Table 1 Critical Criteria for 3D printing

Cell source

● Inclusion of multiple cell types

Scaffold

● Biocompatible

● Mechanically biomimetic

○ Able to withstand fluid flow forces

● Safe

● Durable

○ Able to be handled and maintained in vitro and in vivo

Structure

● Multiscale

● Hierarchical

Functional

● Perfusion, filtration, secretion, absorption, and drainage of urine

● Maintenance of homeostasis

● Control of functions:

○ Hemodynamic

○ Immunological

○ Endocrine

Manufacturing process

● High-resolution cell deposition

● Controlled cell distribution

● Inclusion of:

○ Vascularisation

○ Innervation