Analysis of the Antigenic Profile of Uveal Melanoma Lesions with Anti-Cutaneous Melanoma-associated Antigen and Anti-HLA Monoclonal Antibodies

Abstract

The reactivity of 12 surgically removed uveal melanoma lesions with monoclonal antibodies (MoAb) to 14 membrane-bound and 2 cytoplasmic cutaneous melanoma-associated antigens (MAA), to the 2 subunits of HLA Class I antigens and to the gene products of the HLA-D region was compared with that of cutaneous melanoma lesions and correlated with their histiotype. The membrane-bound determinants defined by the anti-M_r 92,000 and 45,000 MAA MoAb TP39.1, anti-M_r 110.000 MAA MoAb M111, anti-M_r 118,000 MAA MoAb TP36.1, anti-M_r 115,000 MAA MoAb 345.134, anti-ICAM-1 MoAb CL203.4 and anti-M_r 31,000 MAA MoAb M2590, and the cytoplasmic determinants defined by the anti-MAA MoAb 465.12 and 2G-10 display a distribution in uveal melanoma lesions similar to that in cutaneous melanoma lesions. On the other hand, the membrane-bound determinants defined by the anti-M_r 100,000 MAA MoAb 376.96, anti-9-O-acetyl-G_D3 ganglioside MoAb ME311 and anti-G_D2-G_D3 ganglioside MoAb ME361 were not detected in the uveal melanoma lesions tested. Furthermore, the membrane-bound determinants defined by the anti-G_D3 MoAb R24, anti-nerve growth factor receptor MoAb ME20.4, anti-M_r 97,000 MAA MoAb 140.240, anti-carcinoembryonic antigen MoAb B1.1 and anti-HMW-MAA 149.53, 225.28, and 763.74 have a markedly lower expression in uveal than in cutaneous melanoma lesions. Incubation of uveal melanoma lesions with the pool of the MoAb 149.53, 225.28, and 763.74 recognizing distinct and spatially distant determinants of the HMW-MAA increased the intensity of staining of six lesions and stained four lesions which were not stained by the individual monoclonal antibodies. The distribution of HLA Class I antigens in uveal melanoma lesions resembles that in cutaneous melanoma lesions, since they are expressed in all the lesions of the mixed and epithelioid type but were not detected in those of the spindle type, i.e., the counterparts of nevocellular nevi. HLA Class II antigens are expressed with a lower frequency in uveal than in cutaneous melanoma lesions, since they were detected only in 2 of the 12 lesions. One of them is of the mixed type and the other one of the epithelioid type. Besides HLA antigens the determinants defined by the anti-carcinoembryonic MoAb B1.1, anti-ICAM-1 MoAb CL203.4, and anti-G_D3 MoAb R24 displayed a differential distribution in the different histiotypes of uveal melanoma, since they are preferentially expressed in lesions of the mixed and epithelioid type.