Contrary to the knowledge that ILC3 cells usually help the immune system tolerate beneficial microbes and suppress inflammation in the intestines and other organs, a recent study has found that a group of immune cells among the group 3 innate lymphoid cells (ILC3s) might be responsible for inflammation in multiple sclerosis (MS) and other brain inflammation-related conditions. The study, initiated by Weill Cornell Medicine and NewYork-Presbyterian researchers, also found this group of cells circulating in the bloodstream and infiltrating the brain and not quenching the inflammation but instead igniting it, leading to a condition modelling MS. The researchers pointed out that countering the activity of these cells could be a new therapeutic approach for such conditions.