Abstract
Purpose :
Corneal stroma-derived mesenchymal stem cells (CS-MSC) have not yet been directly compared on a genetic level with bone marrow MSC (BM-MSC), with or without the inclusion of xenofree conditions. This results in inconclusiveness with regards to the MSC-like properties of corneal stromal cells. The potential of corneal-derived MSCs in tissue engineering applications for Ophthalmology is yet to be explored. We hypothesize that CS-MSC show comparable expression of key MSC genes to BM-MSC, in accordance to findings on a phenotypical and functional level, and that xenofree culture does not alter genetic expression patterns in CS-MSC.
Methods :
Human CS-MSC were obtained from six donors and expanded in both standard conditions (basal medium with the addition of 10% Fetal Bovine Serum – FBS) and xenofree conditions using 10% Human Platelet Lysate (HPL) as a replacement for FBS. At passage 4, the cells were harvested and RNA isolation was followed by cDNA extraction and qPCR for 85 key genes for human MSC. Human BM-MSCs at passage 6 (provided by Veneto Eye Bank) were used as control. Phenotypic characterization using flow cytometry and trilineage differentiation was performed to confirm the MSC-like properties of corneal stroma-derived cells as required by the International Society for Cellular Therapy (ISCT).
Results :
Out of 85 genes tested, 71 showed no differential expression between bone marrow-derived and corneal stroma-derived MSCs in normal or xenofree conditions. Of the 14 genes where expression differed between BM- and CS-MSCs, 12 were not expressed in BM. Genes with variable expression include: ABCB1, IL10, PROM1, CSF3, IL1B, TNF, KDR, SOX2, BMP7, HNF1A, FGF10 and WNT3A. Flow cytometry showed that corneal stroma-derived MSCs, like BM-SCs, met the ISCT criteria and were positive for CD73, CD90, CD105, CD13, CD29, CD44, CD166 and negative for CD11b, CD 14, CD19, CD34, CD45, CD79a, HLA-DR and were able to differentiate into osteocytes, chondrocytes and adipocytes regardless of the cultures being xenofree or not.
Conclusions :
Despite portraying an identical phenotype as described by the ISCT criteria, MSCs derived from the corneal stroma show a different genetic profile to those that are derived from bone marrow. Further research is warranted in order to determine if CS-MSCs would be superior to BM-MSCs for corneal stromal tissue engineering.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.