Project description:Comparison of gene expression of the osteoclast precursor myeloid blast seeded on plastic and on bone, primed with M-CSF for 4 days and culture with M-CSF and RANKL for 1 day. Osteoclasts and macrophages share progenitors that must receive decisive lineage signals driving them into their respective differentiation routes. Macrophage colony stimulation factor M-CSF is a common factor; bone is likely the stimulus for osteoclast differentiation. To elucidate the effect of both, shared mouse bone marrow precursor myeloid blast was pre-cultured with M-CSF on plastic and on bone. M-CSF priming prior to stimulation with M-CSF and osteoclast differentiation factor RANKL resulted in a complete loss of osteoclastogenic potential without bone. This coincided with a steeply decreased expression of osteoclast genes TRACP and DC-STAMP, but an increased expression of the macrophage markers F4/80 and CD11b. Compellingly, M-CSF priming on bone accelerated the osteoclastogenic potential: M-CSF primed cells that had received only one day M-CSF and RANKL and were grown on bone already expressed an array of genes that are associated with osteoclast differentiation and these cells differentiated into osteoclasts within 2 days. This implies that adhesion to bone dictates the fate of osteoclast precursors. Common macrophage-osteoclast precursors may become insensitive to differentiate into osteoclasts and regain osteoclastogenesis when bound to bone or when in the vicinity of bone. Two conditions: Osteoclast precursors on plastic and on bone, n=4, dye swap
Project description:Current models propose that group 2 innate lymphoid cells are generated in the bone marrow. Here we demonstrate that subsets of these cells can differentiate from multipotent progenitors and committed T cell precursors in the thymus, both in vivo and in vitro. These thymic ILC2s can exit the thymus, circulate in the blood and home to peripheral tissues. Ablation of E protein transcription factors greatly promotes the innate lymphoid cell fate at the expense of B and T cell development. Consistently, a transcriptional network centered on the ZBTB16 transcription factor and IL-4 signaling pathway is highly up-regulated due to E protein deficiency. Our results show that ILC2 can still be generated from what are normally considered to be committed T cell precursors, and that this alternative cell fate is restrained by high levels of E protein activity in these cells.
Project description:In osteolytic tumor, bone resportion can be occured after bone metastasis. Bone metastasis of colorectal cancer can induce obvious bone destruction. Aberrant activation of osteoclasts and the precursors is responsible for tumor-induced osteolysis. The biological process of osteoclast precursors could be modified by different tumor microenvironment. Microarrays were used to detail the differentially expressed genes or non-coding RNAs between normal osteoclast precursors and osteoclast precursors treated by secreta from CT-26 cells.
Project description:Comparison of gene expression of the osteoclast precursor myeloid blast seeded on plastic and on bone, primed with M-CSF for 4 days and culture with M-CSF and RANKL for 1 day. Osteoclasts and macrophages share progenitors that must receive decisive lineage signals driving them into their respective differentiation routes. Macrophage colony stimulation factor M-CSF is a common factor; bone is likely the stimulus for osteoclast differentiation. To elucidate the effect of both, shared mouse bone marrow precursor myeloid blast was pre-cultured with M-CSF on plastic and on bone. M-CSF priming prior to stimulation with M-CSF and osteoclast differentiation factor RANKL resulted in a complete loss of osteoclastogenic potential without bone. This coincided with a steeply decreased expression of osteoclast genes TRACP and DC-STAMP, but an increased expression of the macrophage markers F4/80 and CD11b. Compellingly, M-CSF priming on bone accelerated the osteoclastogenic potential: M-CSF primed cells that had received only one day M-CSF and RANKL and were grown on bone already expressed an array of genes that are associated with osteoclast differentiation and these cells differentiated into osteoclasts within 2 days. This implies that adhesion to bone dictates the fate of osteoclast precursors. Common macrophage-osteoclast precursors may become insensitive to differentiate into osteoclasts and regain osteoclastogenesis when bound to bone or when in the vicinity of bone.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:Dendritic cells (DC) are professional antigen-presenting cells that orchestrate immune responses. The human DC population comprises two main functionally-specialized lineages, whose origins and differentiation pathways remain incompletely defined. Here we combine two high-dimensional technologies — single-cell mRNA sequencing and Cytometry by Time-of-Flight (CyTOF), to identify human blood CD123+CD33+CD45RA+ DC precursors (pre-DC). Pre-DC share surface markers with plasmacytoid DC (pDC) but have distinct functional properties that were previously attributed to pDC. Tracing the differentiation of DC from the bone marrow to the peripheral blood revealed that the pre-DC compartment contains distinct lineage-committed sub-populations including one early uncommitted CD123high pre-DC subset and two CD45RA+CD123low lineage-committed subsets exhibiting functional differences. The discovery of multiple committed pre-DC populations opens promising new avenues for the therapeutic exploitation of DC subset-specific targeting.
Project description:Dendritic cells (DC) are professional antigen-presenting cells that orchestrate immune responses. The human DC population comprises two main functionally-specialized lineages, whose origins and differentiation pathways remain incompletely defined. Here we combine two high-dimensional technologies — single-cell mRNA sequencing and Cytometry by Time-of-Flight (CyTOF), to identify human blood CD123+CD33+CD45RA+ DC precursors (pre-DC). Pre-DC share surface markers with plasmacytoid DC (pDC) but have distinct functional properties that were previously attributed to pDC. Tracing the differentiation of DC from the bone marrow to the peripheral blood revealed that the pre-DC compartment contains distinct lineage-committed sub-populations including one early uncommitted CD123high pre-DC subset and two CD45RA+CD123low lineage-committed subsets exhibiting functional differences. The discovery of multiple committed pre-DC populations opens promising new avenues for the therapeutic exploitation of DC subset-specific targeting.
Project description:Genome wide expression analysis of murine bone marrow osteoclast precursor cells that were cultured for 3 days either with macrophage colony stimulating factor (M-CSF) alone to remain as monocytes or M-CSF + receptor activator of NF-kB (RANKL) to differentiate down the osteoclast lineage. Results provide important information on genes that are regulated by RANKL in order to drive commitment to the osteoclast lineage.
Project description:Currently, the clinical role and influence of valproic acid (VPA) on bone homeostasis remains controversial. In the current study, we confirmed that VPA treatment was linked to a decrease in bone mass and bone mineral density (BMD), an effect that is hypothesized to be caused by a VPA-induced elevation in osteoclast formation and activity. RNA-sequencing revealed a prominent increase of miR-6359 expression in VPA-treated osteoclast precursors which has been demonstrated to be responsible for osteoclast differentiation and bone-resorptive activity. VPA-induced miR-6359 upregulation in osteoclast precursors enhanced ROS production by silencing the SIRT3 protein level, followed by activating the MAPK signaling pathways, which promoted osteoclast formation and activity, thereby accelerating bone loss.