Cell migration plays a major role in physiological processes like inflammation, tumorigenesis as well as regeneration and repair. Chemotactic agents like growth factors, hormones and cytokines provide signalling clues for cells to home to specific sites. Morphogenetic processes observed during embryonic development are similar to regeneration of some adult human tissues, and therefore regeneration may be regarded as a recapitulation of embryonic processes. Developmental biology shows that a temporal and specific cascade of events is necessary for tissue formation. A specific microenvironment similar to that of a technically advanced bioreactor allows the formation of complex tissues. This novel concept of biological guidance is defined as 'a therapeutic approach for channelling specific biologic events by directing and orchestrating cellular mediators and factors in order to achieve in vivo tissue regeneration'. This aims to trigger in a temporal and special sequence specific events, which lead to a perpetual chain reaction ultimately resulting in the formation of complex tissues. Studies by the authors have shown that the lessons learnt from nuclear chain reactions can be applied to the formation of tissues in tissue engineering. Cells can be chemotactically directed to migrate into specific areas and are then triggered to perform a specific function. Ultimately for regenerative medicine and particularly tissue engineering, it is necessary to provide the overall framework (biomaterials) and signalling clues (bioactive factors) and critical mass (cells), which together then start the reaction in vivo. Only with the appropriate in vivo environment will the whole assemblage result in formation of tissues. If the appropriate environment is not present, scar or simple non-functional connective tissue formation will result. This chapter will give an overview regarding the principles of guidance, and explain how this concept will represent a paradigm shift, in regards to translating tissue engineering concepts from the laboratory to clinical application.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)