The aim of the study is to explore the relationship between leakage of the blood-brain barrier and inflammation, the reason why demyelination occurs--seemingly in the absence of an antigen-specific immune response that requires explanation if a coherent account of an inflammatory-mediated demyelination is to be achieved. In this study the cellular biology of the glial cells important for the synthesis and maintenance of central nervous system (CNS) myelin and their inter-relations with other environmental cells (neuronal, microglial, olygodendroglial, astrocytes, endothelial, epithelial, T lymphocytes, B lymphocytes, monocytes, and macrophages) and with the compound of the extracellular matrix (ECM) during the development of an autoimmune inflammatory and demyelinating processes in the brain was analyzed. Upon activation in the peripheral tissue, immune cells reach their target organ via bloodstream and interacting with blood vessels wall components in the absence of exogenous stimulus mount an attack against the local milleu, which is the starting point of a pathogenic inflammatory reaction. Each of these contacts may trigger profuse secretion of cytokines, chemokines, and other soluble inflammatory mediators, which in the CNS by activating of local glial cells and by attracting and stimulating blood-borne monocyte/macrophages can act directly on neural cells and will cause their demyelination.