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bioRxiv2024

Identification of V. parvula and S. gordonii adhesins mediating co-aggregation and its impact on physiology and mixed biofilm structure

The dental plaque is a polymicrobial community where biofilm formation and co-aggregation, the ability to bind to other bacteria, play a major role in the construction of an organized consortium. One of its prominent members is the anaerobic diderm Veillonella parvula, considered as a bridging species, which growth depends on lactate produced by oral Streptococci. Understanding how V. parvula co-aggregates and the impact of aggregation has long been hampered due to the lack of appropriate genetic tools. Here we studied co-aggregation of the naturally competent strain V. parvula SKV38 with various oral bacteria and its effect on cell physiology. We show that V. parvula requires different trimeric autotransporters of the type V secretion system to adhere to oral Streptococci and Actinomyces. In addition, we describe a novel adhesin of Streptococcus gordonii, VisA (SGO_2004), as the protein responsible for co-aggregation with V. parvula. Finally, we show that co-aggregation does not impact cell-cell communication, which is mainly driven by environmental sensing, but plays an important role in the architecture and species distribution within the biofilm.

microbiology↗

bioRxiv2024

Physiological and Molecular Responses of Projected Future Temperatures on Potato Tuberization

Potato (Solanum tuberosum L.) is one of the most important food crops globally and is especially vulnerable to heat stress. Significant knowledge gaps remain however, in our understanding of the developmental mechanisms associated with tuber responses to heat stress. This study uses whole-plant physiology, transcriptomics, and hormone profiling to gain insights into the mechanisms associated with heat stress impacts on potato tuber development. When plants were grown in projected future temperature conditions, levels of abscisic acid (ABA) were significantly decreased in leaf and tuber tissues while rates of leaf carbon assimilation and stomatal conductance were not significantly affected. While plants grown in elevated temperature conditions initiated more tubers on average per plant, there was a significant decrease (66%) in mature tubers at final harvest. We hypothesize that reduced tuber yields at elevated temperatures are not due to reductions in tuber initiation, but due to impaired tuber filling. Transcriptomic analysis found significant changes in transcript expression for genes related to response to ABA, heat and auxin biosynthetic process. The known tuberization repressor genes SELF PRUNING 5G (StSP5G) and CONSTANS-LIKE1 (StCOL1) were found to be differentially expressed in tubers grown in elevated temperatures. IDENTITY OF TUBER 1 (StIT1) and TIMING OF CAB EXPRESSION 1 (StTOC1) are other known tuberization genes that displayed distinct expression patterns in elevated versus ambient temperatures but were not differentially expressed. This work highlights potential gene targets and key developmental stages associated with tuberization to development more heat tolerant potatoes.

plant biology↗

bioRxiv2024

Early life stress induced sex-specific changes in behavior is paralleled by altered locus coeruleus physiology in BALB/cJ mice

Adverse childhood experiences have been associated with many neurodevelopmental and affective disorders including attention deficit hyperactivity disorder and generalized anxiety disorder, with more exposures increasing negative risks. Sex and genetic background are biological variables involved in adverse psychiatric outcomes due to early life trauma. Females in general have an increased prevalence of stress-related psychopathologies beginning after adolescence, indicative of the adolescent time period being a female-specific sensitive period. To understand the underlying neuronal components responsible for this relationship between genetic background, sex, stress/trauma, and cognitive/affective behaviors, we assessed behavioral and neuronal changes in a novel animal model of early life stress exposure. Male and female BALB/cJ mice that express elevated basal anxiety-like behaviors and differences in monoamine associated genes, were exposed to an early life variable stress protocol that combined deprivation in early life with unpredictability in adolescence. Stress exposure produced hyperlocomotion and attention (5 choice serial reaction time task) in male and female mice along with female-specific increased anxiety-like behavior. These behavioral changes were paralleled by reduced excitability of locus coeruleus (LC) neurons, due to resting membrane potential hyperpolarization in males and a female specific increase in action potential delay time. These data describe a novel interaction between sex, genetic background, and early life stress that results in behavioral changes in clinically-relevant domains and potential underlying mechanistic lasting changes in physiological properties of neurons in the LC. HIGHLIGHTSO_LIBALB/cJ mice exposed to early life stress are hyperactive in adolescence and displayed attention deficits in adulthood. C_LIO_LIOnly female BALB/cJ mice develop increased anxiety in adolescence after early life stress. C_LIO_LIEarly life stress causes reduced excitability of locus coeruleus neurons in BALB/cJ mice. C_LIO_LIOnly locus coeruleus neurons from female BALB/cJ mice exposed to early life stress displayed an increase in action potential delay time upon depolarization. C_LI

neuroscience↗

bioRxiv2024

Morpho-physiological and transcriptomic responses of field pennycress to waterlogging

