Improved "electrophoretic map" of breast cyst fluid proteins.

Human breast cyst fluid (BCF) proteins were evaluated by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) after protein denaturation in the presence or absence of 2-mercaptoethanol. Both electrophoretic techniques yielded characteristic and reproducible banding patterns and achieved a high degree of resolution. The known four major protein bands were identified; silver-staining procedure resulted in more discrete bands (at least 13). Crossed-immunoelectrophoresis analyses of BCF allowed an improved protein mapping of this pathological fluid, presenting the opportunity of simultaneous quantification and identification of at least 22 proteins. The clinical and biological potential of these electrophoretic methods for detecting BCF proteins is discussed.