A novel core–shell microcapsule for encapsulation and 3D culture of embryonic stem cells

Abstract

In this study, we report the preparation of a novel microcapsule of ~ 100 μm with a liquid (as compared to solid-like alginate hydrogel) core and an alginate-chitosan-alginate (ACA) shell for encapsulation and culture of embryonic stem (ES) cells in the miniaturized 3D space of the liquid core. Murine R1 ES cells cultured in the microcapsules were found to survive (> 90%) well and proliferate to form either a single aggregate of pluripotent cells or embryoid body (EB) of more differentiated cells in each microcapsule within 7 days, dependent on the culture medium used. This novel microcapsule technology allows massive production of the cell aggregates or EBs of uniform size and controllable pluripotency, which is important for the practical application of stem cell based therapy. Moreover, the semipermeable ACA shell was found to significantly reduce immunoglobulin G (IgG) binding to the encapsulated cells by up to 8.2 times, compared to non-encapsulated cardiac fibroblasts, mesenchymal stem cells, and ES cells. This reduction should minimize inflammatory and immune responses induced damage to the cells implanted in vivo becasue IgG binding is an important first step of the undesired host responses. Therefore, the ACA microcapsule with selective shell permeability should be of importance to advance the emerging cell-based medicine.

Advances in multicellular spheroids formation

“…In the porous micro droplets, oxygen and nutrients were diffused in and metabolic waste diffused out to maximize the cell viability [124]. In addition, when the formed MCSs encapsulated inside the hydrogel droplets are injected into the patient's body, they are protected from host immune responses, which minimizes administration of immunosuppressive drugs and increases the successful transplantation rate [125]. This approach also has a high degree of control over the morphological and physical properties [109].…”

Electrospinning pectin-based nanofibers: a parametric and cross-linker study

“…The Ca 2+ treatment generated a more positive surface, but the overall charge was still negative. This is most likely due to the free carboxyl groups of pectin (Zhang et al 2013). A positive surface was generated when treated with oligochitosan because of the free amine groups.…”

“…Oligochitosan and pectin have complementary charges leading to the formation of polyelectrolytes. Additionally, oligochitosan can potentially generate a positive surface charge of the nanofibers, due to its protonated amino groups (Zhang et al 2013). This is critical for tissue engineering applications, since a positively charged surface is preferred for cell adhesion (Ko et al 2015;Suga et al 2015;Zhang et al 2017).…”

Alginate core-shell beads for simplified three-dimensional tumor spheroid culture and drug screening

“…Core-shell beads have also been reported for applications in forming tumor spheroids , embryoid bodies (Kim et al 2011), encapsulating islets (Ma et al 2013) or embryonic stem cells (Zhang et al 2013). Ma et al generated core-shell structures in two steps through co-axial electro-jetting (Ma et al 2013) while Kim et al used a one-step three-dimensional microfluidic focusing device (Kim et al 2011).…”