The musculoskeletal system accounts for over one-third of adult body mass, is essential for locomotion, fine motor control and independence, yet it is currently underrepresented in the Human Cell Atlas. It is composed of a diverse array of tissues including the bony skeleton of the spine and limbs, plus their associated muscular systems, alongside the joint organs that contain cartilage, synovium, capsule, ligaments and tendons. Given the ubiquity of musculoskeletal tissue, it is unsurprising that musculoskeletal disease and traumatic injury are a leading global cause of years lived with significant disability, with low-income countries currently experiencing a disproportionate increase in disease burden.

Delivery of a cellular ‘road-map’ of ancestrally inclusive healthy musculoskeletal tissues will provide fundamental metrics to define the diverse tissues of the musculoskeletal system. This generational resource will pave the way for a cellular evaluation of therapeutic strategies and, when combined with future musculoskeletal disease datasets, accelerate our understanding of disease pathogenesis and revolutionize novel therapeutic identification. However, such an endeavor must ensure that the atlases generated are representative of global populations. Significant ethno-epidemiological variations are observed across almost every musculoskeletal tissue and disease. The curation of ancestrally diverse musculoskeletal atlases will ensure that future advances are equitably distributed and ethnically appropriate.

This international project aims to deliver an ancestrally-inclusive single-cell resolution atlas of the healthy adult musculoskeletal system. Atlas generation will be accompanied by development of resources for sustainable, continued, mapping of musculoskeletal tissues by global teams and local communities who are currently under-represented in biomedical science.

Year 1 Milestones:
Initiate tissue collection in India, Oman, Argentina, UK, Turkey and Zimbabwe
Pilot single nuclei RNAseq in Zimbabwe
Initiate adaptation of next generation sequencing analysis training
Initiate cellular annotation experiments (single cell RNAseq, combined snRNAseq and ATACseq) Compare tissue collection and storage methodologies

Deliverables: Optimized protocols and computational workflows for storage and sequencing of all musculoskeletal tissues
Active ethical approvals and tissue collections in India, Oman, Argentina, UK, Turkey and Zimbabwe

Year 2 Milestones:
Initiate active ethics and tissue collections in The Gambia
Initiate single nuclei sequencing of tissues from all sites
Deliver an adapted training programme on next generation sequencing analysis to new MSc cohort at the African Institute and Biomedical Science and Technology (AIBST) Pilot spatial mapping of musculoskeletal tissues
Implement survey of global orthopaedic researchers and clinicians to establish clinical, ethical and infrastructure barriers to musculoskeletal sequencing projects
Training of all network sites on tissue collections, tissue processing and where facilities exist, library preparation
Work with communities through CAGs to establish dialogue and understand perspectives. Community sensitization.

Deliverables: Optimized cellular annotation for musculoskeletal tissues
Early signatures, n=34 samples total comprising n=2 samples each of; capsule, bone, tendon, muscle from India, Zimbabwe and Turkey; bone and capsule from Oman and Argentina; tendon from The Gambia, to inform spatial mapping
Cohort of trained computational biologists in Zimbabwe engaged in analysis of network datasets Identified barriers and guidelines for global implementation of musculoskeletal atlasing studies.

Year 3 Milestones:

Complete stakeholder mapping exercise. Define communities for engagement and involvement and form Community Advisory Groups (CAGs) Complete spatial mapping and single nuclei sequencing Integration and comparison of imaging and sequencing datasets
Dissemination of findings to communities and stakeholders. Create MESH webspace.

Deliverables: Completed computational training for all network teams
Spatially resolved comparative single nuclei maps of ancestrally diverse musculoskeletal tissues (n=102 donors in total comprising n=6 capsule, bone, tendon and muscle from Zimbabwe, India and Turkey; n=6 bone and capsule from Oman and Argentina; n=6 tendon from The Gambia)
A biobank of adult musculoskeletal tissues for future analysis by the community resources for sustainable, continued, mapping of musculoskeletal tissues by global teams and local communities who are currently under-represented in biomedical science.