Assessment of B/NK/myeloid potentialities in IMF and PV cell fractions. Analysis of the progeny of single CD34+CD38− cells from normal bone marrow (N), PV bone marrow, and IMF peripheral blood. Histograms represent 76 positive clones in 576 plated wells from 3 IMF patients, 386 positive clones in 1482 plated wells from 5 PV patients, and 372 positive clones in 1056 plated wells from 3 normal bone marrows. The experiment was performed once for each patient or control sample. The mean percentage of clones containing one (B, NK, myeloid [M]), 2 (B/M, NK/M, B/NK), or 3 (B/NK/M) lineages per total number of clones analyzed after triple-staining by flow cytometry are shown. Myeloid cells correspond to CD15+ cells, B cells to CD19+ cells, and NK cells to CD56+ cells. Error bars indicate SEM.