Cell density, dimethylsulfoxide concentration and needle gauge affect hydrogel-induced bone marrow mesenchymal stromal cell viability

Abstract

Mesenchymal stromal cells (MSCs) have shown potential therapeutic benefits for a range of medical disorders and maintain a focus of intense scientific investigation. Transplantation of MSCs into injured tissue can improve wound healing, tissue regeneration and functional recovery. However, implanted cells rapidly lose their viability or fail to integrate into host tissue. Hydrogel-seeded BM-MSCs offer improved viability in response to mechanical forces caused by syringe needles, cell density and dimethylsulfoxide (DMSO) concentration, which in turn, will help to clarify which factors are important for enhancing biomaterial-induced cell transplantation efficiency and provide much needed guidance for clinical trials. In this study, under the control of cell density (lower than 2×107 cells/ml) and final DMSO concentration (lower than 0.5%), hydrogel-induced BM-MSC viability remained over 82% following syringe needle passage by 25 or 27 gauge needles, providing improved cell therapeutic approaches for regenerative medicine.

Non‐Newtonian Polymer–Nanoparticle Hydrogels Enhance Cell Viability during Injection

“…Technology development is needed to enhance the delivery, protection, and encapsulation of cells to increase the viability and local retention of cells when injected. Previous works have shown that hydrogels are promising alternatives to PBS for administration of cell therapies, as they enhance local retention and improve the viability of cells during injection when compared to injections performed in PBS . It has been proposed that hydrogel “plug flow,” a phenomena caused by the rheology of these materials, protects the cells from the shear and extensional forces during injection from a syringe and needle .…”

“…Previous works have shown that hydrogels are promising alternatives to PBS for administration of cell therapies, as they enhance local retention and improve the viability of cells during injection when compared to injections performed in PBS. [10][11][12][13][14][15][16][17][18][19][20][21][22] It has been proposed that hydrogel "plug flow," a phenomena caused by the rheology of these materials, protects the cells from the shear and extensional forces during injection from a syringe and needle. [11] Hydrogels may also be used to provide an ECM mimic to enhance cell growth and differentiation.…”

Chitosan Microbeads Produced by One-Step Scalable Stirred Emulsification: A Promising Process for Cell Therapy Applications

“…The optimum needle size for cell therapy varies depending on the application and injection site. While 25G and 27G needles are the most commonly used clinically, for instance in cardiovascular interventions, 38,39 larger diameter needles such as 22G and 23G are also used in many applications such as intra-articular delivery. 40,41 In addition, it is possible to further decrease the diameter of the microbeads.…”

“…The optimum needle size for cell therapy varies depending on the application and injection site. While 25G and 27G needles are the most commonly used clinically, for instance in cardiovascular interventions, , larger diameter needles such as 22G and 23G are also used in many applications such as intra-articular delivery. , In addition, it is possible to further decrease the diameter of the microbeads. In contrast to conventional methods, where changes in the nozzle diameter and process parameters would be required to achieve different microbead sizes, the emulsion process enables control of the average bead diameter by simply adjusting the stirring speed .…”

Hydrogel Encapsulation: Taking the Therapy of Mesenchymal Stem Cells and Their Derived Secretome to the Next Level

“…Chen et al proposed hydrogel-induced BM-MSCs under conditions of cell density (<2 × 10 7 cells/mL), DMSO concentration (<0.5%), and needle gauge (25G or 27G). The survival rate could be maintained above 82% (Chen et al, 2017). Osama et al proposed a different view: MSCs injected with a 30G needle showed significantly better viability when the hydrogel was in the pre-and post-gel state (Osama et al, 2018).…”