Circulating Immune Complexes in Human Breast Cyst Fluids: Relationship with Intracystic Immunoglobulin and Electrolyte Levels

Abstract

Circulating immune complexes, the major classes of immunoglobulins and electrolyte concentrations were measured in sixty-two breast cyst fluids aspirated in women affected by gross cystic breast disease. Two main classes of cysts were defined according to the Na/K ratio. Appreciable levels of immunoglobulins were found in almost all samples examined; 66% of breast cyst fluids showed increased levels of immune complexes. A highly significant linear correlation between increased values of immune complexes and immunoglobulin M (p < 0.001) was found in apocrine cysts, characterized by Na/K ratio <3. However, a significant inverse linear correlation was found between positive values of immune complexes and lowered levels of immunoglobulins A (p < 0.001) and G (p < 0.001) in epithelial cysts with Na/K ratio > 3. These data suggest and confirm that the menstrual cycle can also influence or modulate the metabolic activity of human breast cells as a part of the secretory immune system. The relationship between immune complexes and immunoglobulins and electrolyte profiles may provide further knowledge about the immunological features of breast cyst fluid and suggest the possible alteration of immune-response in cystic breast lesions associated with increased cancer risk