Introduction: Cytokines are usually soluble proteins that function in cell-to-cell communication. Originally identified as products of immune cells, cytokines can be produced by parenchymal cells as well. Although many serve endocrine functions, intracellular cytokines may exist in membrane-bound forms and exert reverse or paracrine signaling. They serve diverse biological functions ranging from cell death to survival and proliferation. Chemokines are special cytokines that show chemoattractant functions to recruit subtypes of leukocytes.
The blood-brain barrier restricts the permeation of peptides and polypeptide proteins (a category including cytokines and chemokines) from the circulation to the central nervous system, or vice versa. Certain cytokines can penetrate the blood-brain barrier by specific transport systems in the basal state.Prof Abba J. Kastin, Prof Weihong Pan describe the emerging understanding about the interaction between the brain and the immune system. For many years the brain was considered to be immunologically protected from the rest of the body’s defence and signalling molecules. It is now agreed that this is not so. Found on SciTopics
