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Yogambha Ramaswamy, Khoon S Lim, Hala Zreiqat and Zufu Lu

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/63357

#### **Abstract**

Stem cells play a critical role in tissue regeneration and repair, maintenance and turnover and the control of haematopoiesis in the various tissues. These cells have an incredible ability to differentiate into specific cell types like osteoblasts, chondrocytes or myocytes and to develop bone, cartilage or muscle tissues. Now it is believed that the cells do not differentiate by themselves but rather the secretion of the bioactive (trophic) factors which are responsible for the functional outcome of the tissue. Stem cells reside in complicated and dynamic three-dimensional (3D) microenvironments in vivo known as stem cell niches. The niches are composed of extracellular matrix (ECM), soluble and tethered proteins and supporting cells, which have a profound influence on the functionality of the cells, including differentiation and trophic factor release. In this chapter, we review and emphasize the influence of stem cell microenvironment on the secretion of trophic factors and their perspective application for bone regeneration.

**Keywords:** bone, stem cells, tissue regeneration, niche, trophic factors
