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Results for “cell biology”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

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At least 325 records · Page 18Linked to original sources

bioRxiv2025

Transfection of the free-living alga Chromera velia enables direct comparisons with its parasitic apicomplexan relative, Toxoplasma gondii

Chromera velia is a photosynthetic, free-living alga that is closely related to the apicomplexans, a phylum of intracellular parasites responsible for many devastating diseases, including malaria, cryptosporidiosis, and toxoplasmosis. With molecular and cellular landmarks that are clearly related to but distinguishable from those found in apicomplexan parasites, Chromera provides a fantastic opportunity to investigate the evolutionary origin of the structures and processes needed for intracellular parasitism. However, tools for defining localization and functions of gene products do not exist for Chromera, which creates a major bottleneck for exploring its biology. Here we report two major advances in exploring the cell biology of this free-living relative of a large group of intracellular parasites: 1) successful cell transformation and 2) the implementation of expansion microscopy. The initial analysis enabled by these tools generated new insights into subcellular organization in different life stages of Chromera. These new developments boost the potential of Chromera as a model system for understanding the evolution of parasitism in apicomplexans.

cell biology↗

bioRxiv2021

Pacemaking function of two simplified cell models

Simplified nonlinear models of biological cells are widely used in computational electrophysiology. The models reproduce qualitatively many of the characteristics of various organs, such as the heart, brain, and intestine. In contrast to complex cellular ion-channel models, the simplified models usually contain a small number of variables and parameters, which facilitates nonlinear analysis and reduces computational load. In this paper, we consider pacemaking variants of the Aliev-Panfilov and Corrado two-variable excitable cell models. We conducted a numerical simulation study of these models and investigated the main nonlinear dynamic features of both isolated cells and 1D coupled pacemaker-excitable systems. Simulations of the 2D sinoatrial node and 3D intestine tissue as application examples of combined pacemaker-excitable systems demonstrated results similar to obtained previously. The uniform formulation for the conventional excitable cell models and proposed pacemaker models allows a convenient and easy implementation for the construction of personalized physiological models, inverse tissue modeling, and development of real-time simulation systems for various organs that contain both pacemaker and excitable cells.

biophysics↗

bioRxiv2020

ERK basal and pulsatile activity are differentially regulated in mammalian epidermis to control proliferation and exit from the stem cell compartment

Fluctuation in signal transduction pathways is frequently observed during mammalian development. However, its role in regulating stem cells has not been explored. Here we tracked spatiotemporal ERK MAPK dynamics in human epidermal stem cells. While stem cells and differentiated cells were distinguished by high and low stable basal ERK activity, respectively, we also found cells with pulsatile ERK activity. Transitions from Basalhi-Pulselo (stem) to Basalhi-Pulsehi, Basalmid-Pulsehi, and Basallo-Pulselo (differentiated) cells occurred in expanding keratinocyte colonies and in response to a range of differentiation stimuli. Pharmacological inhibition of ERK induced differentiation only when cells were in the Basalmid-Pulsehi state. Basal ERK activity and pulses were differentially regulated by DUSP10 and DUSP6, leading us to speculate that DUSP6-mediated ERK pulse downregulation promotes initiation of differentiation whereas DUSP10-mediated downregulation of mean ERK activity promotes and stabilizes post-commitment differentiation. Quantification of MAPK1/3, DUSP6 and DUSP10 transcripts in individual cells demonstrated that ERK activity is controlled both transcriptionally and post-transcriptionally. When cells were cultured on a topography that mimics the epidermal-dermal interface, spatial segregation of mean ERK activity and pulses was observed. In vivo imaging of mouse epidermis revealed a patterned distribution of basal cells with pulsatile ERK activity and downregulation was linked to the onset of differentiation. Our findings demonstrate that ERK MAPK signal fluctuations link kinase activity to stem cell dynamics. SignificanceUnderstanding how intracellular signaling cascades control cell fate is a key issue in stem cell biology. Here we show that exit from the stem cell compartment in mammalian epidermis is characterised by pulsatile ERK MAPK activity. Basal activity and pulses are differentially regulated by DUSP10 and DUSP6, two phosphatases that have been shown previously to regulate differentiation commitment in the epidermis. ERK activity is controlled both transcriptionally and post-transcriptionally. Spatial segregation of mean ERK activity and pulses is observed both in reconstituted human epidermis and in mouse epidermis. Our findings demonstrate the tight spatial and temporal regulation of ERK MAPK expression and activity in mammalian epidermis.

