LYSIS OF BLOOD-PLATELETS BY HUMAN OSTEOSARCOMA CELLS IN-VITRO

The in vitro interactions between human osteosarcoma (HOS) cells and p latelets were studied in real time using video-enhanced microscopy. In terference reflection techniques showed that platelets were lysed with in minutes after contacting HOS cells that had been treated with inter feron-gamma. Untreated HOS cells lysed platelets less efficiently. Pla telet lysis depended on platelet-tumor cell contact and on extracellul ar Ca2+. A number of possible mechanisms were excluded. Lysis of plate lets in proximity to tumor cells can provide these with growth factors and thereby contribute to the metastasis-enhancing effect of platelet s.