| IL-1β |
Pro-inflammatory; induces fever, acute phase protein
production, activation of endothelial cells; recruits immune
cells. |
Macrophages, monocytes, dendritic cells, epithelial cells |
Endothelial cells, hepatocytes, T cells, hypothalamic
cells |
Involved in sepsis, rheumatoid arthritis, IBD, gout.
Targeted by Anakinra (IL-1 receptor antagonist). |
| IL-2 |
T cell growth factor; promotes differentiation and
survival of T cells (especially regulatory T cells);
activates NK cells. |
Activated CD4+ T cells (especially Th1), CD8+ T cells |
T cells, NK cells |
Important in autoimmune diseases; used in cancer
immunotherapy (high-dose IL-2 stimulates anti-tumor T
cells). |
| IL-4 |
Promotes Th2 differentiation; stimulates IgE production;
promotes B cell growth and differentiation;
anti-inflammatory effects. |
Th2 cells, mast cells, basophils, eosinophils |
B cells, T cells, macrophages, endothelial cells |
Allergic diseases (asthma, atopic dermatitis), parasitic
infections. Targeted by Dupilumab. |
| IL-5 |
Promotes eosinophil differentiation, activation, and
survival. |
Th2 cells, mast cells |
Primarily eosinophils; minor effects on B cells |
Eosinophilic diseases (asthma, eosinophilic esophagitis),
parasitic infections. Targeted by Mepolizumab and
Reslizumab. |
| IL-6 |
Pro-inflammatory; induces acute phase protein production;
promotes B cell differentiation; stimulates antibody
production. |
Macrophages, T cells, fibroblasts, endothelial cells |
Hepatocytes, B cells, T cells |
Involved in rheumatoid arthritis, SLE, cytokine release
syndrome. Targeted by Tocilizumab and Sarilumab. |
| IL-10 |
Anti-inflammatory; inhibits cytokine production by
macrophages and dendritic cells; suppresses T cell
proliferation. |
Regulatory T cells (Tregs), macrophages, B cells |
T cells, B cells, macrophages, dendritic cells |
Maintains immune tolerance; potential target in IBD and
autoimmune diseases. |
| IL-12 |
Promotes Th1 differentiation; activates NK cells; enhances
cytotoxic T cell activity; stimulates IFN-γ production. |
Dendritic cells, macrophages |
T cells, NK cells |
Important in immunity against intracellular pathogens;
involved in autoimmune diseases (e.g., psoriasis). |
| IL-13 |
Promotes IgE production; induces airway hyperreactivity;
increases mucus production; promotes fibrosis; promotes
alternative (M2) macrophage activation; induces eotaxin-3
production. |
Th2 cells, mast cells, basophils, innate lymphoid cells
(ILCs) |
B cells, epithelial cells, smooth muscle cells,
macrophages |
Allergic diseases (asthma, atopic dermatitis, eosinophilic
esophagitis), parasitic infections. Targeted by Dupilumab. |
| IL-17A |
Pro-inflammatory; recruits neutrophils; promotes
production of other cytokines; involved in barrier immunity. |
Th17 cells, innate lymphoid cells (ILCs) |
Neutrophils, epithelial cells, fibroblasts |
Involved in psoriasis, rheumatoid arthritis, ankylosing
spondylitis, IBD. Targeted by Secukinumab, Ixekizumab,
Brodalumab. |
| IL-18 |
Promotes IFN-γ production; enhances NK and T cell
activity; synergizes with IL-12 in Th1 responses. |
Macrophages, dendritic cells |
NK cells, T cells |
Involved in autoimmune diseases, sepsis, and metabolic
disorders; potential target in inflammatory conditions. |
| IL-21 |
Regulates B cell differentiation and antibody production;
promotes Th17 responses; enhances cytotoxic T cell and NK
cell function. |
Activated CD4+ T cells (especially T follicular helper
cells) |
B cells, T cells, NK cells |
Involved in autoimmune diseases (e.g., lupus), cancer
immunotherapy, chronic viral infections. |
| IL-23 |
Promotes Th17 cell survival and expansion; involved in
chronic inflammation. |
Dendritic cells, macrophages |
Th17 cells, innate lymphoid cells (ILCs) |
Involved in psoriasis, IBD, ankylosing spondylitis.
Targeted by Risankizumab, Guselkumab, Tildrakizumab. |
| IL-33 |
Alarm cytokine released from damaged cells; activates
innate immune cells; promotes Th2 responses. |
Epithelial cells, endothelial cells, fibroblasts |
Mast cells, innate lymphoid cells (ILC2s), Th2 cells |
Allergic diseases (asthma, atopic dermatitis),
inflammatory diseases. |