Restoring metabolism of myeloid cells reverses cognitive decline in ageing.
Ageing is characterized by the development of persistent pro-inflammatory responses that contribute to atherosclerosis, metabolic syndrome, cancer and frailty1-3. The ageing brain is also vulnerable to inflammation, as demonstrated by the high prevalence of age-associated cognitive decline and Alzheimer's disease4-6. Systemically, circulating pro-inflammatory factors can promote cognitive decline7,8, and in the brain, microglia lose the ability to clear misfolded proteins that are associated with neurodegeneration9,10. However, the underlying mechanisms that initiate and sustain maladaptive inflammation with ageing are not well defined. Here we show that in ageing mice myeloid cell bioenergetics are suppressed in response to increased signalling by the lipid messenger prostaglandin E2 (PGE2), a major modulator of inflammation11. In ageing macrophages and microglia, PGE2 signalling through its EP2 receptor promotes the sequestration of glucose into glycogen, reducing glucose flux and mitochondrial respiration. This energy-deficient state, which drives maladaptive pro-inflammatory responses, is further augmented by a dependence of aged myeloid cells on glucose as a principal fuel source. In aged mice, inhibition of myeloid EP2 signalling rejuvenates cellular bioenergetics, systemic and brain inflammatory states, hippocampal synaptic plasticity and spatial memory. Moreover, blockade of peripheral myeloid EP2 signalling is sufficient to restore cognition in aged mice. Our study suggests that cognitive ageing is not a static or irrevocable condition but can be reversed by reprogramming myeloid glucose metabolism to restore youthful immune functions.
View details for DOI 10.1038/s41586-020-03160-0
View details for PubMedID 33473210
AHR Regulates NK Cell Migration via ASB2-Mediated Ubiquitination of Filamin A.
Frontiers in immunology
2021; 12: 624284
Natural killer (NK) cells are effector cells of the innate immune system involved in defense against virus-infected and transformed cells. The effector function of NK cells is linked to their ability to migrate to sites of inflammation or damage. Therefore, understanding the factors regulating NK cell migration is of substantial interest. Here, we show that in the absence of aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, NK cells have reduced capacity to migrate and infiltrate tumors in vivo. Analysis of differentially expressed genes revealed that ankyrin repeat and SOCS Box containing 2 (Asb2) expression was dramatically decreased in Ahr -/- NK cells and that AhR ligands modulated its expression. Further, AhR directly regulated the promoter region of the Asb2 gene. Similar to what was observed with murine Ahr -/- NK cells, ASB2 knockdown inhibited the migration of human NK cells. Activation of AHR by its agonist FICZ induced ASB2-dependent filamin A degradation in NK cells; conversely, knockdown of endogenous ASB2 inhibited filamin A degradation. Reduction of filamin A increased the migration of primary NK cells and restored the invasion capacity of AHR-deficient NK cells. Our study introduces AHR as a new regulator of NK cell migration, through an AHR-ASB2-filamin A axis and provides insight into a potential therapeutic target for NK cell-based immunotherapies.
View details for DOI 10.3389/fimmu.2021.624284
View details for PubMedID 33717133
GD2 is a macrophage checkpoint molecule and combined GD2/CD47 blockade results in synergistic effects and tumor clearance in xenograft models of neuroblastoma and osteosarcoma
AMER ASSOC CANCER RESEARCH. 2020: 35
View details for Web of Science ID 000551367400035
Combining RNA in situ hybridization and spectral flow cytometry to investigate the leukocyte glycocalyx in autoimmunity
AMER ASSOC IMMUNOLOGISTS. 2020
View details for Web of Science ID 000589972402250
Reprogramming leukemia cells into antigen presenting cells as a novel cancer vaccination immunotherapy
AMER ASSOC IMMUNOLOGISTS. 2020
View details for Web of Science ID 000589972400640
Hyaluronan synthesis inhibition impairs antigen presentation and delays transplantation rejection.
Matrix biology : journal of the International Society for Matrix Biology
A coat of pericellular hyaluronan surrounds mature dendritic cells (DC) and contributes to cell-cell interactions. We asked whether 4-methylumbelliferone (4MU), an oral inhibitor of HA synthesis, could inhibit antigen presentation. We find that 4MU treatment reduces pericellular hyaluronan, destabilizes interactions between DC and T-cells, and prevents T-cell proliferation in vitro and in vivo. These effects were observed only when 4MU was added prior to initial antigen presentation but not later, consistent with 4MU-mediated inhibition of de novo antigenic responses. Building on these findings, we find that 4MU delays rejection of allogeneic pancreatic islet transplant and allogeneic cardiac transplants in mice and suppresses allogeneic T-cell activation in human mixed lymphocyte reactions. We conclude that 4MU, an approved drug, may have benefit as an adjunctive agent to delay transplantation rejection.
