Small RNAs including microRNAs (miRNAs) and tRNA fragments (tRFs) are key post-transcriptional regulators of gene expression in temporal lobe epilepsy (TLE), but the cellular origin of these changes is often unclear. Here, we dissected the cell-type specific small RNA landscape, focussing on miRNA and tRFs, during epileptogenesis and in chronic epilepsy by profiling the RNA-induced silencing complex (RISC) using novel, transgenic mice with inducible expression of a FLAG-tagged Argonaute 2 protein driven specifically in neurons (Thy1-Ago2) or microglia (Cx3cr1-Ago2). We induced epilepsy in male mice via intra-amygdala microinjection of kainic acid and tracked miRNA expression over time in the hippocampus. Microglia and neurons displayed distinct and largely non-overlapping small RNA profiles across disease. Shortly following the epileptogenic insult, we detected a rapid microglial miRNA and tRF response which was sustained in chronic stages of the disease whereas small RNA changes in neurons displayed a delayed but sustained wave of unique changes as the disease progressed. Interestingly, our data reveals selective loading and incorporation of miRNAs into Ago2/RISC complexes, independent of overall abundance, in a cell- and disease-stage specific manner as well as differential processing of tRNAs in microglia compared to neurons. Additionally we found that certain epilepsy-associated miRNAs, previously considered ubiquitous, display dysregulation in multiple cell types while exhibiting cell-specific activity. Together our results demonstrate the cell-specific small RNA responses and functions to epileptogenic insults and shed further light on the complexity of post-transcriptional gene dysregulation in TLE. The findings indicate the potential advantages of targeted, cell-specific therapeutic strategies to effectively modulate miRNA pathways in epilepsy.

Neuroinflammation is a multicellular immune response within the central nervous system (CNS) triggered by injury, infection, or disease, and it drives long-term changes in neurons and glia. Understanding this mechanism is important for advancing research into neurodegenerative diseases and trauma-induced CNS damage. Three-dimensional (3D) cell culture models offer enhanced structural and functional capabilities compared to traditional 2D models, yet their implementation remains challenging. Key limitations include cell survival, faithful recapitulation of CNS cellular diversity, simulation of immune responses, and issues of scalability and long-term culture. This review explores state-of-the-art methods for incorporating neurons, astrocytes, microglia, oligodendrocytes, and other CNS-relevant cell types into 3D models to study neuroinflammation. Additionally, it examines emerging trends in bioengineering, co-culture strategies, and dynamic systems that improve model scalability and longevity. By critically evaluating both established and innovative protocols, we aim to provide guidance for researchers in selecting effective methodologies and to accelerate the development of physiologically relevant in vitro models for neuroinflammation research.

Spinal cord injury (SCI) is a severe neurological condition with limited regenerative capacity and no effective curative treatments. Interleukin-13 (IL-13), an immunomodulatory cytokine, has shown therapeutic potential by promoting alternative immune activation and improving recovery after SCI in mice. However, cell-based IL-13 delivery is hindered by poor graft survival and limited localisation at the injury site. Here, we developed an injectable hydrogel-based delivery system (HGIL13) composed of IL-13-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles embedded in a photocrosslinkable gelatin methacrylate (GelMA) matrix, enabling sustained and localised IL-13 release. HGIL13 achieved IL-13 release for up to six weeks and significantly reduced lipopolysaccharide (LPS)-induced inflammation in BV2 microglia in vitro. In a mouse contusion SCI model, HGIL13 enhanced functional recovery, reduced lesion volume, and decreased demyelinated area. Using the HexbtdTomato mouse we show that HGIL13 modulated the neuroimmune response by decreasing resident microglia density, downregulating CD86 expression, and upregulating Arginase-1 in both microglia and infiltrating monocyte-derived macrophages. RT-qPCR and RNA-seq analyses confirmed sustained immunomodulation over 28 days and indicated early reduction of activated microglia at 7 days post-injury as a key therapeutic mechanism. This study presents a safe, effective, and translatable strategy for localised cytokine delivery, demonstrating strong potential for immunomodulation and improved functional recovery following SCI.

