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Biology subjects

Poysungnoen, K.

Publications and source records attributed to Poysungnoen, K..

2 recordsLinked to original sources

Foundation cell segmentation models performance on live microscopy and spatial-omics data

Accurate cell segmentation is an essential step for quantitative analysis of biological imaging data. Recent advances in deep learning have led to the development of generalist segmentation models that perform robustly across multiple imaging modalities, including label-free phase contrast, fluorescence cell culture, and multiplexed fluorescence tissue imaging. However, systematic comparisons of these models at the level of downstream biological analysis remain limited. To address this gap, we evaluated several recent segmentation models, including Cellpose cyto3, Cellpose-SAM, {micro}SAM, and CellSAM, on phase contrast and fluorescence cell culture images. In addition, Mesmer and InstanSeg were included for benchmarking on multiplexed fluorescence tissue images generated using CO-Detection by IndEXing (CODEX). We found that Cellpose-SAM achieved strong performance on phase contrast images, while SAM-based models consistently performed well on fluorescence cell culture data. In contrast, no single model consistently outperformed others on CODEX datasets. Instead, each model exhibited distinct strengths and limitations, which led to differences in downstream analyses, including clustering and cell type identification. Together, our study emphasizes the importance of selecting segmentation models based on dataset characteristics and analytical goals, rather than relying on a single universal approach.

bioinformatics↗

Polysialic Acid Presentation on Microporous Scaffolds Supports Neural Repair after Ischemic Stroke

Recovery following ischemic stroke remains limited due to insufficient neural regeneration. Polysialic acid (PSA), a glycan prominently expressed during neural development, modulates neural progenitor cell (NPC) plasticity and migration, but its therapeutic potential in biomaterial-based stroke therapies remains underexplored. In this study, microporous annealed particle (MAP) scaffolds conjugated with PSA (PSA-MAP) were engineered to regulate NPC fate and promote neural tissue regeneration after stroke. PSA-MAP increased the presence of Sox2-positive progenitor cells within infarct and peri-infarct regions and elevated axonal content (NF200) in the lesion, while astrocytic and vascular coverage were not detectably changed at this early stage. In addition, 3D NPC cultures in MAP showed that tethered PSA alters NPC behavior over time, with reduced progenitor marker expression and PSA-dependent shifts in morphology, consistent with progression away from a progenitor state. Together, these data identify a glycan-forward, neuro-first repair route in which PSA-MAP enhances early neural regeneration without requiring concomitant angiogenic expansion, establishing PSA-MAP as a targeted biomaterial approach for endogenous neural repair after ischemic stroke.

bioengineering↗