VIP and infection: One week after the injection of AAV2/1-SynTetOff-FLEX-FGL-2A-palmRFP1 into the superficial layer in the S1BF of VIP-Cre knock-in mice, we observed the immunoreactivities for GFP and mRFP1 under a confocal laser scanning microscope, and selected three samples in which the infection was restricted to L2/3 VIP+ neurons (Fig 5A–5E).