected and quantitated in human breast cancer to monitor the efficiency of mastectomy. For this aim a microimmunoenzymatic test was set up, applying a solid-phase C1q. Features of this assay can be summarized as follows: ability to estimate as low as 10 ng of aggregated human IgG (delta IgG), good reproducibility and simplicity of execution, and small serum sample required. A group of women with breast cancer at different stages (TNM classification) was tested for CIC, and 31.75% were positive. Almost all patients submitted to surgery showed a reduction of this parameter thereafter. A parallel study was carried out in another group of women with benign breast disease, and a significant incidence of CIC was found.