Substances were selected based on how they protected nerve cells from damage
In progressive multiple sclerosis, the nervous system is what's being targeted by the disease. What happens is that a constantly elevated immune system will attack the nerves and damage neurons. This happens because iron is released while cells are damaged, which damages nerve cells even further. Researchers looked at the 249 different drugs by testing them in cell cultures inside the lab, to see which ones were able to protect nerves from the damaging effects of iron.