Biology subjects

Krizic, K.

Publications and source records attributed to Krizic, K..

4 recordsLinked to original sources

bioRxiv2026

multiomeR: a pipeline for reproducible analysis of large-scale single-nucleus Epi Multiome datasets

The 10x Genomics Epi Multiome assay measures gene expression and chromatin accessibility in the same nuclei, and studies increasingly profile many samples. Yet analysis after Cell Ranger ARC is usually assembled by hand from separate tools, which makes it slow to revise, hard to reproduce and memory-intensive for large studies. multiomeR addresses these problems with a configurable R pipeline for quality control, processing and integration of both data types, and cell-type annotation across many samples. Plain-text configuration files record every analytical choice, each step is tracked so that a change reruns only what it affects, and data stay on disk rather than in memory. Optional modules compare groups of donors, link accessible regions to the genes they may regulate, and test which cell types are enriched for genetic associations with a trait. In a benchmark on 31 public samples (375,757 nuclei), multiomeR had a shorter estimated run time than a Seurat v5.6/Signac v2 workflow (2.2 versus 5.6 h), because it runs independent steps in parallel. It also used fewer memory gigabyte-hours (87 versus 114 GB-hours), with similar total CPU time. multiomeR thus makes large multi-sample multiome studies practical to analyze, revise and extend.

bioinformatics↗

bioRxiv2024

Design principles of small intestinal crypt maintenance

The intestinal epithelium has a remarkably high turnover in homeostasis. It remains unresolved how turnover is orchestrated at the cellular level and how the behaviour of stem and progenitor cells ensures tissue maintenance. To address this, we combined quantitative fate mapping in three complementary mouse models with mathematical modelling and single-cell RNA sequencing. Our integrated approach generated a spatially and temporally defined model of crypt maintenance that is based on two cycling populations: crypt-based columnar (CBC) and transit amplifying (TA) cells. Validation experiments substantiated the predictions from the model revealing TA cells as the major contributor to the absorptive lineage, while balanced CBC cell fate choices controlled the numbers of cells in the secretory lineage. By unravelling these mechanisms, we gain insights into the process of tissue turnover and provide direct evidence to support the notion of CBC cells as the major driver of the intestinal epithelium replenishment. HighlightsO_LISpatially and temporally resolved cellular model of small intestinal crypt maintenance. C_LIO_LIStem cells exhibit predisposition towards secretory fate. C_LIO_LISecretory lineage has a limited contribution to the high turnover of intestinal epithelium. C_LIO_LICellular differentiation within the crypt occurs rapidly within 72 hours. C_LI

cell biology↗

bioRxiv2024

JAK/STAT signaling promotes the emergence of unique cell states in ulcerative colitis

The intestinal epithelium forms a barrier to the lumen and ensures uptake of vital nutrients. During inflammatory diseases, such as ulcerative colitis (UC), this barrier is compromised. Here, we perform single-cell RNA sequencing (scRNA-seq) of epithelial cells and outline patterns of cell fate decisions in healthy individuals and patients with UC. We demonstrate that lineage biased progenitors are major sources of normal tissue replenishment, and that patterns of cell behavior are profoundly altered in UC. We furthermore identify unique regenerative cell states linked to JAK/STAT activation extending into the non-inflamed areas of the colon. In organoid models, this can be mimicked by cytokine mediated activation of JAK/STAT leading to the emergence of cell populations with regenerative potential. These findings have profound implications for our understanding of tissue regeneration and illustrates how cytokine signaling influences cell fate decisions. This suggests widespread consequences in patients with chronic ulcerative conditions.

cell biology↗

bioRxiv2021

A biomechanical switch regulates the transition towards homeostasis in esophageal epithelium

Epithelial cells are highly dynamic and can rapidly adapt their behavior in response to tissue perturbations and increasing tissue demands. However, the processes that finely control these responses and, particularly, the mechanisms that ensure the correct switch to and from normal tissue homeostasis are largely unknown. Here we explore changes in cell behavior happening at the interface between postnatal development and homeostasis in the epithelium of the mouse esophagus, as a physiological model exemplifying a rapid but controlled tissue growth transition. Single cell RNA sequencing and histological analysis of the mouse esophagus reveal significant mechanical changes in the epithelium upon tissue maturation. Organ stretching experiments further indicate that tissue strain caused by the differential growth of the mouse esophagus relative to the entire body promotes the emergence of a defined committed population in the progenitor compartment as homeostasis is established. Our results point to a simple mechanism whereby the mechanical changes experienced at the whole tissue level are integrated with those "sensed" at the cellular level to control epithelial cell behavior and tissue maintenance.

cell biology↗