Spatial transcriptomics of murine bone marrow megakaryocytes at single-cell resolution

Area of Science:

• Hematology
• Molecular Biology
• Spatial Biology

Background:

• Megakaryocytes are known for platelet production but possess uncharacterized subpopulations with immunoregulatory roles.
• Single-cell RNA sequencing suggests transcriptional variation in megakaryocytes, but their spatial organization and regulation remain unclear.
• Bone marrow complexity necessitates spatial transcriptomic approaches to understand megakaryocyte heterogeneity.

Purpose of the Study:

• To integrate spatial context with transcriptomics for single-cell level analysis of murine bone marrow megakaryocyte heterogeneity.
• To investigate the spatial distribution and transcriptional profiles of megakaryocytes within the bone marrow niche.

Main Methods:

• Bone marrow sections from C57BL/6J mice femurs were analyzed.
• Nanostring GeoMx digital spatial profiling platform used for murine whole transcriptome array.
• 44 CD41+ megakaryocytes profiled in situ for spatial transcriptomic analysis.

Main Results:

• No association found between megakaryocyte transcriptomic profile and vascular adjacency.
• Significant differences in gene expression observed between proximal and distal bone marrow regions.
• Genes linked to platelet production (proplatelet basic protein, platelet factor 4) showed higher expression in proximal megakaryocytes.

Conclusions:

• Spatial location influences megakaryocyte heterogeneity within the bone marrow.
• Further investigation into megakaryocyte subpopulations is needed, considering their spatial orientation.
• Findings suggest a role for bone marrow microenvironment in megakaryocyte differentiation and function.