Project description:Mice lacking the developmental axon guidance molecule EphA4 have previously been shown to exhibit extensive axonal regeneration and functional recovery following spinal cord injury. To assess mechanisms by which EphA4 may modify the response to neural injury, a microarray was performed on spinal cord tissue from mice with spinal cord injury and sham injured controls. RNA was purified from spinal cords of adult EphA4 knockout and wild-type mice four days following lumbar spinal cord hemisection or laminectomy only and was hybridised to Affymetrix All-Exon Array 1.0 GeneChips. While subsequent analyses indicated that several pathways were altered in EphA4 knockout mice, of particular interest was the attenuated or otherwise altered expression of a number of inflammatory genes, including Arginase 1, expression of which was lower in injured EphA4 knockout compared to wild-type mice. Immunohistological analyses of different cellular components of the immune response were then performed in injured EphA4 knockout and wild-type spinal cords. While numbers of infiltrating CD3+ T cells were low in the hemisection model, a robust CD11b+ macrophage / microglial response was observed post-injury. There was no difference in the overall number or spread of macrophages / activated microglia in injured EphA4 knockout compared to wild-type spinal cords at two, four or fourteen days post-injury, however a lower proportion of Arginase-1 immunoreactive macrophages / activated microglia was observed in EphA4 knockout spinal cords at four days post-injury. Subtle alterations in the neuroinflammatory response in injured EphA4 knockout spinal cords may contribute to the regeneration and recovery observed in these mice following injury. Comparison was made between gene expression in wild-type and knockout samples both before and after injury. 3 replicates per group.
Project description:Mice lacking the developmental axon guidance molecule EphA4 have previously been shown to exhibit extensive axonal regeneration and functional recovery following spinal cord injury. To assess mechanisms by which EphA4 may modify the response to neural injury, a microarray was performed on spinal cord tissue from mice with spinal cord injury and sham injured controls. RNA was purified from spinal cords of adult EphA4 knockout and wild-type mice four days following lumbar spinal cord hemisection or laminectomy only and was hybridised to Affymetrix All-Exon Array 1.0 GeneChips. While subsequent analyses indicated that several pathways were altered in EphA4 knockout mice, of particular interest was the attenuated or otherwise altered expression of a number of inflammatory genes, including Arginase 1, expression of which was lower in injured EphA4 knockout compared to wild-type mice. Immunohistological analyses of different cellular components of the immune response were then performed in injured EphA4 knockout and wild-type spinal cords. While numbers of infiltrating CD3+ T cells were low in the hemisection model, a robust CD11b+ macrophage / microglial response was observed post-injury. There was no difference in the overall number or spread of macrophages / activated microglia in injured EphA4 knockout compared to wild-type spinal cords at two, four or fourteen days post-injury, however a lower proportion of Arginase-1 immunoreactive macrophages / activated microglia was observed in EphA4 knockout spinal cords at four days post-injury. Subtle alterations in the neuroinflammatory response in injured EphA4 knockout spinal cords may contribute to the regeneration and recovery observed in these mice following injury.
Project description:We profiled spinal cord tissue at the site of a moderate contusion injury at the level of the thoracic spinal cord We examined several timepoints following injury, including sham and days 1,3 and 7 following injury and compared differential expression of genes within a genotype and across genotypes (trkB.T1KO/trkB.T1WT) at each timepoint.
Project description:We profiled spinal cord tissue at the site of a moderate contusion injury at the level of the thoracic spinal cord We examined several timepoints following injury, including sham and days 1,3 and 7 following injury and compared differential expression of genes within a genotype and across genotypes (trkB.T1KO/trkB.T1WT) at each timepoint. Tissue was profiled at baseline (sham) condition and then 1, 3 and 7 days after thoracic moderate contusion injury
Project description:Single-nuclei Assay for Transposase-Accessible Chromatin with sequencing (snATACseq) was applied to examine chromatin landscape changes and transcriptional regulator (TR) DNA motif accessibility in reactive astrocytes following traumatic spinal cord injury (SCI). Astrocyte nuclei were isolated from the spinal cord of wild type mice and mice with astrocyte-specific conditional gene deletion (cKO) of test-case TRs, SMARCA4 (Smarca4-astro-cKO) or STAT3 knockout (Stat3-astro-cKO). Comparison of differential chromatin accessibility revealed substantial remodeling during astrocyte reactivity, with more chromatin opening than closing. Marked alterations in access to SCI reactivity-associated TR motifs were also detected.
Project description:Summary: Spinal cord injury (SCI) is a damage to the spinal cord induced by trauma or disease resulting in a loss of mobility or feeling. SCI is characterized by a primary mechanical injury followed by a secondary injury in which several molecular events are altered in the spinal cord often resulting in loss of neuronal function. Analysis of the areas directly (spinal cord) and indirectly (raphe and sensorimotor cortex) affected by injury will help understanding mechanisms of SCI. Hypothesis: Areas of the brain primarily affected by spinal cord injury are the Raphe and the Sensorimotor cortex thus gene expression profiling these two areas might contribute understanding the mechanisms of spinal cord injury. Specific Aim: The project aims at finding significantly altered genes in the Raphe and Sensorimotor cortex following an induced moderate spinal cord injury in T9.