Article
A 3D Bioprinted Human Meniscus Shape Enriched with
Mesenchymal Cells
Mihai Hurmuz
1,2
, Mihai Ionac
3
, Carmen Tatu
4,5
, Daniela Puscasiu
6
, Catalin Adrian Miu
1,2,
*, Sergiu Galatanu
7
and Fabian Tatu
1,2
Citation: Hurmuz, M.; Ionac, M.;
Tatu, C.; Puscasiu, D.; Miu, C.A.;
Galatanu, S.; Tatu, F. A 3D Bioprinted
Human Meniscus Shape Enriched
with Mesenchymal Cells. Appl. Sci.
2021, 11, 11733. https://doi.org/
10.3390/app112411733
Academic Editor: Claudio Belvedere
Received: 9 November 2021
Accepted: 6 December 2021
Published: 10 December 2021
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1
Department of Orthopaedics, Urology and Medical Imaging, “Victor Babes” University of Medicine and
Pharmacy Timisoara, 2A.Eftimie Murgu Sq., 300041 Timisoara, Romania; hurmuz.mihai@umft.ro (M.H.);
tatu.fabian@umft.ro (F.T.)
2
“Victor Popescu” Emergency Military Hospital Timisoara, 7 Gheorghe Lazar Str., 300080 Timisoara, Romania
3
2nd Department of Surgery, “Victor Babes” University of Medicine and Pharmacy Timisoara,
2A Eftimie Murgu Sq., 300041 Timisoara, Romania; mihai.ionac@umft.ro
4
Department of Functional Sciences, “Victor Babes” University of Medicine and Pharmacy Timisoara,
2A Eftimie Murgu Sq.,300041 Timisoara, Romania; carmen.tatu@umft.ro
5
Pius Brinzeu Emergency Clinical County Hospital Timisoara, OncoGen, 156 Liviu Rebreanu Str.,
300723 Timisoara, Romania
6
Department of Microscopic Morphology, “Victor Babes” University of Medicine and Pharmacy Timisoara,
2A Eftimie Murgu Sq., 300041 Timisoara, Romania; puscasiu.daniela@umft.ro
7
Department of Mechanics and Strength of Materials, University Politehnica Timi
s
,
oara, 1 Mihai Viteazul Blvd.,
300222 Timisoara, Romania; sergiu.galatanu@upt.ro
* Correspondence: miu.catalin@umft.ro
Abstract:
Background and objectives: Regenerative medicine, with its massive development over the
years, has the potential to solve some of the most problematic medical issues, such as functional organ
transplantation. The aim of this study was to create a human meniscal shape 3D-printed enriched
with human adipose-derived mesenchymal cells. Materials and Methods: Human infrapatellar
fat pad was harvested, and mesenchymal cells were isolated. The mesenchymal stem cells were
differentiated to the chondrocite lineage and a hydrogel (a nanofibrillar cellulose, sodium alginate,
D-mannitol, and Hepes buffer solution combination) cell mixture was bioprinted to create three
human-size meniscus structures. The obtained structures were evaluated regarding the cell viability,
appropriate size in relation to a native meniscus, and some mechanical characteristics. Results:
The human meniscal shape created respected the anatomic characteristic of a native structure. Cell
viability of approximately 97% and extracellular matrix formation after the printing process were
observed. The mean maximum force for the meniscus with mesenchymal cells was 6.5 N (+/
−
0.5 N)
compared to the mean maximum force for the native meniscus of 10.32 N (+/
−
0.7 N), which is
statistically relevant (p < 0.01). Conclusion: This paper presents the potential of bioprinting viable
cell structures that could in the future present enough mechanical strength to replace a human organ,
such as a meniscus. There are still limitations regarding the ink and the printing process, but we are
confident that these problems will soon be solvable.
Keywords: bioprinting; biomeniscus; hydrogel; regenerative medicine
1. Introduction
Menisci are important structures in the biomechanical activity of the knee joints. In
many cases, due to trauma or simply through degenerative changes, the meniscus is torn
and acts as a destructive force over the cartilage covering the articular surfaces of the
knee [
1
]. Treatment mostly consists of meniscectomy of the torn portion, but in order to
preserve the normal function of the joint, an intact meniscus is needed [
2
]. The idea of
a meniscal transplant has long been proposed, but a mechanical and biological identical
structure has not yet been created [3].
Appl. Sci. 2021, 11, 11733. https://doi.org/10.3390/app112411733 https://www.mdpi.com/journal/applsci
