Opposing role of phagocytic receptors MERTK and AXL in Progranulin deficient FTD
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1053290 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Genetic mutations in the progranulin gene, GRN, cause frontotemporal dementia and a lysosomal storage disorder. Using single-nuclei RNA sequencing of the post-mortem brain tissue from heterozygous pathogenic granulin variant (GRN+/-) carriers we found dysregulation of microglia, phagocytosis and the phagocytic receptors MERTK and AXL. Exogenous progranulin regulated MERTK and AXL RNA expression in human microglia induced from iPSCs irrespective of GRN mutation status, without directly binding to MERTK or AXL proteins. We generated double knock-out mice and found that constitutive homozygous loss of Grn and Mertk (Grn-/-;Mertk-/-) rescued microglial disease signature while constitutive homozygous loss of Grn and Axl (Grn-/-;Axl-/-) worsened the microglial disease signature. Higher levels of AXL protein, but not MERTK protein, in the post-mortem superior temporal gyrus correlated with worse cross-sectional functional impairment (CDR sum of boxes) by both GRN+/- mutation carriers and non-carrier controls. These data explain in part the inflammation seen in GRN-FTD and are applicable to other inflammatory states in which PGRN, MERTK and AXL play regulatory roles, including cancer, sepsis, stroke, diabetes and obesity. The interaction between GRN, MERTK and AXL opens potential new therapeutic avenues to intervene on this inflammatory axis.
2025-06-30 | GSE250280 | GEO
Project description:We aimed to investigate the strategies to protect against pancreatitis severity and we focused on AXL and MERTK tyrosine kinases receptors, which are the negative regulator of the innate immune response. In order to investigate the underlying mechanism of AXL and MERTK in mediating pancreatic necrosis, we performed high-throughput mRNA sequencing on the pancreatic tissues of 6 C57BL/6J wild type mice and 6 Axl-/-Mertk-/- mice under hyperstimulation of caerulein.
2024-12-15 | GSE191008 | GEO
Project description:Many apoptotic thymocytes are generated during the course of T cell selection in the thymus, yet the machinery through which these dead cells are recognized and phagocytically cleared is incompletely understood. We find that the TAM receptor tyrosine kinases Axl and Mer, which are co-expressed by a specialized set of phagocytic thymic macrophages, are essential components of this machinery. Axl-/-Mertk-/- double mutant mice exhibited a marked accumulation of apoptotic cells during the time that autoreactive and nonreactive thymocytes die. Unexpectedly, the double mutants also displayed a profound deficit in the total number of phagocytic macrophages in the thymus, and concomitantly exhibited diminished expression of key non-TAM engulfment systems in the macrophages that remain. These previously unrecognized deficits were not confined to the thymus, and were also evident in the bone marrow and spleen. They had pleiotropic metabolic consequences for the double mutants, which included severe dysregulation of hemoglobin turnover, iron metabolism, and erythropoiesis.
2022-07-12 | GSE192363 | GEO
Project description:Multiple FTD patient-specific iPSC lines were generated for the first time, Human neurons of progranulin haploinsufficiency have been established. PGRN S116X neurons are more sensitive to kinase inhibitors-induced cell stress, which can be rescued by ectopic progranulin expression, revealing progranulin-dependent cellular defects in FTD. Microarray analysis reveals that the serine/threonine kinase S6K2 (RPS6KB2) and other genes involved in MAPK signaling are dysregulated specifically in neurons with progranulin deficiency. 32 independent human neuronal cultures were analyzed in this study
2012-10-25 | E-GEOD-40378 | biostudies-arrayexpress
Project description:Multiple FTD patient-specific iPSC lines were generated for the first time, Human neurons of progranulin haploinsufficiency have been established. PGRN S116X neurons are more sensitive to kinase inhibitors-induced cell stress, which can be rescued by ectopic progranulin expression, revealing progranulin-dependent cellular defects in FTD. Microarray analysis reveals that the serine/threonine kinase S6K2 (RPS6KB2) and other genes involved in MAPK signaling are dysregulated specifically in neurons with progranulin deficiency.
2012-10-25 | GSE40378 | GEO
Project description:Patients with frontotemporal dementia (FTD) resulting from granulin (GRN) haploinsufficiency have reduced levels of progranulin and exhibit dysregulation in inflammatory and lysosomal networks. Microglia produce high levels of progranulin, and reduction of progranulin in microglia alone is sufficient to recapitulate inflammation, lysosomal dysfunction, and hyperproliferation in a cell-autonomous manner. Therefore, targeting microglial dysfunction caused by progranulin insufficiency represents a potential therapeutic strategy to manage neurodegeneration in FTD. Limitations of current progranulin-enhancing strategies necessitate the discovery of new targets.To identify compounds that can reverse microglial defects in Grn-deficient mouse microglia, we performed a compound screen coupled with high throughput sequencing to assess key transcriptional changes in inflammatory and lysosomal pathways. Positive hits from this initial screen were then further narrowed down based on their ability to rescue cathepsin activity, a critical biochemical readout of lysosomal capacity. The screen identified nor-binaltorphimine dihydrochloride (nor-BNI) and dibutyryl-cAMP, sodium salt (DB-cAMP) as two phenotypic modulators of progranulin deficiency. In addition, nor-BNI and DB-cAMP also rescued cell cycle abnormalities in progranulin-deficient cells. These data highlight the potential of a transcription-based platform for drug screening, and advance two novel lead compounds for FTD.
