Biology subjects

Murugappan, S.

Publications and source records attributed to Murugappan, S..

3 recordsLinked to original sources

bioRxiv2025

A Deep Learning Pipeline for Morphological and Viability Assessment of 3D Cancer Cell Spheroids

Three-dimensional (3D) spheroid models have advanced cancer research by better mimicking the tumour microenvironment compared to traditional 2D dimensional (2D) cell cultures. However, challenges persist in high-throughput analysis of morphological characteristics and cell viability, as traditional methods like manual fluorescence analysis are labour-intensive and inconsistent. Existing AI-based approaches often address segmentation or classification in isolation, lacking an integrated workflow. We propose a scalable, two-stage deep learning pipeline to address these gaps: (1) a U-Net model for precise detection and segmentation of 3D spheroids from microscopic images, achieving 95% prediction accuracy, and (2) a CNN Regression Hybrid method for estimating live/dead cell percentages and classifying spheroids, with an R2value of 98%. This end-to-end pipeline automates cell viability quantification and generates key morphological parameters for spheroid growth kinetics. By integrating segmentation and analysis, our method addresses environmental variability and morphological characterization challenges, offering a robust tool for drug discovery, toxicity screening, and clinical research. This approach significantly improves efficiency and scalability of 3D spheroid evaluations, paving the way for advancements in cancer therapeutics.

cancer biology↗

bioRxiv2024

Astrocyte-Neuron co-cultured 3D tumor spheroid model for Anti-cancer Drug Screening

Glioblastoma is the most lethal primary brain tumor, and its resistance to therapy is increasingly understood to arise not from tumor cells alone but also from their integration into the surrounding neural circuitry. However, no existing preclinical spheroid model isolates the direct effect of neuronal cells on glioblastoma's drug response within a rapid, scalable 3D system. We developed a heterotypic 3D co-culture spheroid combining glioblastoma (U87-MG) with a neuronal lineage population (SH-SY5Y) via the agarose liquid overlay method to directly understand this gap. Subsequently, growth, morphology, hypoxia, and temozolomide (TMZ) response over 14 days against glioblastoma only and neuroblastoma only spheroids were characterized. The co-culture adopted a glioblastoma like compact, chemoresistant architecture yet, contrary to what this architecture alone would predict, it showed measurable chemosensitivity at every TMZ concentration tested, including 10M, a dose at which neither monoculture responded at all. This reveals that the neuronal lineage component actively sensitizes glioblastoma to chemotherapy independent of spheroid architecture. Drug-response data from glioblastoma only models may therefore not reflect true tumor behavior within its native neuronal environment, underscoring the need for neuron inclusive platforms in preclinical glioblastoma drug screening.

cancer biology↗

bioRxiv2021

Circuit-specific sonogenetic stimulation of the deep brain elicits distinct signaling and behaviors in freely moving mice

Sonogenetics uses heterologously-expressed proteins to sensitize neurons to ultrasound, enabling selective, non-invasive, and deep brain stimulation. However, its ability to modulate specific circuits or induce behavioral changes remains to be studied and characterized. Here, we demonstrate that sonogenetics enables efficient activation of well-defined neural circuits by transcranial low-intensity, low-frequency ultrasonic stimulation with high spatiotemporal resolution. Targeted neurons in subcortical regions were made to express a mechanosensitive ion channel (MscL-G22S). Ultrasound could trigger activity in MscL-expressing neurons in the dorsal striatum without increased activation in neighboring regions, and increase locomotion in freely-moving mice. Ultrasound stimulation of MscL-expressing neurons in the ventral tegmental area could activate the mesolimbic pathway to trigger dopamine release in the nucleus accumbens and modulate appetitive conditioning. In MscL-expressing cells, neuronal responses to ultrasound pulses were rapid, reversible and repeatable. Altogether, we show that sonogenetics can selectively manipulate targeted cells to activate defined neural pathways and affect behaviors.

neuroscience↗