Culture perfusion schedules influence the metabolic activity and granulocyte‐macrophage colony‐stimulating factor production rates of human bone marrow stromal cells

Abstract

The metabolic function and GM-CSF production rates of adherent human bone marrow stromal cells were investigated as functions of medium and serum feeding rates. A range of medium exchange schedules was studied, ranging from a typical Dexter culture protocol of one weekly medium exchange to a full media exchange daily, which more closely approximates what bone marrow cells experience in situ. Glucose consumption was found to be significantly higher at full daily exchange rate than at any other exchange schedule examined. However, the lactate yield on glucose was a constant, at 1.8 mol/mol, under all conditions considered. Differential serum vs. medium exchange experiment showed that both serum supply and medium nutrients were responsible for the altered behavior at high exchange rates. Glutamine consumption was found to be insignificant under all culture conditions examined. A change in exchange schedule from 50% daily medium exchange to full daily medium exchange after 14 days of culture was found to result in a transient production of GM-CSF and a change in metabolic behavior to resemble that of cultures which had full daily exchange from day one. These results suggest that both stromal cell metabolism and GM-CSF production are sensitive to medium exchange schedules. Taken together, the data presented indicate that attempts to model the function of human bone marrow in vitro may be well served by beginning with medium exchange schedules that more closely mimic the in vivo physiologic state of bone marrow.

Ex vivo expansion of umbilical cord blood stem cells for transplantation: growing knowledge from the hematopoietic niche

“…Caldwell et al 10 and Schwartz et al 11 demonstrated that slow perfusion and local oxygenation of flat hematopoietic cultures would allow stem cell survival with 10-20-fold progenitor cell expansion with sufficient cells in one or two closed culture vessels. Haylock et al 12 showed that, if sufficient quantities of interleukin-1b (IL-1), IL-3, IL-6, granulocyte colonystimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), and stem cell factor (SCF) were added to suspension cultures of CD34 þ -enriched peripheral blood progenitor cells, progenitor cell expansions of 50-fold or more could be achieved.…”

Angiogenic and Osteogenic Potential of Bone Repair Cells for Craniofacial Regeneration

“…In SPP, the culture medium is continuously replaced with a fresh medium at a slow, controlled rate without the disturbance, removal, or passaging of cells. This technology results in significant expansion of primary human cells 20,21 and has previously demonstrated clinical success in the expansion of bone marrow and blood cells for replenishment of hematopoietic cells after treatment of various blood dyscrasias. [22][23][24][25] Additionally, results of recent in vitro and in vivo studies have generated interest in using this process to produce cells for bone tissue regeneration.…”

Endothelial cell support of hematopoiesis is differentially altered by IL-1 and glucocorticoids

“…Secretion of bioactive molecule by bone marrow stroma cells was demonstrated for some of them. [10][11][12][13][14][15][16] Other stromaderived growth factors are supposed to be necessary for optimal expansion of hematopoietic progenitors.…”