Biology subjects

Griscelli, F.

Publications and source records attributed to Griscelli, F..

5 recordsLinked to original sources

bioRxiv2021

Detection of hematopoietic stem cell transcriptome in human fetal kidneys and kidney organoids derived from human induced pluripotent stem cells (iPSC)

BackgroundIn mammalians, hematopoietic stem cells (HSC) arise in the dorsal aorta from the hemogenic endothelium, followed by their migration to fetal liver and to bone marrow. In zebrafish, kidney is the site of primary hematopoiesis. In humans, the presence of HSC in the fetal or adult kidney has not been established. MethodsWe analyzed the presence of HSC markers in human fetal kidneys by analysis of single-cell datasets. We then analyzed in kidney organoids derived from iPSC, the presence of hematopoietic markers using transcriptome analyses. Results12 clusters were identified of stromal, endothelial, and nephron cell type-specific markers in the two fetal stage (17 weeks) kidney datasets. Among these, expression of hematopoietic cells in Cluster 9 showed expression of primitive markers. Moreover, whole transcriptome analysis of our iPSC-derived kidney organoids revealed induction of the primitive hematopoietic transcription factor RUNX1 as found in the human fetal kidney cortex. ConclusionsThese finding support the presence of cells expressing HSC transcriptome in human kidney. The mechanisms of the appearance of the cells with the same transcriptional features during iPSC-derived kidney organoid generation requires further investigation.

developmental biology↗

bioRxiv2020

Evidence of Increased Hemangioblastic and Early Hematopoietic Potential in Chronic Myeloid Leukemia (CML)-derived Induced Pluripotent Stem Cells (iPSC)

Hemangioblasts derived from mesodermal lineage are the earliest precursors of hematopoietic stem cells and endothelial cells. Embryonic stem cells (ESC) and induced pluripotent stem cells (iPSC) are the only experimental systems in which these cells can be assayed and quantified. We show here using CML-derived iPSC and blast-cell colony forming (Bl-CFC) assays that hemangioblasts are highly expanded in CML derived iPSC as compared to human H1-ESC-derived hemangioblasts. BCR-ABL signaling pathway is intact in these cells with evidence of CRK-L phosphorylation which is reduced by the use of Imatinib. Hematopoietic progenitor assays generated using blast-CFC demonstrates also a highly increased hematopoietic progenitor potential of these cells as compared to H1-ESC. The same results were also obtained using hematopoietic progenitor assays via embryoid body formation. In CML iPSC, we have also found a significant reduction of Aryl Hydrocarbon Receptor (AHR) expression which is involved in hematopoietic quiescence. Further inhibition of AHR using StemRegenin (SR1), an AHR antagonist, led to an increase of blast-cell colonies in CML iPSC whereas the use of an AHR agonist inhibited blast cell colonies. Thus, our results show for the first time, the possibility of establishment of a myeloproliferative phenotype using patient-derived iPSC and the presence of a major expansion hemangioblast compartment and derived hematopoietic progenitors in this context. They also suggest that the AHR signaling pathway could represent a novel druggable target in CML.

cancer biology↗

bioRxiv2020

Direct reprogramming of adult hepatocytes to generate LGR5+ endodermal progenitor

We successfully converted hepatocytes isolated from adult mice into expandable and stable leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5)-positive endodermal progenitor cells (EndoPCs). This was accomplished in vitro through transient exposure to four transcriptional factors (OCT3/4, SOX2, KLF4, and cMYC) and STAT3 activators. EndoPCs were generated by a process that involved an epithelial-mesenchymal transition (EMT) without the use of any components of the canonical WNT/{beta}-catenin or LGR5/R-spondin signaling pathways. We showed that the proliferation and capacity for self-renewal of EndoPCs in 2D long-term culture were controlled by three interrelated signaling pathways: gp130/JAK/STAT3, LGR5/R-spondin, and WNT/{beta}-catenin. After long-term maintenance in two- and three-dimensional culture systems, EndoPCs were able to differentiate into liver-restricted lineages such as hepatocyte-like cells and bile duct-like structures in vitro and in vivo. After intra-muscular injection, EndoPCs generated macroscopically visible and well-vascularized liver-like tissue, which contained Alb+ liver parenchyma-like structures and substantial, KRT7/KRT19+ bile duct-like cell organizations. ConclusionWe have developed an efficient method for producing LGR5+ adult endodermal stem cells. These cells will be useful for the in vitro study of the molecular mechanisms of liver development and have important potential for therapeutic strategies, including approaches based on bioengineered liver tissue. These cells also open up new avenues for experiments focused on disease modeling, toxicology studies, and regenerative medicine applications.

developmental biology↗

bioRxiv2020

Pharmacologically modified pluripotent stem cell-based cancer vaccines with anti-metastatic potential

Cancer is maintained by the activity of a rare population of self-renewing "cancer stem cells" (CSCs), which are resistant to conventional therapies. CSCs share several antigenic determinants with pluripotent stem cells (PSCs). We show here that PSCs, combined with a histone deacetylase inhibitor (HDACi), are able to elicit major anti-tumor responses in a model of highly aggressive breast cancer. This immunotherapy strategy was effective in preventing tumor establishment and efficiently targeted CSCs by inducing extensive modifications of the tumor microenvironment. The anti-tumor effect was correlated with a reduction in regulatory T and myeloid-derived suppressor cell populations and an increase in cytotoxic CD8+T cells within the tumor and the spleen along with a drastic reduction in metastatic dissemination and an improvement in the survival rate. These results demonstrate for the first time the possibility of using PSCs and HDACi as an allogeneic anticancer vaccine, in future universal immunotherapy strategies.

cancer biology↗

bioRxiv2019

iPSC-derived Cancer Organoids Recapitulate Genomic and Phenotypic Alterations of c-met-mutated Hereditary Kidney Cancer

Hereditary cancers with cancer-predisposing mutations represent unique models of human oncogenesis as a driving oncogenic event is present in germline, exposing the healthy member of a family to the occurrence of cancer. The study of the secondary events in a tissue-specific manner is now possible by the induced pluripotent stem cell (iPSC) technology offering the possibility to generate an unlimited source of cells that can be induced to differentiate towards a tissue at risk of malignant transformation. We report here for the first time, the generation of a c-met-mutated iPSC lines from the somatic cells of a patient with type 1 papillary renal cell carcinoma (PRCC). We demonstrate the feasibility of kidney differentiation with iPSC-derived organoids expressing markers of kidney progenitors with presence of tight junctions and brush borders in tubular structures at transmission electron microscopy. Importantly, c-met-mutated kidney organoids expressed PRCC markers both in vitro and in vivo in NSG mice. Gene expression profiling of c-met-mutated iPSC-derived organoid structures showed striking molecular similarities with signatures found in a large cohort of PRCC patient samples and identified 11 common genes. Among these, BHLHE40 and KDM4C, well-known factors involved in PRCC pathogenesis, were expressed in c-met-mutated kidney organoids. This analysis applied to primary cancers with and without c-met mutation showed overexpression of the BHLHE40 and KDM4C only in the c-met-mutated PRCC tumors, as predicted by c-met-mutated organoid transcriptome. These data represent therefore the first proof of concept of the generation of \"renal carcinoma in a dish\" model using c-met-mutated iPSC-derived organoids, opening new perspectives for discovery of novel potentially predictive disease markers and novel drugs for future precision medicine strategies.

cancer biology↗