Traumatic spinal cord injury (SCI) is a severe clinical challenge, often leading to long-term sensory, motor, and autonomic dysfunction. The SCI cascade involves a primary physical damage phase, followed by a secondary phase of inflammatory signalling driven by microglia and other infiltrating immune cells. Immunomodulatory therapies may help promote healing and restrict secondary damage. We have previously demonstrated that interleukin (IL)-13 delivery improves functional and histopathological recovery after SCI in murine models, primarily by polarising macrophages towards an alternatively activated pro-reparative M2-like phenotype and reducing axonal contacts. Although microglia respond robustly to IL-13 in vitro, polarisation of microglia in vivo is more difficult. To better understand what conditions may restrict microglial responses to IL-13 in vivo, we sought to examine the effect of cellular context or microenvironment on IL-13 efficacy in forcing microglia polarisation in vitro. BV2 and murine induced pluripotent stem cell (miPSC)-derived microglia were treated with IL-13 alone or in combination with lipopolysaccharide (LPS), acidic media, extracellular matrix components, high glutamate or high potassium concentrations. Following this phenotypic changes including morphology, gene/protein expression (TNFα, IL-1β, iNOS, Arg-1, CD206, F4-80) and cytokine release (TNFα) were measured using high-content screening, RT-qPCR, immunohistochemistry, and ELISA. IL-13 leads to increased expression of the anti-inflammatory marker Arg-1 while lowering expression and secretion of the pro-inflammatory markers IL-1β, iNOS, and TNFα, and expression of the microglia activation marker F4-80, signifying effective polarisation of microglia. Concomitant administration of LPS with IL-13 reduces IL-13 polarisation efficacy in microglia. Forced polarisation of microglia is also compromised by high glutamate tone, acidosis, hyperkalemia, and extracellular fibronectin, suggesting microenvironmental contexts seen in neurotrauma directly act on microglia to limit polarisation potential. Our study demonstrates that the post-SCI environment dampens IL-13 efficacy on microglia. Taken together these data caution against simple immunomodulatory strategies and suggest that effective polarisation of microglia in vivo will require multimodal approaches.

Spinal cord injury (SCI) is a devastating condition for which no curative therapy is currently available. The pathology of SCI is underscored by an inflammatory lesion at the site of injury that exacerbates damage and impedes recovery. Immunomodulation is a promising strategy for SCI repair and thus there is enhanced focus on identifying and testing novel immunotherapeutics. Efficient preclinical models are required for screening new therapies, and ex vivo models can reduce the overall cost and animal numbers required for this process. Organotypic spinal cord slices offer a promising ex vivo platform for modelling spinal cord pathologies as they retain the in vivo tissue architecture with the benefit of a controlled culture environment. Neuroinflammation can be induced in organotypic spinal cord slices by adding inflammatory agents to the culture system, however this results in global inflammation and lacks the heterogeneity of a focal lesion surrounded by spared tissue that is observed in vivo. To improve this model, we have applied previously characterised macroporous cryogels for localised delivery of lipopolysaccharide (LPS) in organotypic spinal cord slices. Placement of LPS-loaded cryogels adjacent to spinal cord slices increases the expression of proinflammatory CD86 in Iba-1+ microglia/macrophages and decreases the expression of myelin basic protein at the lesion site. These effects are not observed distal to the cryogel, indicating the formation of a focal inflammatory lesion. These effects can be reversed through treatment with the immunomodulatory cytokine interleukin(IL)-13. This novel model of neuroinflammation provides an innovative platform for screening potential immunotherapeutics and improving the efficiency of future preclinical SCI studies.

