TY - JOUR
T1 - Stem cell factor and FLT3-ligand are strictly required to sustain the long-term expansion of primitive CD34+DR- dendritic cell precursors
AU - Curti, A.
AU - Fogli, M.
AU - Ratta, M.
AU - Tura, S.
AU - Lemoli, R. M.
PY - 2001/1/15
Y1 - 2001/1/15
N2 - We studied cytokine-driven differentiation of primitive human CD34+HLA-DR- cells to myeloid dendritic cells (DC). Hemopoietic cells were grown in long-term cultures in the presence of various combinations of early acting cytokines such as FLT3-ligand (FLT3-L) and stem cell factor (SCF) and the differentiating growth factors GM-CSF and TNF-α. Two weeks of incubation with GM-CSF and TNF-α generated fully functional DC. However, clonogenic assays demonstrated that CFU-DC did not survive beyond 1 wk in liquid culture regardless of whether FLT3-L and/or SCF were added. FLT3-L or SCF alone did not support DC maturation. However, the combination of the two early acting cytokines allowed a 100-fold expansion of CFU-DC for >1 month. Phenotypic analysis demonstrated the differentiation of CD34+DR- cells into CD34-CD33+DR+CD14+ cells, which were inter-mediate progenitors capable of differentiating into functionally active DC upon further incubation with GM-CSF and TNF-α. As expected, GM-CSF and TNF-α generated DC from committed CD34+DR+ cells. However, only SCF, with or without FLT3-L, induced the expansion of DC precursors for >4 wk, as documented by secondary clonogenic assays. This demonstrates that although GM-CSF and TNF-α do not require additional cytokines to generate DC from primitive human CD34+DR- progenitor cells, they do force terminal differentiation of DC precursors. Conversely, FLT3-L and SCF do not directly affect DC differentiation, but instead sustain the long-term expansion of CFU-DC, which can be induced to produce mature DC by GM-CSF and TNF-α.
AB - We studied cytokine-driven differentiation of primitive human CD34+HLA-DR- cells to myeloid dendritic cells (DC). Hemopoietic cells were grown in long-term cultures in the presence of various combinations of early acting cytokines such as FLT3-ligand (FLT3-L) and stem cell factor (SCF) and the differentiating growth factors GM-CSF and TNF-α. Two weeks of incubation with GM-CSF and TNF-α generated fully functional DC. However, clonogenic assays demonstrated that CFU-DC did not survive beyond 1 wk in liquid culture regardless of whether FLT3-L and/or SCF were added. FLT3-L or SCF alone did not support DC maturation. However, the combination of the two early acting cytokines allowed a 100-fold expansion of CFU-DC for >1 month. Phenotypic analysis demonstrated the differentiation of CD34+DR- cells into CD34-CD33+DR+CD14+ cells, which were inter-mediate progenitors capable of differentiating into functionally active DC upon further incubation with GM-CSF and TNF-α. As expected, GM-CSF and TNF-α generated DC from committed CD34+DR+ cells. However, only SCF, with or without FLT3-L, induced the expansion of DC precursors for >4 wk, as documented by secondary clonogenic assays. This demonstrates that although GM-CSF and TNF-α do not require additional cytokines to generate DC from primitive human CD34+DR- progenitor cells, they do force terminal differentiation of DC precursors. Conversely, FLT3-L and SCF do not directly affect DC differentiation, but instead sustain the long-term expansion of CFU-DC, which can be induced to produce mature DC by GM-CSF and TNF-α.
UR - http://www.scopus.com/inward/record.url?scp=0035863811&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035863811&partnerID=8YFLogxK
M3 - Article
C2 - 11145659
AN - SCOPUS:0035863811
VL - 166
SP - 848
EP - 854
JO - Journal of Immunology
JF - Journal of Immunology
SN - 0022-1767
IS - 2
ER -