Fetal spleen stroma drives macrophage commitment.
The role of the fetal spleen in hematopoeisis remains largely unknown. In this particular environment, we show that hematopoietic stem cells do not proliferate, but that they lose multipotency and differentiate exclusively into mature macrophages. B lymphocytes in the spleen derive from committed B cell precursors that are likely to have immigrated from the fetal liver. We developed fetal spleen stromal cell lines that are unique in their capacity to expand myeloid precursors, resulting in large numbers of mature macrophages. These lines secrete high levels of anti-inflammatory molecules. By phenotype, fetal splenic macrophages are reminiscent of their adult counterparts found in the red pulp. We postulate that F4/80(+) splenic macrophages participate in fetal erythropoiesis, as well as in the formation of the splenic architecture.
Bertrand
Julien Y
JY
Unité du Développement des Lymphocytes, INSERM U668, Institut Pasteur, 25, Rue du Dr Roux, 75724 Paris cedex 15, France.
Desanti
Guillaume E
GE
Lo-Man
Richard
R
Leclerc
Claude
C
Cumano
Ana
A
Golub
Rachel
R
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D019070:Cell Lineage / Q000235:genetics / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D005333:Fetus; D005434:Flow Cytometry / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D007150:Immunohistochemistry; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000166:cytology* / Q000196:embryology / Q000378:metabolism; D017154:Stromal Cells / Q000166:cytology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
D000893:Anti-Inflammatory Agents; D017493:Leukocyte Common Antigens