Submission
| Title: | Peripheral blood mononuclear cells to study SHIP1 inhibitors as a therapeutic in Alzheimer’s disease |
| Co-Authors: |
Lee-Gosselin, Audrey, Department of Neurology, Indiana University School of Medicine; Kristen Ann Russ, Department of Medical and Molecular Genetics, Indiana University School of Medicine; Mia Fleisher-de Kozan, Department of Biological Sciences, Purdue University; Steve Brown, Department of Biostatistics and Health Data Science, Indiana University School of Medicine; Cynthia Jesudason, Lgenia, 412 S Maple Street, Fortville, IN;, Emily Mason, Department of Clinical Pharmacology, Indiana University School of Medicine; , Liana Apostolova, Department of Neurology, Indiana University School of Medicine; Kelly Nicole Holohan Nudelman, Department of Medical and Molecular Genetics, Indiana University School of Medicine; Andrew Saykin, Department of Radiology and Imaging Sciences, Indiana University School of Medicine; Shaoyou Chu, Department of Clinical Pharmacology, Indiana University School of Medicine; Timothy Richardson, Department of Clinical Pharmacology, Indiana University School of Medicine; Alan Palkowitz, Department of Clinical Pharmacology, Indiana University School of Medicine; Jeffrey Dage, Department of Neurology, Indiana University School of Medicine |
Abstract
Background/Significance/Rationale: Several genetic risk factors are associated with Alzheimer’s disease (AD), and many of these are microglia specific genes, the brain resident macrophages directly involved in neuroinflammation. The inositol polyphosphate-5-phosphatase (INPP5D) locus, also known as SHIP1, has a single nucleotide polymorphism (rs35349669) that is associated with increased risk of developing late-onset AD. SHIP1 is thought to be involved in phagocytosis and cytokine release. There are very few blood-based biomarkers for neuroinflammatory targets. Therefore, we sought to identify markers related to modulation of SHIP1 in human peripheral blood mononuclear cells (hPBMCs), which would serve as measures of target engagement as these molecules advance to clinical trials.
Methods: hPBMCs were seeded at 1 million cells per well. After an overnight incubation, 10 µM SHIP1 inhibitor, or DMSO (control), was added to the cells. After 24h, the cell media was collected, the cells were washed in PBS and frozen for RNA extraction. Cytokine release in the cell media was measured using Ella and MSD, and gene expression in the PI3K pathway was measured with NanoString nCounter panel Vantage 3D RNA MAPK PI3K Pathways
Results/Findings: We find that pro-inflammatory cytokines CCL2 and TNF-α are decreased with SHIP1 inhibitor. We observe an increase in the low-density lipoprotein receptor (LDLR) gene expression with SHIP1 inhibitor.
Conclusions/Discussion: LDLR is thought to play a role in phagocytosis of amyloid through interactions with APOE associated plaques and follow up experiments are underway to connect peripheral and central changes in vivo.
Translational/Human Health Impact: Our work could help identify blood-based biomarkers for neuroinflammatory targets in early diagnostic of neurodegenerative diseases such as Alzheimer’s disease. Specifically, we are looking to identify markers related to SHIP1 modulation using SHIP1 inhibitors which are drug targets for AD.
