Biology subjects

Foyt, D.

Publications and source records attributed to Foyt, D..

4 recordsLinked to original sources

bioRxiv2025

RainBar: Optical Barcoding for Pooled Live-Cell Imaging with Single-Cell Resolution

High-throughput pooled screening has advanced functional genomics, but most existing methods rely on endpoint sequencing and are blind to dynamic, time-resolved phenotypes. We developed RainBar (Rainbow Barcodes), an optical barcoding system that supports pooled live-cell imaging with single-cell resolution. RainBar uses lentiviral co-delivery of spectrally distinct nuclear and cytoplasmic fluorescent proteins to encode up to 64 unique perturbations per well. To mitigate barcode recombination and improve decoding accuracy, we employed single-template viral production, codon diversification, and a ratio-based spectral unmixing pipeline tailored to overlapping fluorophores. An inverted cytoplasmic segmentation approach and multilayer perceptron classifier enabled accurate barcode identification in both arrayed and pooled formats. As a proof of concept, we applied RainBar to dissect NF-{kappa}B signaling dynamics in epithelial cells. Live imaging of RelA translocation uncovered stimulus-specific kinetics: IL-1{beta} triggered rapid recovery, while TNF induced prolonged nuclear localization. In pooled CRISPRi screens, RainBar recovered known NF-{kappa}B regulators (e.g., IL1R1, MYD88, TNFRSF1A) and highlighted additional modulators, including the Ino80 chromatin remodeling complex subunits and KAT2A acetyltransferase. Together, these results position RainBar as a flexible platform for multiplexed, image-based functional genomics, with potential to reveal dynamic signaling architectures across diverse cellular contexts in live cells.

genomics↗

bioRxiv2025

Accessible and accurate cytometry analysis using fluorescence microscopes

We have developed a method along with a python-based analysis tool to capture images and produce flow cytometry like data utilizing simple accessible microscopes. Utilizing the recently developed generalist algorithms for cell segmentation, our approach easily segments semi-adherent or suspended cells facilitating quantification of fluorescent intensity similar to flow cytometry. We have shown that our approach exhibits similar speed and enhanced sensitivity when compared to typical flow cytometry. The utility of our approach is demonstrated by screening a set of 88 prime editing conditions utilizing the integration of mNeonGreen11 as a reporter.

cell biology↗

bioRxiv2023

HybriSeq: Probe-based Device-free Single-cell RNA Profiling

We have developed the HybriSeq method for single-cell RNA profiling, which utilizes in situ hybridization of multiple probes for targeted transcripts, followed by split-pool barcoding and sequencing analysis of the probes. We have shown that HybriSeq can achieve high sensitivity for RNA detection with multiple probes and profile entire transcripts without an end bias. The utility of HybriSeq is demonstrated in characterizing cell-to-cell heterogeneities of a panel of 196 genes in peripheral blood mononuclear cells and the detection of missed annotations of transcripts.

bioengineering↗

bioRxiv2020

Senotherapeutic peptide reduces skin biological age and improves skin health

Skin aging has been primarily related to aesthetics and beauty. Therefore, interventions have focused on reestablishing skin appearance, but not necessarily skin health, function, and resilience. Recently, cellular senescence was shown to play a role in age-related skin function deterioration and influence organismal health and, potentially, longevity. In the present study, a two-step screening was performed to identify peptides capable of reducing cellular senescence in human dermal fibroblasts (HDF) from Hutchinson-Gilford Progeria (HGPS) patients. From the top four peptides of the first round of screening, we built a 764-peptide library using amino acid scanning, of which the second screen led to the identification of peptide 14. Peptide 14 effectively decreased HDF senescence induced by HGPS, chronological aging, ultraviolet-B radiation, and etoposide treatment, without inducing significant cell death, and likely by modulating longevity and senescence pathways. We further validated the effectiveness of peptide 14 using human skin equivalents and skin biopsies, where peptide 14 promoted skin health and reduced senescent cell markers, as well as the biological age of samples, according to the Skin-Specific DNA methylation clock, MolClock. Topical application of peptide 14 outperformed Retinol treatment, the current gold-standard in "anti-aging" skin care. Finally, we determined that peptide 14 is safe for long-term applications and also significantly extends both the lifespan and healthspan of C. elegans worms tested in two independent testings. This highlights the potential for geroprotective applications of the senotherapeutic compounds identified using our screening platform beyond the skin.

bioengineering↗