Field pennycress (Thlaspi arvense) is a new biofuel winter annual crop with extreme cold hardiness and a short life cycle, enabling off-season integration into corn and soybean rotations across the Midwest. Pennycress fields are susceptible to winter snow melt and spring rainfall, leading to waterlogged soils. The objective of this research was to determine if waterlogging during the reproductive stage had a significant effect on gene expression, morphology, physiology, recovery, and yield of two pennycress lines (SP32-10 and MN106). In a controlled environment, total pod number, shoot/root dry weight, and total seed count/weight were significantly reduced in SP32-10 in response to waterlogging, whereas primary branch number, shoot dry weight, and single seed weight were significantly reduced in MN106. This indicated waterlogging had a greater negative impact on seed yield in SP32-10 than MN106. The number of differentially expressed genes (DEGs) between waterlogged and control roots were doubled in MN106 (3,424) compared to SP32-10 (1,767). Functional enrichment analysis of upregulated DEGs revealed Gene Ontology (GO) terms associated with hypoxia and decreased oxygen, with genes in these categories involved in alcoholic fermentation and glycolysis. Interestingly, MN106 waterlogged roots exhibited significant stronger upregulation of these genes than SP32-10. Additionally, downregulated DEGs revealed GO terms associated with cell wall biogenesis and secondary metabolite biogenesis, indicating suppressed growth and energy conservation. Together, these results reveal the reconfiguration of cellular and metabolic processes in response to the severe energy crisis invoked by waterlogging in pennycress.

plant biology↗

bioRxiv2024

A simple inland culture system provides insights into ascidian post-embryonic developmental physiology

Maintenance and breeding of experimental organisms are fundamental to life sciences, but both initial and running costs, and hands-on zootechnical demands can be challenging for many laboratories. Here, we aimed to further develop a simple protocol for reliable inland culture of tunicate model species of the Ciona genus. We cultured both Ciona robusta and Ciona intestinalis in controlled experimental conditions, with a focus on dietary variables, and quantified growth and maturation parameters. From statistical analysis of these standardized datasets, we gained insights into the post-embryonic developmental physiology of Ciona, and inferred an improved diet and culturing conditions for sexual maturation. We showed that body length is a critical determinant of both somatic and sexual maturation, which suggests the existence of systemic control mechanisms of resource allocation toward somatic growth or maturation, and supports applying size selection as a predictor of reproductive fitness in our inland culture, to keep the healthiest animals at low density in the system. In the end, we successfully established a new protocol, including size selection, to promote both sperm and eggs production. Our protocol using small tanks will empower researchers to initiate inland Ciona cultures with low costs and reduced space constraints.

developmental biology↗

bioRxiv2024

Dialogues in colour and behaviour - Integration of complex signalling traits and physiology

Animal communication can be complex, often involving multiple static and dynamic traits. The extent to which these traits are correlated can elucidate their function as either redundant or multiple messages. Using the agamid lizard, Psammophilus dorsalis, as a model system we examined patterns of trait expression and the role of steroid hormones in mediating these traits during social interactions. We staged male-male interactions in the lab and measured the repertoire of display behaviour and colours, which change dynamically in the visible and ultraviolet ranges in different body regions. Additionally, we measured testosterone and corticosterone levels before and after the social trials. Our results show that within behaviour and colour trait categories, components were strongly correlated within individuals, suggesting either a shared physiological pathway or redundant information content. However, across trait categories, correlation patterns varied. The chromatic contrast of the (yellow) dorsal region of lizards was correlated with both body size and level of aggression, whereas the size of UV patches was correlated with body size only. We also found a negative association between baseline corticosterone levels, body size and dorsal yellow chromatic contrast, suggesting a mechanistic link between these traits. However, social interaction induced testosterone and corticosterone levels were uncorrelated with the expression of the dynamic behavioural and colour displays during the social interactions itself. Notably, the intensity of colour and behavioural displays of males were matched by their opponents. Overall, our results suggest that multiple signalling traits can ensure both redundancy as well as provide multiple messages to receivers, thus improving the robustness of information transfer, particularly during competitions which have high fitness consequences.

