SB623 cells are expanded from marrow stromal cells (MSCs) transfected with a Notch intracellular domain (NICD)-expressing plasmid. SB623 cells resemble the parental MSCs with respect to morphology and cell surface markers, despite their expansion in culture.
Human adult bone marrow aspirates were plated in growth medium: αMEM supplemented with fetal bovine serum (FBS; 10%) , L-glutamine (2 mM) and penicillin/streptomycin, for three days, to obtain the marrow stromal cell (MSC) monolayer. After two passages, a portion of the culture was cryopreserved as MSCs. The remaining cells (passage 2) were transfected with the pCMV-hNICD1-SV40- NeoR plasmid using Fugene6. After 7 days of selection with 100 μg/ml G418, the G418-resistant colonies were expanded and passed twice prior to cryopreservation as SB623 cells.