cell biology↗

bioRxiv2020

Melanocyte differentiation and epidermal pigmentation is regulated by polarity proteins

Pigmentation serves various purposes such as protection, camouflage, or attraction. In the skin epidermis, melanocytes react to certain environmental signals with melanin production and release, thereby ensuring photo-protection. For this, melanocytes acquire a highly polarized and dendritic architecture that facilitates interactions with surrounding keratinocytes and melanin transfer. How the morphology and function of these neural crest-derived cells is regulated remains poorly understood. Here, using mouse genetics and primary cell cultures, we show that conserved proteins of the mammalian Par3-aPKC polarity complex are required for epidermal pigmentation. Melanocyte-specific deletion of Par3 in mice caused skin hypopigmentation, reduced expression of components of the melanin synthesis pathway, and altered dendritic morphology. Mechanistically, Par3 was necessary downstream of -melanocyte stimulating hormone (-MSH) to elicit melanin production. Strikingly, pharmacologic activation of MITF using a salt-inducible kinase inhibitor was sufficient to restore melanocyte differentiation and skin pigmentation in the absence of Par3. This data reveals a central role of polarity proteins in transmitting external pigment-inducing signals through the -MSH/Mc1R/MITF tanning pathway, exposing unexpected links between polarity signaling and melanogenesis with new insights for pigment cell biology.

cell biology↗

bioRxiv2021

Impact of isolation method on cellular activation and presence of specific tendon cell subpopulations during in vitro culture

Tendon injuries are common and heal poorly, due in part to a lack of understanding of fundamental tendon cell biology. A major impediment to the study of tendon cells is the absence of robust, well-characterized in vitro models. Unlike other tissue systems, current tendon cell models do not account for how differences in isolation methodology may affect the activation state of tendon cells or the presence of various tendon cell sub-populations. The objective of this study was to characterize how common isolation methods affect the behavior, fate, and lineage composition of tendon cell cultures. Tendon cells isolated by explant exhibited reduced proliferative capacity, decreased expression of tendon marker genes, and increased expression of genes associated with fibroblast activation compared to digested cells. Consistently, explanted cells also displayed an increased propensity to differentiate to myofibroblasts compared to digested cells. Explanted cultures from multiple different tendons were substantially enriched for the presence of scleraxis-lineage (Scx-lin+) cells compared to digested cultures, while the overall percentage of S100a4-lineage (S100a4-lin+) cells was dependent on both isolation method and tendon of origin. Neither isolation method preserved the ratios of Scx-lin+ or S100a4-lin+ to non-lineage cells seen in tendons in vivo. Combined, these data indicate that further refinement of in vitro cultures models is required in order to more accurately understand the effects of various stimuli on tendon cell behavior. Statement of clinical significanceThe development of informed in vitro tendon cell models will facilitate enhanced screening of potential therapeutic candidates to improve tendon healing.

cell biology↗

bioRxiv2021

The HIV-1 capsid core is an opportunistic nuclear import receptor

The movement of viruses and other large macromolecular cargo through nuclear pore complexes (NPCs) is poorly understood. The human immunodeficiency virus type 1 (HIV-1) provides an attractive model to interrogate this process due to the genetic and cell biological assays to score virus nuclear entry in living cells. Although initial studies of HIV-1 infection of nondividing cells focused on karyophilic virion proteins, subsequent work revealed the viral capsid (CA), the chief structural component of the pre-integration complex (PIC), to be a critical determinant in nuclear transport1. In support of this model, HIV-1 interactions with NPCs can be altered through CA mutation2, which makes direct contact with nucleoporins (Nups)3-5. Here we identify Nup35, Nup153, and POM121 to coordinately support HIV-1 nuclear entry. For Nup35 and POM121, this dependence was strongly dependent cyclophilin A (CypA) interaction with CA. Mutation of CA or removal of soluble host factors changed the interaction with the NPC. Collectively, these findings implicate the HIV-1 CA hexameric lattice that encapsulates the viral genome as a macromolecular nuclear transport receptor (NTR) that exploits soluble host factors to modulate NPC requirements during nuclear invasion.

cell biology↗

bioRxiv2023

Electron microscopic analysis of the influence of iPSC-derived motor neurons on bioengineered human skeletal muscle tissues

