Extended Data Figure 8. Migration of Dlx2i1/2b::eGFP cells in mouse and human forebrain brain slices versus hSS-hCS.

(a, b, c) Representative images of human fetal cortex at GW20 showing immunostaining with antibodies against GFAP, BCL11B (CTIP2) and GABA. (d) Representative image showing cell labeling with the Dlx2i1/2b::eGFP reporter in human forebrain at GW18 (6 days after lentivirus infection) (e, f) Representative immunostainings in cryosections of human tissue at GW18 showing co-localization of Dlx2i1/2b::eGFP with NKX2-1 and GABA. (g) Representative images showing cell labeling with the Dlx2i1/2b::eGFP reporter in hSS-hCS (9 days after assembly), in human forebrain (GW18) and in mouse slice cultures (E18). (h, i) Comparison of Dlx2i1/2b::eGFP⁺ cell size and quantification of the ratio of soma diameter to the length of the leading process in fused hSS-hCS (n= 25 cells from 4 hiPSC lines), human forebrain at GW18 (n= 19 cells; black) and GW20 (n= 15 cells; gray), hSS-derived cells cultured on E14 mouse forebrain slices (n= 14 cells), and E18 mouse forebrain slices (n= 30 cells from 2 litters) (one-way ANOVA, interaction F(3, 97)= 11.61, P= 0.001, Bonferroni post-hoc ***P< 0.001, **P< 0.05). (j, k, l) Comparison of the number of saltations (n= 56 cells from 2 hiPSC lines; one-way ANOVA, interaction F(2, 103)= 29.27, P= 0.001, Bonferroni post-hoc ***P< 0.001), saltation length (n= 44 cells from 3 hiPSC lines; one-way ANOVA, interaction F(2, 91)= 3.0, P= 0.50), speed when mobile (n= 38 cells from 3 hiPSC lines; one-way ANOVA, interaction F(2, 83)= 11.38, P= 0.001, Bonferroni post-hoc ***P< 0.001) for Dlx2i1/2b::eGFP⁺ in fused hSS-hCS, human fetal forebrain (GW18: n= 19 cells; GW20: n= 15 cells), and E18 mouse forebrain slices (n= 14 cells for saltation length and speed, n= 16 cells for number of saltations from 2 litters). Data are mean ± s.e.m.