Vascularisation in regenerative therapeutics and surgery.

Vascularisation is often deemed the holy grail of tissue engineering because it is one of the key preconditions that determine the in vivo viability of tissue constructs. Given that a well-developed vascular network allows greater complexity in tissue design and helps regulate tissue metabolism, it appears that the overall outcome of engineered tissue implants depends on the success of microvessel formation, maturation and patterning. Current approaches to vascularising tissue include both in vivo and ex vivo techniques, where blood vessel formation is either spontaneous or guided by physical or biochemical factors. The success of these strategies can then be monitored and evaluated for clinical benefit through numerous standard and novel strategies. Despite the impressive progress in the field of tissue engineering in recent times, there are still numerous technical, immunological, surgical and ethical challenges to overcome. Future prospects in this field are likely to depend on the adoption of a wide-ranging approach incorporating a combination of salient themes such as genetic manipulation, modular assembly and bioreactor coupling. Where applicable, the potential contributions of nanobiotechnology to tissue vascularisation will be discussed as appropriate.