View details for DOI 10.1016/j.matbio.2020.12.001
View details for PubMedID 33290836
Enasidenib drives human erythroid differentiation independently of isocitrate dehydrogenase 2.
The Journal of clinical investigation
Cancer-related anemia is present in over 60% of newly diagnosed cancer patients and is associated with substantial morbidity and high medical costs. Drugs that enhance erythropoiesis are urgently required to decrease transfusion rates and improve quality of life. Clinical studies have observed an unexpected improvement in hemoglobin and red blood cell (RBC) transfusion-independence in AML patients treated with the isocitrate dehydrogenase 2 (IDH2) mutant-specific inhibitor, enasidenib, leading to improved quality of life without a reduction in AML disease burden. Here, we demonstrate that enasidenib enhanced human erythroid differentiation of hematopoietic progenitors. The phenomenon was not observed with other IDH1/2 inhibitors and occurred in IDH2-deficient CRIPSR-engineered progenitors independently of D-2-hydroxyglutarate. The effect of enasidenib on hematopoietic progenitors was mediated by protoporphyrin accumulation, driving heme production and erythroid differentiation in committed CD71+ progenitors rather than hematopoietic stem cells. Our results position enasidenib as a promising therapeutic agent for improvement of anemia and provide the basis for a clinical trial using enasidenib to decrease transfusion dependence in a wide array of clinical contexts.
View details for DOI 10.1172/JCI133344
View details for PubMedID 31895700
- Reprogramming Leukemia Cells into Antigen Presenting Cells As a Novel Cancer Vaccination Immunotherapy AMER SOC HEMATOLOGY. 2019
- CAR T Cells Targeting B7-H3, a Pan-Cancer Antigen, Demonstrate Potent Preclinical Activity Against Pediatric Solid Tumors and Brain Tumors CLINICAL CANCER RESEARCH 2019; 25 (8): 2560–74
CAR T cells targeting B7-H3, a Pan-Cancer Antigen, Demonstrate Potent Preclinical Activity Against Pediatric Solid Tumors and Brain Tumors.
Clinical cancer research : an official journal of the American Association for Cancer Research
PURPOSE: Patients with relapsed pediatric solid tumors and CNS malignancies have few therapeutic options and frequently die of their disease. Chimeric antigen receptor (CAR) T cells have shown tremendous success in treating relapsed pediatric acute lymphoblastic leukemia, but this has not yet translated to treating solid tumors. This is partially due to a paucity of differentially expressed cell surface molecules on solid tumors that can be safely targeted. Here, we present B7-H3 (CD276) as a putative target for CAR T cell therapy of pediatric solid tumors, including those arising in the central nervous system.EXPERIMENTAL DESIGN: We developed a novel B7-H3 CAR whose binder is derived from a monoclonal antibody that has been shown to preferentially bind tumor tissues and has been safely used in humans in early phase clinical trials. We tested B7-H3 CAR T cells in a variety of pediatric cancer models.RESULTS: B7-H3 CAR T cells mediate significant anti-tumor activity in vivo, causing regression of established solid tumors in xenograft models including osteosarcoma, medulloblastoma, and Ewing sarcoma. We demonstrate that B7-H3 CAR T cell efficacy is largely dependent upon high surface target antigen density on tumor tissues and that activity is greatly diminished against target cells that express low levels of antigen, thus providing a possible therapeutic window despite low-level normal tissue expression of B7-H3.CONCLUSIONS: B7-H3 CAR T cells could represent an exciting therapeutic option for patients with certain lethal relapsed or refractory pediatric malignancies which should be tested in carefully designed clinical trials.
View details for PubMedID 30655315
- REPROGRAMMING OF PRIMARY HUMAN PHILADELPHIA CHROMOSOME-POSITIVE B CELL ACUTE LYMPHOBLASTIC LEUKEMIA CELLS INTO NONLEUKEMIC MACROPHAGES ELSEVIER SCIENCE INC. 2016: S67