Table 3.
Macrophage functions and the pathological consequences of their anomalous activation in the main tissues.
| Macrophages (MΦ) | Tissue | Functions | Pathology |
|---|---|---|---|
| Microglia | Brain | Brian development (121), immune surveillance, synaptic remodeling (122) | Neurodegeneration (123) |
| Osteoclasts | Bone | Bone modeling and remodeling, bone resorption (124), support to hematopoiesis (125) | Osteoporosis, osteopetrosis, arthritis (126) |
| Heart MΦ | Heart and vasculature | Surveillance | Atherosclerosis (127) |
| Kupffer cells | Liver | Toxin removal, lipid metabolism, iron recycling, erythrocyte clearance, clearance of microbes, and cell debris from blood (128, 129) | Fibrosis (130), impaired erythrocyte clearance (131) |
| Alveolar MΦ | Lung | Surfactant clearance, surveillance for inhaled pathogens (132) | Alveolar proteinosis (133) |
| Adipose tissue-associated MΦ | Adipose tissue | Metabolism, adipogenesis, adaptive thermogenesis (134) | Obesity, diabetes, insulin resistance, loss of adaptive thermogenesis (131) |
| Bone marrow MΦ | Bone marrow | Reservoir of monocytes, waste disposal (131) | Disruption of hematopoiesis (131) |
| Intestinal MΦ | Gut | Tolerance to microbiota, defense against pathogens, intestinal homeostasis (135) | Inflammatory bowel disease (136) |
| Langerhans cells | Skin | Immune surveillance (137) | Insufficient healing, fibrosis (138) |
| Marginal zone MΦ, red pulp MΦ | Spleen | Erythrocyte clearance, iron processing, capture of microbes from blood (139) | Impaired iron recycling and erythrocyte clearance (140) |
| Inflammatory MΦa | All tissues | Defense against pathogens, protection against dangerous stimuli (141) | Chronic inflammation, tissue damage, autoimmunity (91) |
| Healing MΦb | All tissues | Branched morphology, angiogenesis (142) | Cancer, fibrosis, epithelial hyperplasia (91) |
aAlso known as inflammatory macrophages or M1 macrophages.
bAlso known as deactivated or M2 macrophages.