Sources/Clones
Biogenesis, Biogenex, Labvision Corp, Medac and Signet.
Fixation/Preparation
This antibody is applicable to formalin-fixed, paraffin-embedded tissue sections and cell blocks prepared from pleural and ascitic fluids.
Background
Clone B72.3 represents the monoclonal antibody to tumor-associated glycoprotein (TAG-72) (isotype: IgT1). The immunogen is a membrane-enriched fraction of a breast carcinoma derived from a liver metastases. This antibody recognizes a tumor-associated oncofetal antigen (TAG-72) expressed by a wide variety of human adenocarcinomas (Szpak et al, 1986; Muraro et al, 1988). It reacts with a sialyl-Tn epitope (72 kD) expressed on mucins (Gold & Mattes et al, 1988). TAG-72 expression in fetal tissue is only observed in tissues of the gastrointestinal tract, including the colon, esophagus and stomach. Although weak reaction with some tissues of adults has been observed, no reactivity is seen with tissue from organ systems including lymphoreticular, cardiovascular, hepatic, pulmonary, neural, muscular, skin, endocrine and genitourinary tract.
Applications
Immunoreactivity of TAG-72 has been observed in 19 of 22 (86%) pulmonary adenocarcinomas (Szpak et al, 1986). In contrast, none of the 20 mesotheliomas studied showed reactivity with this antibody. Other studies have confirmed these findings that malignant mesotheliomas generally do not react with this antibody and if they do, the reactivity is weak. Alternatively, adenocarcinomas from a variety of sites show strong, usually focal and predominantly cytoplasmic reactivity with TAG-72 (Sheibani et al, 1992). This antibody has shown immunoreaction with 84% of invasive ductal breast carcinomas and 85-95% of colon, pancreatic, gastric, esophageal, lung, ovarian and endometrial adenocarcinomas. Other workers have found this antibody to be less sensitive, labeling only 30-40% of adenocarcinomas (Sheibani et al, 1992).
Studies investigating TAG-72 staining of serous effusions have found similar high specificity but with variable sensitivity. Metastatic adenocarcinoma has been reported to be positive in 58-95% of cases from effusion specimens (Shield et al, 1994). Although rare cases of TAG-72 staining in reactive mesothelial cells have been reported (Esteban et al, 1990), other studies did not observe staining in benign, reactive or malignant mesothelial cells.
Comments
Strong reactivity for TAG-72 appears to be relatively specific for adenocarcinoma, but the utility of this antibody is somewhat limited by the variable sensitivity. Nevertheless, it is recommended that TAG-72 be included in an immunodiagnostic panel for evaluation of suspected cases of mesothelioma.
References
•Esteban JM, Tokatar S, Husain S, Battifora H 1990. Immunocytochemical profile of benign and carcinomatous effusions. A practical approach to difficult diagnosis. American Journal of Clinical Pathology 94: 698-705.
•Gold DV, Mattes MJ 1988. Monoclonal antibody B72.3 reacts with a core region structure of O-linked carbohydrates. Tumor Biology 9:137-144. carbohydrates. Tumor Biology 9:137-144.
•Muraro R, Kuroki M, Wunderlich D et al 1988. Generation and characterization of B72.3 second generation monoclonal antibodies reactive with the tumor-associated glycoprotein 72 antigen. Cancer Research 48: 4588-4596.
•Sheibani K, Esteban JM, Bailey A, Battifora H, Weiss LM 1992. Immunopathologic and molecular studies as an aid to the diagnosis of malignant mesothelioma. Human Pathology 23: 107-116.
•Shield PW, Callan JJ, Devine PL 1994. Markers for metastatic adenocarcinoma in serous effusion specimens. Diagnostic Cytopathology 11: 237-245.
•Szpak CA, Johnston WW, Roggli V, et al 1986. The diagnostic distinction between malignant mesothelioma of the pleura and adenocarcinoma of the lung as defined by a monoclonal antibody B72.3. American Journal of Pathology 122: 252-260.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
Biogenesis, Biogenex, Labvision Corp, Medac and Signet.
