Zhuge, H. | Search bioRxiv

bioRxiv2024

In vitro spatiotemporal reconstruction of human skeletal muscle organogenesis

Spatiotemporal recapitulation of long-range trajectories for lineages that influence body patterning along the medio-lateral and proximal-distal axes during embryogenesis in an in vitro system remains elusive. Here we introduce a three-dimensional organoid approach, termed Gastruloids-Lateraloid-Musculoids (GLMs), to model human neural crest, lateral plate mesoderm and skeletal muscle lineage development at the forelimb level following gastrulation and during limb patterning. GLMs harvest neuro-mesodermal progenitors with the potential to establish neural and paraxial mesodermal populations, while single cell analyses and spatial transcriptomics demonstrate promotion of mesodermal lineage segregation during gastrulation and spatial recapitulation of migration events along the medio-lateral axis for vagal neural crest, hypaxial myogenesis and lateral plate mesodermal lineages. Comparative analyses to developmental atlases and adult muscle stem cell data confirm a pool of hypaxial migrating myogenic progenitors that in a niche dependent manner change their embryonic anatomical developmental program to a fetal myogenic program, thus enabling them to resist specification in a cell autonomous manner and facilitate long term in vitro expansion. GLMs model human myogenesis at the forelimb level, establish fetal muscle stem cells equivalent to those that sustain the growth phase of the embryo and provide a 3D in vitro system for investigating neural crest, early fore-gut and lateral plate mesoderm development.

developmental biology↗

bioRxiv2022

A Camera-Assisted Pathology Microscope to Capture the Lost Data in Clinical Glass Slide Diagnosis

Digital pathology, or the practice of acquiring, managing, and interpreting high-resolution digital images from glass pathology slides, holds much promise in precision medicine, potentially transforming diagnosis and prognosis based on computational image biomarkers derived from digital tissue images. However, for all its promise, digital imaging in pathology has not yet become an integral part of the clinical workflow as it has in radiology due to high cost, workflow disruptions, burdensome data sizes and IT requirements, and additional dedicated personnel requirements. Consequently, pathology retains the 150-year-old analog workflow, and the vast majority of slides used in clinical diagnosis are never digitized. Furthermore, there is a missed opportunity to capture the image information and associated data on search processes that led to the clinical diagnosis, which could serve as the foundation for computational clinical decision support. This paper describes an approach for slide digitization during clinical review using a camera attached to a standard brightfield pathology microscope. While a pathologist reviews a glass slide using the eyepiece oculars, the continuously running camera digitizes a complete record of the slide review, resulting in multi-resolution slide images and spatiotemporal saliency maps of the slide review. Unlike other approaches, the pathologist does not stop to review the video stream or monitor the acquisition of video frames but performs the diagnostic review at the microscope using the standard clinical protocol. This hybrid analog-digital approach combines the benefits of digital slide analysis, including annotation, computation, and the ability to confirm the completeness and quality of the glass slide review with the ease of using the microscope for primary diagnosis. Furthermore, a record of the pathologists attention during the review, including their search path, magnification level, and dwell times at each location on the slide, is obtained. In the future, this approach could enable the development and application of new and emerging computational decision-support algorithms in real-time to provide feedback to the pathologist, reduce diagnostic errors, and improve disease diagnosis and prognosis.

bioengineering↗