Granulopoiesis-supporting effects of marrow stromal cells in continuous culture from patients with primary myelofibrosis.

The granulopoiesis-supporting effects of marrow adherent cells from seven patients with primary myelofibrosis (PMF) were studied by a continuous allogeneic co-culture system in which the survival of donor granulocyte-macrophage colony-forming cells (CFU-GM) depends upon the supporting ability of adherent cells. Marrow adherent cells from all these seven patients were able to sustain the same number of CFU-GM as those from control subjects. Cytochemical studies showed that colonies grown from cells sustained on fibrous marrow adherent cell layers were predominantly neutrophilic, as were those in control cultures, although many eosinophil colonies grew from patients' bone marrow. These results indicate that marrow stromal cells from PMF patients function normally in their ability to support granulopoiesis.