Project description:Post-injury remodeling is a complex process involving temporal specific cellular interactions in the injured tissue where the resident fibroblasts play multiple roles, including inflammation induction and tissue remodeling. To dissect the molecular basis of these interactions, we performed single-cell and spatial transcriptome analysis in human and mouse hearts after myocardial infarction. A subset of fibroblasts identified by unique high expression of CD248 was strongly correlated with collagen synthesis and remodeling, and genetic deletion of CD248 in fibroblast ameliorated cardiac fibrosis and dysfunction following ischemia/reperfusion, highlighting the functional importance of CD248 positive fibroblasts in post-injury pathological remodeling. CD248 stabilizes TGF-βR Ⅰ protein and activates ACKR3 expression in fibroblast, leading to enhanced T cell adhesion and retention. This CD248 mediated fibroblast-T cell interaction is required to sustain fibroblast activation and scar expansion in injured heart. Disruption of this interaction using monoclonal antibody or Chimeric antigen receptor T cell reduces T cell infiltration, ameliorates ischemia/reperfusion-induced cardiac fibrosis and improves heart function. Therefore, single cell and spatial molecular profiling in post-injury heart has uncovered a CD248 specific subclass of fibroblast with a critical role in fibroblast-T cell interaction and a new potential therapy to treat tissue fibrosis.
Project description:The interstitial and perivascular spaces of the heart contain stem-like cells including cardiac colony forming units - fibroblast (cCFU-F), a sub-fraction of SCA1+PDGFR-alpha +CD31- (S+P+) immature stromal cells with the qualities of mesenchymal stem cells, that we have characterized previously. Here we explore the role of platelet-derived growth factor receptor (PDGFR-alpha in cCFU-F and S+P+ cell niche regulation in homeostasis and repair. PDGFR-alpha signaling modulated quiescence, metabolic state, mitogenic propensity and colony formation, as well as the rate and stability of self-renewal. Exogenously administered PDGF-AB ligand had anti-aging effects on cCFU-F, akin to those seen in heterochronic parabiotic mice. Post-myocardial infarction (MI), PDGF-AB stimulated S+P+ cell proliferation and conversion to myofibroblasts through a metabolic priming effect, yet significantly enhanced anatomical and functional repair via multiple cellular processes. Our study provides a rationale for a novel therapeutic approach to cardiac injury involving stimulating endogenous repair mechanisms via activation of cardiac stem and stromal cells.
Project description:The interstitial and perivascular spaces of the heart contain stem-like cells including cardiac colony forming units - fibroblast (cCFU-F), a sub-fraction of SCA1+PDGFR-alpha +CD31- (S+P+) immature stromal cells with the qualities of mesenchymal stem cells, that we have characterized previously. Here we explore the role of platelet-derived growth factor receptor (PDGFR-alpha in cCFU-F and S+P+ cell niche regulation in homeostasis and repair. PDGFR-alpha signaling modulated quiescence, metabolic state, mitogenic propensity and colony formation, as well as the rate and stability of self-renewal. Exogenously administered PDGF-AB ligand had anti-aging effects on cCFU-F, akin to those seen in heterochronic parabiotic mice. Post-myocardial infarction (MI), PDGF-AB stimulated S+P+ cell proliferation and conversion to myofibroblasts through a metabolic priming effect, yet significantly enhanced anatomical and functional repair via multiple cellular processes. Our study provides a rationale for a novel therapeutic approach to cardiac injury involving stimulating endogenous repair mechanisms via activation of cardiac stem and stromal cells.
Project description:Cutaneous melanoma is the most aggressive skin cancer showing high mortality at advanced clinical stages. Platelet-Derived Growth Factor Receptor alpha (PDGFR-alpha) is known to strongly inhibit melanoma and endothelial cell proliferation, in vitro as well in vivo. PDGFR-alpha expression has been found to be reduced in metastatic human melanoma-biopsies, as compared to benign nevi-biopsies, thus implying a negative selection of PDGFR-alpha expressing cells, in melanoma. In the present study PDGFR-alpha was transiently overexpressed in endothelial (HUVEC) and melanoma (SK-Mel-28) human cells; a strong anti-proliferation effect was observed, along with profound effects on mRNA and miR- expression. More in detail, gene-expression profiling showed that PDGFR-alpha over-expression affects the expression of 82 genes in HUVEC (41 up-, 41 down-regulated), and 52 genes in SK-Mel-28 (43 up-, 9 down-regulated). miRNA profiling showed that 14 miRs are up-regulated and 40 are down-regulated in PDGFR-alpha overexpressing cells. Accurate validation with alternative techniques demonstrated that CXCL10 gene expression is one of the most significantly up-regulated at both gene- and protein level, in combination with a strong down-regulation of miR-503 in both HUVEC and SK-Mel-28 overexpressing PDGFR-alpha. We then demonstrate that CXCL10 is a validated miR-503 target, and that the anti-proliferation effect of PDGFR-alpha is reverted by specific CXCL-10 neutralization. Several molecular pathways were identified in cells overexpressing PDGFR-alpha, according to KEGG and Gene Ontology analysis (p < 0.01). In conclusion, PDGFR-alpha overexpression strongly inhibits endothelial- and melanoma- proliferation in a CXCL-10 dependent way, by significantly down-regulating miR-503 expression. This dataset contains the results of the microRNA analysis.
