Table 1.
Concentrations [pg mL−1] in different in vitro body fluids | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Cytokines | Cytokine type | Cell sources | Half life | Biological functions | Serum | Plasma | Saliva | Tears | Stool | References |
IL‐1β | Pro‐inflammatory | Monocytes/macrophages | 21 min | Principal mediator of the systemic effects of IL‐1; it affects IL‐6‐induced gene expression | – | 1.5 ± 1.2 | 1.5–5.3 × 102 | 102 ± 2.8 | – | [ 207 , 208 , 209 , 210 , 211 , 212 ] |
IL‐6 | Pro‐ and anti‐inflammatory | B and T cells, monocytes, fibroblasts, endothelial cells, and some tumor cells | 15.5 h |
Inducer of the acute‐phase response as well as specific cellular and humoral immune responses. Inhibition of TNF and IL‐1 production by macrophages |
8.5–14 | 22 ± 8.6 | 0–27 | 1.3 × 102 ± 12 | 0.3 ± 0.1 | [ 207 , 208 , 209 , 212 , 213 , 214 , 215 , 216 ] |
IL‐8 | Pro‐inflammatory | Monocytes, macrophages, endothelial cells, epithelial cells, hepatocytes, chondrocytes, and tumor cells | 24 min | Pro‐inflammatory mediators that orchestrate the recruitment of leukocytes to sites of inflammation | 24–36 | 9.4 ± 3.7 | 0.4–3.2 × 102 | – | – | [ 208 , 211 , 212 , 213 , 214 ] |
IL‐12 | Pro‐inflammatory | Phagocytic cells, microglial and dendritic cells | – | Th cell differentiation, TNF‐α, IFN‐γ synthesis | 20–56 | 1.2 × 102 ± 8.6 | 0–7.6 | 47 | – | [ 90 , 208 , 209 , 212 , 213 ] |
TNF‐α | Pro‐inflammatory | Macrophages, mast cells, NK cells, VSMCs, T‐ and B‐cells | 18.2 min | Pro‐inflammatory, neutrophil activation, bone resorption, anticoagulant, tumor necrosis, activate and increase permeability, stimulate adhesion molecules | 28–38 | 5.9 ± 0.4 | 0–5.8 | 48 ± 3.3 | 1.8 ± 0.3 | [ 6 , 91 , 207 , 208 , 209 , 212 , 213 , 216 ] |
IFN‐γ | Pro‐inflammatory | Macrophages, Th1 cells, Tc cells, B‐cells, Natural killer (NK) cells, VSMCs | – | Pro‐inflammatory, promotes Th1 immune responses/secretion of Th1‐associated cytokines, inhibits ECM synthesis by SMC MHC I expression | (1.2–1.6) × 102 | 7 ± 2.5 | 0–7 | 42 ± 3.6 | 0.4 ± 0.2 | [ 6 , 208 , 209 , 212 , 213 , 216 ] |
IL‐1RA | Anti‐inflammatory | Monocytes/macrophages, dendritic cells | 4–6 h | Inhibition of IL‐1α‐ and IL‐1β‐mediated cellular activation at the IL‐1 cellular receptor level | (1–1.7) × 102 | 50 ± 21 | – | (3.9 ± 0.9) × 103 | – | [ 67 , 208 , 209 , 213 , 217 ] |
IL‐4 | Anti‐inflammatory | T cells (Th2), mast cells, B cells, stromal cells | 20 min | Promotes Th2 lymphocyte development; inhibition of LPS‐induced proinflammatory cytokine synthesis | 6.9–8.1 | (2.3 ± 0.5) × 102 | – | 21 ± 1.6 | – | [ 67 , 207 , 208 , 209 , 213 , 218 ] |
IL‐10 | Anti‐inflammatory | Monocytes/macrophages, T cells (Th2), B cells | – | Inhibition of monocyte/macrophage and neutrophil cytokine production and inhibition of Th1‐type lymphocyte responses | 8.5–17 | 38 ± 2.1 | 0–10 | 37 ± 0.9 | – | [ 67 , 208 , 209 , 212 , 213 ] |
IL‐11 | Anti‐inflammatory | Stromal cells, fibroblasts | – | Inhibits proinflammatory cytokine response by monocytes/macrophages and promotes Th2 lymphocyte response | – | – | – | – | – | [ 67 ] |
IL‐13 | Anti‐inflammatory | T cells (Th2) | – | Shares homology with IL‐4 and shares the IL‐4 receptor; attenuation of monocyte/macrophage function | 11–18 | (1.1 ± 0.2) × 102 | – | 47 ± 3.2 | – | [ 67 , 208 , 209 , 213 ] |