Fig. 2

Immunohistochemical distribution of NLGN4 in the human cerebral cortex. A A representative image of the adult human cerebral cortex (case ID: A3). The positions of cortical layers III, V, and VI are indicated. B A magnified view of the boxed area in A. C A representative image of the adult human cerebral cortex (case ID: A6) examined with ant-NL4-m1. The positions of cortical layers III, V, and VI are indicated. D A magnified view of the boxed area in C. E A high-magnification view of layer V in the adult female cerebral cortex (case ID: A5). Remarkable NLGN4 expression was observed as in the male cerebral cortex. F A representative image of the neonatal cerebral cortex (case ID: N8). The cortical layer structure is unclear, and NLGN4-positive neurons appear evenly distributed. G A magnified view of the boxed area in F. Most neurons expressed NLGN4. H Another representative image of the neonatal cerebral cortex (case ID: N10). An incomplete layer structure was present in this case. I A magnified view of the solid-boxed area in H. Granular cells in layer II and pyramidal cells in layer III expressed NLGN4 at various levels. J A magnified view of the dashed-boxed area in H. Large pyramidal cells in layers V and VI expressed NLGN4 at various levels. Intense NLGN4 signals were noted in a pyramidal cell (black arrowhead) as in the adult cerebral cortex. Scale bars = 200 μm (A, F, H), 50 μm (B–E, G, I, J)