animal behavior and cognition↗

bioRxiv2024

Vapor-based Fixation of Pulmonary Tissue in its Physiological State: A Novel Approach to Histological Validation of Ultra High Resolution Phase Contrast CT in Human Sized Lungs

Lung diseases continue to present a major burden on public health. Therefore, improving the process of diagnosis by the development of novel imaging techniques is of great importance. In this perspective, phase sensitive CT imaging techniques such as propagation based imaging (PBI) might play an important role as they allow increasing the spatial resolution at very low x-ray dose levels that are comparable to clinical CT. However, the development of such methods is not only hindered by technological problems but also by the lack of precise validation strategies. We adapted formaldehyde (FA) vapor fixation to demonstrate that fresh porcine lungs that have been investigated by PBI can be fixed in their physiological shape and studied by multi-scale microCT imaging as well as classical histology. In addition, we show that FA vapor fixed pig lungs can be scanned by PBI without visible deterioration of image quality compared to fresh tissue. This opens the possibility of fixing and storing, for instance, human lung tissue before performing a PBI experiment, which in turn allows to study pathological changes in human lungs without questioning the translate-ability of findings in pig lung. The setup can be used by any interested researchers.

pathology↗

bioRxiv2024

Pericytes require physiological oxygen tension to maintain phenotypic fidelity.

Pericytes function to maintain tissue homeostasis by regulating capillary blood flow and maintaining endothelial barrier function. Pericyte dysfunction is associated with various pathologies and has recently been found to aid cancer progression. Despite having critical functions in health and disease, pericytes remain an understudied population due to a lack of model systems which accurately reflect in vivo biology. In this study we developed a protocol to isolate and culture murine lung, brain, bone, and liver pericytes, that maintains their known phenotypes and functions. We demonstrate that pericytes, being inherently plastic, benefit from controlled oxygen tension culture conditions, aiding their expansion ex vivo. Primary pericytes grown in physioxia (10% O2 for lung; 5% O2 for brain, bone, and liver) also better retain pericyte phenotypes indicated by stable expression of characteristic transcriptional and protein markers. In functional tube formation assays, pericytes were observed to significantly associate with endothelial junctions. Importantly, we identified growth conditions that limit expression of the plasticity factor Klf4 to prevent spontaneous phenotypic switching in vitro. Additionally, we were able to induce pathological pericyte phenotypic switching in response to metastatic stimuli to accurately recapitulate in vivo biology. Here, we present a robust method for studying pericyte biology in both physiology and disease.

cell biology↗

bioRxiv2024

Neighbor sensing through rhizodeposits in sorghum affects plant physiology and productivity

Plant-plant interactions play a crucial role in shaping the growth environment for crops, impacting their productivity and stress response. The interaction between plants aboveground has been studied and incorporated into breeding programs that select for plants that reduce aboveground competition between plants. However, few studies have focused on belowground interactions, and these looked at combined interactions and root partitioning in the soil. This study focuses on the developmental and physiological responses of sorghum (Sorghum bicolor L.) genotypes to neighboring sorghum plants. In this study, we used two growing methods: i) a focal plant surrounded by neighboring plants in the same pot but without shading, and ii) a focal plant grown either alone or surrounded by neighbors, irrigated with nutrient solution passed through pots (leachates) with or without plants. Our results showed that the presence of neighbors in the same pot led to reduced size-dry weight height, and leaf area of the focal plant. In addition, the presence of neighbors reduced stomatal conductance and PSII quantum yield. While the response direction was similar across tested genotypes, the magnitude varied. The results were repeated when neighboring plants were not grown in the same pot, but the nutrient solution passed through the root system of plants of the neighboring genotype. Furthermore, we saw a reduction in assimilation rate and stomatal conductance when plants were exposed to either the physical presence of neighbors or leachate. We did not find differences in root architecture in either treatment. These results show plants change their growth in response to neighbors and that the signal is carried through the liquid phase of the soil. Our findings provide insights into sorghum plants responses to below-ground signaling from neighboring plants and lay the foundation for future studies enabling increased crop performance under high-density planting conditions.

plant biology↗

bioRxiv2024

Dynamic imaging of myelin pathology in physiologically preserved human brain tissue using third harmonic generation microscopy

