Abstract
The specificity of antibody to NeuGcα2-3Galβ1-4Glc-cer (GM3(NeuGc)) was carefully reexamined by the method of enzyme-immunostaining on a thinlayer plate. The affinity-purified antibody was found to react with NeuGcα2-8NeuGcα2-3Galβ1-4Glc-cer (GD3(NeuGc-NeuGc)) and NeuGcα2-8NeuAcα2-3Galβ1-4Glc-cer (GD3(NeuGc-NeuAc)), but not with NeuAcα2-8NeuGcα2-3Galβl-4Glc-cer (GD3(NeuAc-NeuGc)) or NeuAcα2-8NeuAcα2-3Galβ1-4GIc-cer (GD3(NeuAc-NeuAc)). From this result together with the previous results, it could be concluded that the antibody recognizes the outer portion of molecular species of sialic acids in the gangliosides. By using this antibody, the expression of Hanganutziu-Deicher (HD) gangliosides could be demonstrated in human malignant melanoma. The molecular species were different among individuals examined. Among HD-antigenic gangliosides, GM3(NeuGc) was commonly found in melanoma tissues. One of the patients examined expressed GD3(NeuGc-NeuGc) and GD 3(NeuGc-NeuAc), which may be characteristic gangliosides in human melanomas, since these gangliosides could not be detected in human colon cancer or human fetal tissues.
