Newly synthesized glycoprotein profiling to identify molecular signatures of warm ischemic injury in donor lungs.

Despite recent technological advances such as ex vivo lung perfusion (EVLP), the outcome of lung transplantation remains unsatisfactory with ischemic injury being a common cause for primary graft dysfunction. New therapeutic developments are hampered by limited understanding of pathogenic mediators of ischemic injury to donor lung grafts. Here, to identify novel proteomic effectors underlying the development of lung graft dysfunction, using bioorthogonal protein engineering, we selectively captured and identified newly synthesized glycoproteins (NewS-glycoproteins) produced during EVLP with unprecedented temporal resolution of 4 h. Comparing the NewS-glycoproteomes in lungs with and without warm ischemic injury, we discovered highly specific proteomic signatures with altered synthesis in ischemic lungs, which exhibited close association to hypoxia response pathways. Inspired by the discovered protein signatures, pharmacological modulation of the calcineurin pathway during EVLP of ischemic lungs offered graft protection and improved posttransplantation outcome. In summary, the described EVLP-NewS-glycoproteomics strategy delivers an effective new means to reveal molecular mediators of donor lung pathophysiology and offers the potential to guide future therapeutic development.NEW & NOTEWORTHY This study developed and implemented a bioorthogonal strategy to chemoselectively label, enrich, and characterize newly synthesized (NewS-)glycoproteins during 4-h ex vivo lung perfusion (EVLP). Through this approach, the investigators uncovered specific proteomic signatures associated with warm ischemic injury in donor lung grafts. These signatures exhibit high biological relevance to ischemia-reperfusion injury, validating the robustness of the presented approach.

Repurposing Decellularized Lung to Generate Vascularized Fat.

Conventional therapies to address critically sized defects in subcutaneous adipose tissue remain a reconstructive challenge for surgeons, largely due to the lack of graft pre-vascularization. Adipose tissue relies on a dense microvasculature network to deliver nutrients, oxygen, nonadipose tissue-derived growth factors, cytokines, and hormones, as well as transporting adipose tissue-derived endocrine signals to other organ systems. This chapter addresses these vascularization issues by combining decellularized lung matrices with a step-wise seeding of patient-specific adipose-derived stem cells and endothelial cells to develop large-volume, perfusable, and pre-vascularized adipose grafts.

Extracellular matrix dynamics: tracking in biological systems and their implications.

The extracellular matrix (ECM) constitutes the main acellular microenvironment of cells in almost all tissues and organs. The ECM not only provides mechanical support, but also mediates numerous biochemical interactions to guide cell survival, proliferation, differentiation, and migration. Thus, better understanding the everchanging temporal and spatial shifts in ECM composition and structure - the ECM dynamics - will provide fundamental insight regarding extracellular regulation of tissue homeostasis and how tissue states transition from one to another during diverse pathophysiological processes. This review outlines the mechanisms mediating ECM-cell interactions and highlights how changes in the ECM modulate tissue development and disease progression, using the lung as the primary model organ. We then discuss existing methodologies for revealing ECM compositional dynamics, with a particular focus on tracking newly synthesized ECM proteins. Finally, we discuss the ramifications ECM dynamics have on tissue engineering and how to implement spatial and temporal specific extracellular microenvironments into bioengineered tissues. Overall, this review communicates the current capabilities for studying native ECM dynamics and delineates new research directions in discovering and implementing ECM dynamics to push the frontier forward.

Reconstructing the pulmonary niche with stem cells: a lung story.

The global burden of pulmonary disease highlights an overwhelming need in improving our understanding of lung development, disease, and treatment. It also calls for further advances in our ability to engineer the pulmonary system at cellular and tissue levels. The discovery of human pluripotent stem cells (hPSCs) offsets the relative inaccessibility of human lungs for studying developmental programs and disease mechanisms, all the while offering a potential source of cells and tissue for regenerative interventions. This review offers a perspective on where the lung stem cell field stands in terms of accomplishing these ambitious goals. We will trace the known stages and pathways involved in in vivo lung development and how they inspire the directed differentiation of stem and progenitor cells in vitro. We will also recap the efforts made to date to recapitulate the lung stem cell niche in vitro via engineered cell-cell and cell-extracellular matrix (ECM) interactions.

