biostudies-literaturePan DU.S. Department of Health & Human Services | NIH | National Institute on Aging (U.S. National Institute on Aging)27https://www.ebi.ac.uk/biostudies/studies/S-EPMC12936232biostudies-literatureUnknown14(1)Spinal cord injury (SCI) often causes long-term disability. But effective means to promote proper regeneration after SCI has so far failed to reach the clinic. Here, we report that fibrotic scar formation at injury sites prevents recovery after SCI and that the inhibition of fibrotic scar formation significantly improved SCI recovery in adult mice. We found that after SCI there is an elevation of macrophages, which are a primary source of activated transforming growth factor-β 1 (TGF-β1) that in turn recruits mesenchymal stromal/stem cells (MSCs) to induce their fibroblast differentiation, thus promoting scar formation. We also found that activated TGF-β1 acts on resident pericytes in the endothelial niche of the blood-spinal cord barrier to promote their differentiation into fibroblasts, Bone researchTGF-β-induced fibrotic scar formation limits recovery of spinal cord injury.PMC12936232R01AG076783P01AG066603R01AG068997Pan DCao XNoller KWu PCahan PfalseTGF-β-induced fibrotic scar formation limits recovery of spinal cord injury.Spinal cord injury (SCI) often causes long-term disability. But effective means to promote proper regeneration after SCI has so far failed to reach the clinic. Here, we report that fibrotic scar formation at injury sites prevents recovery after SCI and that the inhibition of fibrotic scar formation significantly improved SCI recovery in adult mice. We found that after SCI there is an elevation of macrophages, which are a primary source of activated transforming growth factor-β 1 (TGF-β1) that in turn recruits mesenchymal stromal/stem cells (MSCs) to induce their fibroblast differentiation, thus promoting scar formation. We also found that activated TGF-β1 acts on resident pericytes in the endothelial niche of the blood-spinal cord barrier to promote their differentiation into fibroblasts, 2026-01-01T00:00:00Z2026 Feb2026-07-16T22:09:10.024Z2026-07-11T03:11:47.052ZS-EPMC129362324174140610.1038/s41413-026-00507-7