@LegakisL Good question. For astrocytes, you can use GFAP. See the Antibody Database for good GFAP antibodies. For microglia, Iba1 is typically used, as you say, and in addition to the most popular rabbit Iba1 ab from Wako, @tberta also has found a good one from Abcam made in goat (see Database). Ox42 is also used for microglia, but I haven’t used it myself. Anti-CD68 from Ab Serotec is quite good. I use at a concentration of 1:1000 for macrophages in the DRG and nerve tissue. You could try in the spinal cord too, since CD68 is thought of as a marker of activated macrophages/microglia, even though resting state cells also have. @tberta knows a lot about glial activation, so hopefully he can chime in.
I haven’t used an iNOS antibody for M1/M2 transition, but hopefully someone here can suggest a good marker.
Good luck!