Culture and vitrification of human preembryos
Despite improvements in stimulation protocols, culture media formulations and laboratory protocols, the success rates in human IVF remain disappointingly low. The ability to successfully cryopreserve supernumerary embryos in a given IVF cycle without losing significant embryo viability is essential to maximize the cumulative benefit of a given treatment cycle. Therefore, studies on culture, cryopreservation and gene expression of human embryos fertilized in vitro were performed.
In these studies the impact of culture media on fertilization of human oocytes in vitro was investigated. Furthermore, the impact of growth factor supplementation to in vitro culture media and embryo survival and cryodamage after vitrification were studied. Using in situ hybridization and immunohistochemistry methods, the expression of genes in the human Fallopian tube, endometrium, and pre-implantation embryos and in human embryonic stem cells (hES) cells was studied.
The findings can be summarized as follows: in vitro culture media has impact on normal fertilization. Supplementation of growth factors to in vitro culture media implicates a physiological role in regulating pre-implantation development. Vitrification of embryos is an effective way of cryopreservation. In situ hybridization, immunohistochemical and matrix assisted laser desorption/ionization time of flight mass spectrometry methods are versatile tools in reproductive medicine research.
These findings will help to identify markers for embryo development and characterisation of hESC. Furthermore, knowledge obtained will give us tools to improve formulations of culture and cryopreservation media, which in turn might increase the overall results in IVF treatment and maximise the usage of hESC.
List of scientific papers
I. Hambiliki F, Sandell P, Yaldir F, Stavreus-Evers A. A prospective randomized sibling-oocyte study of two media systems for culturing cleavage-stage embryos-impact on fertilization rate. J Assist Reprod Genet. 2011, 28(4), 335-41.
https://doi.org/10.1007/s10815-010-9518-0.
II. Hambiliki F, Hanrieder J, Bergquist J, Hreinsson J, Stavreus-Evers, Wånggren K. Glycoprotein 130 promotes human blastocyst development in vitro. Fertil Steril. 2013 May; 99(6):1592-9.
https://doi.org/10.1016/j.fertnstert.2012.12.041.
III. Kartberg AJ, Hambiliki F, Arvidsson T, Stavreus-Evers A, Svalander P. Vitrification with DMSO protects embryo membrane integrity better than solutions without DMSO. Reprod Biomed Online. 2008, 17(3), 378-84.
https://pubmed.ncbi.nlm.nih.gov/18765008
IV. Hambiliki F, Ström S, Zhang P, Stavreus-Evers A. Co-localization of NANOG and OCT4 in human pre-implantation embryos and in human embryonic stem cells. J Assist Reprod Genet. 2012 Jun 29.
https://doi.org/10.1007/s10815-012-9824-9.
V. Wånggren K, Lalitkumar PG, Hambiliki F, Ståbi B, Gemzell-Danielsson K, Stavreus-Evers A. Leukaemia inhibitory factor receptor and gp130 in the human Fallopian tube and endometrium before and after mifepristone treatment and in the human preimplantation embryo. Mol Hum Reprod. 2007, 13 (6) 391-7.
https://doi.org/10.1093/molehr/gam013
History
Defence date
2014-06-04Department
- Department of Clinical Science, Intervention and Technology
Publisher/Institution
Karolinska InstitutetMain supervisor
Stavréus-Evers, AnneliPublication year
2014Thesis type
- Doctoral thesis
ISBN
978-91-7549-577-4Number of supporting papers
5Language
- eng