Integrative Single-Cell and Spatial Transcriptomics Reveal Functional and Spatial Heterogeneity of Atrial and...

Area of Science:

• Cardiovascular Biology
• Molecular Cardiology
• Genomics

Background:

• Cardiomyocytes are crucial for heart function, with distinct atrial (aCM) and ventricular (vCM) subtypes.
• Understanding cardiomyocyte heterogeneity and communication is key to cardiac health.
• Single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics offer powerful tools for cardiac research.

Purpose of the Study:

• To map the spatial distribution of aCM and vCM subtypes within cardiac tissue.
• To investigate intercellular communication networks between cardiomyocyte subtypes.
• To correlate spatial organization with cardiomyocyte functions like energy metabolism and pump activity.

Main Methods:

• Isolation and scRNA-seq of cardiac cells for subtyping.
• Ligand-receptor interaction analysis to predict cell communication.
• Projection of scRNA-seq data onto heart tissue sections using spatial transcriptomics.

Main Results:

• Distinct spatial segregation of aCM and vCM subclusters was observed.
• Fibroblast populations were more concentrated near atrial regions.
• Key signaling pathways (e.g., Igf2-Igf2r, Vegfb-Vegfr1) mediated communication between cardiomyocyte subtypes.

Conclusions:

• Integrated scRNA-seq and spatial transcriptomics provide a detailed map of cardiac tissue organization.
• vCM are critical for energy metabolism and pump function, while aCM regulate blood flow and electrical conduction.
• This spatial context enhances understanding of cardiac function and identifies potential therapeutic targets for heart disease.