[Formation of pseudotypes of VSV after culture in a human melanoma]

Electron microscope studies showed a high production of melanosomes and viral particles budding into the cisternae of the endoplasmic reticulum in cells derived from a subcutaneous metastasis. The history of this subline (HM6B-A) has been summarized elsewhere. An amelanotic subline (provided by the same patient) did not show similar virus particles. When infected with a vesicular stomatitis virus (VSV) thermolabile mutant (tl), these cells produced a VSV pseudotype in which a thermosensitive antigen was modified. Modification of surface VSV antigens was also detected by neutralisation tests. Using these tests, the VSV-pseudotype particles could be used as a tool to detect one or more antigens to a "putative" human melanomavirus, which might be only partially expressed.