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Jonigk, D. D.

Publications and source records attributed to Jonigk, D. D..

8 recordsLinked to original sources

Single-cell and spatial transcriptomics resolve airway obliteration in bronchiolitis obliterans syndrome

Background: Chronic lung allograft dysfunction (CLAD) is the leading cause of death beyond the first year after lung transplantation, and its most frequent phenotype is bronchiolitis obliterans syndrome (BOS), a fibrotic small-airway disease. Mechanistic work has focused on the immune compartment, yet intensified immunosuppression does not alter established disease. Aim: To resolve which structural cell states populate the BOS graft and how they are spatially organized during airway obliteration. Methods: We profiled explanted lungs from 33 BOS patients undergoing re-transplantation and 33 controls, combining single-nucleus RNA sequencing (14 BOS, 13 controls) with targeted spatial transcriptomics of 108 regions (27 BOS, 24 controls) and multiplex immunofluorescence validation. Single-nucleus data were integrated with a published restrictive allograft syndrome (RAS) atlas. Results: Across 175,128 nuclei and 1.67 million spatially resolved cells, BOS lungs harbored a profibrotic circuit of Aberrant Basaloid cells and CTHRC1+ fibrotic fibroblasts previously described in fibrotic lung diseases, including RAS. Spatial mapping identified a CXCL14+TNC+ injury-associated basal cell state arising early in the obliterative cascade, identifying basal cells as their major reservoir. CTHRC1+ fibroblasts expanded subepithelially replacing resident peribronchial fibroblasts, alongside a peribronchial vascular shift toward systemic venous endothelium. The circuit extended beyond the airway wall to the alveolar interface, defining two convergent remodeling fronts. Conclusion: BOS engages structural-cell circuits largely shared with RAS and fibrotic lung diseases, but along an airway-centered rather than parenchyma-centered axis. CLAD thus emerges as a spatial rather than cellular spectrum, defined by anatomical distribution more than cell identity. Shared structural programs may therefore be targetable across CLAD phenotypes.

cell biology↗

A multicenter spatial transcriptomics atlas of human tuberculosis and non-tuberculous mycobacterial disease

Granulomas are the hallmark of mycobacterial (MB) infections, forming structured immune environments that contain bacteria but also drive disease persistence. However, their spatial and functional organization remains unclear. Using spatial RNA sequencing on 38 patient samples, we identified five distinct granuloma niches: a necrotic core, an immune-activated inner niche, an inflammatory and an extracellular matrix (ECM)-remodeling middle niche, an outer structural niche, and a tertiary lymphoid structure niche supporting antigen presentation. Immune activity peaks in the inner niche, transitioning to fibrosis at the periphery. Lymph node granulomas display reduced fibroblast involvement but stronger JAK-STAT activation. Mycobacterium tuberculosis (MTB) granulomas exhibit heightened JAK-STAT and IFN-{gamma} signaling, while non-tuberculous mycobacteria (NTM) granulomas show increased hypoxia signatures. Compared to sarcoidosis, MB granulomas feature a structured adaptive immune response, marked by the clustering of plasma cells. Our findings, accessible via https://lab-li.ciim-hannover.de/mb-granuloma/, define key disease signatures, guiding biomarker discovery and therapeutic targeting in granuloma-related diseases.

bioinformatics↗

Ablation of B cell-derived IL-10 increases tuberculosis resistance

Due to the historical dogma, that host defense against intracellular pathogens is mediated by cell-mediated immunity, B cells have been considered unimportant in providing protection against Mycobacterium tuberculosis (Mtb) and remained understudied for decades. However, emerging evidence suggests a more complex and multifaceted role for B cells in tuberculosis (TB) immunity. They accumulate at the side of infection in both animal models and human TB patients, suggesting a potential link to protective immunity. Still, the diverse roles of B cells in TB immunity continue to be unraveled. Apart from antibodies, B cells produce a wide range of cytokines, which can influence the local immune response. Here we addressed the relevance of interleukin 10 (IL-10) secreting B cells in long-term control of the Mtb Beijing strain HN878. Our research highlights the previously unknown role of B cell-derived IL-10 as a negative regulator of protective immunity in TB. For the first time, we demonstrate that mice lacking B cell-derived IL-10 show increased resistance to aerosol Mtb infection, as evidenced by a delayed onset of clinical symptoms and prolonged survival. Notably, this effect was significantly more pronounced in males compared to females, and was accompanied by male-specific immune alterations, indicating a previously unknown sex-specific regulatory role of B cell-derived IL-10 during Mtb infection.

