Table 1.
Comparison between innate immune cells in OAI and AAI.
| Innate immune cells | Obesity | Aging |
|---|---|---|
| Macrophages | ↑ in ATM population [H/M] (33–35, 39–43) ↑ pro-inflammatory cytokine release [H/M] (33–35, 39–43) ↑ inflammatory cross-talk [H/M] (33–35, 39–43) ↑ crown-like structures [H/M] (44–47) ↑ in pro-inflammatory CD9+ macrophages (LAMs) [H/M] (54) |
↑ pro-inflammatory phenotype [M] (58) ↓ proportion of M2-like ATMs [M] (58) ↔ proportion of M1-like ATMs [M] (58) ↑ proportion of CD11c- CD206- ATMs [M] (58) ↑ expression of CCR2, IL-6, MCP-1, TNFα [M] (58) ↓ expression of PPARγ [M] (58) |
| ILCs | ||
| - ILC-1 | ↑ proportion in early obesity [H/M] (64, 65) ↓ proportion in chronic obesity [H/M] (64, 65) ↑ IFNγ and TNFα secretion [H/M] (65, 74, 76, 77) ↑ mNK recruitment and expansion [H/M] (64, 65) ↓ in NK degranulation and pro-inflammatory cytokine production during chronic obesity [H/M] (79) ↑ myNK expansion in chronic obesity [H/M] (80) |
↔ proportion [H] (62) |
| - ILC-2 | ↓ frequency in WAT [H/M] (68) | ↔ proportion [H] (62) |
| - ILC-3 | x | ↔ proportion [H] (62) |
| Neutrophils | ↑ frequency [H/M] (85, 89) ↑ activation [H/M] (85, 89) ↑ production of elastase [M] (85) ↑ release and ↓ clearance of NETs [M] (86) |
x |
| DCs | ||
| - cDCs | ↓ anti-inflammatory profile [M] (10) ↑ accumulation of VAT cDCs [H/M] (101, 102) ↑ promotion of Th17 cell responses [H/M] (53) |
x |
| - pDCs | ↑ recruitment to VAT [H/M] (103–105) ↑ IFN-1 signaling in VAT and polarization of ATMs to M1-like state [H/M] (103–105) |
x |
| Eosinophils | ↓ eosinophils in VAT [M] (108) | ↔↓ eosinophils in VAT [M] (111) |
| Mast Cells | ↑ mast cells in VAT [H/M] (114, 116, 117) ↑ inflammation of VAT endothelium, ATM accumulation, formation of fibrous tissue [H] (117) |
x |
| MDSCs | ↑ MDSCs in VAT [M] (128) ↑ protection against metabolic disease [M] (129) |
x |
A table of summary for the changes in innate immune cell populations specifically within the adipose tissue in obesity and aging.
“x” indicates studies are lacking.
↑ indicates increased, ↓ indicates decreased, and ↔ indicates no change or no consensus.
[H/M] indicates data seen in human and/or mouse studies.