26 research outputs found
Pathogenic Angiogenic Mechanisms in Alzheimer\u27s Disease
Vascular dysfunction is a crucial pathological hallmark of Alzheimer\u27s disease (AD). Studies have reported that beta amyloid (Aβ) causes increased blood vessel growth in the brains of AD mouse models, a phenomenon that is also seen in AD patients. This has given way to an alternative angiogenesis hypothesis according to which, increased leakiness in the blood vessels disrupts the blood‐brain barrier (BBB) and allows unwanted blood products to enter the brain causing progression of disease pathology, promoting amyloid clumping and aggregation along with impaired cerebral blood flow. Furthermore, the expression of melanotransferrin in AD model and patients may contribute to angiogenesis. The objective of this chapter is to attempt to establish a link between the vascular damage and AD pathology. Curbing the vascular changes and resulting damage seen in the brains of AD model mice and improving their cognition by treating with FDA‐approved anti‐angiogenic drugs may expedite the translational potential of this research into clinical trials in human patients. This direction into targeting angiogenesis will facilitate new preventive and therapeutic interventions for AD and related vascular diseases
Discovery of a Highly Conserved Peptide in the Iron Transporter Melanotransferrin that Traverses an Intact Blood Brain Barrier and Localizes in Neural Cells
The blood-brain barrier (BBB) hinders the distribution of therapeutics intended for treatment of diseases of the brain. Our previous studies demonstrated that that a soluble form of melanotransferrin (MTf; Uniprot P08582; also known as p97, MFI2, and CD228), a mammalian iron-transport protein, is an effective carrier for delivery of drug conjugates across the BBB into the brain and was the first BBB targeting delivery system to demonstrate therapeutic efficacy within the brain. Here, we performed a screen to identify peptides from MTf capable of traversing the BBB. We identified a highly conserved 12-amino acid peptide, termed MTfp, that retains the ability to cross the intact BBB undigested, distribute throughout the parenchyma, and enter endosomes and lysosomes within neurons, astrocytes and microglia in the brain. This peptide may provide a platform for the transport of therapeutics to the CNS, and thereby offers new avenues for potential treatments of neuropathologies that are currently refractory to existing therapies
Curcuphenol possesses an unusual histone deacetylase enhancing activity that counters immune escape in metastatic tumours
Curcuphenol, a common component of the culinary spices, naturally found in marine invertebrates and plants, has been identified as a novel candidate for reversing immune escape by restoring expression of the antigen presentation machinery (APM) in invasive cancers, thereby resurrecting the immune recognition of metastatic tumours. Two synthetic curcuphenol analogues, were prepared by informed design that demonstrated consistent induction of APM expression in metastatic prostate and lung carcinoma cells. Both analogues were subsequently found to possess a previously undescribed histone deacetylase (HDAC)-enhancing activity. Remarkably, the H3K27ac ChIPseq analysis of curcuphenol-treated cells reveals that the induced epigenomic marks closely resemble the changes in genome-wide pattern observed with interferon-γ, a cytokine instrumental for orchestrating innate and adaptive immunity. These observations link dietary components to modifying epigenetic programs that modulate gene expression guiding poised immunity
Lipolysis drives expression of the constitutively active receptor GPR3 to induce adipose thermogenesis
Thermogenic adipocytes possess a therapeutically appealing, energy-expending capacity, which is canonically cold-induced by ligand-dependent activation of β-adrenergic G protein-coupled receptors (GPCRs). Here, we uncover an alternate paradigm of GPCR-mediated adipose thermogenesis through the constitutively active receptor, GPR3. We show that the N terminus of GPR3 confers intrinsic signaling activity, resulting in continuous Gs-coupling and cAMP production without an exogenous ligand. Thus, transcriptional induction of Gpr3 represents the regulatory parallel to ligand-binding of conventional GPCRs. Consequently, increasing Gpr3 expression in thermogenic adipocytes is alone sufficient to drive energy expenditure and counteract metabolic disease in mice. Gpr3 transcription is cold-stimulated by a lipolytic signal, and dietary fat potentiates GPR3-dependent thermogenesis to amplify the response to caloric excess. Moreover, we find GPR3 to be an essential, adrenergic-independent regulator of human brown adipocytes. Taken together, our findings reveal a noncanonical mechanism of GPCR control and thermogenic activation through the lipolysis-induced expression of constitutively active GPR3.ISSN:0092-8674ISSN:1097-417
Adjusting the compass: new insights into the role of angiogenesis in Alzheimer’s disease
A novel type-2 innate lymphoid cell-based immunotherapy for cancer
