Immunohistochemical detection of melanoma-associated antigens on formalin-fixed, paraffin-embedded canine tumors.
Seven monoclonal antibodies (Moabs), recognizing melanoma-associated antigens in human tissues, were evaluated for their ability to immunohistochemically stain formalin-fixed, paraffin-embedded canine melanomas. Only 2 Moabs, designated human melanosome-specific antigen (HMSA)-1 and HMSA-5, stained routinely processed canine melanomas, staining 21/35 (60%) and 24/35 (69%), respectively. Twenty-nine of 35 (83%) melanomas tested were stained if results of the 2 Moabs were combined. Monoclonal antibody HMSA-1 also stained neoplastic cells of 10/35 (29%) tumors of nonmelanocytic origin and some neurons and salivary gland epithelial cells in normal canine tissues. However, Moab HMSA-1 staining in the nonmelanocytic tumors, consisting of small, discrete periodic acid-Schiff-positive cytoplasmic droplets, was readily distinguishable from the diffusely granular, cytoplasmic staining of melanocytic tumors. In addition to melanomas, Moab HMSA-5 stained melanocytes and some melanin-containing tumor cells of a pigmented basal cell tumor and melanocytes in normal canine skin. Monoclonal antibodies HMSA-1 and HMSA-5 immunohistochemically identified the majority of canine melanomas, had limited and distinguishable staining in normal tissues and nonmelanocytic tumors, and therefore may be a useful adjunct for the diagnosis of canine melanoma in formalin-fixed, paraffin-embedded tissues.
Berrington
A J
AJ
Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.
Jimbow
K
K
Haines
D M
DM
D000818:Animals; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000032:analysis*; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D005557:Formaldehyde; D007150:Immunohistochemistry; D008545:Melanoma / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D016612:Paraffin Embedding; D016707:Tissue Fixation
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D005557:Formaldehyde