Figure 5.

The functionality of neuronal circuitry is compromised in human adult cortical organotypic tissue after 4 weeks in culture

(A and B) Representative confocal images of (A) acute and (B) 4-week-cultured human cortical tissue showing the expression of the neuronal markers NeuN and MAP2. Arrows indicate colocalization. Nuclear staining (Hoechst, blue) is included in the merged panel.

(C–J) Examples of cortical neurons recorded in 4-week-cultured human cortical tissue. (C and G) Biocytin labeling of the recorded neurons. (D–F) Whole-cell patch-clamp recording traces from the cell in (C). The cell is not able to fire AP either at step (250 pA) (D) or at the ramp (0–300 pA) (E) current injection in current clamp mode. (F) The same cell has a very small inward sodium current upon 10 mV depolarization step in voltage-clamp mode at −70 mV holding potential. (H–J) Patch-clamp recording of another cell, shown in (G), that was able to generate a single AP in the similar protocol as above (H and I), with a bigger sodium current in voltage-clamp mode (J). Scale bars are the same for the upper and lower panels of the traces unless otherwise indicated. Ho, Hoechst. Scale bars, 50 μm.