Employing Familial AD Induced Pluripotent Stem Cells to Study Neurodegeneration

Summary

Principal Investigator: Suman Jayadev
Abstract: DESCRIPTION (provided by applicant): The rising global prevalence of Alzheimer disease (AD) has heightened the urgency to develop effective AD therapeutics. Despite extraordinary efforts, we have been less than successful to curb either the progression or initiation of AD through drug therapy. To do so, we need a stronger understanding of the fundamental elements of AD pathobiology. The multifactorial nature of AD pathogenesis is becoming increasing clear and thus we can benefit from a broad approach to understanding disease mechanisms for effective therapeutic targeting. Recent advances have revealed factors such as partial loss of presenilin function and non-cell autonomous interactions which may contribute to AD pathogenesis. For example, murine models in which both presenilin genes are absent in forebrain neurons develop AD-like neuropathological and clinical features including neurodegeneration. We have demonstrated that presenilin 2 (PSEN2) deficiency is associated with an exaggerated pro-inflammatory response in microglia and that the fAD associated PSEN2 N141I mutation leads to decreased gamma- secretase activity in microglia. We have also reported a novel AD associated PSEN2 mutation that leads to decreased c-terminus Presenilin 2 (PS2) protein, further supporting the hypothesis that PSEN2 loss of function contributes to AD. These findings in conjunction with the lack of success thus far of gamma secretase inhibitors in clinical trials and recent reports on partial loss of PSEN1 function associated with AD raise a critical question regarding the pathogenesis of AD. In addition to neuronal A[unreadable]42 production what additional mechanisms are involved in AD pathogenesis? The dynamics and significance of A[unreadable]42 production are being investigated;however, decreased CNS A[unreadable] clearance itself has been implicated in AD. Microglia, are key mediators of A[unreadable] clearance. Therefore altered microglia behavior, as we observed with PS2 deficiency, may play a critical non-cell autonomous role in AD pathogenesis. Taking all recently available data into consideration, we hypothesize that AD pathogenesis involves combinatorial dysfunction in multiple cell types and that PSEN2 fAD mutations contribute to disease through toxic-loss-of-function in addition to the previously described toxic-gain-of-function. The goal of our laboratory is to study cell autonomous and non-cell autonomous mechanisms of neuronal injury in AD. We are pursuing an R01 funded project examining the impact of PSEN2 mutations on microglia and neuroinflammation as it relates to non-cell autonomous neurodegeneration in AD. To bolster the significance and human disease relevance of the R01 project, we are developing additional techniques in our research program with exciting potential to address these hypotheses. The use of patient derived induced pluripotent stem cells (iPSCs) is an expedient approach to examine the molecular phenotype of specific mutations as well as their cell type specific effects. At the University of Washington (UW), we are uniquely positioned to address the questions posed above by employing several key resources. First, the UW Alzheimer Disease Research Center (ADRC) has banked fibroblasts from well-characterized fAD cohorts. Second, we have access to established facilities for the derivation and characterization of induced pluripotent stem cell (iPSC) lines. We have created multiple iPSC lines which are being fully characterized molecularly, epigenetically and for capacity for teratoma formation among other crucial iPSC requirements. The impact of fAD mutations on iPSC derived glial cells and the effect of specific PSEN2 mutations on the biology of any neural cell type has not been reported. In this K02 proposal, I aim to collaborate with iPSC pioneers in the field with dual purpose to 1) develop a new skill set for my career development and 2) contribute unique information about PSEN2 fAD mutations and identify potential pathways where neuronal and glial cell processes may interact, leading to neurodegeneration. Thus, we propose the following experimental plan. We will investigate the cell type specific effects of two different PSEN2 mutations that cause fAD. We hypothesize that AD associated PSEN2 mutations lead to partial loss of PSEN2 function that will alter the behavior of neurons and microglia. To address this hypothesis we will: A) Generate, characterize and assess APP processing activity in iPSC lines from patient fibroblasts containing PS2 mutations. B) Differentiate iPSCs containing PSEN2 N141I or PSEN2 deletion mutation (PS2del) into neurons. Determine the effects of PS2 deletion on intrinsic electrophysiological properties, synaptic physiology and gamma secretase activity of these neurons. C) Differentiate the iPSC lines used in 1B into microglia and evaluate for pro-inflammatory cytokine release, phagocytosis and inflammatory pathway signaling. Next, we will study the non-cell autonomous impact of fAD PS2 mutations on the interaction between neurons and glia. We hypothesize that these two PS2 mutations contribute to AD through consequences of glial dysfunction leading to neuronal injury. By employing neuronal-glial co-cultures we will study neuronal processes in the presence of PS2 fAD mutation carrying microglia. We will: A) Measure wildtype neuronal synaptic physiology in the absence and presence of A[unreadable]42 when cocultured with wildtype or PS2 fAD microglia. B) Assess neuronal susceptibility to neurotoxicity in the presence of wildtype or PS2 fAD microglia.
Funding Period: 2013-08-15 - 2018-07-31
more information: NIH RePORT

