Chemotactic signaling and beyond： link between interleukin-16 and axonal degeneration in multiple sclerosis

Multiple sclerosis（MS）is a progressive inflammatory,and chronic demyelinating,neurodegenerative disease of central nervous system（CNS）.Autoimmune responses to myelin and other CNS antigens mediated by cluster of differentiation 4（CD4＋）T cells are critical for initiation and progression of disease.Migration of autoimmune T cells from the peripheral lymph organs into CNS parenchyma leads to inflammation,demyelination and damage of axonal cytoskeleton, which manifest in decreased impulse conduction velocity of motor and sensory nerves. Myelin and axonal pathology causes motor, sensory and autonomic nerve dysfunction, including optic nerve damage leading to double or distorted vision; paresis and paralysis of extremities, painful sensations, and bladder sphincter dysfunction, manifested as bladder incontinence. Gray matter pa- thology in cortical and subcortical regions, including cerebellum and hippocampus underlies cognitive and behavioral dysfunction consisting of memory deficits, depression, and ataxic gait and tremor.