Immune Heterogeneity Now Sits at the Center of Atherosclerosis Biology
Atherosclerotic cardiovascular disease remains a major cause of death worldwide, but the modern view of the disease no longer stops at cholesterol deposition alone. This review places atherosclerosis inside a chronic inflammatory framework, where immune-cell diversity helps determine whether a plaque remains contained or progresses toward rupture and thrombosis. The emphasis is not on fixed cell labels. It is on function, adaptation, and the way immune populations shift as lesions evolve.
The central argument is straightforward: immune cells inside the arterial wall are not interchangeable. Macrophages, T cells, B cells, and innate immune subsets each occupy different roles across lesion initiation, necrotic core expansion, fibrous cap weakening, and thrombotic complications. In practical terms, plaque biology changes because the immune microenvironment changes first. Lipid accumulation triggers immune activation, but the resulting inflammatory network then feeds back on lipid handling, cell death, and tissue repair.
A single sentence captures the clinical tension. Plaques do not fail all at once; they become more dangerous as immune imbalance deepens.
Macrophage Plasticity, Cell Crosstalk, and the Road to Plaque Vulnerability
Among the immune populations discussed, macrophages receive the most attention because their functional range is unusually broad. Rather than remaining static scavenger cells, macrophages undergo continuous phenotypic shifts as the lesion matures. Some states favor lipid uptake and storage, while others are more closely tied to inflammatory amplification, defective efferocytosis, and tissue remodeling. These transitions matter because lipid-handling failure and impaired clearance of apoptotic cells allow the necrotic core to enlarge, a step that makes plaques structurally less stable.
The review links this process to the broader immune microenvironment rather than to one cell type in isolation. Cellular crosstalk shapes plaque behavior at every stage. Macrophages interact with T cells, B cells, endothelial cells, and other innate immune elements through molecular signals that can amplify inflammation or restrain it. When these circuits remain balanced, the artery wall can partially contain injury. When they break down, inflammatory persistence accelerates matrix degradation and fibrous cap weakening.
Single-cell transcriptomics has sharpened this picture by revealing immune diversity that older bulk methods could not resolve. Instead of treating plaque macrophages or lymphocytes as uniform groups, transcriptomic profiling shows multiple functional states coexisting in the same lesion. Some subsets appear specialized for lipid handling, others for immune activation, and still others for responses that may vary depending on local cues. This finer-resolution view supports a more realistic understanding of why two plaques that look similar by standard imaging can behave differently biologically.
The biology also explains why clearance of apoptotic cells is so important. If dying cells are not efficiently removed, cellular debris accumulates, inflammation persists, and the core becomes increasingly necrotic. That sequence contributes directly to plaque instability. In arterial disease, failure of cleanup is not a minor housekeeping defect; it is a structural hazard.
T Cells, B Cells, Innate Subsets, and Territory-Specific Immune Signals
The review extends beyond macrophages to examine the context-dependent roles of T-cell, B-cell, and innate immune subpopulations. These cells do not act in the same way across all vascular beds. Their phenotype can differ by territory, local hemodynamic stress, and lesion stage, creating spatiotemporal variation in immune activity across the arterial tree. A coronary plaque, a carotid plaque, and disease in another vascular region may therefore reflect different immune settings even when they share the same broad diagnosis.
This is one reason the review places such weight on dynamic classification. Atherosclerosis is not a single immune program replayed in every vessel. It is a series of overlapping local immune responses, each shaped by the surrounding molecular environment. Some immune subsets may support inflammation, while others may influence repair or tolerance. The same cell lineage can also behave differently depending on where it sits and which signals dominate its surroundings.
The role of immune checkpoints adds another layer of complexity. The review addresses the clinical implications of checkpoint regulation without overstating how far the field has already moved into routine cardiovascular care. In oncology, checkpoint pathways are established therapeutic targets. In atherosclerosis, the relevance is still being defined, and any translational move must account for the possibility that altering immune restraint could affect plaque inflammation in ways that are beneficial, harmful, or highly context-specific. The cardiovascular system does not offer the same therapeutic latitude as a tumor, because immune modulation here must preserve host defense while avoiding destabilization of a chronic lesion.
Local vascular territory also shapes immune behavior in ways that may influence risk. If immune networks vary across sites, then plaque biology cannot be fully understood by studying only one vascular bed. The review’s focus on spatiotemporal variation therefore has direct clinical significance: precision therapy will require lesion-specific thinking, not just disease-label thinking.
Precision Immunomodulation Is the Goal, but Translation Still Has Barriers
The review closes on a therapeutic premise that is compelling yet still incomplete. If immune heterogeneity helps drive plaque progression, then targeted immunomodulation could, in theory, alter the disease course more effectively than broad suppression. Precision therapy would aim to influence the most harmful immune states while preserving protective or reparative functions. That approach is attractive because it aligns treatment with plaque biology rather than with a one-size-fits-all inflammatory model.
Still, the barriers to clinical translation remain substantial. Immune pathways in atherosclerosis are interconnected, and manipulating one arm of the response may shift another in unpredictable ways. A therapy that reduces inflammatory signaling might also alter lipid handling, cell survival, or plaque remodeling. The review does not present a finished therapeutic algorithm. Instead, it frames a research agenda built on better cellular resolution, stronger mechanistic mapping, and careful attention to vascular context.
The most useful insight is also the simplest one. Precision immunotherapy in atherosclerosis will depend on knowing which immune state is present, where it is located, and how it changes over time. Without that level of detail, treatment risks being too broad for a disease that is biologically specific at every stage.
For now, the field is moving from static immune classification toward dynamic lesion biology. The next advance will not come from naming more cells alone. It will come from linking those cells to plaque behavior in a way that can be translated into safer cardiovascular therapies.