Fig. 7

Patterning neuronal networks via patterned astrocytes a Purified cerebral astrocytes patterned on SAMs. GFAP (green channel) is the astrocyte marker. This photomicrograph was taken 2 h after plating astrocytes. b Patterning neurons over patterned astrocytes. Neuronal marker Tuj1 and astrocyte marker GFAP are used to distinguish the two cell populations that are homogeneously distributed over the pattern. This laser scanning confocal photomicrograph was taken 1 DIV after plating neurons. c Three-dimensional reconstruction of the neuronal networks, the neuronal networks have developed extensively to envelop the astrocytes. Note that this picture is shown upside down. This laser scanning confocal photomicrograph was taken 6 DIV after plating neurons. d Scatterograph of the number of neurons per unit area with respect to the number of astrocytes underneath (if applicable). Red dots show the group in which neurons are seeded over astrocytes- patterned surfaces. This is further classified into two groups with astrocytes seeded at intentionally different densities. Brown dots show the group of 50 µg/mL PDL treated surface, and blue dots show the group of MG- treated surface. The data on PDL and MG for generating the figure here is the same set of data for Fig. 1. e Significance differences exist between astrocyte patterned surfaces and MG- and PDL- treated surfaces. Neuronal adherence is also significantly different on surfaces with different astrocyte density. Ah denotes high-density astrocyte pattern, Al denotes low-density astrocyte pattern. (***P < 0.001, Kruskal–Wallis’s ANOVA with Tukey–Kramer’s post hoc test. n = 8 in high-density astrocyte pattern, n = 10 in low-density astrocyte pattern, n = 9 in PDL, n = 6 in MG.) Scale bars 50 µm