A receptor may hold key to multiple sclerosis treatment

14-06-2012: A receptor recently discovered to control the movement of immune cells across central nervous system barriers (including the blood-brain barrier) may hold the key to treating multiple sclerosis (MS).

In MS, immune cells enter the central nervous system and attack and destroy the myelin sheath surrounding the axons of nerve cells in the brain and spinal cord, resulting in blindness, paralysis, incontinence and many more symptoms.

The research, appearing in the Journal of Immunology, reveals how the A2A adenosine receptor expressed on blood-brain barrier cells acts as a gateway, allowing immune cells to enter the brain, where they can cause havoc in people with MS.

The blood-brain barrier is composed of specialized cells that selectively prevent substances from passing from the bloodstream into the brain.

In this study, the researchers used mice where the A2A adenosine receptor was knocked out and then infused those mice with normal immune cells from wild-type mice expressing the A2A adenosine receptor. This produced chimeric mice expressing the A2A receptor on immune cells, but not on blood-brain barrier cells. Without A2A receptor on blood-brain barrier cells, the normal immune cells failed to effectively infiltrate the central nervous system, and thus, these mice were protected and developed less severe symptoms of MS-like disease.