Table 1.

Distinct effects of leptin across immune cell types.

Immune cell	Leptin Effect
CD4+ T cells	Required for T cell development in the thymus (31–34) Increases proliferation of naïve T cells (35, 36) Promotes Th1 cytokine production (35) Promotes Th17 differentiation and cytokine production (34) Promotes increased glycolytic metabolism (31, 34)
B cells	Reduces apoptosis (37) Promotes cell cycle entry (37) Increases inflammatory cytokine production (38) Reduces class switching and IgG production (38)
Macrophages	Promotes bacterial clearance and phagocytosis (39, 40)
Monocytes	Increases TLR2 expression (41) Promotes inflammatory cytokine production (42)
Mast Cells	Promotes mast cell phenotype that drives inflammatory M1-like macrophage cell phenotype (43)
Dendritic cells	Reduces apoptosis by increasing expression of Bcl-2 and Bcl-xL (44) Promotes DC maturation and function (45) Increases inflammatory cytokine production (44)
Neutrophils	Inhibits apoptosis (46) Acts as chemoattractant (22, 47) Increases oxidative species production (48)
Basophils	Inhibits apoptosis (49, 50) Acts as chemoattractant, promotes trafficking toward other chemo attractants such as eotaxin (49) Increases IL-4 and IL-13 production (49)
Eosinophils	Inhibits apoptosis (49, 50) Acts as chemoattractant, promotes trafficking toward other chemo attractants such as eotaxin (51)
NK cells	Brief exposure promotes increased cytotoxicity (52) 18-h exposure increases IFN-γ and perforin production (52, 53) 72-h exposure inhibits IFN-γ and cytotoxicity (52)
ILCs	Promotes type-2 cytokine production (54)