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AUMsilence sdASO platform in neuroscience and neurodegeneration research

Published applications in neurobiology and neurodegenerative disease

Domain
Neuroscience and neurodegeneration
References
8

Executive summary

Peer-reviewed publications have used AUM BioTech's self-delivering antisense oligonucleotide (AUMsilence sdASO) technology in neuroscience and neurodegeneration. AUM BioTech's AUMsilence sdASO platform enables mRNA knockdown without transfection reagents, addressing critical limitations of conventional gene silencing approaches including siRNA and CRISPR for basic and translational research.
Key findings demonstrate cellular delivery in primary neurons, in glial cells and in acute brain slices, in every case without a transfection reagent. In the studies reviewed here, AUMsilence sdASO entered cultured cortical neurons and silenced their target gene to different extents across five sequences1; reduced a chemokine transcript in injured mouse spinal cord by approximately 60% after three intrathecal doses3; and, as AUMantagomir sdASO, knocked a microRNA down by approximately 80% in acute hippocampal slices at 1 μM4. The technology has been successfully applied in Alzheimer's disease and tauopathy research, spinal cord injury models, glioblastoma studies, and neuroinflammation investigations. The gymnotic uptake mechanism of these chemically modified oligonucleotides eliminates the need for viral vectors or lipid nanoparticles, enabling application in both in vitro and in vivo neuroscience research.

1. Introduction: Gene silencing in neuroscience research

1.1 Current challenges in gene silencing research tools

Gene silencing technologies are essential tools for understanding neurobiology, neurodegenerative disease mechanisms, and developing new investigational approaches. However, conventional methods face significant technical limitations that restrict their utility in basic and translational neuroscience research. These limitations become particularly apparent when working with primary neuronal cultures, organotypic slice preparations, and in vivo models of neurological disease.

siRNA limitations in research

  • Requires transfection reagents introducing cellular toxicity, particularly problematic in sensitive primary neurons where lipid-based reagents can trigger apoptotic pathways
  • Poor uptake in primary neurons and glial cells, and dependence on RISC loading for activity
  • Limited penetration in 3D culture systems and organoids where diffusion barriers and extracellular matrix restrict access
  • Off-target effects through seed sequence matching, complicating phenotypic data interpretation
  • Rapid degradation by endogenous RNases requiring repeated treatments, compounding toxicity issues
  • Variable efficiency across different cell types necessitating extensive protocol optimization

CRISPR challenges for functional studies

  • Permanent genetic modifications limiting reversibility for temporal gene function studies and dose-response experiments
  • Potential off-target mutagenesis at sites with guide RNA sequence similarity, confounding phenotype interpretation
  • Significant delivery barriers requiring viral vectors (biosafety concerns, extended culture periods) or electroporation (cellular stress)
  • Time-intensive protocol development for a stable knockout, where a knockdown is transient and needs none
  • Variable editing efficiency across cell types and genomic loci, with some targets refractory to editing
  • Immune responses to Cas9 protein in immunocompetent models confounding in vivo studies

Delivery barrier in primary cells

  • Primary cell types are difficult to transfect with conventional methods, creating a fundamental bottleneck for functional genomics
  • Transfection reagent toxicity in sensitive neuronal cells, where cationic lipids can trigger stress responses and alter gene expression
  • Electroporation can cause cellular stress through membrane disruption, with altered phenotypes persisting afterwards
  • Viral vectors require extended culture periods, raise biosafety concerns, and can trigger innate immune responses
  • Nanoparticle formulations show lysosomal sequestration, reducing cargo bioavailability and limiting functional knockdown

Key challenge

Delivery, not mechanism of action, represents the primary technical barrier limiting gene silencing research in neuroscience. Primary cell types resist conventional transfection methods, creating fundamental limitations for functional genomics and translational research. This delivery challenge is particularly acute in post-mitotic neurons, where cellular stress responses are easily triggered.

1.2 Gene silencing requirements for neuroscience research

Neuroscience research requires gene silencing tools that can effectively function across a diverse range of experimental systems. Primary neurons, including cortical neurons, hippocampal neurons, dopaminergic neurons, and motor neurons, represent critical models for studying neuronal function and disease mechanisms but are difficult to transfect. Glial cells, including astrocytes, microglia, and oligodendrocytes, play essential roles in neuroinflammation and neurodegenerative disease but exhibit variable transfection efficiency. Tumor cells such as glioblastoma, neuroblastoma, and medulloblastoma require effective gene silencing tools for target validation studies. Difficult-to-transfect cell lines, including neuronal cell lines and suspension cultures, often resist conventional transfection methods. In vivo research models, including transgenic mice, disease models, and orthotopic brain tumor models, require delivery methods that can cross the blood-brain barrier or be administered directly to the CNS. Patient-derived samples, including primary tumor cells and patient-derived xenografts, represent clinically relevant models but are often refractory to standard transfection protocols.

2. AUMsilence sdASO platform

2.1 Technology overview

AUM BioTech's AUMsilence self-delivering antisense oligonucleotides (sdASOs) carry a dual modification system. This system combines sugar modifications with phosphorothioate backbone linkages and other stabilizing chemical modifications. The sugar modifications enhance binding affinity to target mRNA while maintaining RNase H1 recruitment capability, while the phosphorothioate linkages provide nuclease resistance and enable protein binding that facilitates cellular uptake. This design enables direct cellular uptake through gymnotic delivery without transfection reagents while maintaining high target specificity and knockdown activity for research applications. The single-stranded nature of these oligonucleotides allows for precise targeting through Watson-Crick base pairing, requiring perfect complementarity over the entire binding site and thereby minimizing off-target effects compared to siRNA-based approaches.

The mechanism of action relies on RNase H1-mediated catalytic degradation of target mRNA. Upon binding to complementary mRNA sequences, the DNA-RNA heteroduplex recruits endogenous RNase H1 enzyme, which cleaves the RNA strand. This catalytic mechanism means that a single ASO can mediate the degradation of multiple mRNA copies, contributing to the knockdown observed in functional studies. The chemical modifications are strategically positioned to maintain the DNA-like character of the central region necessary for RNase H1 recognition while providing stability at the termini where exonuclease degradation typically initiates.

Self-delivery for research

Gymnotic uptake eliminates the need for transfection reagents, viral vectors, or lipid nanoparticles. The phosphorothioate backbone modifications let the oligonucleotides bind proteins on the cell surface, and they are taken up by endocytosis. Addition to culture medium or injection into animal models enables cellular internalization without a delivery vehicle.

RNase H1 mechanism

Forms stable DNA-RNA hybrids that recruit endogenous RNase H1 enzyme for catalytic mRNA degradation. The enzyme cleaves the RNA strand within the heteroduplex, releasing the ASO to bind further target transcripts. This catalytic mechanism means that a single ASO can degrade multiple target mRNA copies, contributing to sustained knockdown with relatively low intracellular concentrations.

Enhanced stability for in vivo research

Chemical modifications provide nuclease resistance, enabling an extended duration of action and in vivo research applications without complex formulations. The phosphorothioate backbone provides resistance to both exonucleases and endonucleases, while sugar modifications protect against RNase degradation. This stability profile reduces the frequency of administration in chronic studies.

Specificity

Single-stranded mechanism requires perfect complementarity over the entire binding site, minimizing off-target effects. Unlike siRNAs, which can exhibit microRNA-like off-target effects through seed sequence matching (positions 2-8 of the guide strand), ASOs require full-length complementarity for stable binding and RNase H1 recruitment. This specificity reduces the need for extensive off-target validation and provides cleaner phenotypic data.

2.2 Product platforms for research

Product platforms for research
ProductTarget RNA classResearch applications
AUMsilence sdASOProtein-coding mRNAsGene knockdown studies, functional genomics, pathway analysis, target validation in disease models
AUMantagomir sdASOmicroRNAsmicroRNA inhibition, regulatory network studies, disease modeling, synaptic plasticity research
AUMlnc sdASOLong non-coding RNAslncRNA functional studies, epigenetic regulation research, nuclear RNA targeting, chromatin biology

3. Self-delivery technology and cellular uptake

3.1 Cellular uptake in primary neurons

A key feature of AUMsilence sdASO is its ability to penetrate challenging cell types without assistance from delivery vehicles. This is particularly useful in neuroscience, where primary neurons and glial cells are sensitive to transfection reagents. The uptake relies on the phosphorothioate backbone, which lets the oligonucleotides bind proteins on the cell surface; they are then taken up by endocytosis.
In a study investigating the role of TRIM11 in tauopathies published in Science, AUMsilence sdASO designed to silence the Trim11 gene were shown to effectively enter cultured primary cortical neurons1. The study reports that the oligonucleotides entered the neurons and silenced the target gene to different extents across the five sequences tested, demonstrating that the self-delivering chemistry is effective in primary, post-mitotic neuronal cultures. The authors noted that these AUMsilence sdASOs effectively entered cultured neurons without requiring transfection reagents, a critical enabling feature for functional genomics in neurobiology. Supplementary figure S12 records that comparison: a scrambled control beside the TRIM11 sequences in wild-type cortical neurons, treated for three days. The study reports no dose series for these oligonucleotides and no analysis of the route by which they were taken up.
In acute hippocampal slices, AUMantagomir sdASO targeting miR-134-5p were applied via bath application at 1 μM concentration for 3 hours4. The rapid functional effects observed in electrophysiological recordings suggest efficient penetration into the tissue and uptake by neurons within the slice preparation. The authors noted direct incorporation of miR-134 antagomirs into the acute hippocampal neurons based on the rapid rescue of long-term potentiation deficits. This application demonstrates that AUMantagomir sdASO can penetrate complex tissue preparations where diffusion barriers and extracellular matrix components typically limit the effectiveness of conventional transfection-based approaches.
Cellular uptake across neuronal preparations
Cell typeAUM productDelivery methodUptake evidenceReference
Primary cortical neurons (wild type and PS19)AUMsilence sdASODirect addition to culture mediumTarget gene silenced to different extents across five sequences, without transfection reagents[1]
Acute hippocampal slicesAUMantagomir sdASOBath application (1 μM, 3 hours)Rapid functional effects in electrophysiology, direct neuronal incorporation[4]
Glioblastoma cells (U87-MG and two patient-derived lines)AUMsilence sdASODirect addition to the well (10 μM, 42 hours), with no medium changeNR4A2 expression reduced in all three lines by Western blot[2]
Injured mouse spinal cord (in vivo)AUMsilence sdASOLumbar intrathecal injection (10 mg/kg)Present at the lesion site in CD11b+ macrophages and microglia and GFAP+ astrocytes; no uptake detected in NeuN+ neurons[3]

4. Knockdown in neurological disease models

AUMsilence sdASO silences target genes across a range of models relevant to neuroscience, from cancer cell lines to primary neurons modeling neurodegenerative diseases. RNase H1 cleavage is catalytic, so one oligonucleotide can cut more than one copy of the target, and the chemical modifications resist nucleases. The catalytic nature of RNase H1-mediated degradation means that relatively low intracellular concentrations of ASO can achieve substantial knockdown, as each ASO can mediate the degradation of multiple target mRNA copies.

4.1 TRIM11 in Alzheimer's disease models

In the study published in Science, AUMsilence sdASO targeting Trim11 were used to validate the part played by TRIM11 protein in tau pathology1. Five sequences against different regions of the Trim11 mRNA were tested in cultured cortical neurons, where they entered the cells without a transfection reagent and silenced TRIM11 expression to different extents (supplementary figure S12). The study reports no knockdown percentage for any of the five, and no dose series for any of them.
Two separate experiments followed, and the study keeps them apart. Primary cortical neurons from PS19 transgenic mice, which express the human tau P301S mutation, were challenged with preformed fibrils (PFFs) of a truncated tau protein carrying the P301L mutation; silencing Trim11 exacerbated tau aggregation, increasing tau reactive to the AT8 antibody (recognizing phosphorylated tau at Ser202/Thr205) and to MC1 (recognizing a disease-specific conformation of tau) by approximately 50 to 90%, quantified by immunofluorescence. Separately, in wild-type cortical neurons and with no fibril challenge, silencing TRIM11 reduced presynaptic synaptophysin-positive puncta by approximately 40% and postsynaptic PSD95-positive puncta by approximately 30%, and lowered neurofilament light chain by approximately 40% while leaving MAP2 unchanged. It also reduced neuronal viability, and the size of that reduction tracked how far each sequence had lowered TRIM11 expression. That correlation across sequences, rather than a dose series, is the evidence the study offers that the effect follows from the loss of TRIM11. This loss-of-function approach using AUMsilence sdASO was critical for establishing causality, as it demonstrated that reducing TRIM11 levels was sufficient to worsen tau pathology.

4.2 CCL3 in spinal cord injury

In a mouse model of spinal cord injury (SCI), AUMsilence sdASO targeting CCL3 (C-C motif chemokine ligand 3) suppressed CCL3 in the injured spinal cord3. Four sequences were screened first in cultured bone marrow-derived macrophages stimulated with lipopolysaccharide, where the labeled oligonucleotide had entered the cells within 2 hours of being added to the medium, and one of the four reduced CCL3 expression by approximately 80% while the other three produced no significant change; that sequence was used for every experiment that followed. In vivo, a moderate contusion was induced at the T11 thoracic level using the Infinite Horizon impactor device at a contusion force of 40 kdyn, and the oligonucleotide was given by lumbar intrathecal injection at 10 mg/kg.
How long suppression lasted depended on how many doses were given. A single injection significantly suppressed CCL3 mRNA in the injured spinal cord at day 3, along with TNF and IL-1β transcripts, but the study reports that this effect was not sustained beyond day 3. Two injections, given immediately after injury and 24 hours later, again suppressed all three transcripts at day 3 only. Three injections, given every 24 hours for 3 days, produced sustained suppression at day 7, reducing CCL3 by approximately 60%, with TNF and IL-1β reduced by approximately 50%. In the discussion the authors give the reduction in the injured tissue as 50-60% at day 3 and as 62% at day 7 after the third dose. Suppression of CCL3 was confirmed at the protein level by ELISA, and TNF protein was reduced at days 1 and 3 but had returned to baseline by day 7. CCL3 was measured at days 1, 3 and 7; the study reports no later measurement of it.

4.3 NR4A2 in glioblastoma

In glioblastoma research, AUMsilence sdASO targeting NR4A2 (nuclear receptor subfamily 4 group A member 2) knocked the receptor down in one established cell line, U87-MG, and in two patient-derived glioblastoma cell lines, 15037 and 14015s, all three grown in culture2. The study employed two independent ASO sequences added directly to the wells to give a final concentration of 10 μM. For the siRNA arm the culture medium was changed; for the antisense oligonucleotides it was not, which is the study's own description of the difference between the two. Cells were transfected for 42 hours.
Western blot analysis confirmed reduced NR4A2 expression in all three lines, and this was accompanied by decreased cell proliferation and decreased invasion in a Boyden chamber assay with Matrigel-coated membranes, each measured against a non-specific control oligonucleotide at a significance threshold of p < 0.05. The study reports no knockdown percentage for either sequence. Apoptosis was read out by Annexin V staining and by Western blot for cleaved caspase 8, caspase 7 and PARP (poly ADP-ribose polymerase); the study notes twice that caspase 8 cleavage was not observed in 15037 cells, so that marker rose in two of the three lines. A three-dimensional tumor spheroid assay showed that knocking NR4A2 down inhibited invasion out of the spheroid in 15037 cells, which the study records as the only one of the three lines that invaded in that assay.
On the comparison with siRNA the study is brief and shows no data. It opens its results by writing that Initial studies showed that small interfering RNAs (siRNAs) were less effective than antisense oligonucleotides (AsOs) for NR4A2 knockdown, referring to work done before this one, and it presents no figure comparing the two and gives no reason for the difference.

4.4 miR-134-5p in synaptic plasticity

AUMantagomir sdASO targeting miR-134-5p were used to rescue synaptic plasticity deficits in an Aβ(1-42)-induced model of Alzheimer's disease4. Acute hippocampal slices (400 μm thick) from adult male Wistar rats were treated with 200 nM Aβ(1-42) oligomers for 3 hours, which impaired late long-term potentiation (late LTP) while leaving early LTP intact, and left the slices unable to express synaptic tagging and capture (STC). The same treatment raised miR-134-5p in the slices about 3.5-fold over untreated control slices. Co-treatment with 1 μM miR-134-5p antagomir for 3 hours via bath application rescued both deficits. The study recorded field excitatory postsynaptic potentials (fEPSPs) from the CA1 region of the hippocampus using a two-pathway experimental design. Late-phase LTP was induced by strong tetanic stimulation (STET: three trains of 100 pulses at 100 Hz), while early-phase LTP was induced by weak tetanic stimulation (WTET: single train of 21 pulses at 100 Hz). Four inhibitor constructs were tested, and the one used here is the one that showed the maximum knockdown efficiency, approximately 80% of miR-134-5p at 1 μM by quantitative RT-PCR, with concurrent upregulation of CREB-1 and BDNF at both mRNA and protein levels. Western blot analysis showed increased levels of total CREB, phosphorylated CREB (p-CREB), pro-BDNF, and mature BDNF in antagomir-treated slices. The rescue of LTP was protein synthesis-dependent, as demonstrated by blockade with anisomycin at 25 μM and emetine at 20 μM, and NMDA receptor-dependent, as shown by blockade with AP5 at 50 μM. In aged C57BL/6J mice (16-18 months old), four of these findings were repeated: the rise in miR-134-5p under Aβ(1-42), the knockdown, the increase in CREB-1 and BDNF messenger RNA, and the rescue of late LTP. Synaptic tagging and capture was not tested in those mice and no western blot was run on them, so the tagging and capture result stands in the rat alone. The rapid functional effects (observable within hours) suggest efficient penetration of the AUMantagomir sdASO into the slice tissue and uptake by neurons, a significant advantage over viral vector approaches that require days for expression.
Knockdown in neurological disease models
Target geneCell type or modelProduct and dosingKnockdownKey findingRef
TRIM11Primary cortical neurons (wild type and PS19)AUMsilence sdASO, five sequencesSilenced to different extents; no percentage reportedSilencing raised AT8- and MC1-reactive tau by ~50 to 90% in PS19 neurons challenged with tau fibrils; in wild-type neurons it cut synaptophysin puncta ~40%, PSD95 puncta ~30% and neurofilament light chain ~40%, and reduced viability[1]
CCL3Mouse spinal cord (in vivo)AUMsilence sdASO, three intrathecal injections, 10 mg/kg~60% (mRNA at day 7)Fewer CD11b+ macrophages and microglia at the lesion (p = 0.01); significantly more treated mice performed plantar placement on days 5-7 (p < 0.05, Fig. 4B); no significant change in BMS score, and none in lesion volume in the pretreated cohort[3]
NR4A2U87-MG, 15037, 14015s (patient-derived)AUMsilence sdASO, 10 μM, 42 hoursReduced expression in all three lines (Western blot)Decreased proliferation and invasion (Boyden chamber); apoptosis by Annexin V, with caspase 8 cleavage in two of the three lines[2]
miR-134-5pHippocampal slices (rat, mouse)AUMantagomir sdASO, 1 μM bath, 3 hours~80% (qRT-PCR)Rescued LTP and STC deficits in Aβ model, upregulated CREB-1 and BDNF[4]
MSUT2Primary mouse neurons (CD1 cortex and hippocampus)AUMsilence sdASO, six sequences, 1 μMProtein suppressed by all six sequences; no percentage reportedReduced tau spreading between neurons via adenosinergic signaling (ASAP1 pathway); tau inclusions and insoluble tau fell while alpha-synuclein aggregates did not[5]
TRIB2LNCaP-ENR prostate cancer xenografts, nude mice, n = 3 (in vivo)AUMsilence sdASO, intratumoral, 2 mg/kg/day every fourth day for 4 weeksNo knockdown figure reportedDecreased growth of enzalutamide-resistant prostate tumors; the study's neuroendocrine and BRN2 results come from its overexpression and shRNA arms[6]

5. In vivo efficacy in models of neurological disease

The performance of a research tool in vivo is critical for assessing its potential for translational applications. The in vivo work reviewed below is of two kinds, and the sections that follow keep them apart: AUMsilence sdASO against CCL3 in a mouse model of spinal cord injury, where three doses were needed for a result at day 7; and AAV-delivered TRIM11 in two mouse models of tauopathy, which is gene delivery by a viral vector rather than an oligonucleotide, and whose figures belong to it and not to the platform.

5.1 Alzheimer's disease and tauopathies

In a study published in Science, the part played by TRIM11 (validated using AUMsilence sdASO) was examined through AAV-mediated gene delivery to the brains of mouse models of Alzheimer's disease and tauopathy1. The study employed two complementary mouse models: PS19 mice (expressing human tau P301S mutation) and 3×Tg-AD mice (expressing tau P301L, APP K595N/M596L, and PS1 M146V mutations). AAV9 vectors encoding TRIM11 or GFP control were delivered via stereotaxic intrahippocampal injection (for targeted delivery) or intracerebroventricular injection (for broader CNS distribution). The AAV9 serotype was selected for its efficient transduction of neurons and glia in the CNS.

In PS19 mice, AAV9-TRIM11 was delivered to the hippocampus at 2.5 months of age and the brains and behavior were analyzed at approximately 10 months, where the hippocampi of treated mice contained approximately 55% less tau pathology, quantified by AT8 immunostaining (recognizing phosphorylated tau at Ser202/Thr205). In the 3×Tg-AD model, where delivery was at 12 months of age, when those mice already carried a substantial amount of tau pathology in that region, AAV9-TRIM11 gave approximately 30% reduction in NFT-like inclusions by immunohistochemistry and an approximately 80 to 90% reduction in p-tau species reactive to AT8 and PHF-1 by Western blot. The evidence that TRIM11 cleared tau aggregates already present is a comparison of AT8 staining in treated brains at 13 months against uninjected brains at 12 months, which the authors read as suggesting that TRIM11 cleared tau aggregates already present.

Neuroinflammation fell in both models, by different amounts, and the figures belong to the model they were measured in. In PS19 mice, hippocampal GFAP immunoreactivity fell by approximately 50% and microgliosis by approximately 40%; in 3×Tg-AD mice, GFAP and Iba1 immunoreactivity fell by approximately 30% and 60% respectively. No cytokine measurement of any kind is reported. In PS19 mice the treated hippocampi also showed an approximately 50% increase in MAP2 immunoreactivity, an approximately 70% increase in neurofilament light chain immunoreactivity and an approximately 40% increase in NeuN expression, which the authors read as protection of dendrites, axons and neurons rather than as cell counts. Behaviorally, PS19 mice preferred the novel object in an object recognition test and hung longer in the wire hang test; Y-maze spontaneous alternation was measured in the fibril-accelerated PS19 arm and in 3×Tg-AD mice, and improved in both. The controls were an AAV9-GFP vector and age-matched wild-type animals. The mechanism of TRIM11's protective effect involves three complementary activities: promoting proteasomal degradation of tau through SUMOylation, acting as a molecular chaperone to prevent tau aggregation, and functioning as a disaggregase to dissolve pre-existing tau fibrils in an ATP-independent manner.

Reduced tau pathology

~55% reduction in NFT-like tau inclusions in PS19 mice and ~30% in 3×Tg-AD mice, by immunohistochemistry, with an ~80 to 90% reduction in p-tau species reactive to AT8 and PHF-1 in the 3×Tg-AD arm, by Western blot1.

Cleared pre-existing aggregates

Delivered at 12 months of age, after a substantial amount of tau pathology had already formed, AAV9-TRIM11 left AT8 staining at 13 months lower than in uninjected brains at 12 months1. That comparison is what the study offers as evidence that TRIM11 cleared aggregates already present.

Suppressed neuroinflammation

In PS19 mice, hippocampal astrogliosis (GFAP) fell by ~50% and microgliosis (Iba1) by ~40%; in 3×Tg-AD mice the same two markers fell by ~30% and ~60%1. The vector was delivered into the hippocampus and the quantification is hippocampal. No cytokine measurement is reported.

Improved cognitive and motor function

PS19 mice preferred the novel object in an object recognition test and hung longer in the wire hang test; Y-maze spontaneous alternation improved in the fibril-accelerated PS19 arm and in 3×Tg-AD mice1. PS19 mice were injected at 2.5 months and assessed once at approximately 10 months, so this is one endpoint under continuously expressed vector rather than a measurement of how long an effect lasts after treatment stops.

5.2 Spinal cord injury

The CCL3 study also recorded where the oligonucleotide reached in the injured spinal cord3. Seven days after intrathecal injection, fluorescently labeled oligonucleotide was present at the lesion site. Flow cytometry detected it in CD11b+/CD45low microglia and in CD11b+/CD45high monocyte-derived macrophages, and histology detected it in CD11b+ macrophages and microglia and in GFAP+ astrocytes. No uptake was detected in NeuN+ neurons, which the authors suggest could be explained by those cells lying at some distance from the lesion epicenter. Five days after injury, treated animals carried significantly fewer CD11b+ macrophages and microglia beside the lesion, at p = 0.01; astrocyte numbers and SMI-32+ indicators of axonal damage were no different between groups, at p = 0.94 and p = 0.72, and neutrophil numbers measured by flow cytometry at day 1 were no different either, at p = 0.43.
Two of the outcomes this study measured were negative, and they are given here as the study gives them. Locomotor scores on the Basso Mouse Scale did not improve significantly over controls, in the cohort dosed from immediately after injury, twelve animals per group, or in the cohort pretreated 24 hours beforehand, ten per group. What reached significance was plantar placement: a significantly higher percentage of treated mice achieved it on days 5-7 after injury in the first cohort and on days 3-7 in the pretreated cohort, and the authors head that result as a mild functional improvement. In the pretreated cohort, which is the only one these two were measured in, quantitative analysis of lesion volume at day 28, nine animals per group, showed no significant reduction in lesion size, and no difference in myelin content was detected between groups. The authors suggest the limited effect could be explained by the degree of suppression reached, approximately 60%, and their own conclusion is that targeting CCL3 this way reduced the proinflammatory response and produced a mild but significant functional improvement after spinal cord injury.

5.3 Glioblastoma

While no paper reviewed here reports in vivo data using AUMsilence sdASO in glioblastoma, the NR4A2 study, which investigates NR4A2 as a drug target, showed an in vivo effect using a small molecule antagonist (DIM-C-pPhCl) that phenocopies the ASO knockdown effects2. Female athymic nu/nu mice bearing subcutaneous U87-MG xenografts, five animals per group, were treated with 30 mg/kg/day DIM-C-pPhCl via intraperitoneal injection for three weeks. This treatment resulted in significant reduction in tumor weight compared to vehicle control. Molecular analysis of tumor tissue revealed upregulation of cleaved caspase-8, and the study is explicit that cleaved caspase-7 and cleaved PARP were not upregulated in those tumors, so the apoptotic signature in vivo is narrower than the one the oligonucleotide produced in culture. The in vitro effects of NR4A2-targeting AUMsilence sdASO on glioblastoma cell proliferation, invasion and apoptosis suggest a case for future in vivo studies using direct ASO administration. In the spinal cord injury study the oligonucleotide reached the lesion after an intrathecal dose, which is the only CNS delivery any paper here reports.

6. Key research applications in neuroscience

Peer-reviewed publications report the use of AUMsilence sdASO across a spectrum of neuroscience research areas. These studies used the oligonucleotides in cultured cells, in acute slices and in animals.

Neurodegenerative disease

Elucidating disease mechanisms and validating candidate targets in models of Alzheimer's, Parkinson's, and other tauopathies. The technology enables loss-of-function studies in primary neurons and disease-relevant cell models, complementing gain-of-function approaches using viral vectors or transgenic models.

Example: TRIM11 knockdown in PS19 neurons exacerbated tau aggregation, validating its protective role1. MSUT2 knockdown reduced tau spreading via adenosinergic signaling5.

Brain tumors

Investigating genes that drive glioblastoma progression and exploring silencing strategies. The patient-derived glioblastoma lines resist conventional transfection, and here the oligonucleotide was added to the well.
Example: NR4A2 knockdown in U87-MG and in two patient-derived glioblastoma cell lines reduced proliferation and invasion and induced apoptosis2.

CNS injury and repair

Investigating how far reducing neuroinflammation changes the course of recovery after spinal cord injury or traumatic brain injury. Intrathecal injection carries the oligonucleotide to the lesion site without a transfection reagent or a viral vector.

