A new and exciting application is the encapsulation of allogenic stem cells. Here Cell-in-a-Box® helps localize the transplanted stem cells once implanted into the patient. Instead of being able to wander off, encapsulated cells are now fixed at the desired location because of the relatively large size of the capsules. This allows the cells to act at the chosen site of implantation for longer periods in time, in turn meaning that far fewer cells in total need to be implanted to have the same action.
Of course, the capsules also protect the stem cells from any attack from the patient's immune cells. Although not all stem cells are immunogenic, after a period of time there is likely to be interactions with the patient's cells which cause changes to the implanted cells and potentially their clearance.
Due to the porous nature of the capsule outer-wall, which allows nutrients and well as cellular signalling factors to go in as well as therapeutic factors to come out of the capsules, the necessary interactions with the implantation site (e.g. wound factor signalling) can still take place, but the cells themselves cannot be cleared allowing longer lasting therapeutic activity.
Finally, capsules can be removed after treatment is complete, a consideration which makes them especially attractive to the patient and authorities alike as well as making multiple rounds of treatment more viable if necessary.
To demonstrate the use of Cell-in-a-Box® technology, we have for instance shown that encapsulated stem cells survive well and grow in the capsules, whilst not losing their "stemness".
Advantages of encapsulating stem cells before application in patients include:
- Cells become physically constrained at the site of implantation, thus concentrating the effect of secreted factors
- Allogenic or even xenogenic cells are immunoprotected
- Stem cells are constrained in capsules so coulf be removed if necessary
- Thus lower doses are required giving increased efficacy