The immunohistochemistry (IHC) was performed as previously described by us (10 (link),38 ). Briefly, fixed brains were dehydrated, embedded in paraffin and sectioned into 5µm thick sections using microtome (Leica Microsystems Inc., Buffalo Grove, IL). The sections were deparaffinized and rehydrated using xylene, ethanol and double-distilled water washes. Antigens were unmasked by boiling the sections in 10 mM sodium citrate buffer (pH 6.0) and the sections were washed and incubated in 3% hydrogen peroxide solution. The sections were blocked with 5% goat serum and incubated with primary antibodies for integrinβ4 (1:100) and cleaved caspase 3 (1:100) overnight at 4°C. Next day the slides were stained using Ultravision ONE HRP polymer kit (Thermofisher scientific, Fremont, CA) as per the manufacturer’s instructions. The sections were counterstained with Mayer’s hematoxylin and dehydrated. The slides were mounted using Permount (Fisher scientific, Fair Lawn, NJ) and imaged using Olympus microscope (Olympus America Inc, Center Valley, PA).