Spinal cord injury (SCI) is a devastating condition with no curative therapy currently available. Immunomodulation can be applied as a therapeutic strategy to drive alternative immune cell activation and promote a proregenerative injury microenvironment. Locally injected hydrogels carrying immunotherapeutic cargo directly to injured tissue offer an encouraging treatment approach from an immunopharmacological perspective. Gelatin methacrylate (GelMA) hydrogels are promising in this regard, however, detailed analysis on the immunogenicity of GelMA in the specific context of the SCI microenvironment is lacking. Here, the immunogenicity of GelMA hydrogels formulated with a translationally relevant photoinitiator is analyzed in vitro and ex vivo. 3% (w/v) GelMA, synthesized from gelatin type-A, is first identified as the optimal hydrogel formulation based on mechanical properties and cytocompatibility. Additionally, 3% GelMA-A does not alter the expression profile of key polarization markers in BV2 microglia or RAW264.7 macrophages after 48 h. Finally, it is shown for the first time that 3% GelMA-A can support the ex vivo culture of primary murine organotypic spinal cord slices for 14 days with no direct effect on glial fibrillary acidic protein (GFAP+ ) astrocyte or ionized calcium-binding adaptor molecule 1 (Iba-1+ ) microglia reactivity. This provides evidence that GelMA hydrogels can act as an immunotherapeutic hydrogel-based platform for preclinical SCI.

Live-cell imaging is a common technique in microscopy to investigate dynamic cellular behaviour and permits the accurate and relevant analysis of a wide range of cellular and tissue parameters, such as motility, cell division, wound healing responses and calcium (Ca2+) signalling in cell lines, primary cell cultures and ex vivo preparations. Furthermore, this can occur under many experimental conditions, making live-cell imaging indispensable for biological research. Systems which maintain cells at physiological conditions outside of a CO2 incubator are often bulky, expensive and use proprietary components. Here we present an inexpensive, open-source temperature control system for in vitro live-cell imaging. Our system ‘ThermoCyte’, which is constructed from standard electronic components, enables precise tuning, control and logging of a temperature ‘set point’ for imaging cells at physiological temperature. We achieved stable thermal dynamics, with reliable temperature cycling and a standard deviation of 0.42°C over 1 h. Furthermore, the device is modular in nature and is adaptable to the researcher's specific needs. This represents simple, inexpensive and reliable tool for laboratories to carry out custom live-cell imaging protocols, on a standard laboratory bench, at physiological temperature.

Traumatic spinal cord injury (SCI) most often leads to permanent paralysis due to the inability of axons to regenerate in the adult mammalian central nervous system (CNS). In the past, we have shown that mast cells (MCs) improve the functional outcome after SCI by suppressing scar tissue formation at the lesion site via mouse mast cell protease 6 (mMCP6). In this study, we investigated whether recombinant mMCP6 can be used therapeutically to improve the functional outcome after SCI. Therefore, we applied mMCP6 locally via an intrathecal catheter in the subacute phase after a spinal cord hemisection injury in mice. Our findings showed that hind limb motor function was significantly improved in mice that received recombinant mMCP6 compared with the vehicle-treated group. In contrast to our previous findings in mMCP6 knockout mice, the lesion size and expression levels of the scar components fibronectin, laminin, and axon-growth-inhibitory chondroitin sulfate proteoglycans were not affected by the treatment with recombinant mMCP6. Surprisingly, no difference in infiltration of CD4+ T cells and reactivity of Iba-1+ microglia/macrophages at the lesion site was observed between the mMCP6-treated mice and control mice. Additionally, local protein levels of the pro- and anti-inflammatory mediators IL-1 beta, IL-2, IL-4, IL-6, IL-10, TNF-alpha, IFN gamma, and MCP-1 were comparable between the two treatment groups, indicating that locally applied mMCP6 did not affect inflammatory processes after injury. However, the increase in locomotor performance in mMCP6-treated mice was accompanied by reduced demyelination and astrogliosis in the perilesional area after SCI. Consistently, we found that TNF-alpha/IL-1 beta-astrocyte activation was decreased and that oligodendrocyte precursor cell (OPC) differentiation was increased after recombinant mMCP6 treatment in vitro. Mechanistically, this suggests effects of mMCP6 on reducing astrogliosis and improving (re)myelination in the spinal cord after injury. In conclusion, these data show for the first time that recombinant mMCP6 is therapeutically active in enhancing recovery after SCI.

