Understanding the maintenance and regulation of HSCs in spleen by niche cells

ABSTRACT: Recent years have seen exploration into the hematopoietic stem cell (HSC) niche in adult bone marrow (BM). Due to their relatively rare occurrence, research on splenic HSCs and their role in hematopoiesis under steady-state conditions has been limited. However, studies have been taken up to understand extramedullary hematopoiesis (EMH) in spleen under stress and pathological conditions. Moreover, activation of EMH also has been linked to mobilized BM derived HSCs, and contribution from the splenic HSCs has not been clear. Our studies have identified a myofibroblastic niche in spleen that supports HSCs under homeostatic conditions. To assess the maintenance and regulation of HSCs in spleen tissue by niche cells, we performed label-free mass spectrometry (MS) based quantitative proteomic analysis. The splenic HSC niche cells including capsular and trabecular myofibroblasts (or CTMs/TBs), Lin-CD45- stromal cell population (or STs) and HSPCs (Lin-CD45+c-kit+Sca-1+) were isolated by fluorescence-activated cell sorting (FACS). The sorted cells were then lysed in lysis buffer, sonicated, thermally denatured, reduced, alkylated and tryptic digests were processed, desalted and analyzed on nano-LC coupled with high resolution mass spectrometer. Using Proteome Discoverer program and computational analysis performed on the global protein expression we examined the protein-protein interactions, cell-cell interactions and molecular pathways enriched in each cell population. This study demonstrates the molecular components HSC niche and presents a model to uncover novel hematopoietic regulators crucial for improving the function of adult and pluripotent stem cell derived HSCs.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Mus Musculus (ncbitaxon:10090)

SUBMITTER: Dr. Satish Khurana  

PROVIDER: MSV000095385 | MassIVE | Thu Jul 18 22:29:00 BST 2024

SECONDARY ACCESSION(S): PXD054056

REPOSITORIES: MassIVE