Tissue distribution and biochemical properties of an ocular melanoma- associated antigen

• Published in: The journal of histochemistry and cytochemistry Vol. 33; no. 12; pp. 1190 - 1196
• Main Authors: Donoso, LA, Folberg, R, Edelberg, K, Arbizo, V, Atkinson, B, Herlyn, M
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA Histochemical Soc 01.12.1985; SAGE Publications; Histochemical Society
• Subjects: Antibodies, Monoclonal; Antigens, Neoplasm; Biological and medical sciences; Eye - immunology; Eye Neoplasms - immunology; Eye Neoplasms - pathology; Female; Humans; Immunoenzyme Techniques; Male; Medical sciences; Melanoma - immunology; Melanoma - pathology; Melanoma-Specific Antigens; Molecular Weight; Neoplasm Proteins - analysis; Ophthalmology; Reference Values; Tissue Distribution; Tumors and pseudotumors of the eye, orbit, eyelid, lacrimal apparatus; Human; Immunohistochemistry; Eye; Eye disease; Tumor associated antigen; Melanoma; Tumor; Skin; Monoclonal antibody
• ISSN: 0022-1554; 1551-5044
• DOI: 10.1177/33.12.3905953

A screening method is described to select monoclonal antibodies (Mabs) that bind to ocular melanoma-associated antigens (MAAs) retained in formalin-fixed, paraffin-embedded tissue sections. Small sections of epithelioid or spindle-cell-type uveal melanomas were cut into 2 mm cubes and reembedded in one block. Microslides were cut from this block and used to screen hybridoma supernatant fluid. Using this screening method, three MAbs were selected from two separate fusions of mouse myeloma cells with spleen cells of mice immunized previously with either ocular melanoma cells obtained fresh at enucleation or cells of a cutaneous melanoma cell line. Although all three MAbs showed similar specificities, MAb8-1H showed the strongest immunohistochemical reaction and was studied further in detail. MAb8-1H bound to 91% (71/79) of the choroidal or ciliochoroidal melanomas tested, indicating a high prevalence of this antigen in uveal melanomas. The antigen defined by MAb8-1H was isolated, purified, and partially characterized as a 40,000-50,000 dalton, highly glycosylated protein rich in glycine, serine, and glutamic acid, as is typical of a mucin-type glycoprotein.