Fig. 5: Sulfatase promotes inhibitory WNT and BMP signaling on oligodendrocyte differentiation following demyelination.

Pharmacological manipulation of WNT and BMP signaling was performed in the context of Sulf1/2 cKO. WNT pathway activator (CHIR-99021, 3 µM), WNT antagonist (XAV939, 100 nM), BMP pathway activator (A01, 100 nM), or receptor antagonist (LDN-193189, 100 nM) were co-injected with lysolecithin. a–j Oligodendrocyte lineage cell density was assessed by Olig2 (green) and CC1 (red) widefield immunofluorescence. Density of Olig2⁺ oligodendrocyte lineage cells (k), Olig2⁺CC1⁺ postmitotic oligodendrocyte (l), and percentage of CC1⁺ oligodendrocytes (m) quantified (k–m, n = 8, 5, 4, 6, 8, 5, 4, 7, 5, and 3 mice from left to right, for ctrl, CHIR, XAV, A01, and LDN treatment groups, in WT and Sulf1/2 cKO mice respectively). Two-way ANOVA was performed (see Source data for full details). Holm–Sidak multiple comparisons tests vs. ctrl wild-type (blue *) or ctrl Sulf1/2 cKO (red *), or as indicated. *, **, ***, and **** indicated p < 0.05, <0.01, <0.001, and <0.0001 respectively. n hOPCs were co-infected with lentiviral SULF2 shRNAi or scrambled control and lentiviral TCF/LEF reporter virus and exposed to WNT3A (50 ng/mL) or vehicle control. Two-way RM ANOVA followed by Holm–Sidak post-test (n = 4 fetal human samples, mean ± SEM normalized to control). o hOPCs infected with lentiviral BMP reporter and SULF2 KD virus. SULF2 KD reduced BMP activity in hOPCs following BMP7 treatment (50 ng/mL) (n = 5, p < 0.05 two-way RM ANOVA Holm–Sidak post-test). Two-way ANOVA revealed significant main effects for ligand treatment, SULF2 KD, and the interaction for both WNT and BMP. p quantification of O4⁺ oligodendrocyte differentiation following SULF2 KD and BMP7 treatment (5–50 ng/mL BMP7) (n = 5 at 5 ng/mL BMP7 and n = 6 at 0 and 50 ng/mL BMP7 individual fetal human samples). SULF2 knockdown attenuated the effects of WNT/BMP signaling and significantly increased differentiation of hOPCs in the presence of BMP (mixed-effects model; Sidak’s post-test, p < 0.05). * and ** indicate p < 0.05 and < 0.01, respectively. Mean ± SEM is shown. Scale: 20 μm (a–j). n.s. Not significant.