Enrichment of marrow hemopoietic progenitor cells using a blood cell processor

A total of 93 bone marrows (BM) from normal donors and patients were processed using the IBM-COBE 2991 blood cell washer to produce a concentrated buffy coat (BC) for either bone marrow transplantation (BMT) or cryopreservation for subsequent autologous BMT. The reduction in volume was 73.3 +/- 8.5% and nucleated blood cells (NBC) recovery was 87.1 +/- 9.1% of original marrow. Red blood cell (RBC) and platelet (PLT) contamination was reduced 64.5 +/- 10.9% and 41.2 +/- 24.1%, respectively. Clonogenic activity indicated that the NBC fraction was highly enriched in hematopoietic progenitor cells (greater than 100%) as assessed in vitro (CFU-GM). Results were not affected by diagnosis, initial marrow volume or cell count of the BM suspension. We conclude that this is a simple and reproducible method using blood bank, facilities and permits BC preparation from BM without significant loss of hematopoietic progenitor cells.