Late Gene Expression–Deficient Cytomegalovirus Vectors Elicit Conventional T Cells That Do Not Protect Against SIV
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Cytomegalovirus (CMV)–based vaccines aim to exploit unique immunological adaptations, including host manipulation and immune evasion strategies. Translating CMV-based vaccines from rhesus macaques to humans requires translating the immune factors responsible for efficacy, as well as vaccine vectors that are sufficiently safe for widespread use. Researchers examined the impact of a stringent attenuation strategy on vector-induced immune protection against simian immunodeficiency virus (SIV) in rhesus macaques of both sexes.
Spike and Nsp6 Are Key Determinants of SARS-CoV-2 Omicron BA.1 Attenuation
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The ability of the SARS-CoV-2 virus to mutate and create variants of concern demands new vaccines to control the COVID-19 pandemic. The SARS-CoV-2 Omicron variant was shown to be more immune evasive and less virulent than current major variants. The spike (S) protein in this variant carries many mutations that drive these phenotypes. Researchers generated a chimeric recombinant SARS-CoV-2 virus encoding the S gene of Omicron (BA.1 lineage) in an ancestral SARS-CoV-2 isolate and compared it with the naturally circulating Omicron variant.
PIKFYVE Inhibition Mitigates Disease in Models of Diverse Forms of ALS
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Investigators showed that pharmacological suppression of PIKFYVE activity reduces pathology and extends survival of animal models and patient-derived motor neurons representing diverse forms of amyotrophic lateral sclerosis (ALS). Upon PIKFYVE inhibition, exocytosis is activated to transport aggregation-prone proteins out of the cells, a process that does not require stimulating macroautophagy or the ubiquitin-proteosome system. These findings suggest therapeutic potential to manage multiple forms of ALS. Supported by ORIP (S10OD021553) and NINDS.
Production and Characterization of Monoclonal Antibodies to Xenopus Proteins
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Monoclonal antibodies are powerful and versatile tools that enable the study of proteins in diverse contexts. They are often utilized to assist with identification of subcellular localization and characterization of the function of target proteins of interest. However, because there can be considerable sequence diversity between orthologous proteins in Xenopus and mammals, antibodies produced against mouse or human proteins often do not recognize Xenopus counterparts.
Multimodal Single-Cell and Whole-Genome Sequencing of Small, Frozen Clinical Specimens
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Single-cell RNA sequencing has led to improved understanding of tumor heterogeneity to drug response, but the broad application of those methods remains challenging due to practical requirements that are incompatible with clinical care workflow, such as the need for large and fresh tissues. The researchers demonstrated that several single-cell genomics techniques are feasible from small, frozen tissues and provide biological data outputs similar to those collected from fresh tissue while reducing artifactual signals and compositional biases introduced by fresh-tissue processing.
Chronic TREM2 Activation Exacerbates Aβ-Associated Tau Seeding and Spreading
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Using a mouse model for amyloidosis in which Alzheimer’s Disease (AD)–associated tau is injected into the brain to induce amyloid β (Aβ)–dependent tau seeding/spreading, investigators found that chronic administration of an activating triggering receptor expressed on myeloid cells 2 (TREM2) antibody increases microglial activation of dystrophic neurites surrounding Aβ plaques (NP) but increases NP-tau pathology and neuritic dystrophy without altering Aβ plaque burden.
A Deep Learning Platform to Assess Drug Proarrhythmia Risk
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Investigators trained a convolutional neural network (CNN) classifier to learn and ultimately identify features of in vitro action potential recordings of human induced pluripotent stem cell (iPSC)–derived cardiomyocytes (hiPSC-CMs) that are associated with lethal Torsade de Pointes arrhythmia. The CNN classifier accurately predicted the risk of drug-induced arrhythmia. The risk profiles of the test drugs were similar across hiPSC-CMs derived from different healthy donors.
3D-Bioprinted Phantom With Human Skin Phototypes for Biomedical Optics
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Human skin offers important physical and immunological protection based on its makeup with diverse cell types, including melanocytes, and variations in skin phototypes controlled by melanin concentration have negatively affected many optic technologies and wearable health-tracking electronic devices. To mimic the effects of melanosome variation, investigators studied optical properties and photoacoustic signal of synthetic melanin to create a 3D bioprinting rendition of the human epidermal thin layers.
Elevated Transferrin Receptor Impairs T Cell Metabolism and Function in Systemic Lupus Erythematosus
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Systemic lupus erythematosus (SLE) is an autoimmune disease in which dysfunctional T cells exhibit abnormalities in metabolism. Investigators performed a CRISPR screen to examine mechanisms associated with the role of excess iron in dysfunctional T cells. The transferrin receptor (CD71) was identified as differentially critical for Type 1 T helper cells and inhibitory for induced regulatory T cells. Activated T cells induced CD71 and iron uptake, which was exaggerated in SLE-prone T cells.
The Ras GTPase‐Activating‐Like Protein IQGAP1 Bridges Gasdermin D to the ESCRT System to Promote IL‐1β Release via Exosomes
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The investigators identified IQGAP1, a scaffold protein, as a gasdermin D (GSDMD)–interacting protein through a nonbiased proteomic analysis. Functional investigation indicated that the interaction is required for lipopolysaccharide (LPS)- and ATP-induced exosome release. Further analysis revealed that IQGAP1 serves as an adaptor that bridges GSDMD and the associated IL‐1β complex to Tsg101 and enables the packaging of GSDMD and IL‐1β into exosomes. This process is dependent on an LPS‐induced increase in GTP‐bound CDC42, a small GTPase known to activate IQGAP1.