3D bioengineered skeletal muscle macrotissues are increasingly important for studies of cell biology and development of therapeutics. Tissues derived from immortalized cells obtained from patient samples or from stem cells can be co-cultured with motor-neurons to create models of human neuromuscular junctions in culture. In this study, we present foundational work on 3D cultured muscle ultrastructure, with and without motor neurons, which is enabled by the development of a new co-culture platform. Our results show that tissues from Duchenne muscular dystrophy patients are poorly organized compared to tissues grown from healthy donor and that the presence of motor neurons invariably improves sarcomere organization. Electron micrographs show that in the presence of motor neurons, filament directionality, banding patterns, z-disc continuity and appearance of presumptive SSR and T-tubule profiles all improve in healthy, DMD and iPSC derived muscle tissue. Further work to identify the underlying defects of DMD tissue disorganization and the trophic mechanisms by which motor neurons support muscle are likely to yield potential new therapeutic approaches for treating patients suffering from Duchenne muscular dystrophy.

cell biology↗

bioRxiv2024

A novel human pluripotent stem cell-based gene activation system identifies IGFBP2 as a mediator in the production of hematopoietic progenitors in vitro

A major challenge in the stem cell biology field is the ability to produce fully functional cells from induced pluripotent stem cells (iPSCs) that are a valuable resource for cell therapy, drug screening and disease modelling. Here we developed a novel inducible CRISPR-mediated activation strategy (iCRISPRa) to drive the expression of multiple endogenous transcription factors important for in vitro cell fate and differentiation of iPSCs to haematopoietic progenitor cells. This work has identified a key role for IGFBP2 in the development of hematopoietic progenitors. We first identified nine candidate transcription factors that we predicted to be involved in blood cell emergence during development, then generated tagged gRNAs directed to the transcriptional start site of these transcription factors that could also be detected during scRNAseq. iCRISPRa activation of these endogenous transcription factors resulted in a significant expansion of arterial-fated endothelial cells expressing high levels of IGFBP2 and our analysis indicated that IGFBP2 is involved in the remodeling of metabolic activity during in vitro endothelial to hematopoietic transition. As well as providing fundamental new insights into the mechanisms of haematopoietic cell fate and differentiation, the broader applicability of iCRISPRa provides a valuable tool for studying dynamic processes controlling developmental events and for recapitulating abnormal phenotypes characterised by ectopic activation of specific endogenous gene expression in a wide range of systems.

cell biology↗

bioRxiv2026

Somatic cells non-autonomously control germline incomplete cytokinesis through FGF signaling

Across species, germ cells divide and differentiate as interconnected units, termed cysts. These cysts are generated through reiterative rounds of mitosis followed by incomplete cytokinesis to generate stable ring canals (RCs). Despite the ubiquity of germ cell incomplete cytokinesis, it is still unclear how this program is mechanistically regulated across multiple cell cycles to retain integrity of the cyst. Here, by leveraging longitudinal live imaging of the Drosophila testis we have identified a critical, non-autonomous role for somatic support cells in maintenance of germline RC stability. We find that F-actin at RCs is stable throughout interphase but is dynamically disassembled and reassembled at each reiterative mitotic entrance and exit. Importantly, we find that somatic cells regulate the stability of interphase RC F-actin through the secreted growth factor, FGF. Genetic or pharmacological inhibition of FGF signaling induces disassembly of RC F-actin during interphase. Persistent clearance of F-actin from the RC leads to failure of incomplete cytokinesis and cyst abscission, suggesting that stable F-actin at RCs is required for the robust maintenance of incomplete cytokinesis through multiple rounds of germ cell divisions. Finally, we mechanistically link FGF signaling to germline activity of the non-receptor tyrosine kinase, Src64, which is known to regulate RC F-actin through Arp2/3. Taken together, we find a previously unappreciated role for somatic support cells in controlling an essential aspect of germ cell biology in the mitotically dividing spermatogonial pool. Summary StatementSomatic cells of the gonad secrete FGF ligand, Pyramus, which is required for maintenance of F-actin at germline ring canals and integrity of germline incomplete cytokinesis.

cell biology↗

bioRxiv2024

scGenePT: Is language all you need for modeling single-cell perturbations?

