Figure 1.

(a) General pipeline of the establishment of an optogenetically modular neuromuscular junction (NMJ) compartmentalized microfluidic platform (see Material and Methods for details). (b) Low magnification photomicrograph of the assembled microfluidic device. (c) SMI31-positive neurons in a spinal cord explant cultured for 15 days in the neuronal chamber during the second phase of the protocol (violet arrow in (a)). (d) Myosin heavy chain (MHC)-positive myotubes cultured for 15 days in the first phase of the protocol (blue arrow in (a)). Scale bars: (b) = 2.5 cm; (c) = 50 µm, and (d) = 75 µm.