Dissecting and Visualizing the Functional Diversity of Cardiac Macrophages

Megan Holt1, Julia Lin2,3, Markus Cicka1

  • 1Division of Cardiology, Department of Medicine, Center for Cardiovascular Research, Washington University School of Medicine (M.H., M.C., K.J.L.).

PubMed

Insights

Cardiac macrophages are diverse and play key roles in heart health and disease. New imaging techniques allow noninvasive tracking of these cells, paving the way for clinical applications.

Area of Science:

  • Cardiovascular Biology
  • Immunology
  • Cell Biology

Background:

  • Cardiac macrophages are crucial for heart homeostasis, repair, and remodeling.
  • Recent single-cell technologies reveal diverse macrophage subsets with distinct functions.
  • Understanding macrophage ontogeny (embryonic vs. adult progenitors) is key to their cardiac roles.

Purpose of the Study:

  • To elucidate the diversity and functional roles of cardiac macrophage subsets.
  • To highlight advancements in noninvasively detecting and measuring cardiac macrophages in vivo.
  • To explore the clinical translation potential of cardiac macrophage imaging.

Main Methods:

  • Single-cell technologies (transcriptional signatures, cell surface proteins).
  • Fate-mapping and parabiosis studies for macrophage ontogeny and dynamics.
  • Molecular tracers for noninvasive imaging (PET/CT, PET/MRI).

Main Results:

  • Identified distinct cardiac macrophage subsets derived from embryonic and adult progenitors.
  • Tissue-resident macrophages are protective, while monocyte-derived macrophages have context-dependent roles.
  • Noninvasive imaging enables serial visualization and measurement of cardiac macrophages in disease.

Conclusions:

  • Cardiac macrophages exhibit significant functional diversity influencing heart health and disease.
  • Noninvasive imaging of cardiac macrophages is advancing rapidly.
  • These advancements are critical for clinical translation and therapeutic strategies.

Related Concept Videos

Differentiation of Common Myeloid Progenitor Cells01:15

Differentiation of Common Myeloid Progenitor Cells

Common myeloid progenitors (CMPs) are oligopotent cells that can differentiate into granulocytes and macrophages. Granulocytes and macrophages are essential for protecting the body against bacterial, viral, or fungal infections. They migrate from the bone marrow into the circulating blood to reach specific tissue sites where they differentiate and help in immune surveillance. However, they survive only for a few days and must be continuously made available to the organism to maintain a robust...
3.2K
Structure of Cardiac Muscles01:13

Structure of Cardiac Muscles

Cardiac muscle, or myocardium, is a specialized type of muscle found exclusively in the heart. Its unique structural and functional characteristics enable the heart to perform its vital role of pumping blood throughout the body continuously and rhythmically. The cardiac muscle cells, or cardiomyocytes, possess an endomysium and perimysium but do not have an epimysium.
Compared to skeletal muscles, cardiac muscle cells are small and mostly have a single nucleus. Additionally, they are usually...
9.9K
Cell Diversity01:13

Cell Diversity

The concept of a cell started with microscopic observations of dead cork tissue by Robert Hooke in 1665. Hooke coined the term "cell" based on the resemblance of the small subdivisions in the cork to the rooms that monks inhabited, called cells. About ten years later, Antonie van Leeuwenhoek became the first person to observe the living and moving cells under a microscope. In the century that followed, the theory that cells represented the basic unit of life developed.
Multicellular...
3.2K
Specialized Characteristics of Cardiac Muscles01:27

Specialized Characteristics of Cardiac Muscles

The primary role of cardiac muscles is to propel blood throughout the cardiovascular system. The cardiac muscle cells, or cardiomyocytes, exhibit specialized characteristics that allow them to perform this function.
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy...
2.4K