Traumatic spinal cord injuries result from high impact forces acting on the spine and are proceeded by an extensive secondary inflammatory response resulting in motor, sensory, and autonomic dysfunction. Experimental in vivo traumatic spinal cord injuries in rodents using a contusion model have been extremely useful in elucidating the underlying pathophysiology of these injuries. However, the relationship between the pathophysiology and the biomechanical factors is still not well understood. Therefore, the aim of this research is to provide a comprehensive analysis of the biomechanics of traumatic spinal cord injury in a rat contusion model. This is achieved through the development and validation of a finite element model of the thoracic rat spinal cord and subsequently simulating controlled cortical impact-induced traumatic spinal cord injury. The effects of impactor velocity, depth, and geometry on the resulting stresses and strains within the spinal cord are investigated. Our results show that increasing impactor depth results in larger stresses and strains within the spinal cord tissue as expected. Further, for the first time ever our results show that impactor geometry (spherical versus cylindrical) plays an important role in the distribution and magnitude of stresses and strains within the cord. Therefore, finite element modelling can be a powerful tool used to predict stresses and strains that occur in spinal cord tissue during trauma.

Traumatic spinal cord injury (SCI) is a devastating condition that significantly impacts motor, sensory and autonomic function in patients. Despite advances in therapeutic approaches, there is still no curative therapy currently available. Neuroinflammation is a persisting event of the secondary injury phase of SCI that affects functional recovery, and modulation of the inflammatory response towards a beneficial anti-inflammatory state can improve recovery in preclinical SCI models. In human SCI patients, rehabilitative exercise, or motor rehabilitation as we will refer to it from here on out, remains the cornerstone of treatment to increase functional capacity and prevent secondary health implications. Motor rehabilitation is known to have anti-inflammatory effects; however, current literature is lacking in the description of the effect of motor rehabilitation on inflammation in the context of SCI. Understanding the effect on different inflammatory markers after SCI should enable the optimization of motor rehabilitation as a therapeutic regime. This review extensively describes the effect of motor rehabilitation on selected inflammatory mediators in both preclinical and human SCI studies. Additionally, we summarize how the type, duration, and intensity of motor rehabilitation can affect the inflammatory response after SCI. In doing so, we introduce a new perspective on how motor rehabilitation can be optimized as an immunomodulatory therapy to improve patient outcome after SCI.

Spinal cord injury (SCI) is a complex medical and psychological challenge for which there is no curative therapy currently available. Despite major progress in pharmacological and surgical approaches, clinical trials for SCI patients have been uniformly disappointing thus far as there are many practical and biological issues yet to be resolved. Neuroinflammation is a critical event of the secondary injury phase after SCI, and recent research strategies have focused on modulating the immune response after injury to provide a more favorable recovery environment. Biomaterials can serve this purpose by providing physical and trophic support to the injured spinal cord after SCI. Of all potential biomaterials, functional hydrogels are emerging as a key component in novel treatment strategies for SCI, including controlled and localized delivery of immunomodulatory therapies to drive polarization of immune cells towards a pro-regenerative phenotype. Here, we extensively review recent developments in the use of functional hydrogels as immunomodulatory therapies for SCI. We briefly describe physicochemical properties of hydrogels and demonstrate how advanced fabrication methods lead to the required heterogeneity and hierarchical arrangements that increasingly mimic complex spinal cord tissue. We then summarize potential SCI therapeutic modalities including: (i) hydrogels alone; (ii) hydrogels as cellular or (iii) bioactive molecule delivery vehicles, and; (iv) combinatorial approaches. By linking the structural properties of hydrogels to their functions in treatment with particular focus on immunopharmacological stimuli, this may accelerate further development of functional hydrogels for SCI, and indeed next-generation central nervous system regenerative therapies.

