Human Amniotic Fluid Stem Cells: General Characteristics and Potential Therapeutic Applications

Amniotic fluid contains a mixture of different cell types sloughed from the fetal skin, respiratory, alimentary and urogenital tracts, as well as the amnion membrane. As amniotic fluid develops prior to the process of gastrulation, many cells found in its heterogeneous population do not undergo lineage specialization. Therefore, amniotic fluid-derived mesenchymal stem cells (AF-MSCs) may correspond to a new class of stem cells with properties of intermediate plasticity between pluripotent and adult stem cell types. Compared to mesenchymal stem cells (MSCs) from other sources, such as bone marrow, AF-MSCs have better properties for clinical applications, such as differentiation into the cells of three germ layers, high clonal capacity, ability to form embryoid bodies, expression of pluripotent markers, high self-renewal capacity (over 250 population doublings) with normal karyotype at late passages, long telomere length due to continued telomerase activity, specially non-tumorigenicity, low immunogenicity, anti-inflammatory and immunomodulatory properties.

Such features have nominated AF-MSC for a range of clinical applications, including in regenerative medicine. In several studies, these cells have been used to regenerate nerve, lung, and heart tissues. Overall, AF-MSCs are expected to be an ideal source of stem cells for future regenerative medicine and tissue engineering.