Modeling single-cell perturbations is a crucial task in the field of single-cell biology. Predicting the effect of up or down gene regulation or drug treatment on the gene expression profile of a cell can open avenues in understanding biological mechanisms and potentially treating disease. Most foundation models for single-cell biology learn from scRNA-seq counts, using experimental data as a modality to generate gene representations. Similarly, the scientific literature holds a plethora of information that can be used in generating gene representations using a different modality - language - as the basis. In this work, we study the effect of using both language and experimental data in modeling genes for perturbation prediction. We show that textual representations of genes provide additive and complementary value to gene representations learned from experimental data alone in predicting perturbation outcomes for single-cell data. We find that textual representations alone are not as powerful as biologically learned gene representations, but can serve as useful prior information. We show that different types of scientific knowledge represented as language induce different types of prior knowledge. For example, in the datasets we study, subcellular location helps the most for predicting the effect of single-gene perturbations, and protein information helps the most for modeling perturbation effects of interactions of combinations of genes. We validate our findings by extending the popular scGPT model, a foundation model trained on scRNA-seq counts, to incorporate language embeddings at the gene level. We start with NCBI gene card and UniProt protein summaries from the genePT approach and add gene function annotations from the Gene Ontology (GO). We name our model "scGenePT", representing the combination of ideas from these two models. Our work sheds light on the value of integrating multiple sources of knowledge in modeling single-cell data, highlighting the effect of language in enhancing biological representations learned from experimental data.

bioinformatics↗

bioRxiv2024

Ultrack: pushing the limits of cell tracking across biological scales

Tracking live cells across 2D, 3D, and multi-channel time-lapse recordings is crucial for understanding tissue-scale biological processes. Despite advancements in imaging technology, achieving accurate cell tracking remains challenging, particularly in complex and crowded tissues where cell segmentation is often ambiguous. We present Ultrack, a versatile and scalable cell-tracking method that tackles this challenge by considering candidate segmentations derived from multiple algorithms and parameter sets. Ultrack employs temporal consistency to select optimal segments, ensuring robust performance even under segmentation uncertainty. We validate our method on diverse datasets, including terabyte-scale developmental time-lapses of zebrafish, fruit fly, and nematode embryos, as well as multi-color and label-free cellular imaging. We show that Ultrack achieves state-of-the-art performance on the Cell Tracking Challenge and demonstrates superior accuracy in tracking densely packed embryonic cells over extended periods. Moreover, we propose an approach to tracking validation via dual-channel sparse labeling that enables high-fidelity ground truth generation, pushing the boundaries of long-term cell tracking assessment. Our method is freely available as a Python package with Fiji and napari plugins and can be deployed in a high-performance computing environment, facilitating widespread adoption by the research community.

developmental biology↗

bioRxiv2026

Single cell Correlation Analysis (SCA): Identifying self-renewing subpopulation of human acute myeloid leukemia stem cells using single cell RNA sequencing analysis

Leukemia stem cells (LSCs), a rare and self-renewing subpopulation, drive Acute myeloid leukemia (AML) relapse and therapy resistance. While single-cell gene expression profiling (scGEP) offers high-resolution insights into LSC biology, existing computational tools rely on relative and arbitrary similarity metrics. This limits their ability to definitively identify true biological cell identities or compare rare cell populations across independent datasets. To overcome these limitations, we developed Single cell Correlation Analysis (SCA), a novel computational method that utilizes a permutation-based false discovery rate (FDR) framework and common background datasets to establish standardized, statistically rigorous thresholds of similarity. We applied SCA to query human AML scRNA-seq datasets using an experimentally validated murine scGEP of LSC self-renewal as our reference. SCA demonstrated superior specificity and precision, maintaining low false positive rates compared to existing reference-based annotation tools. Using SCA, we successfully identified cells expressing a conserved self-renewal program (scaLSC-SR) in both adult and pediatric human AML samples. These scaLSC-SR cells share classical LSC immunophenotypic markers (e.g., CD34, CD96, CD200) and exhibit transcriptomic hallmarks of LSC biology, including evasion of apoptosis and immune responses. Furthermore, this self-renewal program is significantly enriched in poor-risk genetic subtypes, specifically TP53 and NRAS mutated AML. Finally, we derived a 28-gene signature (LSC-SR28) from human AML patients that accurately captures LSC stemness and is highly prognostic across multiple independent clinical cohorts. SCA provides a robust, statistically principled framework for identifying rare and biologically meaningful cell populations across heterogeneous single-cell datasets. By successfully identifying a functional self-renewal profile to human AML, SCA reveals conserved, clinically relevant LSC populations that drive relapse and therapy resistance across different age groups.

