Biology subjects

Dixit, N.

Publications and source records attributed to Dixit, N..

4 recordsLinked to original sources

bioRxiv2026

Placental derived Extracellular Matrix Supports multi-lineage cell attachment and nuclear remodeling revealed by quantitative imaging

Decellularized extracellular matrix (dECM) scaffolds are increasingly used in regenerative medicine, yet the extent to which processed placental dECM retains properties capable of influencing cellular responses remains unclear. This study combines functional cell assays with deep learning-enabled quantitative imaging to determine how dehydrated placental ECM regulates cellular behavior across multiple human cell lineages. Human dermal fibroblasts, cardiac fibroblasts, and osteoblasts were cultured on dehydrated placental ECM or standard cell culture surfaces and assessed for cell attachment, viability, extracellular matrix production, and nuclear morphology. Placental dECM supported attachment and survival across all three cell types, while Pro-Collagen I Alpha 1 secretion varied by cell lineage relative to negative controls. To identify structural responses associated with scaffold culture, an automated imaging pipeline combining Cellpose-based nuclear segmentation with nuclear morphometric analysis was used to quantify nuclear area, eccentricity, and circularity. Quantitative profiling of hundreds of nuclei revealed scaffold-dependent remodeling of nuclear morphology that was not apparent by conventional microscopy. Cells cultured on placental dECM exhibited reduced nuclear area and increased nuclear eccentricity, while cardiac fibroblasts and osteoblasts showed alterations in nuclear circularity. These lineage-dependent morphological responses demonstrate that placental dECM provides more than a permissive substrate for cell attachment and is associated with measurable changes in cellular architecture following processing. Together, these findings support the biological relevance of processed placental dECM as a regenerative biomaterial and demonstrate the utility of quantitative single-cell morphometric analysis for detecting cell-material interactions that may not be apparent through qualitative imaging alone, guiding the rational design of regenerative therapies.

cell biology↗

bioRxiv2026

Yellow fever vaccine propagation in primary human hepatocytes triggers antiviral and cytolytic responses

Yellow fever virus (YFV) infection can cause severe-to-fatal liver damage in humans, while immunization with the attenuated 17D vaccine strain has an excellent safety record, priming protective host immunity in the absence of pathology. To investigate virus-host correlates associated with these differential clinical outcomes, we combined YFV genome-level evolutionary analyses with investigations of vaccine and virulent strain hepatotropism. Evolutionary analyses confirmed purifying selection is the dominant force driving global YFV genome divergence, with functional constraints associated with the YFV transmission cycle selecting against vaccine attenuating mutations in virulent strains. In immune deficient hepatoma cells, 17D exhibited enhanced early propagation, spreading and apoptosis induction when compared to virulent strains. Ex vivo infections performed in primary human hepatocytes (PHH) from multiple donors confirmed robust propagation of both 17D and virulent YFV strains. RNA-sequencing revealed consistent and shared induction of IFNB and IFNL1-4, modulating overlapping gene programs associated with antiviral responses, immunity, chemotaxis and inflammation, cell-death, metabolic reprogramming and protein translation. Subtle differences in virion production kinetics and the magnitude and tempo of PHH transcriptional responses were observed. Antiviral responses to 17D were activated earlier while responses to virulent YFV were delayed but enhanced, mirroring virus propagation kinetics. More broadly, cellular responses to YFV infection are likely dominated by paracrine IFN signalling, with enriched LRP1 expression coupled with impaired IFN production in PHH contributing to YFVs robust hepatotropism. In summary, we demonstrate comparable propagation kinetics and PHH transcriptional responses to vaccine and virulent YFV strains, highlighting impaired hepatotropism is not a correlate of vaccine attenuation. These data imply that unknown barriers restrict liver access and associated organ pathology upon vaccination with 17D.

microbiology↗

bioRxiv2025

Consensus Co-Expression Analysis Identifies A Common Set Of Co-Expressed Genes Associated With Diabetic Peripheral Neuropathy And Chemotherapy-Induced Peripheral Neuropathy

BackgroundDiabetic peripheral neuropathy (DPN) and chemotherapy-induced peripheral neuropathy (CIPN) are major clinical challenges with limited therapeutic options. While these conditions arise from different causes, they may share common molecular mechanisms that could be targeted for intervention. MethodsWe performed consensus weighted gene co-expression network analysis (WGCNA) on two publicly available datasets: GSE185011 (DPN vs. healthy controls in peripheral blood mononuclear cells) and GSE173610 (paclitaxel-treated vs. control iPSC-derived sensory neurons). After filtering all but the most variable genes, consensus analysis was used to identify conserved co-expression modules across both conditions. ResultsConsensus analysis identified a 193-gene module (ME3/brown) significantly associated with both DPN (correlation=0.817, p=0.0040) and CIPN (correlation=0.971, p=0.0060). Functional enrichment analysis of this module revealed pathways related to Glycolysis, FoxO signaling, Apoptosis, and Autophagy. ConclusionsOur analysis reveals a convergent molecular signature underlying both DPN and CIPN, centered on metabolic reprogramming, transcriptional stress, and programmed cell death. These findings provide a systems-level framework for developing therapies targeting shared pathological mechanisms.

systems biology↗

bioRxiv2023

Myrmecophytism as a driver of macroevolutionary patterns: perspectives from the Southeast Asian Macaranga ant-plant symbiosis

Myrmecophytes utilise defensive services offered by obligate ant partners in a novel means of survival in tropical habitats. Although much is known about the ecology of myrmecophytism, there arent enough empirical examples to demonstrate whether it substantially influences evolutionary patterns in host plant lineages. In this study, we make use of the species-rich Macaranga (Euphorbiaceae) ant-plant symbiosis distributed in Sundaland to delve into the evolutionary dynamics of myrmecophytism in host plants. We generated the most comprehensive dated phylogeny of myrmecophytic Macaranga till date using sequences derived from genotyping-by-sequencing (GBS), a next-generation sequencing (NGS) technique. With this in hand, we traced the evolutionary history of myrmecophytism in Macaranga using parametric biogeography and ancestral state reconstruction. Diversification rate analysis methods were employed to determine if myrmecophytism enhanced diversification rates in the genus. Our results demonstrate that myrmecophytism is plastic and easily lost unless it is overly specialised. Ancestral state reconstruction supported a single origin of myrmecophytism in Macaranga [~]18 mya on Borneo followed by multiple losses. Diversification rate analysis methods did not yield sufficient evidence to support the hypothesis that myrmecophytism enhanced diversification rates in Macaranga; we found that topographical features on Borneo may have played a more direct role in the divergence of clades instead. Through this comprehensive investigation of the evolution of myrmecophytism in Macaranga, our study also provides evidence that a key innovation may not necessarily enhance diversification rates. In fact, we hypothesise that overly specialised cases of myrmecophytism may even be an evolutionary dead end.

evolutionary biology↗