Transforming one organ into another to overcome challenges in tissue engineering

Tissue engineering (TE) is promising for the regeneration of failed organs. However, immune rejection, shortage of seed cells, and unintegrated blood vessels restrict the development and clinical application of TE. The last factor is the most challenging and intractable. Harnessing the mature blood vessel network in existing dispensable organs could be a powerful approach to effectively overcome the obstacles. After being remodeled to harbor an immunosuppressive and proregenerative niche, these potential target organs can be transformed into other organs with specific physiological functions, compensating the latter's failed native functions. Organ transformation, such as a hepatized spleen, represents an effective and encouraging TE strategy. In this review, we discuss the current development and obstacles of TE and its feasibility and superiority in organ transformation.