immunology↗

Aberrant and Ectopic Cell Populations of the Fibrotic Pushing Border in Restrictive Allograft Syndrome after Lung Transplantation

RationaleRestrictive allograft syndrome (RAS) is a major cause of mortality in patients following lung transplantation due to rapid progressive fibrosis in the pulmonary graft. We have only limited knowledge of the cellular and molecular mechanisms that characterize the fibrosis in the RAS lung. ObjectiveTo elucidate cellularly-resolved transcriptomic and histologic characteristics of the structural cells in human RAS lungs. MethodsSingle-nuclei RNA-sequencing was performed in peripheral lung tissues from 15 RAS patients undergoing lung re-transplantation, and from 9 healthy control lungs. Findings were validated and complemented by various histologic techniques, including immunofluorescence, RNAscope, combined Elastica van Gieson-immunohistochemistry stains, and micro-CT scans. Measurement and Main resultsDifferential gene expression analysis of our single-nuclei RNA-sequencing data revealed in human RAS lungs previously undescribed and uniquely distributed aberrant basaloid cells, ectopic COL15A1+ vascular endothelial cells, and CTHRC1+ fibrotic fibroblasts, all first characterized in idiopathic pulmonary fibrosis (IPF). In contrast to IPF, RAS lacks the cellular equivalent of bronchiolization. Histologic stains confirmed our transcriptomic discoveries and disclosed distinctive distribution patterns: Aberrant basaloid cells are primarily localized at the edge of the fibrotic pushing border, forming together with the juxtaposed CTHRC1+ fibrotic fibroblasts the fibrotic niche of alveolar fibroelastosis (AFE), the histopathological hallmark in RAS lungs. On the endothelial side, PRX+ alveolar microvasculature is lost in AFE areas. Micro-CT scans revealed that blood supply, now facilitated by expanded and ectopic COL15A1+ VE cells, changes from pulmonary to systemic perfusion. Last, our data reveals potential therapeutically-modifiable expression patterns in RAS, including genes coding for the integrin subunits v{beta}6, activators of TGF{beta}. ConclusionConsidering the marked clinical, histologic and etiologic dissimilarities of RAS and IPF, our snRNAseq study revealed a surprising general principle of cellular and molecular pathogenesis in the fibrosing lung: the entity-spanning composition of the fibrotic niche by a) aberrant basaloid cells localized at the fibrotic pushing border, b) ectopic COL15A1+ vascular ECs and c) effector CTHRC1+ fibrotic fibroblasts. This general principle justifies a flexible but cellular pathogenesis-guided transferability of potential therapeutic approaches between progressive fibrotic lung diseases.

cell biology↗

Multidimensional Analysis of the Adult Human Heart in Health and Disease using Hierarchical Phase-Contrast Tomography (HiP-CT)

Cardiovascular diseases (CVDs) are a leading cause of death worldwide. Current clinical imaging modalities provide resolution adequate for diagnosis but are unable to provide detail of structural changes in the heart, across length-scales, necessary for understanding underlying pathophysiology of disease. Hierarchical Phase-Contrast Tomography (HiP-CT), using new (4th) generation synchrotron sources, potentially overcomes this limitation, allowing micron resolution imaging of intact adult organs with unprecedented detail. In this proof of principle study (n=2), we show the utility of HiP-CT to image whole adult human hearts ex-vivo: one control without known cardiac disease and one with multiple known cardiopulmonary pathologies. The resulting multiscale imaging was able to demonstrate exemplars of anatomy in each cardiac segment along with novel findings in the cardiac conduction system, from gross (20 um/voxel) to cellular scale (2.2 um/voxel), non-destructively, thereby bridging the gap between macroscopic and microscopic investigations. We propose that the technique represents a significant step in virtual autopsy methods for studying structural heart disease, facilitating research into abnormalities across scales and age-groups. It opens up possibilities for understanding and treating disease; and provides a cardiac blueprint with potential for in-silico simulation, device design, virtual surgical training, and bioengineered heart in the future.

