The origin of bone marrow fibroblasts.

study these questions, in vitro cell lines with typical cytogenetic abnormalities, such as the Philadelphia chromosome, would be useful. So far, research has been hampered by lack of such cell lines derived from bone marrow. Hentel and Hirschhorn’ reported that a proportion of bone marrow-derived fibroblasts had karyotypic abnormalities identical with those in mitoses observed in the bone marrow itself. We decided to establish fibroblast cultures from cytogenetically abnormal bone marrow cells and to study their biochemical properties. It soon became apparent that only normal karyotypes occurred in our fibroblast cultures. The purpose of this paper is to report and to discuss the discrepancy between our findings and those referred to above.’