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Fauriat, C.

Publications and source records attributed to Fauriat, C..

3 recordsLinked to original sources

Single Spectral Flow Cytometry Panel for Simultaneous Detection of Hematopoietic Stem, Progenitor, and Mature Lineages in Mouse Bone Marrow

Hematopoiesis occurs in the bone marrow of adult mammals and is supported by hematopoietic stem cells that sustain lifelong blood cell production. Pathological conditions can disrupt HSC differentiation, causing anaemia, immunodeficiency, and other cytopenias. Therefore, precise and simultaneous identification of hematopoietic populations from stem to mature cells is essential for understanding disease mechanisms and developing targeted therapies. In order to study these alterations, flow cytometry is generally a need-to-have monitoring technique. However, most cytometry panels are designed to thoroughly study a particular population, leaving out potential discoveries on other populations from the same microenvironment. Here we present the design of complex 19-marker spectral flow cytometry panel capable of simultaneously identifying HSPCs, erythroid, myeloid and lymphoid cells within a single murine BM sample. This integrated approach replaces multiple conventional panels and enables comprehensive mapping of hematopoietic differentiation from a single assay. Validation confirmed accurate detection of long-term and short-term HSCs, multipotent progenitors, common myeloid and lymphoid progenitors, and erythroid populations from proerythroblasts to reticulocytes. UMAP visualization captured the continuous trajectory of differentiation. We validated our method on aged and {beta}-thalassemic mouse models showing a clear detection of hematopoiesis and erythropoiesis alterations respectively. This panel provides a robust, flexible, and scalable platform suitable for both basic research and translational studies.

physiology↗

Downregulation of stromal syntenin sustains AML development

The crosstalk between cancer and stromal cells plays a critical role in tumor progression. Syntenin is a small scaffold protein involved in the regulation of intercellular communication that is emerging as a target for cancer therapy. Here, we show that certain aggressive forms of acute myeloid leukemia (AML) reduce the expression of syntenin in bone marrow stromal cells (BMSC), stromal syntenin deficiency, in turn, generating a pro-tumoral microenvironment. From serial transplantations in mice and co-culture experiments, we conclude that syntenin-deficient BMSC stimulate AML aggressiveness by promoting AML cell survival and protein synthesis. This pro-tumoral activity is supported by increased expression of endoglin, a classical marker of BMSC, which in trans stimulates AML translational activity. In short, our study reveals a vicious signaling loop potentially at the heart of AML-stroma crosstalk and unsuspected tumor-suppressive effects of syntenin that need to be considered during systemic targeting of syntenin in cancer therapy.

cancer biology↗

A syntenin-deficient microenvironment educates AML for aggressiveness

In acute myeloid leukemia (AML), the stromal microenvironment plays a prominent role in promoting tumor cell survival and progression. Although widely explored, the crosstalk between leukemic and stromal cells remains poorly understood. Syntenin, a multi-domain PDZ protein, controls both the trafficking and signaling of key molecules involved in intercellular communication. Therefore, we aimed to clarify the role of environmental syntenin in the progression of AML. By in vivo approaches in syngeneic mice, we demonstrate that a syntenin-deficient environment reprograms AML blasts to survive independently of the stroma. Up-regulation of EEF1A2 in the blasts controls this gain of cell survival. Furthermore, using ex vivo co-culture systems, we show that syntenin-deficient bone marrow stromal cells (BMSC) enhance the survival of different types of AML cells, including patient samples, and suffice to educate syngeneic AML, recapitulating micro-environmental effects observed in vivo. We establish that syntenin-deficiency causes an increase of eIF5A and autophagy-related factors in BMSC, and provide evidence that the inhibition of autophagy prevents syntenin-deficient BMSC to stimulate AML survival. Altogether, these findings indicate that host-syntenin in the BM microenvironment acts as a repressor of AML aggressiveness. Key points- A syntenin-deficient host reprograms AML blasts, enhancing total protein synthesis and cell survival pathways - Autophagy in the syntenin-deficient microenvironment is responsible for the gain of AML cell survival

cancer biology↗