Project description:Cutaneous melanoma is the most aggressive skin cancer showing high mortality at advanced clinical stages. Platelet-Derived Growth Factor Receptor alpha (PDGFR-alpha) is known to strongly inhibit melanoma and endothelial cells proliferation, in vitro as well in vivo. PDGFR-alpha expression has been found to be reduced in metastatic human melanoma-biopsies, as compared to benign nevi-biopsies, thus implying a negative selection of PDGFR-alpha expressing cells, in melanoma. In the present study PDGFR-alpha was transiently overexpressed in endothelial (HUVEC) and melanoma (SK-Mel-28) human cells; a strong anti-proliferation effect was observed, along with profound effects on mRNA and miRNA expression. In detail, gene-expression profiling showed that PDGFR-alpha over-expression affects the expression of 82 transcripts in HUVEC (41 up-, 41 down-regulated), and 52 Transcripts in SK-Mel-28 (43 up-, 9 down-regulated). Finally, a miRNA profiling showed that 14 miRs are up-regulated and 39 are down-regulated in PDGFR-alpha overexpressing cells. Accurate validation with alternative techniques demonstrated that CXCL10 is one of the most significantly up-regulated at both gene- and protein level, in combination with a strong down-regulation of miR-503 in both HUVEC and SK-Mel-28 overexpressing PDGFR-alpha. We then demonstrate that CXCL10 is a validated miR-503 target, and that the anti-proliferation effect of PDGFR-alpha is reverted by specific CXCL-10 neutralization. In conclusion, PDGFR-alpha overexpression strongly inhibits endothelial- and melanoma- proliferation in a CXCL-10 dependent way, by significantly down-regulating miR-503 expression. This data set contains the results of the mRNA analysis.
Project description:Post-injury remodeling is a complex process involving temporal specific cellular interactions in the injured tissue where the resident fibroblasts play multiple roles, including inflammation induction and tissue remodeling. To dissect the molecular basis of these interactions, we performed single-cell and spatial transcriptome analysis in human and mouse hearts after myocardial infarction. A subset of fibroblasts identified by unique high expression of CD248 was strongly correlated with collagen synthesis and remodeling, and genetic deletion of CD248 in fibroblast ameliorated cardiac fibrosis and dysfunction following ischemia/reperfusion, highlighting the functional importance of CD248 positive fibroblasts in post-injury pathological remodeling. CD248 stabilizes TGF-βR Ⅰ protein and activates ACKR3 expression in fibroblast, leading to enhanced T cell adhesion and retention. This CD248 mediated fibroblast-T cell interaction is required to sustain fibroblast activation and scar expansion in injured heart. Disruption of this interaction using monoclonal antibody or Chimeric antigen receptor T cell reduces T cell infiltration, ameliorates ischemia/reperfusion-induced cardiac fibrosis and improves heart function. Therefore, single cell molecular profiling in post-injury heart has uncovered a CD248 specific subclass of fibroblast with a critical role in fibroblast-T cell interaction and a new potential therapy to treat tissue fibrosis.
Project description:The scaffold protein synectin plays a critical role in the trafficking and regulation of membrane receptor pathways. As the platelet derived growth factor receptor (PDGFR) pathway is essential for hepatic stellate cell (HSC) activation and liver fibrosis, we sought to determine the role of synectin on the PDGFR pathway in HSC. To study the role of synectin in the development of liver fibrosis, mice with selective deletion of synectin from HSC were generated and found to be protected from fibrosis. RNAseq revealed that knockdown of synectin in HSC demonstrated reductions in the fibrosis pathway of genes including PDGFR-β, but not PDGFR-α. Chromatin Immunoprecipitation assay of the PDGFR-β promoter upon synectin knockdown revealed a pattern of histone marks associated with decreased transcription, dependent on p300. In contradistinction, synectin was found to regulate PDGFR-α through an alternative mechanism: protection from autophagic degradation. Site directed mutagenesis revealed that ubiquitination of specific PDGFR-α lysine residues is responsible for its autophagic degradation. Furthermore, functional studies showed decreased PDGF dependent proliferation and migration after synectin knockdown. Finally, human cirrhotic livers demonstrated increased synectin expression. This work provides insight into differential transcriptional and post-translational mechanisms of synectin regulation of PDGFRs, which are critical to fibrogenesis.