The Origin of Some Bone Marrow Fibroblasts

An attempt was made to determine the origin of bone marrow fibroblasts which almost always appear when bone marrow aspirates and explants are grown on solid surfaces in tissue culture. Bone marrow aspirates from an individual with chronic myelogenous leukemia demonstrating the Ph-1 chromosome and from an individual with acute leukemia demonstrating C-group trisomy in marrow cells served as sources of the fibroblasts. The fibroblasts that grew from these aspirates were analyzed for the presence of these chromosome markers found in the leukemic cells. The positive findings of the Ph-1 chromosome and C-group trisomy in a proportion of the fibroblasts indicates that at least some leukemic bone marrow fibroblasts are derived from hemopoietic cells. The origin of the bone marrow fibroblasts are derived from hemopoietic somes remains unknown. They could be derived from (1) hemopoietic cells cytogenetically unaffected by the leukemic process, (2) stromal elements of the bone marrow, or (3) both cytogenetically unaffected hemopoietic cells and stromal elements.