Table 2.

Comparison between adaptive immune cells in OAI and AAI.

Adaptive immune cells	Obesity	Aging
B cells
- B2	↑ accumulation of B cells (138) - ↑ class switched mature IgG+ B2 cells [M] (138) - Distinct IgG autoantibodies [H/M] (138, 141)- ↑ antigen presentation to T cells [M] (138) - ↑ pro-inflammatory cytokines [M] (138, 141)	↑ mature B2 in VAT [M] (147) ↑ circulating IgG levels [M] (147) ↑ OcaB expression in VAT [M] (147)
- B1	↓ frequency in B1a cells [M] (136) ↓ IL-10 production [M] (136) ↓ Breg functionality [M] (135)	↔↑ numbers of B1a and B1b [M] (147) ↑ accumulation of 4-1BBL+ B1a cells [H/M] (148)
- ABCs	Unclear if present in obesity independent of aging (154)	↑ in aging [H/M] (149–153) ↑ in females [M] (149) ↑ accumulation of aged adipose B cells (AABs) [M] (60, 156)
T cells	↑ in VAT [H/M] (157, 168–170)	x
CD4+	↑ in VAT [H/M] (157, 168–170)	↑ in VAT [M] (58)
- Th1	↑ Th1 polarization in CD4+ T cells [H/M] (157, 169, 170) ↑ production of IFNγ [H/M] (157, 169, 170)	x
- Th17	↑ accumulation in VAT [H/M] (157, 170, 172, 173) ↑ expression of Th17 markers (RORC/RORγt, IL-17, IL-23R) [H/M] (172, 173)	x
- Treg	↓ population in VAT [H/M] (157, 176)	↑ in VAT [M] (58, 111) ↑ enrichment in males [M] (111, 166, 186)
CD8+	↑ population in VAT [H/M] (167, 178) ↑ IFNγ secretion [H/M] (167, 178)	↑ in VAT [M] (58, 111) ↑ activation and pro-inflammatory cytokine secretion in females [M] (186)
ILTs
- iNKT	↓ population in VAT [H/M] (190, 203, 204)	x
- dNKT	↑ protection against metabolic disease [M] (206)	x
- γδ T cells	x	x
- MAIT cells	↑ frequency [H] (202, 208, 209) ↑ production of IL-17 [H] (210) ↓ production of IL-10 [H] (210)	x

A table of summary for the changes in adaptive 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.