Dendritic cell development in long-term spleen stromal cultures.
The cellular microenvironments in which dendritic cells (DCs) develop are not known. DCs are commonly expanded from CD34+ bone marrow precursors or blood monocytes using a cocktail of growth factors including GM-CSF. However, cytokine-supported cultures are not suitable for studying the intermediate stages of DC development, since progenitors are quickly driven to become mature DCs that undergo limited proliferation and survive for only a short period of time. This lab has developed a long-term culture (LTC) system from spleen which readily generates a high yield of DCs. Hematopoietic cells develop under more normal physiological conditions than in cultures supplemented with cytokines. A spleen stromal cell monolayer supports stem cell maintenance, renewal, and the specific differentiation of only DCs and no other hematopoietic cells. Cultures maintain continuous production of a small population of small-sized progenitors and a large population of fully developed DCs. Cell-cell interaction between stromal cells and progenitor cells is critical for DC differentiation. The progenitors maintained in LTC appear to be quite distinct from bone marrow-derived DC progenitors that respond to GM-CSF. The majority of cells produced in LTC are large-sized cells with a phenotype reflecting myeloid-like DC precursors or immature DCs. These cells are highly endocytotic and weakly immunostimulatory for T cells. This model system predicts in situ production of DCs in spleen from endogenous progenitors, as well as a central role for spleen in DC hematopoiesis.
School of Biochemistry and Molecular Biology, Building #41, Linnaeus Way, Australian National University, Canberra, ACT 0200. Helen.ONeill@anu.edu.au
Helen C
HC
O'Neill
Heather L
HL
Wilson
Ben
B
Quah
Janice L
JL
Abbey
Geneviève
G
Despars
Keping
K
Ni
D000818:Animals; D018952:Antigens, CD34; D002450:Cell Communication; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology*; D006410:Hematopoiesis; D006801:Humans; D013154:Spleen / Q000166:cytology*; D017154:Stromal Cells / Q000166:cytology*
D018952:Antigens, CD34