Cell-based cancer immunotherapy has achieved significant advancements, providing a source of hope for cancer patients. Notwithstanding the considerable progress in cell-based immunotherapy, the persistently low response rates and the exorbitant costs associated with their implementation still present a formidable challenge in clinical settings. In the landscape of cell-based cancer immunotherapies, an uncharted territory involves Type 2 innate lymphoid cells (ILC2s) and interleukin-33 (IL-33) which promotes ILC2 functionality, recognized for their inherent ability to enhance immune responses. Recent discoveries regarding their role in actuating cytolytic T lymphocyte responses, including curbing tumor growth rates and hindering metastasis, have added a new dimension to our understanding of the IL-33/ILC2 axis. These recent insights may hold significant promise for ILC2 cell-based immunotherapy. Nevertheless, the prospect of adoptively transferring ILC2s to confer immune protection against tumors has yet to be investigated. The present study addresses this hypothesis, revealing that ILC2s isolated from the lungs of tumor-bearing mice, and tumor infiltrating ILC2s when adoptively transferred after tumor establishment at a ratio of one ILC2 per sixty tumor cells, leads to an influx of tumor infiltrating CD4+ and CD8+ T lymphocytes as well as tumor infiltrating eosinophils resulting in a remarkable reduction in tumor growth. Moreover, we find that post-adoptive transfer of ILC2s, the number of tumor infiltrating ILC2s is inversely proportional to tumor size. Finally, we find corollaries of the IL-33/ILC2 axis enhancing the infiltration of eosinophils in human prostate carcinomas patients' expressing high levels of IL-33 versus those expressing low levels of IL-33. Our results underscore the heightened efficacy of adoptively transferred ILC2s compared to alternative approaches, revealing an approximately one hundred fifty-fold superiority on a cell-per-cell basis over CAR T-cells in the specific targeting and elimination of tumors within the same experimental model. Overall, this study demonstrates the functional significance of ILC2s in cancer immunosurveillance and provides the proof of concept of the potential utility of ILC2 cell-based cancer immunotherapies
Serum free culture for the expansion and study of type 2 innate lymphoid cells
Abstract Type 2 innate lymphoid cells (ILC2s) were discovered approximately ten years ago and their clinical relevance is gaining greater importance. However, their successful isolation from mammalian tissues and in vitro culture and expansion continues to pose challenges. This is partly due to their scarcity compared to other leukocyte populations, but also because our current knowledge of ILC2 biology is incomplete. This study is focused on ST2+ IL-25Rlo lung resident ILC2s and demonstrate for the first time a methodology allowing mouse type 2 innate lymphoid cells to be cultured, and their numbers expanded in serum-free medium supplemented with Interleukins IL-33, IL-2, IL-7 and TSLP. The procedures described methods to isolate ILC2s and support their growth for up to a week while maintaining their phenotype. During this time, they significantly expand from low to high cell concentrations. Furthermore, for the first time, sub-cultures of primary ILC2 purifications in larger 24- and 6-well plates were undertaken in order to compare their growth in other media. In culture, ILC2s had doubling times of 21 h, a growth rate of 0.032 h−1 and could be sub-cultured in early or late phases of exponential growth. These studies form the basis for expanding ILC2 populations that will facilitate the study and potential applications of these rare cells under defined, serum-free conditions
Type 2 Innate Lymphocytes Actuate Immunity Against Tumours and Limit Cancer Metastasis
Abstract Type 2 innate lymphoid cells (ILC2) potentiate immune responses, however, their role in mediating adaptive immunity in cancer has not been assessed. Here, we report that mice genetically lacking ILC2s have significantly increased tumour growth rates and conspicuously higher frequency of circulating tumour cells (CTCs) and resulting metastasis to distal organs. Our data support the model that IL-33 dependent tumour-infiltrating ILC2s are mobilized from the lungs and other tissues through chemoattraction to enter tumours, and subsequently mediate tumour immune-surveillance by cooperating with dendritic cells to promote adaptive cytolytic T cell responses. We conclude that ILC2s play a fundamental, yet hitherto undescribed role in enhancing anti-cancer immunity and controlling tumour metastasis
The role of the innate immune response regulatory gene ABCF1 in mammalian embryogenesis and development.
ABCF1 is an ABC transporter family protein that has been shown to regulate innate immune response and is a risk gene for autoimmune pancreatitis and arthritis. Unlike other members of ABC transporter family, ABCF1 lacks trans-membrane domains and is thought to function in translation initiation through an interaction with eukaryotic translation initiation factor 2 (eIF2). To study ABCF1 expression and function in development and disease, we used a single gene trap insertion in the Abcf1 gene in murine embryonic stem cells (ES cells) that allowed lineage tracing of the endogenous Abcf1 promoter by following the expression of a β-galactosidase reporter gene. From the ES cells, heterozygous mice (Abcf1+/-) were produced. No live born Abcf1-/- progeny were ever generated, and the lethality was not mouse strain-specific. Thus, we have determined that Abcf1 is an essential gene in development. Abcf1-/- mice were found to be embryonic lethal at 3.5 days post coitum (dpc), while Abcf1+/- mice appeared developmentally normal. Abcf1+/- mice were fertile and showed no significant differences in their anatomy when compared with their wild type littermates. The Abcf1 promoter was found to be active in all organs in adult mice, but varies in levels of expression in specific cell types within tissues. Furthermore, we observed high promoter activity in the blastocysts and embryos. Overall, Abcf1 expression in embryos is required for development and its expression in adults was highly correlated with actively proliferating and differentiating cell types