Hydrogel particle encapsulated viable cells for in vivo regenerative treatment
A composition for tendon and ligament regeneration includes a biologically compatible hydrogel suspension having spherical droplets. The spherical droplets have a diameter of about 100 μm to about 300 μm and a plurality of cells. The cells include marrow-derived mesenchymal stem cells (MSCs) with an average viability of about 90% or greater and cells that retain their stemness. A method for tendon and ligament regeneration includes forming the composition, purifying the composition, retrieving the composition, and administering the composition via injection into an injury site of injured tissue.
1 . A hydrogel composition for orthopedic tissue rejuvenation, the hydrogel composition comprising:
a biologically compatible hydrogel suspension having hydrogel particles containing viable cells, wherein the hydrogel particles comprise:
a PEG norbornene-based hydrogel polymer;
the hydrogel polymer lacks cell-adhesive peptide groups; and
wherein the hydrogel particles comprise spherical droplets having a diameter of about 100 μm to about 300 μm;
wherein the hydrogel particles contain a total number of cells between about 15 cells to about 50 cells per hydrogel particle;
wherein the viable cells within the hydrogel particles comprise an average viability of about 90% or greater; and
wherein the biologically compatible suspension of hydrogel particles is devoid of suspension medium, such that the viable cells maintain viability of at least about 80% after 10 days and at least about 75% after two weeks.
2 . The composition of claim 1 , wherein the viable cells have an average viability of about 93% or greater.
3 . The composition of claim 1 , wherein the diameter of the spherical droplets is small enough to pass through a 16-gauge to a 21-gauge syringe typically used for orthopedic injection applications.
4 . The composition of claim 1 , wherein the viable cells are marrow-derived mesenchymal stem cells.
5 . The composition of claim 4 , wherein the marrow-derived mesenchymal stem cells retain stem-cell like properties within the hydrogel particles.
6 . The composition of claim 5 , wherein stem cell-specific markers CD29 and CD44 were expressed in the composition over at least a 14 day period, and CD45 was not expressed during the 14 day period, thereby indicating retainment of the stem-cell like properties over the 14 day period.