A 3D engineered scaffold for hematopoietic progenitor/stem cell co-culture in vitro

Dezhi Zhou,Lidan Chen,Xiuxiu Zhang,Jinju Ding,Bin Yang,Tao Xu,Zhenguo Nie,Xinda Li

doi:10.1038/s41598-020-68250-5

Abstract

Proliferation of HPSCs in vitro can promote its broad clinical therapeutic use. For in vitro co-culture, interaction between the stem cell and feeder cell as well as their spatial position are essential. To imitate the natural microenvironment, a 3D engineered scaffold for CD34+ cells co-culture was established via 3D bioprinting. Herein, the concentration of hydrogel and the ratio of two kinds of cells were optimized. Flow cytometry, real time PCR and RNA-seq technology were applied to analyze the effect of the engineered scaffold on expanded cells. After 10 days co-culture with the engineered scaffold, the expansion of CD34+CD38− cells can reach 33.57-folds and the expansion of CD34+CD184+ cells can reach 16.66-folds. Result of PCR and RNA-seq indicates that the CD34+ cells in 3D group exhibited a tendency of interaction with the engineered scaffold. Compared to 2D co-culture, this customizable 3D engineered scaffold can provide an original and integrated environment for HPSCs growth. Additionally, this scaffold can be modified for different cell co-culture or cell behavior study.

Highlights

Proliferation of hematopoietic progenitor or stem cells (HPSCs) in vitro can promote its broad clinical therapeutic use
In Raic’s study, a porous polyethylene glycol (PEG) hydrogel scaffold was fabricated for 3D co-culture of HPSCs and mesenchymal stem cells (MSCs), but the cells were seeded on the surface of scaffold with a top-down s trategy[16]
The hydrogel scaffold produced here possessed a porous structure with micron-sized precision as well as a desirable stability that could maintain its shape after 14 days (Fig. 2A)

Summary

Introduction

Proliferation of HPSCs in vitro can promote its broad clinical therapeutic use. For in vitro co-culture, interaction between the stem cell and feeder cell as well as their spatial position are essential. To imitate the natural microenvironment, a 3D engineered scaffold for CD34+ cells co-culture was established via 3D bioprinting. Excessive irradiation can cause death or mutation of the feeder cells To solve this problem, a strategy that used hydrogel to encapsulate the MSCs. within beads to restrain their proliferation was developed to support HPSCs expansion 22,23. We firstly applied the cell printing technology to construct the cell-laden hydrogel as a 3D structure and subsequently CD34+ cells were seeded into the 3D scaffold (Fig. 1A–D) Within this 3D co-culture environment, the feeder cell (UC-MSC) maintain function in the hydrogel and secrete the effective growth factors which passes through the hydrogel to support the C D34+ cells culture (Fig. 1E). The effect of the engineered scaffold on C D34+ cells was analyzed and assessed

Results

Discussion

Conclusion