Biological characterization of human amniotic epithelial cells in a serum-free system and their safety evaluation

Abstract

Human amniotic epithelial cells (hAECs), derived from the innermost layer of the term placenta closest to the fetus, have been shown to be potential seed cells for allogeneic cell therapy. Previous studies have shown a certain therapeutic effect of hAECs. However, no appropriate isolation and culture system for hAECs has been developed for clinical applications. In the present study, we established a serum-free protocol for hAEC isolation and cultivation, in which better cell growth was observed compared with that in a traditional culture system with serum. In addition to specific expression of cell surface markers (CD29, CD166 and CD90), characterization of the biological features of hAECs revealed expression of the pluripotent markers SSEA4, OCT4 and NANOG, which was greater than that in human mesenchymal stem cells, whereas very low levels of HLA-DR and HLA-DQ were detected, suggesting the weak immunogenicity of hAECs. Intriguingly, CD90+ hAECs were identified as a unique population with a powerful immunoregulatory capacity. In a systemic safety evaluation, intravenous administration of hAEC did not result in hemolytic, allergy, toxicity issues or, more importantly, tumorigenicity. Finally, the therapeutic effect of hAECs was demonstrated in mice with radiation-induced damage. The results revealed a novel function of hAECs in systemic injury recovery. Therefore, the current study provides an applicable and safe strategy for hAEC cell therapy administration in the clinical setting.

Human Amniotic Epithelial Stem Cells: A Promising Seed Cell for Clinical Applications

“…Besides the consideration of animal serum-derived contamination, our previous work also confirmed that neither acute nor long-term toxicity response is triggered by hAESC injection in xenogeneic transplantation [ 29 ]. Specifically, little change in T cell population and corelated cytokines is observed after high-dose (10 8 cells/kg) hAESC injection into mice, indicating that hAESCs do not disturb the immune system.…”

“…However, serious concern has been raised about the utilization of animal serum in clinical applications. To establish a more effective protocol for hAESC culture in accordance with current guidelines for clinical use, our lab developed a serum-free system for hAESC isolation and culture [ 29 ]. In brief, hAESCs are cultured with complete culture medium containing F12/DMEM, 10% KSR (KnockOut Serum Replacement), 2 mmol/L L-glutamine, 1% nonessential amino acids, 55 μmol/L 2-mer-captoethanol, 1 mmol/L sodium pyruvate, 1% antibiotic–antimycotic, and 10 ng/mL EGF.…”

Single-cell characterization and metabolic profiling of in vitro cultured human skeletal progenitors with enhanced in vivo bone forming capacity

“…Instead, serum-free culture systems were recently reported to stabilize the quality and the purity of the cell population. 17 As an outcome, these features can improve reliability, reproducibility, and robustness of the manufacturing process and be more predictive of the in vivo outcome.…”

“…Indeed, the use of platelet lysate or serum may have a proliferative effect, but involves an uncontrolled cocktail of factors introducing issues with repeatability, potency, and control of the process. Instead, serum‐free culture systems were recently reported to stabilize the quality and the purity of the cell population . As an outcome, these features can improve reliability, reproducibility, and robustness of the manufacturing process and be more predictive of the in vivo outcome.…”

Producing Human Amniotic Epithelial Cells-only Membrane for Transplantation

“…For instance, hAECs are capable of differentiation into osteoblasts [4], insulin-producing 3D spheroids [5], granulosa cells [6], corneal epithelial cells [7], hepatic cells [8], progenitor of cortical neurons [9], and pancreatic lineage [10]. hAECs have a characteristic of immune privilege due to a low expression of surface marker major histocompatibility complex, class II, DR (HLA-DR) [11]. Many studies have showed that hAECs have therapeutic potential on multiple sclerosis, immunomodulation, inflammation suppression, angiogenesis promotion, oxidative stress inhibition, neurogenesis induction, matrix metalloproteinases regulation, and remyelination stimulation [12-14].…”