Professor Daniel Kelly holds the Chair of Tissue Engineering at Trinity College Dublin. He received his BAI degree (Baccalaureus in Arte Ingeniaria, Latin for Bachelor in the Art of Engineering) from Trinity College Dublin, and then completed an MSc and a PhD in the field of Biomedical Engineering. After working in the medical device industry, he joined the School of Engineering in Trinity College as a lecturer in 2005. In 2008 he was the recipient of a Science Foundation Ireland President of Ireland Young Researcher Award. In 2009 he received a Fulbright Award to take a position as a Visiting Research Scholar at the Department of Biomedical Engineering in Columbia University, New York. He is the recipient of four European Research Council awards (Starter grant 2010; Consolidator grant 2015; Proof of Concept grant 2017; Advanced grant 2021). He was elected a fellow of Trinity College Dublin in 2010 and was promoted to his current chair in 2017.

Prof. Kelly leads a multidisciplinary musculoskeletal tissue engineering group based in the Trinity Centre for Biomedical Engineering. The goal of his laboratory is to understand how environmental factors regulate the fate of adult stem cells. This research underpins a more translational programme aimed at developing novel tissue engineering and 3D bioprinting strategies to regenerate damaged and diseased musculoskeletal tissues. To date he has published over 180 articles in peer-reviewed journals and secured over €18 million in research funding. Throughout his academic career, Prof. Kelly has taught thousands of students on topics including solid mechanics, biomechanics, materials engineering and cell and tissue engineering. He has mentored 8 postdoctoral researchers and supervised 21 PhD students to completion; these lab alumni now work in industry and academia in the US, Africa, India and throughout Europe.

Prof. Kelly lives in Bray, Co. Wicklow with his wife Catherine and children Ben (14) and Sadhbh (12). In his spare time he enjoys playing golf and walking his dog along the seafront in Bray and along Mullaghmore beach.

Key Research Achievements

Bone and cartilage tissue engineering

My lab has demonstrated that adult stem cells isolated from synovial joints can be used to tissue engineer functional cartilage grafts (10.1089/ten.TEA.2011.0544), especially when combined with bioreactors to mechanically stimulate these cells (10.1016/j.jbiomech.2013.12.006). We have demonstrated that it is possible to engineer zonal tissues such as articular cartilage by recapitulating the gradients in regulatory signals that during development and skeletal maturation are believed to drive spatial changes in stem cell differentiation and tissue organization (10.1371/journal.pone.0060764). Realising this required undertaking a series of fundamental studies to understand how chondrogenesis, hypertrophy and endochondral ossification is regulated by altered levels of oxygen and mechanical cues. We have demonstrated how complex tissues, such as the bone-cartilage interface, can be regenerated by designing tissue engineering strategies that recapitulate aspects of the normal long bone developmental process (10.1016/j.actbio.2012.11.008). We have also shown that it is possible to scale-up such developmentally inspired processes to regenerate large bone defects (10.1016/j.biomaterials.2018.01.057), or tissue engineer entire new bones (10.1089/biores.2015.0014) or biological implants for whole joint resurfacing (10.22203/ecm.v030a12). To extend the utility of this strategy, we have used 3D bioprinting to engineer scaled-up hypertrophic cartilage templates for bone organ engineering (10.1002/adhm.201600182).

Single stage strategies for bone and cartilage repair

In 2010 I was awarded a European Research Council (ERC) starter grant to develop novel stem cell based therapies to regenerate damaged articular cartilage. To realise the goals of this project, we first developed a range of decellularized extracellular matrix (ECM) derived scaffolds for articular cartilage (10.1016/j.actbio.2014.05.030), bone (10.22203/eCM.v033a10) and osteochondral defect repair (10.1016/j.biomaterials.2018.09.044), and have tested these scaffolds in relevant pre-clinical animal models. We then developed a single-stage, cell based therapy for articular cartilage regeneration by combining these biomimetic scaffolds with freshly isolated stromal cells sourced from patients in-clinic (10.1002/adhm.201400687). We recently completed an ERC proof-of-concept based on outputs from this project and are exploring different options to commercialise and clinically translate this research.

3D bioprinting for the regeneration of musculoskeletal tissues

In recent years we have utilised emerging biofabrication and bioprinting strategies to engineer structurally organised articular cartilage (10.1016/j.biomaterials.2018.12.028). We have also developed a range of different bioinks capable of supporting distinct cellular phenotypes, and used these bioinks to bioprint cartilage (10.1002/adhm.201801501) and meniscal (10.1002/term.2602) grafts. As part of my recently completed ERC consolidator grant, we modified such inks to provide them with unique mechanical properties compatible with load bearing environments (10.1088/1758-5090/ab8708). Furthermore, we bioprinted implants containing spatiotemporally defined patterns of growth factors and demonstrated that printed constructs containing a gradient of VEGF, coupled with spatially defined BMP-2 localization and release kinetics, accelerated large bone defect healing with little heterotopic bone formation (10.1126/sciadv.abb5093). We have also used 3D printing techniques to produce fibre-reinforced cartilaginous templates, and assessed the efficacy of such constructs in a caprine model of osteochondral defect repair (10.1016/j.actbio.2020.05.040).