cancer biology↗

bioRxiv2021

Defining the transcriptional signature of esophageal-to-skin lineage conversion

The ability of epithelial cells to rewire their cell fate program beyond their physiological repertoire has become a new paradigm in stem cell biology. This plasticity leaves behind the concept of strict stem cell hierarchies, opening up new exciting questions about its limits and underlying regulation. Here we developed a heterotypic 3D culture system to study the mechanisms modulating changes in the identity of adult esophageal epithelial cells. We demonstrate that, when exposed to the foreign stroma of adult skin, esophageal cells transition towards hair follicle identity and architecture. Heterotypic transplantation experiments recapitulated this cell fate conversion process in vivo. Single-cell RNA sequencing and histological analysis, capturing the temporality of this process, reveal that most esophageal cells switching towards skin identity remain in an intermediate state marked by a transient regenerative profile and a particularly strong hypoxic signature. Inhibition of HIF1a establishes the central role of this pathway in regulating epithelial cell plasticity, driving cells away from their transition state in favor of cell fate conversion.

cell biology↗

bioRxiv2021

A method to study extracellular vesicles secreted in vitro by cultured cells with minimum sample processing and extracellular vesicle loss

Extracellular vesicles (EVs) are involved in a multitude of physiological functions and play important roles in health and disease. The study of EV secretion and EV characterization remains challenging due to the small size of these particles, a lack of universal EV markers, and sample loss or technical artifacts that are often associated with EV separation techniques. We developed a method for in-cell EV labeling with fluorescent lipids (DiI), followed by DiI-labelled EV characterization in the conditioned medium by imaging flow cytometry (IFC). Direct IFC analysis of EVs in the conditioned medium, after removal of apoptotic bodies and cellular debris, significantly reduces sample processing and loss compared to established methods for EV separation, resulting in improved detection of quantitative changes in EV secretion and subpopulations compared to protocols that rely on EV separation by ultracentrifugation. In conclusion, our optimized protocol for EV labeling and analysis reduces EV sample processing and loss, and is well suited for cell biology studies that focus on modulation of EV secretion by cells in culture.

cell biology↗

bioRxiv2022

Modeling cell size control using differential scaling of cell-cycle regulators with cell size

Accurate timing of division and size homeostasis is crucial for cells. A potential mechanism for cells to decide the timing of division is the differential scaling of regulatory protein copy numbers with cell size. However, it remains unclear whether such a mechanism can lead to robust growth and division, and how the scaling behaviors of regulatory proteins influence the cell size distribution. Here we study a mathematical model combining gene expression and cell growth, in which the cell-cycle activators scale superlinearly with cell size while the inhibitors scale sublinearly. The cell divides once the ratio of their concentrations reaches a threshold value. We find that the cell can robustly grow and divide within a finite range of the threshold value with the cell size proportional to the ploidy. In a stochastic version of the model, the cell size at division is uncorrelated with that at birth. Also, the more differential the cell-size scaling of the cell-cycle regulators is, the narrower the cell-size distribution is. Intriguingly, our model with multiple regulators rationalizes the observation that after the deletion of a single regulator, the coefficient of variation of cell size remains roughly the same though the average cell size changes significantly. Our work reveals that the differential scaling of cell-cycle regulators provides a robust mechanism of cell size control. Author summaryHow cells determine the timing of cell division is a fundamental question of cell biology. It has been found that the concentration of cell-cycle activators tends to increase with cell size, while the concentration of inhibitors tends to decrease. Therefore, an attractive hypothesis is that the ratio of activators to inhibitors may trigger cell division. To investigate this hypothesis quantitatively, we study a model including gene expression and cell growth simultaneously. The cell divides once the activator-to-inhibitor ratio reaches a threshold. Combining theories and simulations, we analyze the conditions of robust cell cycle and the cell size distribution. Our model successfully rationalizes several experimental observations, including the relation between cell size and ploidy, the sizer behavior of cell size control, and the change of the mean and breadth of cell size distribution after regulator deletion.

cell biology↗

bioRxiv2023

Arp2/3 Complex Activity Enables Nuclear YAP for Naive Pluripotency of Human Embryonic Stem Cells

