Table 1.
Comparison of the features of focal and disseminated brain inflammation
| Inflammation features | Focal brain inflammation | Disseminated brain inflammation |
|---|---|---|
| Initiating events | Damaged cells release DAMPs | Remote neural cell injury; vascular damage; diffuse axonal injury; CSF inflammation. |
| Dynamic change of components | ||
| Glia cells (microglia and astrocytes) | ||
| Initiation | Minutes after the initial injury | 1 week, after focal inflammation decreasesa |
| Persistence | Approximately 1 week | Increasingly progressive, lifelong |
| Myeloid cells (neutrophils and monocytes) | ||
| Initiation | Hours | Approximately 1 weeka |
| Persistence | Days | Lifelong |
| Lymphocytes | ||
| Initiation | Within 1 day | Within 1 daya |
| Persistence | Days to weeks | Lifelong, with a shift to B cell dominance in the chronic phase |
| Inflammatory mediators | ||
| Components | Many are involved, including TNF, IFNγ, IL‑1β, IL‑6, IL‑10, GM‑CSF, TGFβ, and CCL2. | Many are involved, including CXCL1, IL-13, CCL2, IL-9, IL-10, IL-17, and MIP-1α. |
| Dynamics | Most increase minutes to hours after the initial injury, peak at approximately 1 day, and then decrease over subsequent days. | Appears 1 day after injury, the spectrum changes with the progression of disease stages and persists for at least months. |
| Distribution | Within the lesion and surrounding tissue | Thalamus, hippocampus, pituitary, corpus callosum, occipital cortex, brain stem, and spinal cord. |
| Pathological effects | Detrimental: Edema and cell death in areas surrounding the lesion. Beneficial: Clearance of dead cells; preservation of barrier function. | Disturbance of specific functional regions, such as the thalamus and pituitary; chronic and progressive neurodegeneration. |
| Effects of inhibiting inflammation | Controversial | The impact on chronic brain inflammation may rescue chronic degeneration. |
DAMP damage-associated molecular pattern, CSF cerebrospinal fluid, TNF tumor necrosis factor, IFNγ interferon γ, IL interleukin, GM-CSF granulocyte-macrophage colony-stimulating factor, TGFβ transforming growth factor β, CCL2 C-C chemokine ligand 2, CXCL1 C-X-C chemokine ligand 1, MIP-1α macrophage inflammatory protein 1α
aThe time at which the cells begin to be detected in distal regions