10-15 minutes of sunshine or UVB phototherapy sends Treg cells flowing from the lymph nodes to sites of inflammation in people with MS. People with MS had symptom relief in a study completed by German neurologists and published last week.
Why the skin releases healing T cells when exposed to UV--Regulatory T cells (Tregs), which are induced locally in the skin-draining lymph nodes in response to UVB exposure, connect the cutaneous immune response to CNS immunity by migration to the sites of inflammation (blood, spleen, CNS). Here, they attenuate the inflammatory response and ameliorate disease symptoms.
as Dr. Richard Weller's research is showing is, it's thanks to nitric oxide.
http://ccsviinms.blogspot.com/2014/04/m ... mptom.html