Spinal cord injury (SCI) elicits a robust neuroinflammatory reaction which, in turn, exacerbates the initial mechanical damage. Pivotal players orchestrating this response are macrophages (Mφs) and microglia. After SCI, the inflammatory environment is dominated by pro-inflammatory Mφs/microglia, which contribute to secondary cell death and prevent regeneration. Therefore, reprogramming Mφ/microglia towards a more anti-inflammatory and potentially neuroprotective phenotype has gained substantial therapeutic interest in recent years. Interleukin-13 (IL-13) is a potent inducer of such an anti-inflammatory phenotype. In this study, we used genetically modified Mφs as carriers to continuously secrete IL-13 (IL-13 Mφs) at the lesion site. Mφs were genetically modified to secrete IL-13 (IL-13 Mφs) and were phenotypically characterized using qPCR, western blot, and ELISA. To analyze the therapeutic potential, the IL-13 Mφs were intraspinally injected at the perilesional area after hemisection SCI in female mice. Functional recovery and histopathological improvements were evaluated using the Basso Mouse Scale score and immunohistochemistry. Neuroprotective effects of IL-13 were investigated using different cell viability assays in murine and human neuroblastoma cell lines, human neurospheroids, as well as murine organotypic brain slice cultures. In contrast to Mφs prestimulated with recombinant IL-13, perilesional transplantation of IL-13 Mφs promoted functional recovery following SCI in mice. This improvement was accompanied by reduced lesion size and demyelinated area. The local anti-inflammatory shift induced by IL-13 Mφs resulted in reduced neuronal death and fewer contacts between dystrophic axons and Mφs/microglia, suggesting suppression of axonal dieback. Using IL-4Rα-deficient mice, we show that IL-13 signaling is required for these beneficial effects. Whereas direct neuroprotective effects of IL-13 on murine and human neuroblastoma cell lines or human neurospheroid cultures were absent, IL-13 rescued murine organotypic brain slices from cell death, probably by indirectly modulating the Mφ/microglia responses. Collectively, our data suggest that the IL-13-induced anti-inflammatory Mφ/microglia phenotype can preserve neuronal tissue and ameliorate axonal dieback, thereby promoting recovery after SCI.

After spinal cord injury, macrophages can exert either beneficial or detrimental effects depending on their phenotype. Aside from their critical role in inflammatory responses, macrophages are also specialized in the recognition, engulfment, and degradation of pathogens, apoptotic cells, and tissue debris. They promote remyelination and axonal regeneration by removing inhibitory myelin components and cellular debris. However, excessive intracellular presence of lipids and dysregulated intracellular lipid homeostasis result in the formation of foamy macrophages. These develop a pro-inflammatory phenotype that may contribute to further neurological decline. Additionally, myelin-activated macrophages play a crucial role in axonal dieback and retraction. Here, we review the opposing functional consequences of phagocytosis by macrophages in spinal cord injury, including remyelination and regeneration versus demyelination, degeneration, and axonal dieback. Furthermore, we discuss how targeting the phagocytic ability of macrophages may have therapeutic potential for the treatment of spinal cord injury.

Traumatic spinal cord injury (SCI) results in complex neurological dysfunction. Astrocytes react in response to SCI by undergoing proliferation and migrating to the injury site, resulting in astrogliosis. Neural stem cells (NSCs) have been proposed as a promising therapeutic strategy to promote neurogenesis following transplantation post SCI. In this study the antigenic and morphological phenotype of astrocytes, and the pattern of galectin expression was examined following SCI. Female Sprague Dawley rats were contused at thoracic (T) level T9 and treated with Cyclosporin-A (CsA) and/or NSCs 1 week post-injury. CsA and NSC treatment led to increased glial fibrillary acidic protein (GFAP), brain lipid binding protein (BLBP) and vimentin expression. Quiescent and reactive astrocytes were the most abundant cell morphology observed. Astrocytes co-localised with galectin-1 (Gal-1) and galectin-3 (Gal-3). Gal-1 expression was increased in both CsA and CSA + NSC treated animals 2 weeks post-treatment. Treatment with CsA and/or NSCs offers many prospective beneficial effects. A detailed revelation of how astrocytes are heterogeneously responsive to SCI, in addition to their affinity to galectins and response to CsA and NSCs is shown in this study. The current study’s findings support the potential application of NSCs as a novel therapeutic tool in the treatment of SCI.