Detail Information

Research Grants30

  1. Alzheimer's Disease Research Center at Columbia University
    Scott A Small; Fiscal Year: 2013
    ..HIPAA compliant data organization and statistical consulting services are provided under the ADRC to the research community at Columbia and external to it. ..
  2. Sleep/Wake Fragmentation with Age: Molecular Mechanisms
    ALLAN IAN PACK; Fiscal Year: 2013
    ..These three projects are supported by three cores;a) Administrative Core;b) Mouse Behavioral Core;and c) Biostatistics and Bioinformatics Core. ..
  3. Role of phosphoinositides in neuronal membrane traffic and neurodegeneration
    GILBERT DIPAOLO; Fiscal Year: 2013
    ..We anticipate that our studies will provide key insights into the biology of APP and Tau as well as a better understanding of the role of lipid dysregulation in AD pathogenesis. ..
  4. Presenilin 2 and Neuroinflammation
    Suman Jayadev; Fiscal Year: 2013
    ....
  5. Rush Alzheimer's Disease Core Center
    David Alan Bennett; Fiscal Year: 2013
    ..The Data Management and Biostatistics Core, begun in 1995, will continue to support all other Cores with PC- and web-based services and processes, and provide statistical support to users of Rush ADCC resources. ..
  6. Presenilin Variants in the Modulation of Hippocampal Neurogenesis
    Sangram S Sisodia; Fiscal Year: 2013
    ..abstract_text> ..
  7. ApoE Receptor Biology and Neurodegeneration
    Mary Jo Ladu; Fiscal Year: 2013
    ..This Program will thus provide new and valuable information about how apoE and apoE receptors affect the pathogenesis of Alzheimer's disease. ..
  8. Gamma-Secretase and Myelin: A Paradigm Shift in Brain Disorders
    Gang Yu; Fiscal Year: 2013
    ..As such this work represents a new way of thinking about brain functions and disorders. ..
  9. Calcineurin/NFAT signaling in pathogenesis of neurodegeneration in Down Syndrome
    Isabella A Graef; Fiscal Year: 2013
    ..We will test whether two additional genes synergize with APP. If this hypothesis is correct it might enable us to develop new treatments for some aspects of the disabling midlife deterioration of cognitive abilities in DS patients. ..
  10. Human induced neuronal stem cell models of familial Alzheimer's disease
    Asa Abeliovich; Fiscal Year: 2013
    ..2) Directed reprogramming tools that may be broadly applied to the study of neurological disease. ..
  11. CXCL8-mediated glial cross-talk and neuroprotection in HIV-1 Dementia
    Anuja Ghorpade; Fiscal Year: 2013
    ..abstract_text> ..
  12. Center for Excellence in Diabetes and Obesity Research
    ARUNI BHATNAGAR BHATNAGAR; Fiscal Year: 2013
    ..Continued support to the Center will strengthen the infrastructure of biomedical research at the University of Louisville and will positively impact the field of diabete and obesity research worldwide. ..
  13. Selective over expression of TDP-43 in APP/PS1 mice alters APP processing
    MICHAEL ANDRE GITCHO; Fiscal Year: 2013
    ..This in vivo model potentially could lead to the development of new therapeutics targeted at slowing the progression. ..
  14. APP/AB/Tau biochemistry in transgenic mice, familial and sporadic AD
    Alex E Roher; Fiscal Year: 2013
    ..A more complete understanding of AD molecular phenotypes and their clinical responses will aid in the discovery and application of efficacious treatments that will prevent AD or enhance the quality of life of AD patients. ..
  15. CNS injury caused by HIV-1 and alcohol: Protective effects of CB2 activation
    Yuri Persidsky; Fiscal Year: 2013
    ..abstract_text> ..
  16. The Role of CX3CR1 Signaling in Alzheimer's Disease Pathogenesis
    Sungho Lee; Fiscal Year: 2013
    ..In Specific Aim 3, Cx3cr1-deficient microglia will be examined for their capacity to phagocytose A-beta and migrate to stereotactically injected A-beta. ..
  17. Expanding the National Health Accounts
    David M Cutler; Fiscal Year: 2013
    ..Establishment of a set of national health accounts will allow us as a society to understand which medical interventions improve the health of the U.S. population most efficiently. ..
  18. Molecular Mechanisms linking Aging, Abeta Proteotoxicity and Neurodegeneration
    Jeffery W Kelly; Fiscal Year: 2013
    ..abstract_text> ..
  19. Northeast Biodefense Center
    W Ian Lipkin; Fiscal Year: 2013
    ..As a Center based in a School of Public Health and a State Department of Health, the NBC has a firm commitment to and practical understanding of Emergency Preparedness. ..
  20. Role of Microglia in Ethanol-induced Oxidative Stress
    Stanley M Stevens; Fiscal Year: 2013
    ....
  21. NW Research Center for Excellence in Biodefense and Emerging Infectious Diseases
    Samuel I Miller; Fiscal Year: 2013
    ..abstract_text> ..
  22. Wisconsin Alzheimer's Disease Research Center
    Sanjay Asthana; Fiscal Year: 2013
    ..abstract_text> ..
  23. ALZHEIMER DISEASE RESEARCH CENTER
    HELENA CHANG CHUI; Fiscal Year: 2013
    ..abstract_text> ..
  24. UCLA Alzheimer's Disease Research Center
    David B Teplow; Fiscal Year: 2013
    ..Innovations in advancing research are proposed in each Core of this proposal. Each core has responded to criticisms and recommendations from the 2008 review in this renewal application. ..
  25. Presenilin dysfunction in the brain
    Raymond J Kelleher; Fiscal Year: 2013
    ....
  26. Alzheimer's Disease Research Center
    Mary Sano; Fiscal Year: 2013
    ..abstract_text> ..
  27. ALZHEIMERS DISEASE RESEARCH CENTER
    John Morris; Fiscal Year: 2013
    ..Changing tau protein levels and tau protein isoforms in mouse models of dementia;(Timothy Miller) 3. APOE metabolism in AD and controls;(Randall Bateman). ..
  28. Phospholipase D1 in Alzheimer???s Precursor Protein trafficking and processing
    KIMBERLY SHAUNTAE POINT DU JOUR; Fiscal Year: 2013
    ....