A bone marrow stromal secretome screen identifies semaphorin 3A as a regulator of stress hematopoiesis
Ontology highlight
ABSTRACT: Bone marrow mesenchymal stromal cells (MSCs) are a major source of secreted factors that control hematopoietic stem and progenitor cell (HSPC) function. We previously reported the generation of revitalized MSCs (rMSCs), which support functional HSCs in culture more effectively than control MSCs. In a secretomic screen using rMSCs, we identified semaphorin 3A (SEM3A) as a secreted factor upregulated as part of a pro-inflammatory signature that may underly HSPC expansion by rMSCs. Similarly, SEM3A expression is upregulated by BM-MSCs in vivo in response to hematopoietic stress. Recombinant SEM3A directly promotes HSPC quiescence ex vivo. Analysis of a SEM3A loss of function mutation in vivo revealed hematopoietic progenitor expansion and accelerated recovery after myeloablation, consistent with a role for SEM3A in regulating the HSPC stress response. This work highlights proteomic screening using rMSCs as a method to identify novel secreted niche factors and uncovers a novel role for SEM3A in promoting HSPC quiescence in stress hematopoiesis.
INSTRUMENT(S): Orbitrap Fusion Lumos
ORGANISM(S): Mus Musculus (mouse)
TISSUE(S): Bone Marrow
SUBMITTER:
Simone Sidoli
LAB HEAD: Simone Sidoli
PROVIDER: PXD065232 | Pride | 2025-07-11
REPOSITORIES: Pride
ACCESS DATA