Spinal cord injury (SCI) triggers the formation of a glial and fibrotic scar, which creates a major barrier for neuroregenerative processes. Previous findings indicate that mast cells (MCs) protect the spinal cord after mechanical damage by suppressing detrimental inflammatory processes via mouse mast cell protease 4 (mMCP4), a MC-specific chymase. In addition to these immunomodulatory properties, mMCP4 also plays an important role in tissue remodeling and extracellular matrix degradation. Therefore, we have investigated the effects of mMCP4 on the scarring response after SCI. We demonstrate that the decrease in locomotor performance in mMCP4−/− mice is correlated with excessive scar formation at the lesion. The expression of axon-growth inhibitory chondroitin sulfate proteoglycans was dramatically increased in the perilesional area in mMCP4−/− mice compared to wild type mice. Moreover, the fibronectin-, laminin-, and collagen IV-positive scar was significantly enlarged in mMCP4−/− mice at the lesion center. A degradation assay revealed that mMCP4 directly cleaves collagen IV in vitro. On the gene expression level, neurocan and GFAP were significantly higher in the mMCP4−/− group at day 2 and day 28 after injury respectively. In contrast, the expression of fibronectin and collagen IV was reduced in mMCP4−/− mice compared to WT mice at day 7 after SCI. In conclusion, our data show that mMCP4 modulates scar development after SCI by altering the gene and protein expression patterns of key scar factors in vivo. Therefore, we suggest a new mechanism via which endogenous mMCP4 can improve recovery after SCI.

A mounting body of evidence suggests that stress plays a major role in the injury progression after spinal cord injury (SCI). Injury activates the stress systems; this in turn may augment the generation of pro-inflammatory cytokines, stimulate pro-inflammatory immune cells, and alter the balance between the pro- and anti-inflammatory immune response. As a result, it is suggested that stress pathways may augment neuronal damage and loss after SCI. Considering these potential detrimental effects of stress after SCI, we hypothesized that inhibition of stress pathways immediately after SCI may offer protection from damage and improve recovery. To investigate the relevance of stress responses in SCI recovery, we investigated the effects of blocking three well-studied stress response axes in a mouse model of SCI. Propranolol, RU-486, and CP-99994 were administered to inhibit the sympathetic axis, the hypothalamus-pituitary-adrenal axis, and the neuropeptide axis, respectively. Surprisingly, assessing functional recovery by the Basso Mouse Scale revealed that RU-486 and CP-99994 did not affect functional outcome, indicating that these pathways are dispensable for neuroprotection or repair after SCI. Moreover, the beta-blocker propranolol worsened functional outcome in the mouse SCI model. In conclusion, immediate inhibition of three major stress axes has no beneficial effects on functional recovery after SCI in mice. These results suggest that injury-induced stress responses do not interfere with the healing process and hence, pharmacological targeting of stress responses is not a recommended treatment option for SCI. These findings are of great importance for other researchers to avoid unnecessary and potentially futile animal experiments.

A disintegrin and metalloproteinase 17 (ADAM17) is the major sheddase involved in the cleavage of a plethora of cytokines, cytokine receptors and growth factors, thereby playing a substantial role in inflammatory and regenerative processes after central nervous system trauma. By making use of a hypomorphic ADAM17 knockin mouse model as well as pharmacological ADAM10/ADAM17 inhibitors, we showed that ADAM17-deficiency or inhibition significantly increases clearance of apoptotic cells, promotes axon growth and improves functional recovery after spinal cord injury (SCI) in mice. Microglia-specific ADAM17-knockout (ADAM17flox+/+-Cx3Cr1 Cre+/-) mice also showed improved functional recovery similar to hypomorphic ADAM17 mice. In contrast, endothelial-specific (ADAM17flox+/+-Cdh5Pacs Cre+/-) and macrophage-specific (ADAM17flox+/+-LysM Cre+/-) ADAM17-knockout mice or bone marrow chimera with transplanted ADAM17-deficient macrophages, displayed no functional improvement compared to wild type mice. These data indicate that ADAM17 expression on microglia cells (and not on macrophages or endothelial cells) plays a detrimental role in inflammation and functional recovery after SCI.

