**5. Conclusions**

In this paper we report the generation of a novel type of bioprinted 3D neuronal construct, based on cortical neurons and glial cells derived from hiPSCs. The cortical construct develops molecular, morphological and functional properties of neuronal networks and can be used for future disease modeling studies as well as for drug screening.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2077-0383/8/10/1595/s1, Figure S1: The custom bioprinter used in this work, Figure S2: Neural differentiation of human iPSCs, Figure S3: Effects of the treatment with Alginate-lyase on the bioprinted specimen, Figure S4: Quantitative RT-PCR analysis, Figure S5: Assessment of the 2D conventional cultures functionality, Table S1: Primers used in this study, Video S1 and S2: 3D bioprinting.

**Author Contributions:** Conceptualization, F.S., C.C., S.D.A. and A.R.; Formal analysis, A.S., V.d.T., S.G. and M.R.; Investigation, F.S., C.C., C.B., A.S., V.d.T. and M.C.B.; Methodology, F.S., C.C. and C.B.; Project administration, S.D.A. and A.R.; Supervision, S.D.A. and A.R.; Writing – original draft, S.D.A. and A.R.

**Funding:** This research received no external funding.

**Acknowledgments:** The authors wish to thank the Imaging Facility at Center for Life Nano Science (CLNS), Istituto Italiano di Tecnologia, for support and technical advice. We are grateful to Giorgia Belloni for technical help in the qRT-PCR experiments of Figure S2 and Chiara Scognamiglio for advice on 3D bioprinting. We thank Giancarlo Ruocco and the other colleagues of CLNS for helpful discussion.

**Conflicts of Interest:** The authors declare no conflict of interest.
