RESUMO
Background: Xeno-free generation of human embryonic stem cells (hESCs) is important to prevent potential animal contaminations in culture for advanced cell-based therapeutic applications. Xeno-free production of hESCs is the first step for manufacturing clinical-grade hESC lines. Objective: To produce new hESC lines in xeno-free condition. Materials and Methods: This lab resources report was conducted at Stem Cell Biology Research Center, Yazd, Iran from 2019-2022. 4 new hESC lines from 11 (10 fresh and 1 frozen) donated surplus discarded human embryos were established. In this study, we report the xeno-free derivation of new Yazd hESC lines (Yazd4-7), without using immunosurgery, by culturing intact zona-free blastocysts obtained from discarded embryos onto the YhFF#8 cells as a feeder layer in a microdrop culture system. The pluripotency gene expression profile of the cell lines was assessed by reverse transcription polymerase chain reaction and the expression of specific surface markers was detected using immunofluorescent staining. In vitro differentiation was induced using embryoid body formation and gene expression profile of 3 germ layers and germ cells. Reverse transcriptase polymerase chain reaction was investigated to prove their pluripotent capacity. Results: In sum, we have been able to generate 4 new hESC lines (Yazd4-7) from 11 discarded embryos in xeno-free culture conditions using a micro drop culture system and YhFF#8 as a human source feeder layer. Conclusion: The outcome of this work can be the foundation for the future allogeneic cell-based therapeutic application using clinical grade good manufacturing practice-derived hESC derivatives.
RESUMO
Background: Fibroblasts from different parts of the human body have been used in cell biology, drug discovery and cell therapy studies. One of the most available sources of human fibroblasts is neonatal foreskin. Not only do these cells have wound-healing applications, but they are also the most popular source for pluripotent stem cell biotechnology. Moreover, several studies have indicated that different sources of fibroblasts display similar features to mesenchymal stem cells. Objective: Generation and establishment of new human foreskin fibroblast cell lines called Yazd human foreskin fibroblasts (YhFFs). Materials and Methods: In this lab resources study, the production of 3 YhFF cell lines (YhFF#8, YhFF#17, and YhFF#18) is reported. Their biological features were characterized using immunofluorescence, polymerase chain reaction, and flow-cytometry for mesenchymal markers such as fibronectin, vimentin, CD44, CD73, CD90, CD105, and hematopoietic markers CD34 and CD45. Results: The YhFF cell lines were passaged more than 40 times and their normal karyotype was checked using G-binding. Similarly to previous reports, the flow cytometry analysis revealed that the YhFF cell lines displayed mesenchymal stromal cell characteristics. Conclusion: This study will contribute to the development of clinical-grade cell-based products such as micro-vesicles and exosomes for future therapeutic applications in regenerative medicine.
RESUMO
BACKGROUND: Cell banking of initial outgrowths from newly derived human embryonic stem cells (hESCs) requires an efficient freezing method. Vitrification is used for the preservation of gametes and early embryos in assisted reproduction techniques (ART). Moreover, vitrification was applied for cryopreservation of hESCs using open pulled straws. OBJECTIVE: To derive and characterize new hESC lines and then use Cryotech and Cryowin tools for their vitrification. MATERIALS AND METHODS: Human ESC lines were generated in a microdrop culture system using mouse embryonic fibroblasts (MEFs) as the feeder layer; this was later scaled up using both MEFs and Yazd human foreskin fibroblasts batch 8 (YhFF#8). To bank the cell lines, master cell banks of 100 Cryotech and Cryowin tools were produced for each individual cell line using the vitrification method; flasks of hESC lines were also cryopreserved using a conventional slow-freezing method. RESULTS: The pluripotency of cell lines was assessed by their expression of pluripotency-associated genes (OCT4/POU5F1, NANOG, and SOX2) and markers such as SSEA4, TRA-1-60, and TRA-2-49. Their in vitro capacity to differentiate into germ layers and germ cells using embryoid body (EB) formation and monolayer culture was assessed by screening the expression of differentiation-associated genes. The chromosomal constitution of each hESC line was assessed by G-banding karyotyping. CONCLUSION: Cryotech and Cryowin tools used to vitrify new hESCs at an early stage of derivation is an efficient method of preserving hESCs.
