ARG1 and stroke disorder: Looking at the proportional contribution of the iNOS+ and Arg1+ subsets to the total number of activated CD68+ microglia/macrophages, more than 90% of CD68+ cells were Arg1+ in the early stages after stroke; however, these numbers decreased substantially by day 4, where they constitute ≈55% of all activated microglia/macrophages (Fig 2C).