After spinal cord injury (SCI), monocyte derived macrophages play a detrimental role. Histone deacetylases (HDACs) are central epigenetic regulators of macrophage-polarization. We hypothesized that HDAC3 inhibition suppresses the pro-inflammatory macrophage phenotype (M1), promotes the anti-inflammatory phenotype (M2) and improves functional recovery after SCI. Therefore, two inhibitors of HDAC3 were selected, namely scriptaid and RGFP966. The impact on macrophage polarization was studied by investigating the effect on gene and protein expression of selected M1 and M2 markers. We show that scriptaid differentially influences M1 and M2 markers. It increases CD86 and iNOS gene expression and decreases GPR18, CD38, FPR2 and Arg-1 gene expression as well as the production of IL-6 and NO. RGFP966 primarily increased the expression of the M2 markers Arg-1 and Ym1 and reduced the production of IL-6 (M1). RGFP966 and scriptaid reduced the formation of foamy macrophages. Finally, to investigate the impact of HDAC3 inhibition on functional recovery after SCI, we studied the effects of RGFP966 and scriptaid in an in vivo T-cut hemisection SCI model. Histological analyses were performed on spinal cord sections to determine lesion size and astrogliosis, demyelinated area and selected infiltrating immune cells. RGFP966 and scriptaid did not affect functional recovery or histopathological outcome after SCI. In conclusion, these results indicate that specific HDAC3 inhibition with RGFP966 promotes alternative activation of macrophages and reduces the formation of foamy macrophages, but does not lead to a better functional recovery after SCI.

Current therapies for treating antineutrophil cytoplasm autoantibody (ANCA)-associated vasculitis include cyclophosphamide and corticosteroids. Unfortunately, these agents are associated with severe adverse effects, despite inducing remission in most patients. Histone deacetylase inhibitors are effective in rodent models of inflammation and act synergistically with many pharmacological agents, including alkylating agents like cyclophosphamide. EDO-S101 is an alkylating fusion histone deacetylase inhibitor molecule combining the DNA alkylating effect of Bendamustine with a pan-histone deacetylase inhibitor, Vorinostat. Here we studied the effects of EDO-S101 in two established rodent models of ANCA-associated vasculitis: a passive mouse model of anti-myeloperoxidase IgG-induced glomerulonephritis and an active rat model of myeloperoxidase-ANCA microscopic polyangiitis. Although pretreatment with EDO-S101 reduced circulating leukocytes, it did not prevent the development of passive IgG-induced glomerulonephritis in mice. On the other hand, treatment in rats significantly reduced glomerulonephritis and lung hemorrhage. EDO-S101 also significantly depleted rat B and T cells, and induced DNA damage and apoptosis in proliferating human B cells, suggesting a selective effect on the adaptive immune response. Thus, EDO-S101 may have a role in treatment of ANCA-associated vasculitis, operating primarily through its effects on the adaptive immune response to the autoantigen myeloperoxidase.

Animal models with constant, long-lasting motor deficits together with the right tests to assess behavioral abnormalities are needed to study the effectiveness of potential therapies to restore motor functions. In the current study, controlled cortical impact (CCI) was applied in rats to induce damage to the forelimb area of the motor cortex and the dorsal striatum. Motor behavior was assessed before and after CCI, using fine motor skill tests such as the adhesive removal test, the cylinder test, and the Montoya staircase test as well as the automated gait analysis system CatWalk XT over a 6 week period. CCI caused a variety of unilateral motor deficits, which were characterized in detail by using the selected fine motor skill tests. In striking contrast to previous studies on CCI in mice, neither forelimb impairments, nor general changes in gait, were detected with the CatWalk XT. These data suggest that the adhesive removal test, the cylinder test, and the Montoya staircase test are the methods of choice to detect long-term unilateral motor deficits in rats after CCI, whereas the use of automated gait analysis systems might not be suitable to measure these behavioral deviations.