Myelin pathology is known to play a central role in disorders such as multiple sclerosis (MS) among others. Despite this, the pathological mechanisms underlying these conditions are often difficult to unravel. Conventional techniques like immunohistochemistry or dye-based approaches, do not provide a temporal characterization of the pathophysiological aberrations responsible for myelin changes in human specimens. Here, to circumvent this curb, we present a label-free, live-cell imaging approach of myelin using recent advancements in nonlinear harmonic generation microscopy applied to physiologically viable human brain tissue from post-mortem donors. Gray and white matter brain tissue from epilepsy surgery and post-mortem donors was excised. To sustain viability of the specimens for several hours, they were subjected to either acute or organotypic slice culture protocols in artificial cerebral spinal fluid. Imaging was performed using a femtosecond pulsed 1060 nm laser to generate second harmonic generation (SHG) and third harmonic generation (THG) signals directly from myelin and axon-like structures without the need to add any labels. Experiments on acute human brain slices and post-mortem human slice cultures reveal that myelin, along with lipid bodies, are the prime sources of THG signal. We show that tissue viability is maintained over extended periods during THG microscopy, and that prolonged THG imaging is able to detect experimentally induced subtle alterations in myelin morphology. Finally, we provide practical evidence that live-cell imaging of myelin with THG microscopy is a sensitive tool to investigate subtle changes in white matter of neurological donors. Overall, our findings support that nonlinear live-cell imaging is a suitable setup for researching myelin morphology in neurological conditions like MS.

neuroscience↗

bioRxiv2024

Reversible Transcriptomic Age Shifts from Physiological Stress in Whole Blood

We developed a genome-wide transcriptomic clock for predicting chronological age using whole blood samples from 463 healthy individuals. Our findings reveal profound age acceleration, up to 24.47 years, under perturbed homeostasis in COVID-19 patients, which reverted to baseline upon recovery. This study demonstrates that the whole blood transcriptome can track reversible changes in biological age induced by stressors in real physiological time, suggesting a potential role for anti-aging interventions in disease management.

bioinformatics↗

bioRxiv2024

Profiling the physiological impact of aberrant folded-state protein filamentation in cells

The formation of large polymeric structures such as cytoskeletal and enzyme filaments is crucial for normal cellular function. However, such filaments can also form due to mutations that create self-interactions at the surface of symmetric proteins. Often, the proteins forming these structures maintain a folded state and thereby differ from aggregates and amyloids that involve misfolding. We refer to this type of assemblies as agglomerates to mark this difference. While cells have quality control mechanisms to identify, buffer, and eliminate misfolded proteins, it is unclear whether similar mechanisms exist for agglomerates, or whether agglomerates are toxic to cells. Here, we profiled the physiological impact of mutation-induced folded-state protein filamentation in yeast cells. First, we devised a simple strategy to distinguish fluorescently labeled proteins forming agglomerates versus aggregates. We then profiled exogenous protein agglomerates in terms of their recognition by known quality control mechanisms, their effects on specific cellular processes and overall fitness on S. cerevisiae cultures. We found that agglomerates do not colocalize with the proteostasis machinery and do not result in measurable fitness defects. Proteomics profiling of cells expressing the wild type protein, agglomerating or misfolded variants revealed a consistent picture, with only minor, agglomerate-size-dependent changes observed and linked to the cell-wall and plasma-membrane proteins. Overall, our findings indicate that agglomerates form mostly benign structures in cells when compared to aggregates, and thereby offer a promising route for synthetic biology applications. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=146 SRC="FIGDIR/small/612878v1_ufig1.gif" ALT="Figure 1"> View larger version (84K): org.highwire.dtl.DTLVardef@7136a4org.highwire.dtl.DTLVardef@ba62dborg.highwire.dtl.DTLVardef@b02bbaorg.highwire.dtl.DTLVardef@6cbf9_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2024

Physiologically based demographic model/GIS analyses of thirteen invasive species in Africa: why the biology matters

