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Background: Glioblastoma (GBM) is the deadliest of brain tumors. Standard treatment for GBM is surgery, followed by combined radiation therapy and chemotherapy. Current therapy prolongs survival but does not offer a cure. We report on a novel immunotherapy against GBM, tested in an animal model of C57BL/6 mice injected intra-cranially with a lethal dose of murine GL261 glioma cells.Methods: Ten week-old C57BL/6 mice were anesthetized before injection of 2 × 10(4) GL261 cells in the right cerebral hemisphere and after 3 days half of the mice were administered a single subcutaneous (s.c.) injection of irradiated semi-allogeneic vaccine, while mock-vaccinated mice received a s.c. injection of phosphate-buffered saline (PBS). Tumor engraftment was monitored through bioluminescence imaging (BLI). Length of animal survival was measured by Kaplan-Meier graphs and statistics. At time of sacrifice brain tissue was processed for estimation of tumor size and immunohistochemical studies.Results: Overall survival of vaccinated mice was significantly longer compared to mock-vaccinated mice. Five to ten percent of vaccinated mice survived more than 90 days following the engraftment of GL261 cells in the brain and appeared to be free of disease by BLI. Tumor volume in the brain of vaccinated mice was on average five to ten-fold smaller compared to mock-vaccinated mice. In vaccinated mice, conspicuous microglia infiltrates were observed in tumor tissue sections and activated microglia appeared to form a fence along the perimeter of the tumor cells. The results of these animal studies persuaded the Office of Orphan Products Development of the Food and Drug Administration (FDA) to grant Orphan Drug Designation for treatment of GBM with irradiated, semi-allogeneic vaccines.Conclusions: Our preclinical observations suggest that semi-allogeneic vaccines could be tested clinically on subjects with GBM, as an adjuvant to standard treatment. [ABSTRACT FROM AUTHOR]

Background: Experimental results from studies with inbred mice and their syngeneic tumors indicated that the inoculation of semi-allogeneic cell hybrids (derived from the fusion between syngeneic tumor cells and an allogeneic cell line) protects the animal host from a subsequent lethal challenge with unmodified syngeneic tumor cells. Methods: Semi-allogeneic somatic cell hybrids were generated by the fusion of EL-4 T lymphoma cells (H-2b) and BALB/c-derived renal adenocarcinoma RAG cells (H-2d). Cell hybrids were injected intra-peritoneally (i.p.) in C57BL/6 mice (H-2b) before challenging the mice with a tumorigenic dose of EL-4 cells. Results: Semi-allogeneic tumor cell hybrids could not form a tumor in the animal host because they expressed allogeneic determinants (H-2d) and were rejected as a transplant. However, they conferred protection against a tumorigenic challenge of EL-4 cells compared to control mice that were mock-vaccinated with i.p.-injected phosphate-buffered saline (PBS) and in which EL-4 lymphomas grew rapidly to a large size in the peritoneal cavity. Screening of spleen-derived RNA by means of focused microarray technology revealed up-regulation of genes involved in the Th-1- type immune response and in the activation of dendritic antigen-presenting cells (APC). Conclusion: The results of our studies are entirely consistent with the concept that CD80- and CD86-expressing APC play a central role in mediating the immune protection induced by semiallogeneic vaccines by activating a Th-1 response and instructing T cells responsible for killing autologous tumor cells. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Background: Amyotrophic lateral sclerosis (ALS) is currently an incurable disease without highly effective pharmacological treatments. The peptide drug GM604 (GM6 or Alirinetide) was developed as a candidate ALS therapy, which has demonstrated safety and good drug-like properties with a favorable pharmacokinetic profile. GM6 is hypothesized to bolster neuron survival through the multi-target regulation of developmental pathways, but mechanisms of action are not fully understood. Methods: This study used RNA-seq to evaluate transcriptome responses in SH-SY5Y neuroblastoma cells following GM6 treatment (6, 24 and 48 h). Results: We identified 2867 protein-coding genes with expression significantly altered by GM6 (FDR < 0.10). Early (6 h) responses included up-regulation of Notch and hedgehog signaling components, with increased expression of developmental genes mediating neurogenesis and axon growth. Prolonged GM6 treatment (24 and 48 h) altered the expression of genes contributing to cell adhesion and the extracellular matrix. GM6 further down-regulated the expression of genes associated with mitochondria, inflammatory responses, mRNA processing and chromatin organization. GM6-increased genes were located near GC-rich motifs interacting with C2H2 zinc finger transcription factors, whereas GM6-decreased genes were located near AT-rich motifs associated with helix-turn-helix homeodomain factors. Such motifs interacted with a diverse network of transcription factors encoded by GM6-regulated genes (STAT3, HOXD11, HES7, GLI1). We identified 77 ALS-associated genes with expression significantly altered by GM6 treatment (FDR < 0.10), which were known to function in neurogenesis, axon guidance and the intrinsic apoptosis pathway. Conclusions: Our findings support the hypothesis that GM6 acts through developmental-stage pathways to influence neuron survival. Gene expression responses were consistent with neurotrophic effects, ECM modulation, and activation of the Notch and hedgehog neurodevelopmental pathways. This multifaceted mechanism of action is unique among existing ALS drug candidates and may be applicable to multiple neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Background: Complement promotes neuroinflammation and injury in models of stroke. However, complement is also being increasingly implicated in repair and regeneration after central nervous system (CNS) injury, and some complement deficiencies have been shown to provide acute, but not subacute, protection after murine stroke. Here, we investigate the dual role of complement in injury and repair after cerebral ischemia and reperfusion.Methods: We used complement-deficient mice and different complement inhibitors in a model of transient middle cerebral artery occlusion to investigate complement-dependent cellular and molecular changes that occur through the subacute phase after stroke.Results: C3 deficiency and site-targeted complement inhibition with either CR2-Crry (inhibits all pathways) or CR2-fH (inhibits alternative pathway) significantly reduced infarct size, reduced apoptotic cell death, and improved neurological deficit score in the acute phase after stroke. However, only in CR2-fH-treated mice was there sustained protection with no evolution of injury in the subacute phase. Whereas both inhibitors significantly reduced microglia/macrophage activation and astrogliosis in the subacute phase, only CR2-fH improved neurological deficit and locomotor function, maintained neurogenesis markers, enhanced neuronal migration, and increased VEGF expression. These findings in CR2-fH-treated mice correlated with improved performance in spatial learning and passive avoidance tasks. The complement anaphylatoxins have been implicated in repair and regenerative mechanisms after CNS injury, and in this context CR2-fH significantly reduced, but did not eliminate the generation of C5a within the brain, unlike CR2-Crry that completely blocked C5a generation. Gene expression profiling revealed that CR2-fH treatment downregulated genes associated with apoptosis, TGFβ signaling, and neutrophil activation, and decreased neutrophil infiltration was confirmed by immunohistochemistry. CR2-fH upregulated genes for neural growth factor and mediators of neurogenesis and neuronal migration. Live animal imaging demonstrated that following intravenous injection, CR2-fH targeted specifically to the post-ischemic brain, with a tissue half-life of 48.5 h. Finally, unlike C3 deficiency, targeted complement inhibition did not increase susceptibility to lethal post-stroke infection, an important consideration for stroke patients.Conclusions: Ischemic brain tissue-targeted and selective inhibition of alternative complement pathway provide self-limiting inhibition of complement activation and reduces acute injury while maintaining complement-dependent recovery mechanisms into the subacute phase after stroke. [ABSTRACT FROM AUTHOR]

