RESUMO
Objective To investigate the difference between mammary gland tissues and breast cancer tissues.Methods Monoclonal antibodies against Mam-A immunized epitopes were screened for immunohistochemical staining of normal breast tissues and breast cancer tissues.The average optical density was used as an index to identify the quantitative data by computer-aided technology to screen epitope-specific antibodies with significant difference in staining characteristics between two types of tissues.Furthermore the feasibility and effectiveness of breast cancer diagnosis were evaluated.Results Four anti-Mam-A epitope-specific monoclonal antibodies,mAb1152,mAb11617,mAb995 and mAb656,were obtained.Immunohistochemical staining showed that the average density of mAb1152,mAb11617 and mAb995 was significantly different between the two types of tissues.The difference was significant between normal breast tissues and breast cancer tissues under the same conditions.The results showed that mAb11617 was better than mAb1152 and mAb995.At the best working point,mAb11617 was the best,the specificity was 90％ and the sensitivity was 59.62％.Further analysis showed that the sensitivity of mAb11617 combined with mAb995 in the diagnosis of in situ breast cancer was 81.48％ and the specificity was 90％,which was of great diagnostic significance.Conclusion There is significant difference between breast tissues and breast cancer tissues in Mam-A protein immunological activity or expression.This difference,which can be recognized by the specific antibody staining and computer aided technology,is of important diagnostic value.