The Institute for Development of Advanced Applied Systems (IRNAS), located in Slovenia, operates Symbiolab, an open source-based biolab that focuses on the development of future-proof 3D biofabrication. The company developed Vitaprint, an open source platform which has now been used by IRNAS to fabricate 3D Printed Blood Vessels into a human earlobe using the freeform perfusable vessel and channel systems into bio-compatible hydrogels.
Source: http://irnas.eu/bio-lab-symbiolab/2017/11/29/making-earlobe-shaped-channels-using-vitaprint