Spatiotemporal variability of drought/flood and its teleconnection with large-scale climate indices based on standard precipitation index: a case study of Taihu Basin, China.

With the intensification of global warming, frequency of floods and droughts has been increasing. Understanding their long-term characteristics and possible relationship with large-scale meteorological factors is essential. In this study, we apply signal denoising, dimensionality reduction technique, and wavelet transform to study the spatiotemporal distribution pattern of drought/flood and its teleconnection with large-scale climate indices. Based on the precipitation data of 63 hydrological stations in the Taihu Lake Basin (TLB) for 54 years from 1965 to 2018, the standard precipitation index (SPI) was used as an indicator. The ensemble empirical mode decomposition (EEMD) and empirical orthogonal function (EOF) methods were used to explore the spatiotemporal evolution characteristics of droughts and floods. In addition, the cross-wavelet transform (XWT) method was used for teleconnection analysis. The results indicated that during 1965-2018, the SPI of the TLB showed quasiperiodic oscillations dominated by interannual oscillations (52.5%). Except for the trend of drought in spring, the basin showed a wetter trend at annual, summer, autumn, and winter scales. There were two main spatial modes (total 78.48% contribution) in the TLB, consistent across the region and reverse distributed from south to north. The dry areas were mainly in southern Zhexi and the northern Huxi sub-regions; the Hangjiahu and Yangchengdianmao sub-regions were prone to flooding. In addition, SPI was correlated with various large-scale meteorological factors, but the strength of the correlation had specific temporal and spatial heterogeneity. The research results can provide TLB reference values for water resource management and flood/drought disaster control.

Gut microbiome diversity mediates the association between right dorsolateral prefrontal cortex and anxiety level.

Despite the fast growing interest in the impact of microbiome-gut-brain interaction on regulating emotional behavior in animals, the underlying mechanisms on how brain anatomy together with gut microbiotic condition jointly influence emotional state in healthy human volunteers remain largely unknown and hypothetic. Here, high-resolution structural magnetic resonance imaging data, stool samples, and psychological assessment results on anxiety level were collected from 61 healthy adults. Voxel-based morphometry was used to assess gray matter (GM) volumes, whereas 16s rRNA gene sequencing was used for bacterial classification. Correlation and mediation analysis were conducted to quantify the relationships among regional GM volume, gut microbiome diversity, and anxiety level. We observed that anxiety level was negatively correlated with GM volume in the right dorsolateral prefrontal cortex and alpha diversity index of gut microbiome. Additional mediation analysis revealed the indirect effect of dorsolateral prefrontal cortex GM volume on anxiety level via gut microbiome diversity. Our findings provide potential evidence of the microbiome-gut-brain interactions and their association with anxiety, highlighting gut microbiome diversity as a mediator that influences the relationship between brain morphometry and anxiety level.

Mapping the Heterogeneous Brain Structural Phenotype of Autism Spectrum Disorder Using the Normative Model.

BACKGROUND: Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by substantial clinical and biological heterogeneity. Quantitative and individualized metrics for delineating the heterogeneity of brain structure in ASD are still lacking. Likewise, the extent to which brain structural metrics of ASD deviate from typical development (TD) and whether deviations can be used for parsing brain structural phenotypes of ASD is unclear. METHODS: T1-weighted magnetic resonance imaging data from the Autism Brain Imaging Data Exchange (ABIDE) II (nTD = 564) were used to generate a normative model to map brain structure deviations of ABIDE I subjects (nTD = 560, nASD = 496). Voxel-based morphometry was used to compute gray matter volume. Non-negative matrix factorization was employed to decompose the gray matter matrix into 6 factors and weights. These weights were used for normative modeling to estimate the factor deviations. Then, clustering analysis was used to identify ASD subtypes. RESULTS: Compared with TD, ASD showed increased weights and deviations in 5 factors. Three subtypes with distinct neuroanatomical deviation patterns were identified. ASD subtype 1 and subtype 3 showed positive deviations, whereas ASD subtype 2 showed negative deviations. Distinct clinical manifestations in social communication deficits were identified among the three subtypes. CONCLUSIONS: Our findings suggest that individuals with ASD have heterogeneous deviation patterns in brain structure. The results highlight the need to test for subtypes in neuroimaging studies of ASD. This study also presents a framework for understanding neuroanatomical heterogeneity in this increasingly prevalent neurodevelopmental disorder.

