Samenvatting
Human leukocyte antigen G (HLA-G) is a tolerogenic molecule that acts on cells of both innate and adaptive immunity. This molecule has been associated with tumor progression, transplantation, placentation as well as the protection of the allogeneic fetus from the maternal immune system.
We investigated HLA-G mRNA and protein expression in undifferentiated human embryonic stem cells (hESC) derived from the inner cell mass (ICM) of blastocysts. HESC self-renew indefinitely in culture while maintaining the potential to differentiate into all cell types of the body, providing an unlimited source of cells for therapy.
HLA-G mRNA was found in three early and late passage hESC, as assessed by real time RT-PCR. Qualitative RT-PCR showed a different isoform expression pattern, although HLA-G1 mRNA was found in all three lines. Protein expression was demonstrated by immunocytochemistry and confirmed by flow cytometry and ELISA on a hESC extract. Binding of HLA-G with its ILT2 receptor demonstrated the functional active status.
In order to verify this finding in a physiologically relevant setting, HLA-G protein expression was investigated during preimplantation development. We demonstrated HLA-G protein expression in blastocysts were we find it in trophectoderm (TE) but also in ICM cells. Co-expression of HLA-G and NANOG, which is known to be expressed in some nuclei of blastocyst ICM cells, confirmed these cells to be ICM cells. During blastocyst development, a down-regulation of HLA-G in the ICM cells was present.
This data might be important for cell therapy and transplantation since undifferentiated hESC can contaminate the transplant of differentiated stem cells and develop into malignant cancer cells.
We investigated HLA-G mRNA and protein expression in undifferentiated human embryonic stem cells (hESC) derived from the inner cell mass (ICM) of blastocysts. HESC self-renew indefinitely in culture while maintaining the potential to differentiate into all cell types of the body, providing an unlimited source of cells for therapy.
HLA-G mRNA was found in three early and late passage hESC, as assessed by real time RT-PCR. Qualitative RT-PCR showed a different isoform expression pattern, although HLA-G1 mRNA was found in all three lines. Protein expression was demonstrated by immunocytochemistry and confirmed by flow cytometry and ELISA on a hESC extract. Binding of HLA-G with its ILT2 receptor demonstrated the functional active status.
In order to verify this finding in a physiologically relevant setting, HLA-G protein expression was investigated during preimplantation development. We demonstrated HLA-G protein expression in blastocysts were we find it in trophectoderm (TE) but also in ICM cells. Co-expression of HLA-G and NANOG, which is known to be expressed in some nuclei of blastocyst ICM cells, confirmed these cells to be ICM cells. During blastocyst development, a down-regulation of HLA-G in the ICM cells was present.
This data might be important for cell therapy and transplantation since undifferentiated hESC can contaminate the transplant of differentiated stem cells and develop into malignant cancer cells.
| Originele taal-2 | English |
|---|---|
| Tijdschrift | 6th International Meeting Stem Cell Network North Rhine Westphalia |
| Status | Published - 2011 |