A World of Wonders: Interleukin-1 (IL-1) and IL-2 Families

Abstract

Human interleukins (ILs) are a collection of different biological molecules belonging to the group of cytokines, associated with various immune and non-immune systems and different signaling pathways. ILs contribute to the function of different tissues, organs and systems in the human body. They are involved in homeostasis, infectious diseases, autoimmune diseases, cancers and even therapeutics. Due to this knowledge, this chapter aims to summarize the importance of the IL-1 and IL-2 superfamilies.

The Interleukin-1 (IL-1) Superfamily Cytokines and Their Single Nucleotide Polymorphisms (SNPs)

“…These low molecular weight nonstructural proteins (5-20 kDa) are secreted by a number of subpopulations of immune cells, such as macrophages (M Φ s), neutrophils, natural killer (NK) cells, and T cells. These immune cells are involved in regulation, modulation, and promotion of immune responses by orchestrating cytokine-mediated activation, proliferation, development, differentiation, and growth among others [ 2 – 8 ], together with nonimmune, hemopoietic. and nonhemopoietic cells.…”

“…This term was suggested in 1979 during the 2 nd International Workshop of Lymphokines, which was held in Switzerland. The term interleukin was accepted by the cytokinologists, and this new term was officially published by the Journal of Cellular Immunology in the format of a letter to the editor [ 2 , 12 , 18 ].…”

“…ILs are identified as second messenger immune-glycoprotein biomolecules, encompassing a portion of mammals' cytokines [ 2 , 43 ]. Earlier, it was presumed that ILs were cytokines which were produced and secreted by leukocytes only; however, this thought has changed by the progression of our knowledge in this regard.…”

“…This domain is common and identical among TLRs and engagement of ILs binds them together as a unified structure [ 4 , 44 – 48 ]. On the other hand, ILs and TLRs are involved in homeostasis, cancers, and autoimmune and infectious diseases [ 2 , 6 , 10 , 47 , 48 ]. Because of the importance of IL biomolecules and their role in different parts of the human body, the occurrence of any mutation or polymorphism in their genes may results in a wide range of diseases and disorders.…”

“…As mentioned above, ILs are produced and secreted by a number of immune and nonimmune cells including M Φ s, monocytes, T (CD4+), and endothelial cells [ 2 , 3 ].…”