Background: Repetitive mild traumatic brain injuries (rmTBI) are associated with cognitive deficits, inflammation, and stress-related events. We tested the effect of nutrient intake on the impact of rmTBI in an animal model of chronic traumatic encephalopathy (CTE) to study the pathophysiological mechanisms underlying this model. We used a between group design rmTBI closed head injuries in mice, compared to a control and nutrient-treated groups.Methods: Our model allows for controlled, repetitive closed head impacts to mice. Briefly, 24-week-old mice were divided into five groups: control, rmTBI, and rmTBI with nutrients (2% of NF-216, NF-316 and NF-416). rmTBI mice received four concussive impacts over 7 days. Mice were treated with NutriFusion diets for 2 months prior to the rmTBI and until euthanasia (6 months). Mice were then subsequently euthanized for macro- and micro-histopathologic analysis for various times up to 6 months after the last TBI received. Animals were examined behaviorally, and brain sections were immunostained for glial fibrillary acidic protein (GFAP) for astrocytes, iba-1 for activated microglia, and AT8 for phosphorylated tau protein.Results: Animals on nutrient diets showed attenuated behavioral changes. The brains from all mice lacked macroscopic tissue damage at all time points. The rmTBI resulted in a marked neuroinflammatory response, with persistent and widespread astrogliosis and microglial activation, as well as significantly elevated phospho-tau immunoreactivity to 6 months. Mice treated with diets had significantly reduced inflammation and phospho-tau staining.Conclusions: The neuropathological findings in the rmTBI mice showed histopathological hallmarks of CTE, including increased astrogliosis, microglial activation, and hyperphosphorylated tau protein accumulation, while mice treated with diets had attenuated disease process. These studies demonstrate that consumption of nutrient-rich diets reduced disease progression. [ABSTRACT FROM AUTHOR]

Experimental results from studies with inbred mice and their syngeneic tumors indicated that the inoculation of semi-allogeneic cell hybrids (derived from the fusion between syngeneic tumor cells and an allogeneic cell line) protects the animal host from a subsequent lethal challenge with unmodified syngeneic tumor cells. Semi-allogeneic somatic cell hybrids were generated by the fusion of EL-4 T lymphoma cells (H-2b) and BALB/c-derived renal adenocarcinoma RAG cells (H-2d). Cell hybrids were injected intra-peritoneally (i.p.) in C57BL/6 mice (H-2b) before challenging the mice with a tumorigenic dose of EL-4 cells. Semi-allogeneic tumor cell hybrids could not form a tumor in the animal host because they expressed allogeneic determinants (H-2d) and were rejected as a transplant. However, they conferred protection against a tumorigenic challenge of EL-4 cells compared to control mice that were mock-vaccinated with i.p.-injected phosphate-buffered saline (PBS) and in which EL-4 lymphomas grew rapidly to a large size in the peritoneal cavity. Screening of spleen-derived RNA by means of focused microarray technology showed up-regulation of genes involved in the Th-1-type immune response and in the activation of dendritic antigen-presenting cells (APC). The results of our studies confirm the role of APC in mediating the immune protection induced by semi-allogeneic vaccines by activating a Th-1 response; these studies also reveal that semi-allogeneic vaccines are able to interfere with or even block the tumor-mediated induction of immune tolerance, a key mechanism underlying the suppression of anti-tumor immunity in the immune competent host. [ABSTRACT FROM AUTHOR]