Interleukin and interleukin receptor gene polymorphisms in inflammatory bowel diseases susceptibility

Table 1 Characteristics of cytokines in inflammatory bowel diseases

Family	Cytokine	Receptor	Cytogenetic location	Molecular weight	Cell source	Disease association (IBD)
IL1	IL1A	IL1R1	2q14	17 kD	Macrophages, monocytes, lymphocytes, keratinocytes, microglia, megakaryocytes, neutrophils, fibroblasts and synovial lining cells	CD, UC
	(IL1F1)	IL1R2
	IL1B	IL1R1	2q14	17 kD
	(IL1F2)	IL1R2				CD, UC
	IL1RN	IL1R1	2q14.2	16.1-20 kD	Monocytes, macrophages, fibroblasts, neutrophils, epithelial cells and keratinocytes	UC
	(IL1F3)	IL1R2
	IL18	IL18R1	11q22.2-q22.3	22.3 kD	Macrophages, Kupffer cells, keratinocytes, osteoblasts, astrocytes, and DCs	CD, UC
	(IL1F4)	IL18RAP
IL2	IL2	IL2R	4q26-q27	15.5 kD	CD4+, CD8+ activated T cells, DCs, NK and NKT cells	CD, UC
	IL4	IL4RI	5q23-q31	15 kD	Th2 cells, basophils, eosinophils, mast cells, NKT and γ/δ T cells	CD
		IL4RII
	IL21	IL21R	4q26-q27	15 kD	T and NKT cells	CD, UC
IL10	IL10	IL10RA/IL10RB	1q31-q32	18.6 kD	T and B cells, monocytes, macrophages and DCs	CD, UC
	IL19	IL20RA/IL20RB	1q32.2	35-40 kD	Monocytes, keratinocytes, airway epithelial cells and B cells	UC
	IL26	IL10R2/IL20R1	12q15	38 kD	Activated T cells	CD, UC
IL12	IL12	IL12RB1/IL12RB2	5q33.3	IL12A: 35 kD, IL12B: 40 kD	Monocytes, macrophages, neutrophils, microglia, DCs and B cells	CD, UC
	IL23	IL12RB1/IL23R	12q13.13	19 kD	Macrophages and activated DCs	CD, UC
	IL27	IL27RA/ IL6ST	16p11	IL27A: 2 8 kDIL27B: 25.4 kD	Activated DCs, macrophages, and epithelial cells	CD, UC
IL6-like cytokines	IL6	IL6R/IL6ST	7p21-p15	19-26 kD	Endothelial cells, fibroblasts, monocytes/macrophages	CD
IL17	IL17A	IL17RA/ IL17RC	6p12	35 kD	Th17, CD8+ T cells, NK cells, NKT cells, γ/δ T cells and neutrophils	UC
	IL17F	IL17RA/IL17RC	6p12	44 kD	Th17, CD8+ T cells, NK cells, NKT cells, γ/δ T cells and neutrophils	CD, UC
Chemokines	IL8	IL8RA/IL8RB	4q13-q21	16 kD	Monocytes, macrophages, neutrophils, lymphocytes, endothelial cells, epithelial cells, fibroblasts, keratinocytes, chondrocytes, synovial cells, and hepatocytes	CD, UC
	IL16	CD4	15q26.3	56 kD	T cells, eosinophils, mast cells, eosinophils, monocytes, DCs, fibroblasts and epithelial cells	CD
Th2-like cytokines	IL13	IL13RA1/IL13RA2	5q31	10 kD	T, NKT, mast cells, basophils and eosinophils	CD, UC

IBD: Inflammatory bowel disease; CD: Crohn’s disease; UC: Ulcerative colitis; NK: Natural killer cells; NKT: Natural killer T cells; DCs: Dendritic cells.