Erythrocytes cultured from bone marrow.

The long-range objective of this study is in vitro tissue culture of bone marrow stem cells to produce erythroid cells of sufficient volume for clinical transfusion. Bone marrow from dogs and patients was cultured in 29 experiments lasting up to 15 weeks. Peripheral erythroid cells from dogs were cultured in three control experiments. Optimal tissue culture media was NCTC 109 augmented with vitamin B12, erythropoietin (EP), folic acid, and 9% fetal protein in 60 mm glass Petri dishes. Additional media and Step III EP was added at 2 to 4 day intervals. Peripheral erythroid cells in culture all were dead within 4 weeks. Marrow erythroic cells in culture proliferated as demonstrated by (1) Fe59 incorporation into cells during culture, (2) H3 thymidine uptake into cultured cells, (3) microscopic evidence of mitoses, and (4) total erythrocyte concentration in cultures far exceeding that of peripheral culture controls. For as yet unexplained reasons the total mature red blood cell concentration in the culture media remained essentially constant throughout the studies. This is a first step in achieving the ultimate goal of bulk erythrocyte production from tissue culture.