Figure 1.

Illustration of cell-technology classification in relation to potential therapeutic use. Key: long arrow towards the human body indicates an autologous approach; short arrows indicate the potential for allogeneic approaches; dashed arrow indicates combinatorial use of cells in 3D technologies; GM stands for gene modifications. The bubbles accompanying each classification graphically illustrate specific technology characteristics as follows: Ex vivo GM with viral vectors: a somatic cell and a generic lentivirus enclosing a vector containing a gene sequence of interest; Somatic cells: a flow cytometry diagram, a method often used to purify or characterize somatic cells prior to usage based on cell surface marker expression; In vivo GM with viral vectors: a generic adenovirus enclosing a vector containing a gene sequence of interest; 3D technologies: a trachea exemplifying a biological three-dimensional scaffold; Cell immortalization: a generic cell and the molecular structure of 4-hydroxytamoxifen, a compound used as an immortalization regulator; Genome editing: a scissor cutting a DNA strand; Cell plasticity: a pluripotent stem cell differentiation tree symbolizing cell plasticity.