Cytokine receptor
Cytokine receptors are receptors that bind to cytokines. In recent years, the cytokine receptors have come to demand the attention of more investigators than cytokines themselves, partly because of their remarkable characteristics, and partly because a deficiency of cytokine receptors has now been directly linked to certain debilitating immunodeficiency states. In this regard, and also because the redundancy and pleiotropy of cytokines are a consequence of their homologous receptors, many authorities are now of the opinion that a classification of cytokine receptors would be more clinically and experimentally useful. Classification. A classification of cytokine receptors based on their  three-dimensional structure has been attempted. (Such a classification, though seemingly cumbersome, provides several unique perspectives for attractive pharmacotherapeutic targets.) Solubility. Cytokine receptors may be both membrane-bound and soluble. "Soluble cytokine receptors" are extremely common regulators of cytokine function. Soluble cytokine receptors typically consist of the extracellular portions of membrane-bound receptors. .