The impact of harvest center on quality of marrows collected from unrelated donors.

The total number and distribution of nucleated cells in harvested bone marrow are potentially important determinants of patient outcome following bone marrow transplantation. In order to assess whether marrows collected from predominantly unrelated donors at Georgetown University Medical Center (GUMC) were different in cellular content from marrows collected at harvest centers outside of GUMC, we compared the nucleated cell counts and mononuclear cell subset distribution (CD34, CD3, CD4, CD8, CD19 antigen-positive cell content) of 10 consecutive marrows harvested at GUMC to 10 unrelated donor marrows from outside harvest centers. Significantly higher nucleated cell counts and CD34 antigen-positive cell content and significantly lower CD3 and CD4 antigen-positive T-cell numbers were demonstrated among the marrows harvested at GUMC. These results confirmed significant variability in marrow collection practices between GUMC and 10 different outside harvest centers and suggest that strict adherence to a specific collection procedure, involving small volume marrow aspirations and multiple puncture sites, results in a product with a high number of early hematopoietic progenitor cells and minimal contamination by peripheral blood. These data further suggest the need for careful monitoring of individual unrelated donor marrow collection centers' practices to optimize the quality of the harvested marrow.