Our understanding of transitions of human embryonic stem cells between distinct stages of pluripotency relies predominantly on regulation by transcriptional and epigenetic programs with limited insight on the role of established morphological changes. We report remodeling of the actin cytoskeleton of human embryonic stem cells (hESCs) as they transition from primed to naive pluripotency that includes assembly of a ring of contractile actin filaments encapsulating colonies of naive hESCs. Activity of the Arp2/3 complex is required for the actin ring, uniform cell mechanics within naive colonies, nuclear translocation of the Hippo pathway effectors YAP and TAZ, and effective transition to naive pluripotency. RNA-sequencing analysis confirms that Arp2/3 complex activity regulates Hippo signaling in hESCs, and impaired naive pluripotency with inhibited Arp2/3 complex activity is rescued by expressing a constitutively active, nuclear-localized YAP-S127A. These new findings on the cell biology of hESCs reveal a mechanism for cytoskeletal dynamics coordinating cell mechanics to regulate gene expression and facilitate transitions between pluripotency states.

cell biology↗

bioRxiv2023

Atherosclerosis is a smooth muscle cell-driven tumor-like disease

Atherosclerosis, the leading cause of cardiovascular disease, is a chronic inflammatory disease involving pathological activation of multiple cell types, such as immunocytes (e.g., macrophage, T cells), smooth muscle cells (SMCs), and endothelial cells. Multiple lines of evidence have suggested that SMC "phenotypic switching" plays a central role in atherosclerosis development and complications. Yet, SMC roles and mechanisms underlying the disease pathogenesis are poorly understood. Here, employing SMC lineage tracing mice, comprehensive molecular, cellular, histological, and computational profiling, coupled to genetic and pharmacological studies, we reveal that atherosclerosis, in terms of SMC behaviors, share extensive commonalities with tumors. SMC-derived cells in the disease show multiple characteristics of tumor cell biology, including genomic instability, replicative immortality, malignant proliferation, resistance to cell death, invasiveness, and activation of comprehensive cancer-associated gene regulatory networks. SMC-specific expression of oncogenic KrasG12D accelerates SMC phenotypic switching and exacerbates atherosclerosis. Moreover, we present a proof of concept showing that niraparib, an anti-cancer drug targeting DNA damage repair, attenuates atherosclerosis progression and induces regression of lesions in advanced disease in mouse models. Our work provides systematic evidence that atherosclerosis is a tumor-like disease, deepening the understanding of its pathogenesis and opening prospects for novel precision molecular strategies to prevent and treat atherosclerotic cardiovascular disease.

cell biology↗

bioRxiv2025

Preservation of soluble enhanced green fluorescent protein (EGFP) within fixed NIH 3T3 fibroblasts

Quantitative imaging of cytoplasmic green fluorescence protein (GFP) in fixed cells can be unreliable if the fixing process does not preserve the total fluorescence intensity level or the spatial location relative to the living cells. In this study, we examine the effect of fixatives (formaldehyde, disuccinimidyl glutarate (DSG), dithiobis(succinimidyl) propionate (DSP) and m-maleimidobenzoyl-N-hydroxysuccinimidyl ester (MBS)), fixative buffers and the cross-linking times on the fluorescent intensity of soluble enhanced GFP (EGFP) expressed within NIH 3T3 cells. The total fluorescence intensity within individual cells during the fixation process was measured in an automated fluorescence microscope. Our results show that choice of fixative, the fixing solution and the cross-linking time were important for minimizing EGFP losses during fixing. The optimal fixation condition for these cells was identified to be the MBS cross-linker in a microtubule stabilizing buffer. After an 8 h fixation, greater than 90 % of the initial GFP fluorescence within cells was preserved. This was 3-fold higher than the GFP fluorescence remaining when the cells were fixed with 1 % paraformaldehyde in PBS. MBS treated cells could be permeabilized with 0.05 % Triton X-100 with little additional loss in fluorescence intensity. The MBS fixative could also preserve soluble fluorescent proteins in suspension cells, suggesting the fixation results are not cell line-specific. Direct imaging of the fixation process on fluorescent reporter cells provided insight into the effect of chemical fixatives on biological cells and can facilitate identification of fixation protocols that are fit-for-purpose for quantitative measurements.

cell biology↗