Fig. 1. Immunoblot analyses of LAMP-1. A, LAMP-1 from parental Cloudman S91 melanoma line [S91(6neo)] compared with that from isogenic thioglycollate-induced DBA/2J peritoneal macrophages (). B, LAMP-1 from the same parental melanoma line S91(6neo) compared with macrophage/melanoma artificial fusion hybrids of low (hybrids 95-H3 and 95-H12) and high (hybrids 94-H4, 94-H48, and 95-H1) metastatic potential. PADA and LM6 were two spontaneous in vivo Cloudman S91 hybrids of high metastatic potential (see "Materials and Methods"). Metastatic potentials for these cell lines are shown in Table 1 .