Globally, research and policy groups often lack the expertise to develop appropriate models to analyze agroecological and invasive species problems holistically to inform management and quarantine policy development under extant and climate change over wide geographic landscapes. Off-the-shelf species distribution models (SDM) correlate weather and other variables to records of species presence and have become the mainstay for predicting the geographic distribution and favorability of invasive species (Elith 2017). However, SDM analyses lack the capacity to examine the underpinning dynamics of agroecosystems required to inform policy and develop management strategies. We propose that age-structured physiologically based demographic models (PBDMs) can solve important aspects of this challenge as they can be used to examine prospectively species dynamics locally as well as their potential geographic distribution and relative abundance across vast areas independent of presence records. PBDMs fall under the ambit of time-varying life tables (TVLTs; cf. Gilbert et al. 1976) and capture the weather driven biology, dynamics, and interactions of species, and can be used to examine the system from the perspective of any of the interacting species. Here, we use the PBDM structure to examine the dynamics across Africa of thirteen invasive species from various taxa having diverse biology and trophic interactions (see Gutierrez 1996, Gutierrez and Ponti 2013a). PBDMs are perceived to be difficult to develop, hence the raison detre is to show this is not the case and illustrate their utility invasive and endemic agricultural and medical/veterinary pest species at the local and the large geographic scale of Africa. We note that PBDMs provide a structure for continued model improvements. The development of open access software is proposed to facilitate PBDM development by non-experts emphasizing the crucial role of sound biological data on species responses to weather and to other species in a multi-trophic, interactions, and provide a guide for collecting the appropriate biological data. While the emphasis is on plant/arthropod interactions, models of diseases can be accommodated. The Supplemental Materials summarizes a large array of heritage PBDMs reported in the literature based on the methods outline herein, noting that the same model structure can be used to analyze and manage non pest species.

ecology↗

bioRxiv2024

Contrasting Cognitive, Behavioral, and Physiological Responses to Breathwork vs. Naturalistic Stimuli in Reflective Chamber and VR Headset Environments

The MindGym, a novel immersive technology utilizing a reflective chamber environment, was developed to create standardized experiential content, including anxiolytic experiences. This study examined whether therapeutic experiences originally created in the MindGym could maintain their efficacy when delivered via 360-degree recordings through virtual reality (VR) headsets. A randomized controlled trial (N=126) compared anxiety reduction, cognitive performance, and physiological responses across four conditions: MindGym and VR platforms, each delivering either breathwork or rain stimuli. Results demonstrated significant improvements across all conditions in cognitive performance (Trail Making Test RTACC, p.fdr<.001; Architex Total Speed, p.fdr<.001) and anxiety reduction (STAI, p.fdr<.001). Breathwork conditions produced greater decreases in breath rate compared to rain stimuli (p.fdr=.002). Treatment responses were moderated by individual differences, with absorption (MODTAS) predicting both awe (p.fdr=.004) and ego dissolution (p.fdr=.015), while openness to experience interacted with stimuli type to influence anxiety reduction (p.fdr=.038). The anxiolytic effects originally generated in the MindGym maintained full efficacy when translated to VR delivery, with no significant differences in effectiveness or immersion between the original environment and its virtual reproduction. These findings establish the MindGym as a viable content creation platform for immersive, anxiety-reducing experiences that can be successfully adapted to more accessible delivery systems, while highlighting the potential for personalization based on individual differences. Future research should investigate the translation of more complex MindGym-generated experiences to expand accessible anxiety management tools.

neuroscience↗

bioRxiv2024

Physiological response of Microcystis aeruginosa exposed to aqueous extracts of Pistia stratiotes and Pontederia crassipes

Macrophyte extracts inhibit cyanobacteria growth, offering a sustainable solution for bloom control. The present study aimed to evaluate Microcystis aeruginosas response to aqueous extracts obtained from the dried biomass of Pistia stratiotes L. and Pontederia crassipes Mart. Solms. Physiological parameters analyzed included growth, photosynthesis, and antioxidative response. Reactive oxygen species generation and the chemical profile of the aqueous extracts were analyzed. At 4.0 g L-1, both extracts inhibited cyanobacterial growth in 6 days. P. stratiotes extract achieved 100% inhibition, while P. crassipes extract reached 60%. P. stratiotes extract showed higher photosynthetic inhibition (99% vs. 12% for P. crassipes). This was related to the downregulation of the psbA gene (coding for the photosystem II protein D1). Exposure to both extracts increased intracellular reactive oxygen species content in cyanobacterial cells and increased peroxiredoxin gene (prxA) transcripts. This response was not noted for sod (superoxide dismutase) transcripts, although SOD enzymatic activity increased in cultures exposed to P. stratiotes extracts. Upon incubation of the macrophyte extracts with M. aeruginosa cultures, phenol concentrations decreased, and their general metabolic profile changed. Thus, P. stratiotes extract outperformed P. crassipes, inhibiting M. aeruginosa growth, affecting photosystem II, and inducing oxidative stress. HighlightsO_LIAqueous extracts from dried biomass of P. stratiotes and P. crassipes inhibited M. aeruginosa growth. C_LIO_LIP. stratiotes extract suppressed photosystem II activity, while P. crassipes did not C_LIO_LIBoth extracts elicited ROS production in cells. C_LIO_LIPeroxiredoxin gene expression upregulated by extract exposure. C_LIO_LIP. stratiotes extract increased SOD activity in cells. C_LI

