Host origin of marrow stromal cells obtained from marrow transplant recipients and transformed in vitro by simian virus-40.

We evaluated the karyotypes of marrow-derived stromal cell lines established by simian virus-40 (SV-40) transformation of long-term cultures from four men who received marrow transplants from women donors. In all cases a normal female karyotype was found in marrow cells. In contrast, a Y chromosome was identified in metaphase cells from the stromal lines, suggesting that following successful marrow transplantation, cells in the marrow microenvironment susceptible to SV-40 transformation remain host in origin.