Comment on: Regenerative medicine, organ bioengineering and transplantation

Dear Editor,

We read with interest the review paper by Edgar et al.1 that discussed the application of regenerative medicine and bioengineering techniques to the medical field. Edgar et al. proposed their paper as a review highlighting actual regenerative medicine and bioengineering techniques applicable in clinical practice. However, we noted that authors considered regenerative medicine solely in the context of cells, scaffolds, and growth factors, without mentioning novel cell-free techniques including delivery of non-coding RNAs, cell-free conditioned medium, and gene therapy.