Biology subjects

Raymond, K.

Publications and source records attributed to Raymond, K..

5 recordsLinked to original sources

bioRxiv2025

A multi-institutional investigation of psilocybin's effects on mouse behavior

Studies reporting novel therapeutic effects of psychedelic drugs are rapidly emerging. However, the reproducibility and reliability of these findings could remain uncertain for years. Here, we implemented a multi-institutional collaborative approach to define the robust and replicable effects of the psychedelic drug psilocybin on mouse behavior. Five laboratories performed the same experiments to test the acute and persistent effects of psilocybin (2 mg/kg, IP) on various behaviors that psychedelics have been proposed to affect, including anxiety-related approach-avoidance, exploration, sociability, depression-related behaviors, fear extinction, and social reward learning. Through this coordinated approach, we found that psilocybin had several robust and replicable acute effects on mouse behavior, including increased anxiety- and avoidance-related behaviors and decreased fear expression. Surprisingly, however, we found that psilocybin did not have replicable effects 24 hours post psilocybin administration on reducing anxiety- and depression-like behaviors or facilitating fear extinction learning. Additionally, we were unable to observe psilocybin-induced alterations in social preference or social reward learning. Overall, our comprehensive characterization of psilocybins acute and persistent behavioral effects using [~]200 total male and female mice per experiment spread across five independent labs demonstrates with unique certainty several acute drug effects and suggests that psilocybins persistent effects in mice may be more modest and inconsistent than previously suggested. We believe this unusual multi-laboratory, highly coordinated research effort serves as a model for facilitating the generation of replicable results and consequently will reduce efforts based on unreliable and spurious results.

neuroscience↗

bioRxiv2025

A simplified co-culture reveals altered cardiotoxic responses to doxorubicin in hPSC-derived cardiomyocytes in the presence of endothelial cells

Cardiotoxicity is a significant challenge in cancer therapies, particularly with doxorubicin, a widely used anthracycline known for its broad anti-cancer spectrum but life-threatening cardiac side effects. There is a critical need for more predictive in vitro models to understand doxorubicin-induced cardiotoxicity and patient-specific drug responses. In this study, we used human pluripotent stem cell (hPSC)-derived cardiomyocytes (hPSC-CMs), cardiac fibroblasts (hPSC-cFBs) and endothelial cells (hPSC-ECs) to investigate the cardiotoxic effects of doxorubicin in two-dimensional mono-and multi-cell type cultures. By mimicking the cumulative dose effect seen in patients through repeated doxorubicin treatments and using a machine learning-based in silico image analysis tool, we could precisely quantify caspase 3/7 activity as an early toxicity marker and identify hPSC-CMs in multi-cell type cultures. This innovative approach allowed continuous monitoring of apoptosis from phase-contrast images, revealing that hPSC-ECs showed higher sensitivity to doxorubicin than isogenic hPSC-CMs or hPSC-cFBs and significantly enhanced cardiomyocyte toxicity in co-culture. In contrast, dermal fibroblasts differentiated from the same hPSC line showed no toxic response under the same treatment regimen. These results challenge the conventional focus on cardiomyocytes as the target of drug-induced cardiac damage. Our findings not only highlight the complex interplay among different cardiac cell types in mediating the toxic effects of doxorubicin, but also demonstrate the potential of AI-enabled tools to advance personalized drug screening and safety assessments.

pharmacology and toxicology↗

bioRxiv2024

High-resolution Inference of Multiplexed Anti-HIV Gene Editing using Single-Cell Targeted DNA Sequencing

Gene therapy-based HIV cure strategies typically aim to excise the HIV provirus directly, or target host dependency factors (HDFs) that support viral persistence. Cure approaches will likely require simultaneous co-targeting of multiple sites within the HIV genome to prevent evolution of resistance, and/or co-targeting of multiple HDFs to fully render host cells refractory to HIV infection. Bulk cell-based methods do not enable inference of co-editing within individual viral or target cell genomes, and do not discriminate between monoallelic and biallelic gene disruption. Here, we describe a targeted single-cell DNA sequencing (scDNA-seq) platform characterizing the near full-length HIV genome and 50 established HDF genes, designed to evaluate anti-HIV gene therapy strategies. We implemented the platform to investigate the capacity of multiplexed CRISPR-Cas9 ribonucleoprotein complexes (Cas9-RNPs) to simultaneously 1) inactivate the HIV provirus, and 2) knockout the CCR5 and CXCR4 HDF (entry co-receptor) genes in microglia and primary monocyte-derived macrophages (MDMs). Our scDNA-seq pipeline revealed that antiviral gene editing is rarely observed at multiple loci (or both alleles of a locus) within an individual cell, and editing probabilities across sites are linked. Our results demonstrate that single-cell sequencing is critical to evaluate the true efficacy and therapeutic potential of HIV gene therapy.

genomics↗

bioRxiv2022

CCR4-NOT subunit CCF-1/CNOT7 interacts with the PAL-1/CDX-1 transcription factor to regulate multiple stress responses in Caenorhabditis elegans

CCR4-NOT is a versatile eukaryotic protein complex that controls multiple steps in gene expression regulation from synthesis to decay. In yeast, CCR4-NOT has been implicated in stress response regulation, though this function in other organisms remains unclear. In a genome-wide RNAi screen, we identified a subunit of the CCR4-NOT complex, ccf-1, as a requirement for the C. elegans transcriptional response to cadmium and acrylamide stress. Using whole-transcriptome RNA sequencing, we show that knockdown of ccf-1 attenuates the activation of a broad range of stress protective genes in response to cadmium and acrylamide, including those encoding heat shock proteins and glutathione s-transferases. Consistently, survival assays show that knockdown of ccf-1 decreases C. elegans stress resistance. A yeast-2-hybrid screen using a CCF-1 bait identified the homeobox transcription factor PAL-1 as a physical interactor. Knockdown of pal-1 inhibits the activation of ccf-1 dependent stress genes and reduces C. elegans stress resistance. Gene expression analysis reveals that knockdown of pal-1 down-regulates the mRNA levels of elt-2 and elt-3, which serves as the master transcriptional co-regulators of stress response in the C. elegans intestinal and epidermal tissues respectively. These results reveal a new role for CCR4-NOT in stress response regulation with PAL-1 through the transcriptional control of elt-2 and elt-3 in C. elegans.

genetics↗

bioRxiv2020

TCF-1 regulates the stem-like memory potential of HIV-specific CD8+ T cells in elite controllers

Although many HIV cure strategies seek to expand HIV-specific CD8+ T cells to control the virus, all are likely to fail if cellular exhaustion is not prevented. A loss in stem-like memory properties (i.e., the ability to proliferate and generate secondary effector cells) is a key feature of exhaustion; little is known, however, about how these properties are regulated in human virus-specific CD8+ T cells. We found that virus-specific CD8+ T cells from humans and non-human primates naturally controlling HIV/SIV infection express more of the transcription factor, TCF-1, than non-controllers. HIV-specific CD8+ T cell TCF-1 expression correlated with memory marker expression and proliferative capacity and declined with antigenic stimulation. CRISPR-Cas9 editing of TCF-1 in human primary T cells demonstrated a direct role in regulating expansion capacity. Collectively, these data suggest that TCF-1 controls the stem-like memory properties of HIV-specific CD8+ T cells and provides a rationale for enhancing this pathway in T cell-based therapeutic strategies for HIV. One Sentence SummaryTCF-1 is highly expressed in HIV-specific CD8+ T cells from elite controllers and directly regulates human CD8+ T cell expansion capacity in response to T cell receptor stimulation.

immunology↗