Bioorthogonal Labeling and Chemoselective Functionalization of Lung Extracellular Matrix.

Decellularized extracellular matrix (ECM) biomaterials derived from native tissues and organs are widely used for tissue engineering and wound repair. To boost their regenerative potential, ECM biomaterials can be functionalized via the immobilization of bioactive molecules. To enable ECM functionalization in a chemoselective manner, we have recently reported an effective approach for labeling native organ ECM with the click chemistry-reactive azide ligand via physiologic post-translational glycosylation. Here, using the rat lung as a model, we provide a detailed protocol for in vivo and ex vivo metabolic azide labeling of the native organ ECM using N-Azidoacetylgalactosamine-tetraacylated (Ac4GalNAz), together with procedures for decellularization and labeling characterization. Our approach enables specific and robust ECM labeling within three days in vivo or within one day during ex vivo organ culture. The resulting ECM labeling remains stable following decellularization. With our approach, ECM biomaterials can be functionalized with desired alkyne-modified biomolecules, such as growth factors and glycosaminoglycans, for tissue engineering and regenerative applications.

Subcortical structural covariance in young children with autism spectrum disorder.

Abnormalities in the structure of subcortical regions are central to numerous behaviors affected by autism spectrum disorder (ASD), and these regions may undergo atypical coordinated neurodevelopment. However, relatively little is known about morphological correlations among subcortical structures in young children with ASD. In this study, using volumetric-based methodology and structural covariance approach, we investigated structural covariance of subcortical brain volume in 40 young children with ASD (<7.5 years old) and 38 age-, gender-, and handedness-matched typically developing (TD) children. Results showed that compared with TD children, children with ASD exhibited decreased structural covariation between the left and right cerebral hemispheres, specifically between the left and right thalami, right globus pallidus and left nucleus accumbens, and left globus pallidus and right nucleus accumbens. Compared with TD children, children with ASD exhibited increased structural covariation between adjacent regions, such as between the right globus pallidus and right putamen. Additionally, abnormalities in subcortical structural covariance can predict social communication and repetitive and stereotypic behavior in young children with ASD. Overall, these results suggest decreased long-range structural covariation and enhanced local covariation in subcortical structures in children with ASD, highlighting aberrant developmental coordination or synchronized maturation between subcortical regions that play crucial roles in social cognition and behavior in ASD.

Dact3 inhibits the malignant phenotype of non-small cell lung cancer through downregulation of c-Myb.

Dact3 is a negative regulator of Wnt/ß-catenin signaling. c-Myb promotes tumor cell invasion through Wnt/ß-catenin pathway. However, the detailed mechanism by which Dact3 and c-Myb modulate the progression of non-small cell lung cancer (NSCLC) remains unclear. In this study, the expressions of Dact3 and c-Myb in 254 surgically resected NSCLC samples were detected by immunohistochemistry. We transfected Dact3 cDNA to A549 and H157 cells or siRNA-Dact3 to SPC cells and examined above effects on the activity of Wnt/ß-catenin signaling by Western blot and luciferase activity assay, in addition to cell biological behavior by Transwell and MTT assay. Dact3 expression was reduced in NSCLC tissue. Reduced Dact3 expression was correlated with lymph node metastasis and poor prognosis of NSCLC (P<0.05). In addition, Dact3 expression was negatively correlated with the c-Myb expression (R = -0.626, P<0.05). Dact3 transfection resulted in c-Myb reduced expression in NSCLC cells, as well as decreased activity of Wnt/ß-catenin signaling and reduced cell invasive and proliferative capacity. siRNA-Dact3 transfection had the opposite effect. Our results indicate that Dact3 may inhibit the malignant phenotype of NSCLC through downregulation of c-Myb.