2020-08-02 | GSE143144 | GEO
Project description:Heterozygous GRN (progranulin) mutations cause frontotemporal dementia (FTD) due to haploinsufficiency, and increasing progranulin levels is a major therapeutic goal. Several microRNAs, including miR-29b, negatively regulate progranulin protein levels. Antisense oligonucleotides (ASOs) are emerging as a promising therapeutic modality for neurological diseases, but strategies for increasing target protein levels are limited. Here, we tested the efficacy of ASOs as enhancers of progranulin expression by sterically blocking the miR-29b binding site in the 3' UTR of the human GRN mRNA. We found 16 ASOs that increase progranulin protein in a dose-dependent manner in neuroglioma cells. A subset of these ASOs also increased progranulin protein in iPSC-derived neurons and in a humanized GRN mouse model. In FRET-based assays, the ASOs effectively competed miR-29b from binding to the GRN 3' UTR RNA. The ASOs increased levels of newly synthesized progranulin protein by increasing its translation, as revealed by polysome profiling. Together, our results demonstrate that ASOs can be used to effectively increase target protein levels by partially blocking miR binding sites. This ASO strategy may be therapeutically feasible for progranulin-deficient FTD as well as other conditions of haploinsufficiency.
2022-08-01 | GSE188498 | GEO
Project description:Microglia repair injury and maintain homeostasis in the brain, but whether aberrant microglial activation can contribute to neurodegeneration remains unclear. Here, we use transcriptome profiling to demonstrate that deficiency in frontotemporal dementia (FTD) gene progranulin (Grn) leads to an age-dependent, progressive up-regulation of lysosomal and innate immunity genes, increased complement production, and synaptic pruning activity in microglia. During aging, Grn-/- mice show profound accumulation of microglia and preferential elimination of inhibitory synapses in the ventral thalamus, which contribute to hyperexcitability in the thalamocortical circuits and obsessive-compulsive disorder (OCD)-like grooming behaviors. Remarkably, blocking complement activation by deleting C1qa gene significantly reduces synaptic pruning by Grn-/- microglia, and mitigates neurodegeneration, behavioral phenotypes and premature mortality in Grn-/- mice. These results uncover a previously unrecognized role of progranulin in suppressing microglia activation during aging, and support the idea that blocking complement activation is a promising therapeutic target for neurodegeneration caused by progranulin deficiency. Gene expression study in multiple brain regions from a mouse model of progranulin deficiency Please note that 9 outlier samples were excluded from data analysis. Therefore, there are 326 raw data columns (i.e. 163 samples) in the non_normalized data matrix while 154 samples are represented here.
2016-03-31 | E-GEOD-75083 | biostudies-arrayexpress
Project description:Tolerogenic dendritic cells (tol-DCs) offer a promising therapeutic potential for autoimmune diseases. Tol-DCs have been reported to inhibit immunogenic responses, yet little is known about the mechanisms controlling their tolerogenic status, as well as associated specific markers. Here we show that the anti-inflammatory TAM receptor tyrosine kinase MERTK, is highly expressed on clinical grade dexamethasone-induced human tol-DCs and mediates their tolerogenic effect. Neutralization of MERTK in allogenic mixed lymphocyte reactions as well as autologous DC-T cell cultures leads to increased T cell proliferation and IFN-g production. Additionally, we identify a previously unrecognized non-cell autonomous regulatory function of MERTK expressed on DCs. Recombinant Mer-Fc protein, used to mimic MERTK on DCs, suppresses naïve and antigen-specific memory T cell activation. This mechanism is mediated by the neutralization of the MERTK agonist Protein S (PROS1) expressed by T cells. We find that MERTK and PROS1 are expressed in human T cells upon TCR activation and drive an autocrine pro-proliferative mechanism. Collectively, these results suggest that MERTK on tol-DCs directly inhibits T cell activation through the competition for PROS1 interaction with MERTK in the T cells. Targeting MERTK may provide an interesting approach to effectively increase or suppress tolerance for the purpose of immunotherapy. The complete database comprised the expression measurements of 54,675 genes for: immature (n=9), mature (n=7) and tolerogenic (n=8). Influence of treatment with dexamethasone (n=3) and LPS (n=2) are included.
2015-01-29 | E-GEOD-56017 | biostudies-arrayexpress
Project description:Regeneration of alveolar bone is an essential step in restoring healthy function following tooth extraction. Growth of new bone in the healing extraction socket can be variable and often unpredictable when systemic comorbidities are present, leading to the need for additional therapeutic targets to accelerate the regenerative process. This study examined the effect of signaling through the TAM (Tyro3, Axl, Mertk) family of receptors on alveolar bone regeneration. We performed RNA sequencing on human alveolar bone stem cells treated with a pan-TAM inhibitor in vitro. We also performed RNA sequencing on tissue isolated from the extraction socket of WT and Mertk-\- mice.
2023-10-12 | GSE223778 | GEO