Sources/Clones
Accurate (KG7/30), Axell/Accurate (F8/86, polyclonal), Biodesign (101, 102, 103), Biogenesis (37-56/3, 21-43, WF7, polyclonal), Biogenex (polyclonal), Biomeda (polyclonal), Chemicon, Diagnostic Biosystems (polyclonal), Dako (F8/86, polyclonal), Sanbio (KG7/30), Serotec (F8, F8/86) and Zymed (Z002, polyclonal).
Fixation/Preparation
The antigen is fixation resistant. Proteolytic digestion or HIER enhances immunoreactivity.
Background
Factor VIII-related antigen is more appropriately known as the von Willebrand factor (Marder et al, 1985). Factor VIII is a glycoprotein and is complexed with factor VIII-related antigen in plasma. Factor VIII is also present in endothelial cells, where it shows a granular pattern of reactivity, and in the cytoplasm of megakaryocytes.
Applications
Factor VIII-related antigen or von Willebrand factor was one of the first markers employed for endothelial cell differentiation in angiosarcomas (Sehested & Hon-Jensen, 1981), but it soon became apparent that the von Willebrand factor is seldom expressed in poorly differentiated vascular tumors (Swanson & Wick, 1993). Other markers of endothelial cells provide a higher diagnostic yield and they include CD 34, CD 31 (Appendix 1.23) and Ulex europaeus agglutinin I. There is also considerable overlap between the expression of von Willebrand factor in vascular and lymphatic endothelium (Suthipintawong et al, 1995).
Von Willebrand factor remains a sensitive marker of benign blood vessels and has been used for the study of angiogenesis in neoplasms such as breast cancer (Weidner et al, 1991).
Comments
Von Willlebrand factor must be used in conjunction with other more sensitive markers of endothelial cells when identifying angiosarcomas. It should be noted that seepage of the antigen may occur from surrounding blood, particularly in hemorrhagic or vascular lesions, and interpretation should be made with caution in such situations.
References
•Marder VJ, Mannucci PM, Firkin BG et al 1985 Standard nomenclature for factor VIII and von Willebrand factor: a recommendation by the International Committee on Thrombosis and Haemostasis. Thrombosis and Hemostasis 54: 871-872.
•Sehested M, Hou-Jensen K 1981 Factor VIII-related antigen as an endothelial cell marker in benign and malignant diseases. Virchow's Archives Pathology and Anatomy 391: 217-225.
•Suthipintawong C, Leong AS-Y, Vinyuvat S 1995 A comparative study of immunomarkers for lymphangiomas and hemangiomas. Applied Immunohistochemistry 3: 239-244.
•Swanson PE, Wick MR 1993 Immunohistochemistry of cutaneous tumors. In: Leong AS-Y (ed) Applied immunohisto-chemistry for surgical pathologists. London: Edward Arnold, pp 270-302.
•Weidner N, Semple JP, Welch WR et al 1991. Tumor angiogenesis and metastasis - correlation in invasive breast carcinoma. New England Journal of Medicine 324: 1-8. invasive breast carcinoma. New England Journal of Medicine 324: 1-8.
Bibliografía
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
Accurate (KG7/30), Axell/Accurate (F8/86, polyclonal), Biodesign (101, 102, 103), Biogenesis (37-56/3, 21-43, WF7, polyclonal), Biogenex (polyclonal), Biomeda (polyclonal), Chemicon, Diagnostic Biosystems (polyclonal), Dako (F8/86, polyclonal), Sanbio (KG7/30), Serotec (F8, F8/86) and Zymed (Z002, polyclonal).
Fixation/Preparation
The antigen is fixation resistant. Proteolytic digestion or HIER enhances immunoreactivity.
Background
Factor VIII-related antigen is more appropriately known as the von Willebrand factor (Marder et al, 1985). Factor VIII is a glycoprotein and is complexed with factor VIII-related antigen in plasma. Factor VIII is also present in endothelial cells, where it shows a granular pattern of reactivity, and in the cytoplasm of megakaryocytes.
Applications
Factor VIII-related antigen or von Willebrand factor was one of the first markers employed for endothelial cell differentiation in angiosarcomas (Sehested & Hon-Jensen, 1981), but it soon became apparent that the von Willebrand factor is seldom expressed in poorly differentiated vascular tumors (Swanson & Wick, 1993). Other markers of endothelial cells provide a higher diagnostic yield and they include CD 34, CD 31 (Appendix 1.23) and Ulex europaeus agglutinin I. There is also considerable overlap between the expression of von Willebrand factor in vascular and lymphatic endothelium (Suthipintawong et al, 1995).
Von Willebrand factor remains a sensitive marker of benign blood vessels and has been used for the study of angiogenesis in neoplasms such as breast cancer (Weidner et al, 1991).
Comments
Von Willlebrand factor must be used in conjunction with other more sensitive markers of endothelial cells when identifying angiosarcomas. It should be noted that seepage of the antigen may occur from surrounding blood, particularly in hemorrhagic or vascular lesions, and interpretation should be made with caution in such situations.
References
•Marder VJ, Mannucci PM, Firkin BG et al 1985 Standard nomenclature for factor VIII and von Willebrand factor: a recommendation by the International Committee on Thrombosis and Haemostasis. Thrombosis and Hemostasis 54: 871-872.
•Sehested M, Hou-Jensen K 1981 Factor VIII-related antigen as an endothelial cell marker in benign and malignant diseases. Virchow's Archives Pathology and Anatomy 391: 217-225.
•Suthipintawong C, Leong AS-Y, Vinyuvat S 1995 A comparative study of immunomarkers for lymphangiomas and hemangiomas. Applied Immunohistochemistry 3: 239-244.
•Swanson PE, Wick MR 1993 Immunohistochemistry of cutaneous tumors. In: Leong AS-Y (ed) Applied immunohisto-chemistry for surgical pathologists. London: Edward Arnold, pp 270-302.
•Weidner N, Semple JP, Welch WR et al 1991. Tumor angiogenesis and metastasis - correlation in invasive breast carcinoma. New England Journal of Medicine 324: 1-8. invasive breast carcinoma. New England Journal of Medicine 324: 1-8.
Bibliografía
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
