Biology subjects

Trescott, S.

Publications and source records attributed to Trescott, S..

3 recordsLinked to original sources

bioRxiv2025

Investigation of CNS damage following HIV infection and methamphetamine exposure using human iPSC-derived microglia and 3D cerebral assembloid models

HIV-associated neurocognitive disorder (HAND) is characterized by glial activation and neuroinflammation emerging from HIV infection. Moreover, methamphetamine (METH) is a highly addictive psychostimulant whose use is linked to high HIV prevalence, significantly worsening clinical outcomes for people living with HIV and hastening onset of systemic illness. Overall, pathologies associated with HIV infection/METH use comorbidity include neuroinflammation, neurotoxicity, synaptodendritic damage, and resulting cognitive dysfunction. However, mechanisms underlying this neuropathogenesis remain elusive due to the scarcity of human brain-specific experimental model systems. Therefore, we created a next-generation three-dimensional (3D) human brain model derived from human induced pluripotent stem cells (hiPSCs). Specifically, this 3D in vitro cerebral assembloid model integrates functional microglia derived from hiPSCs with cerebral organoids. Microglia are key contributors to HAND symptoms associated with HIV/METH comorbidity. We show that the presence of microglia in this assembloid model allows productive infection with HIV, which is enhanced by METH exposure, resulting in increased glial activation, inflammatory responses (namely IL-1{beta} and IL-6 release), and neurotoxicity marked by neuronal cell death and synaptic protein loss. Importantly, in this model, we observed markedly decreased levels of the microglial receptor TREM2, which is implicated in microglial functions including phagocytosis, apoptosis and inflammatory responses following HIV infection and METH treatment. Analysis of our model showed that decreased TREM2 function may lead to HIV- and METH-associated pathological changes. Overall, our assembloid model could be a valuable tool for future analyses of HIV/METH/CNS interactions and mechanisms underlying HAND, which could lead to novel therapeutic approaches to decreasing the CNS viral reservoir.

neuroscience↗

bioRxiv2021

Profiling Transcription Initiation in Peripheral Leukocytes Reveals Severity-Associated Cis-Regulatory Elements in Critical COVID-19

The contribution of transcription factors (TFs) and gene regulatory programs in the immune response to COVID-19 and their relationship to disease outcome is not fully understood. Analysis of genome-wide changes in transcription at both promoter-proximal and distal cis-regulatory DNA elements, collectively termed the active cistrome, offers an unbiased assessment of TF activity identifying key pathways regulated in homeostasis or disease. Here, we profiled the active cistrome from peripheral leukocytes of critically ill COVID-19 patients to identify major regulatory programs and their dynamics during SARS-CoV-2 associated acute respiratory distress syndrome (ARDS). We identified TF motifs that track the severity of COVID- 19 lung injury, disease resolution, and outcome. We used unbiased clustering to reveal distinct cistrome subsets delineating the regulation of pathways, cell types, and the combinatorial activity of TFs. We found critical roles for regulatory networks driven by stimulus and lineage determining TFs, showing that STAT and E2F/MYB regulatory programs targeting myeloid cells are activated in patients with poor disease outcomes and associated with single nucleotide genetic variants implicated in COVID-19 susceptibility. Integration with single-cell RNA-seq found that STAT and E2F/MYB activation converged in specific neutrophils subset found in patients with severe disease. Collectively we demonstrate that cistrome analysis facilitates insight into disease mechanisms and provides an unbiased approach to evaluate global changes in transcription factor activity and stratify patient disease severity.

genomics↗

bioRxiv2021

Gene regulatory networks underlying human microglia maturation

The fetal period is a critical time for brain development, characterized by neurogenesis, neural migration, and synaptogenesis1-3. Microglia, the tissue resident macrophages of the brain, are observed as early as the fourth week of gestation4 and are thought to engage in a variety of processes essential for brain development and homeostasis5-11. Conversely, microglia phenotypes are highly regulated by the brain environment12-14. Mechanisms by which human brain development influences the maturation of microglia and microglia potential contribution to neurodevelopmental disorders remain poorly understood. Here, we performed transcriptomic analysis of human fetal and postnatal microglia and corresponding cortical tissue to define age-specific brain environmental factors that may drive microglia phenotypes. Comparative analysis of open chromatin profiles using bulk and single-cell methods in conjunction with a new computational approach that integrates epigenomic and single-cell RNA-seq data allowed decoding of cellular heterogeneity with inference of subtype- and development stage-specific transcriptional regulators. Interrogation of in vivo and in vitro iPSC-derived microglia models provides evidence for roles of putative instructive signals and downstream gene regulatory networks which establish human-specific fetal and postnatal microglia gene expression programs and potentially contribute to neurodevelopmental disorders.

genomics↗