Fixation/Preparation
This antibody is applicable to formalin-fixed, paraffin-embedded tissue sections and cell blocks prepared from pleural and ascitic fluids.
Background
Clone B72.3 represents the monoclonal antibody to tumor-associated glycoprotein (TAG-72) (isotype: IgT1). The immunogen is a membrane-enriched fraction of a breast carcinoma derived from a liver metastases. This antibody recognizes a tumor-associated oncofetal antigen (TAG-72) expressed by a wide variety of human adenocarcinomas (Szpak et al, 1986; Muraro et al, 1988). It reacts with a sialyl-Tn epitope (72 kD) expressed on mucins (Gold & Mattes et al, 1988). TAG-72 expression in fetal tissue is only observed in tissues of the gastrointestinal tract, including the colon, esophagus and stomach. Although weak reaction with some tissues of adults has been observed, no reactivity is seen with tissue from organ systems including lymphoreticular, cardiovascular, hepatic, pulmonary, neural, muscular, skin, endocrine and genitourinary tract.
Applications
Immunoreactivity of TAG-72 has been observed in 19 of 22 (86%) pulmonary adenocarcinomas (Szpak et al, 1986). In contrast, none of the 20 mesotheliomas studied showed reactivity with this antibody. Other studies have confirmed these findings that malignant mesotheliomas generally do not react with this antibody and if they do, the reactivity is weak. Alternatively, adenocarcinomas from a variety of sites show strong, usually focal and predominantly cytoplasmic reactivity with TAG-72 (Sheibani et al, 1992). This antibody has shown immunoreaction with 84% of invasive ductal breast carcinomas and 85-95% of colon, pancreatic, gastric, esophageal, lung, ovarian and endometrial adenocarcinomas. Other workers have found this antibody to be less sensitive, labeling only 30-40% of adenocarcinomas (Sheibani et al, 1992).
Studies investigating TAG-72 staining of serous effusions have found similar high specificity but with variable sensitivity. Metastatic adenocarcinoma has been reported to be positive in 58-95% of cases from effusion specimens (Shield et al, 1994). Although rare cases of TAG-72 staining in reactive mesothelial cells have been reported (Esteban et al, 1990), other studies did not observe staining in benign, reactive or malignant mesothelial cells.
Comments
Strong reactivity for TAG-72 appears to be relatively specific for adenocarcinoma, but the utility of this antibody is somewhat limited by the variable sensitivity. Nevertheless, it is recommended that TAG-72 be included in an immunodiagnostic panel for evaluation of suspected cases of mesothelioma.
References
•Esteban JM, Tokatar S, Husain S, Battifora H 1990. Immunocytochemical profile of benign and carcinomatous effusions. A practical approach to difficult diagnosis. American Journal of Clinical Pathology 94: 698-705.
•Gold DV, Mattes MJ 1988. Monoclonal antibody B72.3 reacts with a core region structure of O-linked carbohydrates. Tumor Biology 9:137-144. carbohydrates. Tumor Biology 9:137-144.
•Muraro R, Kuroki M, Wunderlich D et al 1988. Generation and characterization of B72.3 second generation monoclonal antibodies reactive with the tumor-associated glycoprotein 72 antigen. Cancer Research 48: 4588-4596.
•Sheibani K, Esteban JM, Bailey A, Battifora H, Weiss LM 1992. Immunopathologic and molecular studies as an aid to the diagnosis of malignant mesothelioma. Human Pathology 23: 107-116.
•Shield PW, Callan JJ, Devine PL 1994. Markers for metastatic adenocarcinoma in serous effusion specimens. Diagnostic Cytopathology 11: 237-245.
•Szpak CA, Johnston WW, Roggli V, et al 1986. The diagnostic distinction between malignant mesothelioma of the pleura and adenocarcinoma of the lung as defined by a monoclonal antibody B72.3. American Journal of Pathology 122: 252-260.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
