title: The bone marrow compartment is modified in the absence of galectin-3.
abstract: Galectin-3 (gal-3) is a β-galactoside binding protein present in multivalent complexes with an extracellular matrix and with cell surface glycoconjugates. In this context, it can deliver a variety of intracellular signals to modulate cell activation, differentiation and survival. In the hematopoietic system, it was demonstrated that gal-3 is expressed in myeloid cells and surrounding stromal cells. Furthermore, exogenous and surface gal-3 drive the proliferation of myeloblasts in a granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent manner. Here, we investigated whether gal-3 regulates the formation of myeloid bone marrow compartments by studying galectin-3(-/-) mice (gal-3(-/-)) in the C57BL/6 background. The bone marrow histology of gal-3(-/-) mice was significantly modified and the myeloid compartments drastically disturbed, in comparison with wild-type (WT) animals. In the absence of gal-3, we found reduced cell density and diaphyseal disorders containing increased trabecular projections into the marrow cavity. Moreover, myeloid cells presented limited capacity to differentiate into mature myeloid cell populations in gal-3(-/-) mice and the number of hematopoietic multipotent progenitors was increased relative to WT animals. In addition, bone marrow stromal cells of these mice had reduced levels of GM-CSF gene expression. Taken together, our data suggest that gal-3 interferes with hematopoiesis, controlling both precursors and stromal cells and favors terminal differentiation of myeloid progenitors rather than proliferation.
authors: Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors: C
authors: C
authors: Brand
authors: F L
authors: FL
authors: Oliveira
authors: L
authors: L
authors: Ricon
authors: M L
authors: ML
authors: Fermino
authors: L C
authors: LC
authors: Boldrini
authors: D K
authors: DK
authors: Hsu
authors: F T
authors: FT
authors: Liu
authors: R
authors: R
authors: Chammas
authors: R
authors: R
authors: Borojevic
authors: M
authors: M
authors: Farina
authors: M C
authors: MC
authors: El-Cheikh
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000378:metabolism*; D002454:Cell Differentiation; D037502:Galectin 3 / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D007178:Inbreeding; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D017154:Stromal Cells / Q000166:cytology / Q000378:metabolism
chemical_list: D037502:Galectin 3; D016178:Granulocyte-Macrophage Colony-Stimulating Factor