Abnormal Antigens in Breast Cancer Tissues and Production of Monoclonal Antibodies Against one of these Antigens

Back ground Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. Objectives This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. Methods One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47.2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr.fasta database search were used for separation and identification of the abnormal proteins. Results Three different patterns of 2D PAGE results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60n XII mutant), X-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rcTPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta-tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against betatropomyosin with a concentration of 0.35mg/ml and a G11 anti betatropomyosin hybridoma cell line were produced. The monoclonal antibody was with single band and approximately 30 KDa molecular weight. However, some tests were done to determine the specificity of the produced monoclonal antibody. Conclusions In conclusion, breast cancer tissues are associated with abnormal antigens, but with low incidence rate; this strongly favors the individualization of breast cancer diagnosis and treatmen