Harmful and Beneficial Roles for the Adaptive Immune System in Neurodegenerative Conditions

To a first approximation, cells of the adaptive immune system are barred from the brain by the blood-brain barrier. This is only a first approximation, however, and more careful research has shown that a small number of adaptive immune cells do in fact enter the brain. This appears to be the case throughout life, a part of the normal interaction between immune system and central nervous system. The presence of adaptive immune cells in the brain in later life is also thought to be pathological, however, the result of age-related dysfunction of the blood-brain barrier, allowing unwanted cells into the brain to cause harm. Neurodegenerative disease defines conditions in which there is progressive neuronal loss in the central nervous system (CNS), leading to either physical disability, cognitive deficits or both. Classical neurodegenerative diseases include Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). Aging is a major risk factor for neurodegenerative disease, and with a growing elderly population, its prevalence is continuously increasing. Beyond being a risk factor, aging also increases the severity of disease and results in an impaired recovery following insult. Although these diseases have different pathogenetic mechanisms such as protein aggregation, demyelination, ischaemia, or direct trauma, they all share a hallmark of neuroinflammation. The immune system plays a key role in CNS homeostasis and disease. The i...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs