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Schüle, B.

Publications and source records attributed to Schüle, B..

3 recordsLinked to original sources

APOE4 Drives Uniquely Dysfunctional Human Microglial States in Alzheimer's Disease

Variation in APOE, notably the {varepsilon}4 allele, profoundly shapes risk and severity of late-onset Alzheimers disease (AD), yet how it remodels human microglial states remains unresolved. We combine spatially resolved proteomic profiling with single-nuclear multiomic analyses to define microglial organization across APOE3/3 and APOE4/4 genotypes in AD. Quantifying condition-associated variation across the cellular manifold reveals a continuous landscape of microglial states. APOE4/4 shifts cells toward terminal states marked by loss of homeostatic identity, metabolic disruption, and incomplete acquisition of disease-associated programs. We identify an APOE4/4-enriched population in AD that exhibits inflammatory signaling without effective metabolic or phagocytic engagement, localizing to niches of gliosis and senescence, and coupled to chronic stress adaptation programs. Together with evidence that APOE4/4 potentiates the activation threshold of nascent microglia, these findings establish a unified framework for human microglial state change, linking genetic risk to spatial and molecular organization of immune responses in the AD brain. Graphical Abstract.APOE4/4 in Alzheimers disease reshapes microglial fate along continuous trajectories characterized by proteomic, transcriptional, and epigenetic programs consistent with chronic stress adaptation, alongside distinct composite spatial niches comprised of astrocytic gliosis and cellular senescence. O_FIG O_LINKSMALLFIG WIDTH=168 HEIGHT=200 SRC="FIGDIR/small/733295v1_ufig1.gif" ALT="Figure 1"> View larger version (75K): org.highwire.dtl.DTLVardef@b2afa4org.highwire.dtl.DTLVardef@12978f8org.highwire.dtl.DTLVardef@1c4e46dorg.highwire.dtl.DTLVardef@170e44d_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Robust nuclease-dead S. aureus dCas9-mediated alpha-synuclein knockdown in substantia nigra in a humanized mouse model of Parkinson's disease

Parkinsons disease (PD) is becoming increasingly prevalent due to an aging society, which places a substantial disease burden on patients and their families and an annual cost estimated at 52 billion dollars. However, no approved disease modulatory therapies that halt disease progression are available. Alpha-synuclein is a critical therapeutic target found in aggregated form in Lewy bodies which is the diagnostic hallmark of PD. Familial autosomal dominant forms of PD can present with causative exonic point mutations, copy number multiplications, and non-coding risk variants in the alpha-synuclein gene. The disease onset, severity, and progression depend on the gene expression levels of the alpha-synuclein. Here, we demonstrate that Streptococcus aureus dCas9 (sadCas9)-mediated CRISPR interference (CRISPRi) reduces alpha-synuclein mRNA and protein levels in a humanized mouse model. The mechanism of action is based on the principle that a complementary single guide RNA (sgRNA) recruits the sadCas9 protein to the promoter region of alpha-synuclein and modulates target gene transcription, leading to reduced gene expression. We show robust downregulation of alpha-synuclein in neurons after unilateral stereotactic injection into the substantia nigra of adult mice 1 and 6 months after surgery. This work shows proof of concept that viral-mediated sadCas9 CRISPR interference can be a promising therapeutic strategy to reduce alpha-synuclein in vivo. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=168 SRC="FIGDIR/small/556425v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@4d9247org.highwire.dtl.DTLVardef@beb419org.highwire.dtl.DTLVardef@21e0f9org.highwire.dtl.DTLVardef@391d5a_HPS_FORMAT_FIGEXP M_FIG C_FIG eTOC synopsisThis study focuses on the development of an AAV9 nuclease-dead S. aureus CRISPR/Cas9 expression system designed to target the human SNCA promoter. The objective is to achieve downregulation of -synuclein (a-syn) expression. After performing surgery and introducing the expression system, the levels of a-syn were measured at 1 month and 6 months post-surgery. The results indicate a significant downregulation of a-syn at both time points. Furthermore, it was observed that the initial immune response to the system attenuated over time, reaching control levels at the 6-month mark. These findings suggest the potential of this expression system for long-term downregulation of a-syn and provide insights into the immune response dynamics associated with its use.

neuroscience↗

Identification and Validation of N-Acetylputrescine in Combination With Non-Canonical Clinical Features As a Parkinsons Disease Biomarker Panel

Parkinsons disease is a progressive neurodegenerative disorder in which loss of dopaminergic neurons in the substantia nigra results in a clinically heterogeneous group with variable motor and non-motor symptoms with a degree of misdiagnosis. Only 3-5% of sporadic Parkinsons patients present with genetic abnormalities, thus environmental, metabolic, and other unknown causes contribute to the pathogenesis of Parkinsons disease, which highlights the critical need for biomarkers. There could be a significant clinical benefit to treating Parkinsons disease at the earliest stage and identify at-risk populations once disease-modifying treatments are available. In the present study, we prospectively collected and analyzed plasma samples from 201 Parkinsons disease patients and 199 age-matched non-diseased controls. Multiomic and Bayesian artificial intelligence analysis of molecular and clinical data identified the diagnostic utility of N-acetyl putrescine (NAP) in combination with smell (B-SIT), depression/anxiety (HADS), and acting out dreams (RBD1Q) clinical measurements. The clinical and biomarker panel demonstrated an area under the curve, AUC = 0.9, positive predictive value, PPV = 0.91, and negative predictive value, NPV = 0.66 utilizing all four variables. The assessed diagnostic panel demonstrates combinatorial utility in diagnosing Parkinsons disease, allowing for an integrated interpretation of disease pathophysiology and highlighting the use of multi-tiered panels in neurological disease diagnosis.

neuroscience↗