Example: three intrathecal injections of CCL3-targeting AUMsilence sdASO reduced CCL3 in the injured mouse spinal cord by approximately 60% at day 7 and lowered the number of macrophages and microglia at the lesion; locomotor scores did not change significantly, and neither did lesion volume in the pretreated cohort, while significantly more treated mice performed plantar placement on days 5-73.

Synaptic plasticity

Investigating microRNA and protein-coding gene roles in long-term potentiation, memory formation, and synaptic tagging. Bath application to slice preparations enables rapid functional studies without the delays associated with viral transduction.

Example: miR-134-5p antagomir rescued LTP and synaptic tagging deficits in Aβ-treated hippocampal slices within hours, upregulating CREB and BDNF4.

Neurodevelopment

Studying the function of key genes in neuronal differentiation, migration, and synapse formation. The technology is compatible with primary neuronal cultures and organoid systems where transfection is challenging.

Example: LINE-1 inhibition with AUMsilence sdASO reduced transdifferentiation efficiency of MEFs into dopaminergic neurons, revealing role of retrotransposition in cellular plasticity7.

Neuropsychiatric disorders

Exploring the genetic underpinnings of complex traits like schizophrenia and cognitive function. The technology enables functional validation of genes identified through genome-wide association studies.

Example: in a placental genomics study, AUMsilence sdASO cut EPS15 expression by 50% in a human placenta-derived cell line and raised the two genes the study had predicted it regulated, SPATA13 by 795% and FAM214A by 377%, validating one predicted regulatory link; the study's associations with cognition and schizophrenia come from its transcriptome-wide association analysis rather than from the oligonucleotide8.

7. Conclusion

AUM BioTech's self-delivering antisense oligonucleotide platform has been used across cultured neurons, acute slices and animal models of neurological disease. By overcoming the delivery barriers that limit conventional gene silencing approaches in the CNS, AUMsilence sdASO enables scientists to conduct functional genomics studies in clinically relevant primary cell and in vivo models. The gymnotic uptake mechanism eliminates the need for transfection reagents, viral vectors, or complex formulations, simplifying experimental workflows and reducing confounding variables associated with delivery vehicles.

The published work spans models of Alzheimer's disease, spinal cord injury, glioblastoma, and synaptic plasticity, and it includes the rescue of long-term potentiation and of synaptic tagging and capture within hours of bath application to acute hippocampal slices.

The chemical modifications that enable self-delivery also confer favorable pharmacokinetic properties, including nuclease resistance and sustained duration of action, making AUMsilence sdASO particularly well-suited for in vivo neuroscience research where repeated dosing may be impractical. A loss-of-function experiment of this kind is how a candidate gene identified by genomic or proteomic work is tested in a neuronal model.

8. References

  1. 01Zhang et al. TRIM11 protects against tauopathies and is down-regulated in Alzheimer's disease. Science 2023;381(6656):eadd6696.
  2. 02Karki et al. Nuclear receptor 4A2 (NR4A2) is a druggable target for glioblastomas. Journal of Neuro-Oncology 2020;146(1):25-39.
  3. 03Pelisch et al. Use of a Self-Delivering Anti-CCL3 FANA Oligonucleotide as an Innovative Approach to Target Inflammation after Spinal Cord Injury. eNeuro 2021;8(2):ENEURO.0338-20.2021.
  4. 04Baby et al. MicroRNA-134-5p inhibition rescues long-term plasticity and synaptic tagging/capture in an Aβ(1-42)-induced model of Alzheimer's disease. Aging Cell 2020;19(1):e13046.
  5. 05Xu et al. MSUT2 regulates tau spreading via adenosinergic signaling mediated ASAP1 pathway in neurons. Acta Neuropathologica 2024;147(1):55.
  6. 06Monga et al. Tribbles 2 pseudokinase confers enzalutamide resistance in prostate cancer by promoting lineage plasticity. Journal of Biological Chemistry 2022;298(2):101556.
  7. 07Della Valle et al. Transdifferentiation of mouse embryonic fibroblasts into dopaminergic neurons reactivates LINE-1 repetitive elements. Stem Cell Reports 2020;14(1):60-74.
  8. 08Bhattacharya et al. Placental genomics mediates genetic associations with complex health traits and disease. Nature Communications 2022;13:706.

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