<unk> s <unk> s) are a group of cytokines (secreted proteins and signal molecules) that are expressed and secreted by white blood cells (leukocytes) as well as some other body cells. The human genome encodes more than 50<unk> s and related proteins. The function of the immune system primarily depends on<unk> s, and rare deficiencies of a number of them have been described, all featuring autoimmune diseases or immune deficiency. The majority of<unk> s are synthesized by CD4 helper T-lymphocyte, as well as through monocytes, macrophages, and endothelial cells. They promote the development and differentiation of T and B lymphocytes, and hematopoietic cells.<unk>  receptors on astrocytes in the hippocampus are also known to be involved in the development of spatial memories in mice.
Interleukin
Lymphokine
Cytokine
Defensin
Tumor necrosis factor
Histamine
Major basic protein
Leukotriene