Project description:The immune and nervous systems are highly interactive, however, little is known about how immune cells and their derived molecules impact brain function. Here we show that T cells play a critical role in retrieval of contextual fear conditioning (CFC) memory. Single-nuclei sequencing (snRNAseq) of engram neurons and non-engram neurons from the dentate gyrus one day after CFC learning revealed new evidence about differential expression of immune-related and synaptic plasticity-related genes, in SCID vs. wild-type mice. These findings present a comprehensive picture on how T cells and their derived cytokines could regulate memory retrieval and provide new insights into the nature of neuroimmune interactions at the transcriptional level in neurons. Overall, restoration of T cells or IL-4R signaling might lead to selective rescue of memory retrieval, and proffer a valuable strategy for treating memory loss.
Project description:The immune and nervous systems are highly interactive, however, little is known about how immune cells and their derived molecules impact brain function. Here we show that T cells play a critical role in retrieval of contextual fear conditioning (CFC) memory. Single-nuclei sequencing (snRNAseq) of engram neurons and non-engram neurons from the dentate gyrus one day after CFC learning revealed new evidence about differential expression of immune-related and synaptic plasticity-related genes, in SCID vs. wild-type mice. These findings present a comprehensive picture on how T cells and their derived cytokines could regulate memory retrieval and provide new insights into the nature of neuroimmune interactions at the transcriptional level in neurons. Overall, restoration of T cells or IL-4R signaling might lead to selective rescue of memory retrieval, and proffer a valuable strategy for treating memory loss.
Project description:The immune and nervous systems are highly interactive, however, little is known about how immune cells and their derived molecules impact brain function. Here we show that T cells play a critical role in retrieval of contextual fear conditioning (CFC) memory. Single-nuclei sequencing (snRNAseq) of engram neurons and non-engram neurons from the dentate gyrus one day after CFC learning revealed new evidence about differential expression of immune-related and synaptic plasticity-related genes, in SCID vs. wild-type mice. These findings present a comprehensive picture on how T cells and their derived cytokines could regulate memory retrieval and provide new insights into the nature of neuroimmune interactions at the transcriptional level in neurons. Overall, restoration of T cells or IL-4R signaling might lead to selective rescue of memory retrieval, and proffer a valuable strategy for treating memory loss.
Project description:Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to lack of appropriate human models. Here, we engineered new human induced pluripotent stem cell (hiPSC)-derived neuronal lines to express 4R Tau and 4R Tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes including shared transcriptomic signatures, autophagic body accumulation, and reduced neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of seeding-induced Tau propagation, including retromer VPS29 and genes in the UFMylation cascade. In progressive supranuclear palsy (PSP) and Alzheimer’s Disease (AD) brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade in vitro and in vivo suppressed seeding-induced Tau propagation. This model provides a robust platform to identify novel therapeutic strategies for 4R tauopathy.
Project description:Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to lack of appropriate human models. Here, we engineered new human induced pluripotent stem cell (hiPSC)-derived neuronal lines to express 4R Tau and 4R Tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes including shared transcriptomic signatures, autophagic body accumulation, and reduced neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of seeding-induced Tau propagation, including retromer VPS29 and genes in the UFMylation cascade. In progressive supranuclear palsy (PSP) and Alzheimer’s Disease (AD) brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade in vitro and in vivo suppressed seeding-induced Tau propagation. This model provides a robust platform to identify novel therapeutic strategies for 4R tauopathy.
Project description:Tau is a microtubule-binding protein expressed in neurons and the equal ratio between 4-repeat (4R) and 3-repeat (3R) isoforms are maintained in normal adult brain function. Dysregulation of 3R:4R ratio causes tauopathy and human neurons that recapitulate tau isoforms in health and disease will provide a platform for elucidating pathogenic processes involving tau pathology. We carried out extensive characterizations of tau isoforms expressed in human neurons derived by microRNA-induced neuronal reprogramming of adult fibroblasts. Transcript and protein analyses showed miR-neurons expressed all six isoforms with the 3R:4R isoform ratio equivalent to that detected in human adult brains. Also, miR-neurons derived from familial tauopathypatients with a 3R:4R ratio altering mutation showed increased 4R tau and the formation of insoluble tau with seeding activity. Our results collectively demonstrate the utility of miRNA-induced neuronal reprogramming to recapitulate endogenous tau regulation comparable to the adult brain in health and disease.