Extended Data Fig. 4: Long-term biointegration of the micro-LED array.
From: Wireless closed-loop optogenetics across the entire dorsoventral spinal cord in mice
Step 1: Stepwise surgical insertion of the micro-LED array into the epidural space. Micro-LED array overlaying a spinal cord surrogate, bottom right inset. Step 2: Post-mortem evaluation of foreign body responses within the dorsal horn of spinal segments located below the micro-LED array. Coronal spinal cord sections of mice implanted for 1, 4 or 6 weeks were stained against Iba1 and GFAP proteins, and compared with the spinal cord of non-implanted mice. Histogram plots report the fluorescent staining intensity quantified within the dorsal horns. The photograph shows the staining from a window within the dorsal horn, as shown in the scheme (n = 6 healthy mice, n=4 for each timepoint post-implantation one-way ANOVA, Iba1 p = 0.64, GFAP p = 0.36, mean±s.e.m.). Step 3: Schematic illustrating the post-mortem evaluation of spinal cord circularity. The bar graph reports the mean circularity (n=6 mice, one-way ANOVA, p = 0.95, mean±s.e.m.). Step 4: Photographs show examples of subcutaneous wires taken in mice that were implanted for 4 weeks.
