Biology subjects

Lane, S. D.

Publications and source records attributed to Lane, S. D..

3 recordsLinked to original sources

bioRxiv2022

iPSC-Derived PSEN2 (N141I) Astrocytes and Microglia Exhibit a Primed Inflammatory Phenotype

BackgroundWidescale evidence points to the involvement of glia and immune pathways in the progression of Alzheimers disease (AD). AD-associated iPSC-derived glial cells show a diverse range of AD-related phenotypic states encompassing cytokine/chemokine release, phagocytosis and morphological profiles, but to date studies are limited to cells derived from PSEN1, APOE and APP mutations or sporadic patients. The aim of the current study was to successfully differentiate iPSC-derived microglia and astrocytes from patients harbouring an AD-causative PSEN2 (N141I) mutation and characterise the inflammatory and morphological profile of these cells. MethodsiPSCs from three healthy control individuals and three familial AD patients harbouring a heterozygous PSEN2 (N141I) mutation were used to derive astrocytes and microglia-like cells and cell identity and morphology were characterised through immunofluorescent microscopy. Cellular characterisation involved the stimulation of these cells by LPS and A{beta}42 and analysis of cytokine/chemokine release was conducted through ELISAs and multi-cytokine arrays. The phagocytic capacity of these cells was then indexed by the uptake of fluorescently labelled fibrillar A{beta}42. ResultsAD-derived astrocytes and microglia-like cells exhibited an atrophied and less complex morphological appearance than healthy controls. AD-derived astrocytes showed increased basal expression of GFAP, S100{beta} and increased secretion and phagocytosis of A{beta}42 while AD-derived microglia-like cells showed decreased IL-8 secretion compared to healthy controls. Upon immunological challenge AD-derived astrocytes and microglia-like cells show exaggerated secretion of the pro-inflammatory IL-6, CXCL1, ICAM-1 and IL-8 from astrocytes and IL-18 and MIF from microglia. ConclusionOur study showed, for the first time, the differentiation and characterisation of iPSC-derived astrocytes and microglia-like cells harbouring a PSEN2 (N141I) mutation. PSEN2 (N141I)-mutant astrocytes and microglia-like cells presented with a primed phenotype characterised by reduced morphological complexity, exaggerated pro-inflammatory cytokine secretion and altered A{beta}42 production and phagocytosis.

neuroscience↗

bioRxiv2022

3D Bioprinting of Stem Cell-Derived Central Nervous System Cells Enables Astrocyte Growth, Vasculogenesis and Enhances Neural Differentiation/Function

Current research tools for pre-clinical drug development such as rodent models and 2D immortalised monocultures have failed to serve as effective translational models for human CNS disorders. Recent advancements in the development of iPSCs and 3D culturing can improve the in vivo-relevance of pre-clinical models, while generating 3D cultures though novel bioprinting technologies can offer increased scalability and replicability. As such, there is a need to develop platforms that combine iPSC-derived cells with 3D bioprinting to produce scalable, tunable and biomimetic cultures for preclinical drug discovery applications. We report a biocompatible PEG-based matrix which incorporates RGD and YIGSR peptide motifs and full length collagen IV at a stiffness similar to the human brain (1.5 kPa). Using a high-throughput commercial bioprinter we report the viable culture and morphological development of iPSC-derived astrocytes, brain microvascular endothelial cells, neural progenitors and neurons in our novel matrix. We also show that this system supports endothelial vasculogenesis and enhances neural differentiation and spontaneous activity. This platform forms a foundation for more complex, multicellular models to facilitate high-throughput translational drug discovery for CNS disorders.

neuroscience↗

bioRxiv2018

Measures of Possible Allostatic Load in Comorbid Cocaine and Alcohol use Disorder: Brain White Matter Integrity, Telomere Length, and Anti-Saccade Performance

Chronic cocaine and alcohol use impart significant stress on biological and cognitive systems, resulting in changes consistent with an allostatic load model of neurocognitive impairment. The present study measured potential markers of allostatic load in individuals with comorbid cocaine/alcohol use disorders (CUD/AUD) and control subjects. Measures of brain white matter (WM) integrity, telomere length, and impulsivity/attentional bias were obtained. WM integrity (CUD/AUD only) was indexed by diffusion tensor imaging metrics, including radial diffusivity (RD) and fractional anisotropy (FA). Telomere length was indexed by T/S ratio. Impulsivity and attentional bias to drug cues were measured via eye-tracking, and were also modeled using the Hierarchical Diffusion Drift Model (HDDM). Average whole-brain RD and FA were associated with years of cocaine use (R2 = 0.56 and 0.51, both p < .005) but not years of alcohol use. CUD/AUD subjects showed more anti-saccade errors (p < .01), greater attentional bias scores (p < .001), and higher HDDM drift rates on cocaine-cue trials (Bayesian probability CUD/AUD > control = p > 0.99). Telomere length was shorter in CUD/AUD, but the difference was not statistically significant. Within the CUD/AUD group, exploratory regression using an elastic-net model determined that more years of cocaine use, older age, larger HDDM drift rate differences and shorter telomere length were all predictive of white matter integrity as measured by RD (model R2 = 0.79). Collectively, the results provide modest support linking CUD/AUD to putative markers of allostatic load.

neuroscience↗