Figure 10

Anti-α6 or β1 integrin antibody blocks laminin-induced neural progenitor expansion. Antibody perturbation experiments were carried out in dark EB-derived neural populations at 24 h postplating on laminin substrate at 60 μg/ml. A 10 μg/ml of antibody against α6 or β1 integrin, and a 10 μg/ml of purified mouse IgG were added into the culture medium directly at the beginning of cell culture. The expansion distance was determined by measuring the length from the edge of EB spheres to the widest point of the rim. (A-D) Immunofluorescent images of dark EB-derived neural populations show representative fields of nestin+ cells treated with anti-α6 (B), anti-β1 (C), mouse IgG (D), and untreated (A). Inclusion of antibody against α6 or β1 significantly decreases cell expansion compared to untreated culture (A) and culture treated with mouse IgG (D). The bar in (A) = 503 μm, in (B) = 231 μm, in (C) = 266 μm, and in (D) = 466 μm. (E) Bar plot summarizes the effects of various treatments on laminin-induced expansion distances. Values are expressed in expansion distance as mean ± SEM of four independent experiments. Statistical differences for expansion distance between anti-α6 or β1 integrin treatment and untreated or treated with mouse IgG are significant: **p < 0.001. But the differences for expansion distance between mouse IgG treatment and untreated are not significant p > 0.05. Scale bar in (A) = 100 μm.