Melanoma stained with HMB45 Antibody

HMB45 antibody reacts with a neuraminidase-sensitive oligosaccharide side chain of a glycoconjugate present in immature melanosomes. The HMB45-reactive antigen is present in cutaneous melanocytes, prenatal and infantile retinal pigment epithelium (RPE) and melanoma cells. It is also thought to be oncofetal in nature and has been shown to label the majority of melanomas. Studies support the routine use of HMB45 (anti-gp100) as a sensitive and specific melanocytic marker.