Figure 1.

Astrocyte toxicity to motor neurons is reduced when astrocytes are pre-treated with MSC-derived EVs. (a–d) Viability of motor neurons (MNs) co-cultured with WT astrocytes, untreated (b) and EV-treated (c) spinal cord astrocytes from adult SOD1^G93A mice. (a,c) Representative phase-contrast microscopy images (100×) of MNs at day 8 of co-culture with WT astrocytes (a), untreated SOD1^G93A astrocytes (b) or with SOD1^G93A astrocytes pre-treated for 24 h with EVs (c); scale bar: 50 µm. (d) Quantification of MN viability expressed as percent (%) MN survival (calculated with respect to the total number of MN at day 4 in vitro -4DIV) when co-cultured with WT astrocytes, untreated or EV-treated SOD1^G93A astrocytes. Data represent the means ± SEM of n = 5–6 independent experiments. Statistical significance for p < 0.05 at least (* vs. WT and # vs. MNs + untreated SOD1^G93A astrocytes; one-way ANOVA, followed by Bonferroni post hoc test). (e–g) Viability of MNs co-cultured with untreated and EV-treated patient-derived reprogrammed astrocytes (iAstrocytes). (e,f) Representative InCell images of MNs after 3 days of co-culture with iAstrocytes, untreated (e) or treated (f) with human-MSC-derived EVs. (g) Quantification of MN survival expressed as the percentage of MNs with axon (calculated with respect to the total number of MNs at day 1) after 3 days of co-culture with iAstrocytes untreated or pre-treated with EVs. Data represent the means ± SEM of n = 3 independent experiments. Statistical significance (*) vs. untreated conditions for p < 0.05 at least (two-tailed Student’s t-test). t = −2.167, p = 0.046 vs. 78(C9) untreated iAstrocytes; t = −3.393, p = 0.009 vs. 183(C9) untreated iAstrocytes.