Ultrastruct and biochemical chantes in cultured human malignant melanoma cells after heterotransplantation into nude mice.

Cells from three lines of cultured human malignant melanomas were heterotransplanted into nude mice and then recultered. The shape of the cells, the aspect of the melanosomes, and the content of 5-S-cyteinyldopa showed pronounced changes induced by the transplantation. Such results indicate that this experimental model should be used with great caution. A relationship was found between the shape of the melanosomes and the content of 5-S-cysteinyldopa in the cells.