Analysis of protein expression (secretome) by human and mouse preimplantation embryos.
OBJECTIVE
To analyze the protein production into the surrounding medium (secretome) of both human and mouse embryos and correlate these findings with ongoing blastocyst development. Along with improvements in culture systems, there is renewed focus on the development of noninvasive viability assays in human IVF. Because the majority of biologic functions are carried out by proteins, it is important to study the dynamics of the proteome during embryonic development and its response to both internal and external stimuli.


METHODS
Experimental study.


METHODS
Research laboratory.


METHODS
Couples undergoing infertility treatment donated with consent spent culture media for research.


METHODS
Analysis by time-of-flight mass spectrometry.


METHODS
Protein profiles of spent culture media.


RESULTS
Distinctive and significantly different secretome profiles were observed at each embryonic developmental stage (P<0.05). Correlation of day 5 secretome data with ongoing blastocyst development revealed an 8.5-kDa protein biomarker that was significantly up-regulated (P<0.05). The best candidate for this protein biomarker was ubiquitin, which has been implicated in the implantation process of mammalian species.


CONCLUSIONS
This approach to analyze the secretome should not only further our understanding of embryo physiology but provide the basis for the development of noninvasive assays of embryo viability in human IVF.
Katz-Jaffe
Mandy G
MG
Colorado Center for Reproductive Medicine, Englewood, USA. mkatz-jaffe@colocrm.com
Schoolcraft
William B
WB
Gardner
David K
DK
D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism*; D001757:Blastomeres / Q000378:metabolism*; D002478:Cells, Cultured; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D020543:Proteome / Q000378:metabolism*; D013045:Species Specificity
D020543:Proteome