Limits...
Controlled Delivery of Human Cells by Temperature Responsive Microcapsules.

Mak WC, Olesen K, Sivlér P, Lee CJ, Moreno-Jimenez I, Edin J, Courtman D, Skog M, Griffith M - J Funct Biomater (2015)

Bottom Line: However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into.Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line-human umbilical vein endothelial cells (HUVECs).While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

View Article: PubMed Central - PubMed

Affiliation: Integrative Regenerative Medicine Centre, Department of Clinical and Experimental Medicine, Linköping University, SE58185, Linköping, Sweden. mamak@ifm.liu.se.

ABSTRACT
Cell therapy is one of the most promising areas within regenerative medicine. However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into. Encapsulation of individual cells has been proposed as a means of increasing cell viability. In this study, we developed a facile, high throughput method for creating temperature responsive microcapsules comprising agarose, gelatin and fibrinogen for delivery and subsequent controlled release of cells. We verified the hypothesis that composite capsules combining agarose and gelatin, which possess different phase transition temperatures from solid to liquid, facilitated the destabilization of the capsules for cell release. Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line-human umbilical vein endothelial cells (HUVECs). While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

No MeSH data available.


Related in: MedlinePlus

Schematic diagram illustrating the high throughput preparation of cell microcapsules using the Nisco VAR J30 System.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493523&req=5

jfb-06-00439-f008: Schematic diagram illustrating the high throughput preparation of cell microcapsules using the Nisco VAR J30 System.

Mentions: For encapsulation, 2.0 × 106 to 8.0 × 106 cells were re-suspended in approximately 500 μL of medium, DMEM for fibroblast or M199 for HUVECs, then mixed with 500 μL of the encapsulation hydrogel, which comprised a mixture of 2% low-gelling temperature agarose, 1% gelatin and 10 mg·mL−1 fibrinogen in medium at 40 °C. Control experiments included encapsulation of cells in agarose only, and empty agarose–gelatin capsules. A diagram showing our cell encapsulation system is given in Figure 8. In brief, cell-hydrogel mixtures were loaded into a syringe and extruded through a regulated nozzle of 25 μm in diameter, warmed at constant temperature of 40 °C. The flow rate was controlled by use of a syringe pump that was set at a flow rate of 0.3 mL min−1 that created a spray of microdroplets. The air pressure was set at 350 mBar. The microdroplets were collected in an ice-cooled mineral oil bath containing 0.5% Span-80. The bath was stirred for 5 min allowing the solidification of the hydrogel droplets. The solution mixture containing encapsulated cells was then transferred to a 50 mL centrifugation tube. They were then washed by addition of 15 mL of medium followed by centrifugation at 350 r.c.f. at 4° for 10 min. The bottom, aqueous fraction containing the cell capsules was collected and transferred to a 15 mL centrifuge tube. The cell capsules were then washed another two times with medium followed by centrifugation (350 r.c.f., 10 min) at room temperature. Finally, the cell capsules were re-suspended in medium and filtered through a 100 μm cell strainer followed by a 40 μm cell strainer where the captured cells where used for further experiments.


Controlled Delivery of Human Cells by Temperature Responsive Microcapsules.

Mak WC, Olesen K, Sivlér P, Lee CJ, Moreno-Jimenez I, Edin J, Courtman D, Skog M, Griffith M - J Funct Biomater (2015)

Schematic diagram illustrating the high throughput preparation of cell microcapsules using the Nisco VAR J30 System.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493523&req=5

jfb-06-00439-f008: Schematic diagram illustrating the high throughput preparation of cell microcapsules using the Nisco VAR J30 System.
Mentions: For encapsulation, 2.0 × 106 to 8.0 × 106 cells were re-suspended in approximately 500 μL of medium, DMEM for fibroblast or M199 for HUVECs, then mixed with 500 μL of the encapsulation hydrogel, which comprised a mixture of 2% low-gelling temperature agarose, 1% gelatin and 10 mg·mL−1 fibrinogen in medium at 40 °C. Control experiments included encapsulation of cells in agarose only, and empty agarose–gelatin capsules. A diagram showing our cell encapsulation system is given in Figure 8. In brief, cell-hydrogel mixtures were loaded into a syringe and extruded through a regulated nozzle of 25 μm in diameter, warmed at constant temperature of 40 °C. The flow rate was controlled by use of a syringe pump that was set at a flow rate of 0.3 mL min−1 that created a spray of microdroplets. The air pressure was set at 350 mBar. The microdroplets were collected in an ice-cooled mineral oil bath containing 0.5% Span-80. The bath was stirred for 5 min allowing the solidification of the hydrogel droplets. The solution mixture containing encapsulated cells was then transferred to a 50 mL centrifugation tube. They were then washed by addition of 15 mL of medium followed by centrifugation at 350 r.c.f. at 4° for 10 min. The bottom, aqueous fraction containing the cell capsules was collected and transferred to a 15 mL centrifuge tube. The cell capsules were then washed another two times with medium followed by centrifugation (350 r.c.f., 10 min) at room temperature. Finally, the cell capsules were re-suspended in medium and filtered through a 100 μm cell strainer followed by a 40 μm cell strainer where the captured cells where used for further experiments.

Bottom Line: However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into.Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line-human umbilical vein endothelial cells (HUVECs).While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

View Article: PubMed Central - PubMed

Affiliation: Integrative Regenerative Medicine Centre, Department of Clinical and Experimental Medicine, Linköping University, SE58185, Linköping, Sweden. mamak@ifm.liu.se.

ABSTRACT
Cell therapy is one of the most promising areas within regenerative medicine. However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into. Encapsulation of individual cells has been proposed as a means of increasing cell viability. In this study, we developed a facile, high throughput method for creating temperature responsive microcapsules comprising agarose, gelatin and fibrinogen for delivery and subsequent controlled release of cells. We verified the hypothesis that composite capsules combining agarose and gelatin, which possess different phase transition temperatures from solid to liquid, facilitated the destabilization of the capsules for cell release. Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line-human umbilical vein endothelial cells (HUVECs). While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

No MeSH data available.


Related in: MedlinePlus