As human cell and tissue based products and therapies(HCT/Ps) become more prevalent in the healthcare industry, it is becoming increasingly important to properly understand the methods by which HCT/Ps repair tissue and provide therapeutic benefit.

The amniotic fetal membrane has attracted much attention as a possible source of cells in cell therapy over the past several years. The mesenchymal layer of the membrane contains human amniotic mesenchymal stromal cells(hAMSCs), which can be isolated from the amnion itself and cultured in solution [1]. Post-natal cells such as these are easily cultured and expanded, without ethical concerns, with high differentiation potential, and without risk of teratoma formation [2]. Mesenchymal stromal cells(MSCs) are often used in orthopedic therapies to regenerate cartilage and chondrocytes [3], as well as bone and tendon tissue [4], among various other applications. Once the cells have been sufficiently cultured in solution, they are cryopreserved and banked. In order to preserve cell viability and prevent freezing-induced cell damage, various cryopreservative agents are used, and cryopreservation protocols are used to limit the rate of freezing and thawing [5].

However, this procedure comes from a misunderstanding of the mechanism behind the therapeutic action of MSCs. In many cases, transplanted MSCs do not demonstrate a high survivability rate, and the rate of transdifferentiation of MSCs into surrounding tissue cell types has also been quite low, however, the expected therapeutic effects of MSC treatment are still observed in those studies [6-9]. It has now been shown that the principle mechanism that contributes to tissue repair are the secretion of soluble factors into surrounding media that act in a paracrine fashion [9]. The observed effects of MSC-related paracrine activity include anti-inflammatory immunosuppression, and the activation of resident stem cells in the area of interest [7-9]. The paracrine factors affect multiple cell types and create a microenvironment that promotes repair and regeneration at multiple time points [9]. In fact, MSC conditioned medium alone has been shown to be sufficient in replicating the therapeutic beneficial effects of cells of the same type [8,9]

Axolotl Biologix currently has a HCT/P available, AxoBioFluid, which is a amnion-derived mesenchymal stromal cell conditioned medium. As the isolated hAMSCs are cultured, the paracrine factors associated with MSC therapies accumulate in the growth medium [8,9], which is then packaged for use as per necessary dosage and cryopreserved in storage. Cryopreservative agents are not added to the serum-free, xeno-free, DMSO-free growth media.

 

  1. Magatti, Marta, et al. "Isolation, Culture, and Phenotypic Characterization of Mesenchymal Stromal Cells from the Amniotic Membrane of the Human Term Placenta." Mesenchymal Stem Cells: Methods and Protocols (2016): 233-244.

  2. Pozzobon, Michela, Martina Piccoli, and Paolo De Coppi. "Sources of mesenchymal stem cells: current and future clinical use." Mesenchymal Stem Cells-Basics and Clinical Application II. Springer Berlin Heidelberg, 2012. 267-286.

  3. Doran, Michael R., and Mark Young. "Mesenchymal Stromal Cells and the Repair of Cartilage Tissue." Mesenchymal Stem Cell Therapy. Humana Press, 2013. 145-160.

  4. Young, Mark, and Michael R. Doran. "Mesenchymal Stem Cell Therapies for Bone and Tendon Conditions." Mesenchymal Stem Cell Therapy. Humana Press, 2013. 117-144.

  5. Haack-Sørensen, Mandana, Annette Ekblond, and Jens Kastrup. "Cryopreservation and Revival of Human Mesenchymal Stromal Cells." Mesenchymal Stem Cells: Methods and Protocols (2016): 357-374.

  6. T. Wu, Y. Liu, B. Wang, and G. Li, “The roles of mesenchymal stem cells in tissue repair and disease modification,” Current Stem Cell Research and Therapy, vol. 9, no. 5, pp. 424–431, 2014.

  7. X. Liang, Y. Ding, Y. Zhang, H.-F. Tse, and Q. Lian, “Paracrine mechanisms of mesenchymal stem cell-based therapy: current status and perspectives,” Cell Transplantation, vol. 23, no. 9, pp. 1045–1059, 2014.

  8. Hodgkinson, Conrad P., et al. "Emerging concepts in paracrine mechanisms in regenerative cardiovascular medicine and biology." Circulation research 118.1 (2016): 95-107.

  9. M. Gnecchi, P. Danieli, G. Malpasso, and M. C. Ciuffreda, “Paracrine mechanisms of mesenchymal stem cells in tissue repair,” in Mesenchymal Stem Cells: Methods and Protocols, M. Gnecchi, Ed., vol. 1416 of Methods in Molecular Biology, pp. 123–146, Springer, Berlin, Germany, 2016.