Somaiah, Chinnapaka2018-02-272023-10-192018-02-272023-10-192017ROLL NO. 11610624https://gyan.iitg.ac.in/handle/123456789/909Supervisor: Bithiah Grace JaganathanBone marrow niche is composed of cellular and non-cellular compartments. Cellular environment includes hematopoietic stem cells (HSCs), non-hematopoietic stem cells and their derivatives. HSCs maintain the blood cell development. HSCs fate is determined by endosteal niche made of osteoblasts and stromal cells, and sinusoidal niche made of endothelial cells. HSCs proliferation and differentiation is regulated by interaction between the cells directly or indirectly. Stromal cells, their derivatives and secretory factors like growth factors, cytokines regulate the stem cells present in the bone marrow. It is a highly regulated process, imbalance in regulation leads to pathological conditions. In addition, it is composed of network like structure known as extra cellular matrix (ECM) which is made of collagen, fibronectin and proteoglycans, also known to regulate the stem cell properties. Mesenchymal stem cells (MSCs) from the non-hematopoietic stem cell compartment known to regulate the HSCs maintenance, proliferation and differentiation. The MSCs have self-renewal capacity to produce same type of stem cells and undergo differentiation to give rise to specialized mature cells like adipocytes, osteocytes, and chondrocytes. MSCs have role in wound healing, immune suppression, immune modulation, and angiogenesis. MSCs were first isolated from the bone marrow and also isolated from the various other sources like cord blood, peripheral blood, adipose tissue, placenta, cartilage etc. MSCs can be identified by expression of cell surface markers CD73, CD90 and CD105 and they are negative for hematopoietic markers CD34, CD45 and CD14. MSCs can be used to treat diseases such as neurodegenerative diseases, heart diseases, leukemia, muscular dystrophy, bone diseases and diabetes.enBIOSCIENCES AND BIOENGINEERINGRole of cell extrinsic and intrinsic factors in regulating mesenchymal stem cell propertiesThesis