pathology↗

Preparation of large biological samples for high-resolution, hierarchical, multi-modal imaging

Imaging the different scales of biological tissue is essential for understanding healthy organ behavior and pathophysiological changes. X-ray micro-tomography using both laboratory ({micro}CT) and synchrotron sources (sCT) is a promising tool to image the 3D morphology at the macro- and micro-scale of large samples, including intact human organs. Preparation of large samples for high resolution imaging techniques remains a challenge due to limitations with current methods, such as sample shrinkage, insufficient contrast, movement of the sample and bubble formation during mounting or scanning. Here, we describe a protocol to prepare, stabilize, and image large soft-tissue samples with X-ray microtomography. We demonstrate the protocol using intact human organs and Hierarchical Phase-Contrast Tomography (HiP-CT) imaging at the European Synchrotron Radiation Facility, but the protocol is equally applicable to a range of biological samples, including complete organisms, for both laboratory and synchrotron source tomography. Our protocol enhances the contrast of the sample, while preventing sample motion during the scan, even in case of different sample orientations. Bubbles trapped during mounting and those formed during scanning (in case of synchrotron X-ray imaging) are mitigated by multiple degassing steps. The sample preparation is also compatible with magnetic resonance imaging (MRI), CT, and histological observation. We describe a protocol for sample preparation and mounting which requires 25 to 34 days for a large organ such as an intact human brain or heart. This preparation time varies depending on the composition, size, and fragility of the tissue. Use of the protocol enables scanning of intact organs with a diameter of 150 mm with a local pixel size of one micron using HiP-CT.

physiology↗

A multiscale X-ray phase-contrast tomography dataset of whole human left lung

Technological advancements in X-ray imaging using bright and coherent synchrotron sources now allows to decouple sample size and resolution, while maintaining high sensitivity to the microstructure of soft, partially dehydrated tissues. The recently developed imaging technique, hierarchical phase-contrast tomography, is a comprehensive approach to address the challenge of organ-scale (up to tens of centimeters) soft tissue imaging with resolution and sensitivity down to the cellular level. Using this technique, we imaged ex vivo an entire human left lung at an isotropic voxel size of 25.08 m along with local zooms down to 6.05 - 6.5 m and 2.45 - 2.5 m in voxel size. The high tissue contrast offered by the fourth-generation synchrotron source at the European Synchrotron Radiation Facility reveals complex multiscale anatomical constitution of the human lung from the macroscopic (centimeter) down to the microscopic (micrometer) scale. The dataset provides complete organ-scale 3D information of the secondary pulmonary lobules and delineates the microstructure of lung nodules with unprecedented detail.

physiology↗

Multiscale three-dimensional imaging of intact human organs down to the cellular scale using hierarchical phase-contrast tomography

Human organs are complex, three-dimensional and multiscale systems. Spatially mapping the human body down through its hierarchy, from entire organs to their individual functional units and specialised cells, is a major obstacle to fully understanding health and disease. To meet this challenge, we developed hierarchical phase-contrast tomography (HiP-CT), an X-ray phase propagation technique utilising the European Synchrotron Radiation Facilitys Extremely Brilliant Source: the worlds first high-energy 4th generation X-ray source. HiP-CT enabled three-dimensional and non-destructive imaging at near-micron resolution in soft tissues at one hundred thousand times the voxel size whilst maintaining the organs structure. We applied HiP-CT to image five intact human parenchymal organs: brain, lung, heart, kidney and spleen. These were hierarchically assessed with HiP-CT, providing a structural overview of the whole organ alongside detail of the organs individual functional units and cells. The potential applications of HiP-CT were demonstrated through quantification and morphometry of glomeruli in an intact human kidney, and identification of regional changes to the architecture of the air-tissue interface and alveolar morphology in the lung of a deceased COVID-19 patient. Overall, we show that HiP-CT is a powerful tool which can provide a comprehensive picture of structural information for whole intact human organs, encompassing precise details on functional units and their constituent cells to better understand human health and disease.

physiology↗