Self Renewal

Embryonic (ES) and induced pluripotent (iPS) cells present an enormous potential as biological tools in strategies for regenerative medicine, drug discovery, disease models, as well as, for research in developmental biology. The ability of ES and iPS cells to proliferate indefinitely while maintaining the capacity to differentiate into many cell types distinguishes them from all other cells. However, it is precisely this characteristic that is the basis of their sensitivity to the environment. Stimuli from the extracellular surroundings, both physical and chemical, influence cell behavior by triggering cell signaling pathways that direct cells to remain in a pluripotent state or to differentiate into a mature cell type.

Due to the nature of pluripotent stem cells to differentiate upon changes to their environment, culturing ES and iPS cells in vitro has proven to be a major challenge. Providing a suitable and controllable milieu that allows these cells to be sustained in cultures over long periods of time is a primary objective of stem cell biologist.

A number of factors that should be considered for sustained culturing of ES and iPS stem cells include:

  1. Defined cell culture medium for reproducibility
  2. Defined media components at optimal concentrations; cytokines (growth factors) and small molecules
  3. Optimal cell density
  4. Methods for passaging cells that do not force differentiation
  5. Defined basement membrane substrates that facilitate cell attachment

Because of their extreme sensitivity, ES and iPS cell cultures should be routinely monitored for pluripotency.

Some of the key assays include:

  1. Normal colony morphology and rate of proliferation
  2. Expression of key pluripotency genes and absence of lineage-specific genes (for iPS cells)
  3. Expression of key pluripotency surface markers
  4. Ability to differentiate into cells from all three primary germline layer tissues in vivo and in vitro
  5. Normal genetic karyotype

With the increasing speed with which new technologies for stem cell research are being developed, our teams at Stemgent work diligently with our Scientific Advisory Board and other leading stem cell scientists to validate and deliver cutting-edge reagents that enable you to more readily culture and characterize ES and iPS cells for use in strategies in regenerative medicine, disease modeling, drug discovery, and developmental biology.