Vibratome 1000

Viral expression was confirmed post-mortem via immunohistochemistry (Figure 2G, Figure S4A) consistent with previous results in our laboratory (Aizenberg et al., 2015 (link); Natan et al., 2015 ). Brains were post-fixed in paraformaldehyde (4%, PFA) and cryoprotected in 30% sucrose. Coronal sections (50μm) for PV were cut using a cryostat (Leica CM1860) and SOM were cut using a vibratome (Vibratome 1000). Sections were washed in PBS containing 0.1% Triton X-100 (PBST; 3 washes, 5 min), incubated at room temperature in blocking solution (for PV 10% normal goat serum and 5% bovine serum albumin in PBST for 3hr; for SOM 1% normal horse serum with 0.1% bovine serum albumin and 0.5% Triton X-100 in PBS for 1hr), and then incubated in primary antibody diluted in blocking solution overnight at 4°C. The following primary antibodies were used: anti-PV (PV 25 rabbit polyclonal, 1:500, Swant) or anti-SOM (MAB354 rat monoclonal, 1:200, Millipore, clone YC7). After incubation, sections were washed in blocking solution (3 washes, 5 min), incubated for 2hr at room temperature with secondary antibodies (Alexa 594 goat anti-rabbit IgG 1:1000 for PV and Alexa 568 goat anti-rat IgG 1:750 for SOM), and then washed in PBS (3 washes, 5min each). Sections were mounted using fluoromount-G (Southern Biotech) and confocal images were acquired (Leica SP5).