[Circulating and tumor tissue-bound immune complexes in patients with breast cancer]

Immunohistochemical studies (detection of immunoglobulins of G, A, and M classes, and C3-fraction of complement) of tumor tissue from 26 patients with mammary gland carcinoma (MGC) were carried out. In 37 patients, circulating immune complexes (IC) in the blood were determined. Conventional histological methods were also used. The level of circulating IC in patients reached 130 +/- 12.6 units, in donors 55 +/- 2.1 units. IC were detected immunohistochemically in 15 cases (57.7%) only. They were predominantly located in the stroma in the form of small and large clumps. As a rule, IC contained one class of immunoglobulins, mostly IgG. In some cases (5 observations) IC were deposited on the surface of carcinoma cells and whole epithelial complexes. In 3 cases, only C3-fraction of complement was found on the carcinoma cell surface which suggested the existence of receptors against complement on the surface of epithelial cells of MGC.