Development of a three-dimensional haematopoietic stem cell-permissive bone marrow niche model using magnetic levitation

QH301 Biology

Lewis, Natasha Shanti ; Berry, Catherine

University:University of Glasgow

Department:Institute of Molecular Cell and Systems Biology

关键词: Haemtopoietic stem cell, mesenchymal stem cell, bone marrow, nanoparticles, spheroids, tissue engineering, extracellular matrix, three dimensional culture.;   

Others  :  http://theses.gla.ac.uk/8989/7/2018LewisPhD.pdf

来源: University of Glasgow

【 摘 要 】

Haematopoietic stem cells (HSCs) have a huge clinical relevance as they are regularly used in bone marrow transplants worldwide. This therapy has profound potential to alleviate diseases of the blood and immune system, where others are ineffective. However, HSCs cannot currently be cultured long term ex vivo, as they rapidly differentiate or senesce. Hence, genetically matched donors must often be found for transplant and studies of HSCs require costly animal models.Mimicking the microenvironment of the bone marrow, in which they reside, by incorporating supportive stromal cells including mesenchymal stem cells (MSCs), has the potential to overcome these limitations. This project aimed to create an HSC-permissive MSC spheroid culture system using magnetic nanoparticles and a collagen gel. An existing spheroid system was optimised for HSC-MSC co-culture and then characterised to assess the potential for HSC support. MSC spheroids were more quiescent, and expressed higher levels of HSC-supportive genes such as nestin and CXCL12.Subsequently, additional bone marrow cell types were introduced to the model to mimic vascular and endosteal areas of the bone marrow niche. HSC behaviour within these models was investigated. MSCs, endothelial cells, and osteoblasts exhibited gene expression changes in line with those predicted from examination of the physiology of endosteal and vascular regions of the bone marrow: i.e. higher activity at the vascular niche (model including endothelial cells), and lower activity at the endosteum (model including osteoblasts). However, gene transcription and phenotypic analyses of HSCs following culture within the bone marrow models produced more inconclusive results. Hence, further optimisation of the conditions of the model and repetition of results presented here are required to develop the system so that it truly mimics physiological bone marrow.The development of such a model has many applications, including in drug discovery, modelling disease states, and probing haematopoietic functions.