Search bioRxiv⌕ Search

Biology subjects

Grueneboom, A.

Publications and source records attributed to Grueneboom, A..

5 recordsLinked to original sources

TSP1/TGF-β1 drives arachidonic acid metabolism to orchestrate neutrophil swarming

Neutrophil swarming has emerged as a conserved multicellular behaviour observed across tissues and pathological contexts. Yet, the molecular cues and the spatially coordinated cellular circuits that drive the process of neutrophil swarming leading to cluster formation remain poorly understood. Here, we combine spatial proteomics and lipid profiling in a model of urinary tract infection to define the epithelial-immune circuits driving neutrophil cluster formation. We identify thrombospondin-1 (TSP1)-mediated activation of transforming growth factor beta 1 (TGF-{beta}1) as key epithelial signal licensing neutrophil clustering and enhancing bacterial control. Spatial lipid analysis further reveals that TSP1/TGF-{beta}1 signalling locally activates arachidonic acid metabolism in epithelial neutrophils, with 5-lipoxygenase dependent leukotriene synthesis required for swarm formation and infection clearance. These findings uncover a spatially coordinated defence mechanism in which epithelial-derived TSP1/TGF-{beta}1 engages neutrophil lipid metabolism to orchestrate neutrophil swarming behaviour and reinforce antibacterial immunity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=127 SRC="FIGDIR/small/688397v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@114ea92org.highwire.dtl.DTLVardef@345244org.highwire.dtl.DTLVardef@10520baorg.highwire.dtl.DTLVardef@1a7c0fe_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO C_FIG

immunology↗

Leonardo: a toolset to correct sample-induced artifacts in light sheet microscopy images

Selective plane illumination microscopy (SPIM, also known as light sheet fluorescence microscopy) is the method of choice for studying morphogenesis and function in biological specimens over extended periods, as it permits gentle and rapid volumetric imaging. In inhomogeneous samples, however, sample-induced artifacts, including light absorption, scattering, and refraction, can impact the image quality, particularly as the focal plane gets deeper into the sample. Here, we present Leonardo, the first toolbox designed to address the major sample-induced artifacts by using two modules: (1) DeStripe removes stripe artifacts in SPIM caused by light absorption while preserving fine sample structures; (2) Fuse reconstructs a single high-quality image from dualsided illumination and/or dual-sided detection, while eliminating blur and optical distortions caused by light scattering and refraction. The efficacy of Leonardo is validated on a wide range of biological samples, from minimally invasive experiments on sensitive specimens (translucent embryonic and optically opaque larval zebrafish) to cleared mouse samples up to two centimeters in size. We provide model code and a Napari-based graphical user interface, enabling the SPIM community to easily apply Leonardo to advance light sheet imaging of inhomogeneous and complex specimens.

bioinformatics↗

From breast cancer cell homing to the onset of early bone metastasis: dynamic bone (re)modeling as a driver of osteolytic disease

Breast cancer often metastasizes to bone causing osteolytic lesions. Structural and biophysical changes are rarely studied, yet are hypothesized to influence metastatic progression. Here, we developed a mouse model of early bone metastasis and multimodal 3D imaging to quantify cancer cell homing, dynamic bone (re)modeling and onset of bone metastasis. Using 3D light sheet fluorescence microscopy, we show eGFP+ cancer cells and small clusters in 3D (intact) bones. We detect early bone lesions using time-lapse in vivo microCT and reveal altered bone (re)modeling in absence of detectable lesions. With a new microCT image analysis tool, we detect and track the growth of early bone lesions over time. We show that cancer cells home in all bone compartments, while osteolytic lesions are only detected in the metaphysis, a region of high (re)modeling. Our study provides novel insights of dynamic bone (re)modeling as a driver during the early phase of metastasis.

bioengineering↗

Peyers Patch B cells undergo cell death via neutrophil-released toxic DNA following sterile tissue injury

Lymphocyte contraction (LC) in central immune organs is a concomitant of sterile tissue injury, for example after stroke. Intestinal Peyers patches (PP) harbor large numbers of B cells, but how sterile tissue injury leads to LC in PP has not been explored. We observed rapid and macroscopically evident shrinkage of PP after stroke and myocardial infarction. Light-sheet fluorescence microscopy and flow cytometry revealed a strong reduction in the number of PP-resident B cells. Mechanistically, tissue injury triggered the activation of neutrophils that released B cell-toxic neutrophil extracellular traps (NETs) decorated with citrullinated histone-H3. Antibody-mediated or genetically induced neutrophil-loss, NETs-degradation or blockade of their generation completely reversed B cell loss and preserved the tissue architecture of PP. We also found NET-like elements in human post-stroke plasma. Hence, we propose that targeting NET-generation or -function counteracts post-injury B cell contraction in PP and thereby maintains immune homeostasis at mucosal barriers. In briefHigh numbers of B cells reside in the intestinal Peyers patches. Tuz et al. revealed that in response to sterile tissue injury, activated neutrophils release histone-decorated DNA into the circulation which induces B cell death. The loss of B cells results in the shrinkage of Peyers patches and reduced amounts of secretory IgA. HighlightsO_LIStroke and myocardial infarction induce the melting of Peyers patch C_LIO_LILight-sheet microscopy and cytometry revealed B cell loss in Peyers patch C_LIO_LIPost-injury activated neutrophils release NETs and trigger B cell death C_LIO_LIInhibition of NETs rescues B cell loss and degeneration of Peyers patch C_LI

immunology↗

Rapid and fully automated blood vasculature analysis in 3D light-sheet image volumes of different organs

Blood vasculature represents a complex network of vessels with varying lengths and diameters that are precisely organized in space to allow proper tissue function. Light-sheet fluorescence microscopy (LSFM) is very useful to generate tomograms of tissue vasculature with high spatial accuracy. Yet, quantitative LSFM analysis is still cumbersome and available methods are restricted to single organs and advanced computing hardware. Here, we introduce VesselExpress, an automated software that reliably analyzes six characteristic vascular network parameters including vessel diameter in LSFM data on average computing hardware. VesselExpress is ~100 times faster than other existing vessel analysis tools, requires no user interaction, integrates batch processing, and parallelization. Employing an innovative dual Frangi filter approach we show that obesity induces a large-scale modulation of brain vasculature in mice and that seven other major organs differ strongly in their 3D vascular makeup. Hence, VesselExpress transforms LSFM from an observational to an analytical working tool.

bioinformatics↗