The use of microcarrier bioreactor technology to obtain a sufficient number of cells has
always been a research hotspot in the field of stem cells and regenerative medicine.
Microcarrier technology has many advantages over traditional flat cell culture methods,
such as the ability to increase cell growth in the short term, simplify complex and
cumbersome culture processes in the past, greatly save space and manpower, and
provide a more suitable microenvironment for cell growth to maintain cell phenotype
and function.
Microcarriers refer to microbeads with a specific diameter range that are suitable for the
growth of adherent cells. They provide a living space for cells to attach and suspend the
cell microcarriers by gently stirring the microcarrier culture medium. This culture method
is called microcarrier cell culture technology. In 1967, microcarriers were first developed
and applied in the cultivation of biological cells by Dutch scholar Van Wezel [1].
Microcarrier technology adopts a three-dimensional culture method, which can obtain a
large number of cells in a short period of time, and the cell passage process only
requires the addition of new microcarriers, eliminating the process of pancreatic enzyme
digestion in the past, greatly increasing the yield of cell culture in vitro. Compared to
traditional planar static culture, suspension culture of cell microcarriers has various
environmental parameters (pH, pO2, etc.) that are easier to monitor and control, and has
a larger specific surface area for stem cell adhesion and growth.
There are many types of materials used for micro loading preparation, mainly including
natural or synthetic biomaterials such as chitosan, alginate, collagen, gelatin, polylactic
acid (PLLA), polylactic acid polyglycolic acid copolymer (PLGA), and cellulose. These
materials have advantages such as good biocompatibility, non toxicity, low
immunogenicity, and controllable performance.
In addition to the composition of materials, the size, morphology, and surface topology
of microcarriers also have a significant impact on cell adhesion, proliferation, and
differentiation. Microcarriers with micropores or macropores can provide a better 3D
microenvironment for cells, providing more space for cell attachment and growth. At the
same time, chemical modification or modification can be applied to the surface of
microcarriers to increase cell adhesion and promote cell growth and differentiation.
Under the influence of fluid dynamics, the cells on the surface of microcarriers are
susceptible to factors such as shear forces and intercellular collisions. Porous
microcarriers not only provide more attachment space for cells, but also maximize the
protection of cells from these external factors.
Cell microcarriers prepared using biodegradable biomaterials can also serve as carriers
for cells and drugs to be delivered into the body, providing a novel therapeutic
approach for damaged tissues. Therefore, they have broad application prospects in stem
cell therapy and regenerative medicine fields such as tumors, chronic diseases, and
wound repair.