microbiology↗

bioRxiv2024

A membrane-targeted photoswitch restores physiological ON/OFF responses to light in the degenerate retina

The lack of effective therapies for visual restoration in Retinitis pigmentosa and macular degeneration has led to the development of new strategies such as optogenetics and retinal prostheses. However, visual restoration is poor due to the massive light-evoked activation of retinal neurons, regardless of the segregation of visual information in ON and OFF channels, essential for contrast sensitivity and spatial resolution. Here, we show that Ziapin2, a membrane photoswitch which modulates neuronal capacitance and excitability in a light-dependent manner, is capable of reinstating, in two distinct genetic models of photoreceptor degeneration, brisk and sluggish ON, OFF, and ON-OFF responses in retinal ganglion cells evoked by full-field stimuli, with reactivation of their excitatory and inhibitory conductances. Intravitreally injected Ziapin2 in fully blind rd10 mice restored light-driven behavior and optomotor reflexes. The results indicate that Ziapin2 is a promising molecule for reinstating physiological visual responses in the late stages of retinal degeneration.

neuroscience↗

bioRxiv2024

Shaping Kale Morphology and Physiology Using Different LED Light Recipes

Light serves as a fundamental factor in plant development, both as an energy source and as an environmental cue. With the advent of light-emitting diode (LED) technology, light can be precisely manipulated to influence key plant traits. Here, we assess effects of light intensity and spectral composition on the growth and physiology of Kale (Brassica oleracea). Kale is known for its phenotypic plasticity and nutritional composition, making it a crop well-suited for indoor cultivation either as microgreens or as large leafy plants. Here, we employ a combination of advanced phenotyping, computer vision, gas chromatography-mass spectrometry (GC-MS) metabolomics, and liquid chromatography-mass spectrometry (LC-MS)-based quantitative proteomics to characterize the molecular changes that underpin light-dictated differences in the growth and metabolism of two different commercially grown kale cultivars under different light intensities and spectral compositions. We identify time-of-day and cultivar-specific light intensity and spectral composition-induced changes related to growth, shade avoidance, photosynthesis and several aspects of nutritional composition, including amino acids, glucosinolates and carotenoids. Our results offer a key resource to the plant community and demonstrate the translational potential of light manipulation in tailoring kale growth and nutritional content for enhanced crop productivity and/or health benefits, while simultaneously offering a more cost-effective solution for contemporary agricultural challenges. Significance StatementThe effects of light intensity and spectral composition differentially affect the diel molecular responses of Kale (Brassica oleracea). Our results demonstrate the translational potential of light manipulation in tailoring plant growth and nutritional content for enhanced crop productivity.

plant biology↗

bioRxiv2024

Metabolism-oriented compound screen in physiological culture conditions identifies a NAMPT inhibitor highly effective against drug-naive and -resistant melanoma cells

Many melanoma patients do not respond to therapy or rapidly develop resistance to MAPK pathway inhibitors and immune checkpoint blockade treatments, highlighting the urgent need for additional therapeutic strategies for these patients. To identify compounds that target drug-naive and -resistant melanoma cells (Encorafenib/Binimetinib-resistant), we performed a screen using a metabolism-oriented compound library in different cell culture media and growth conditions (2D and 3D). The efficacy of several compounds varied considerably under changing test conditions, but importantly, we also detected compounds that work across all tested conditions. In general, drug activity was reduced under hypoxia and in 3D spheroids. Thorough validation was performed for drugs showing potency in all conditions with a focus on efficacy in 3D spheroids grown in an in- house physiological culture medium. Using hydrogel matrix-embedded multi-cell type 3D models, we found that FK866, a nicotinamide phosphoribosyltransferase (NAMPT) inhibitor, is very potently suppressing melanoma cell growth while not affecting the growth of healthy cells such as fibroblasts and endothelial cells.

cancer biology↗