Skip to main content

Table 2 Overview of risk factors and risks associated with stem cell-based therapy

From: Risk factors in the development of stem cell therapy

  Risk factors or hazards Identified risks
Intrinsic factors - Origin of cells (e.g. autologous vs. allogenic, diseased vs. healthy donor/tissue) - Rejection of cells
Cell characteristics - Differentiation status - Disease susceptibility
  - Tumourigenic potential - Unwanted biological effect (e.g. in vivo differentiation in unwanted cell type)
  - Proliferation capacity - Toxicity
  - Life span - neoplasm formation (benign or malignant)
  - Long term viability  
  - Excretion patterns (e.g. growth factors, cytokines, chemokines)  
Extrinsic factors Manufacturing and handling - Lack of donor history - Disease transmission
  - Starting and raw materials - Reactivation of latent viruses
  - Plasma derived materials - Cell line contamination (e.g. with unwanted cells, growth media components, chemicals)
  - Contamination by adventitious agents (viral/bacterial/mycoplasma/fungi, prions, parasites) - Mix-up of autologous patient material
  - Cell handling procedures (e.g. procurement) - neoplasm formation (benign or malignant)
  - Culture duration  
  - Tumourigenic potential (e.g. culture induced transformation, incomplete removal of undifferentiated cells)  
  - Non cellular components  
  - Pooling of allogenic cell populations  
  - Conservation (e.g. cryopreservatives)  
  - Storage conditions (e.g. failure of traceability, human material labelling)  
  - Transport conditions  
Clinical characteristics - Therapeutic use (i.e. homologous or non-homologous) - Undesired immune response (e.g. GVHD)
  - Indication - Unintended physiological and anatomical consequences (e.g. arrhythmia)
  - Administration route - Engraftment at unwanted location
  - Initiation of immune responses - Toxicity
  - Use of immune supressives - Lack of efficacy
  - Exposure duration - neoplasm formation (benign or malignant)
  - Underlying disease  
  - Irreversibility of the treatment