Different co-culture systems have the same impact on bovine embryo transcriptome

Area of Science:

• * Reproductive Biology
• * Embryology
• * Cell Biology

Background:

• * Co-culture systems with feeder cells (BOEC or VERO) are explored to enhance bovine embryo development.
• * Supplementing SOF medium with feeder cells at 20% oxygen is a recent trend, but its benefits are unclear.
• * Standard SOF medium at 5% oxygen is established for mimicking oviduct fluid.

Purpose of the Study:

• * To investigate the impact of co-culture systems (BOEC or VERO) with SOF medium on bovine early embryo development and transcriptomes.
• * To compare the effects of different oxygen concentrations (5% vs. 20%) and feeder cell types on embryo development.

Main Methods:

• * Transcriptome analysis of bovine embryos cultured in four conditions: SOF with BOEC at 20% O2, SOF with VERO at 20% O2, SOF at 5% O2, and SOF at 20% O2.
• * Embryos were analyzed at the 16-cell and blastocyst stages.
• * Developmental rates and gene expression patterns were compared across conditions.

Main Results:

• * Co-culture systems did not enhance developmental rates compared to SOF medium at 5% oxygen.
• * No significant differences in embryo transcriptome were observed between BOEC and VERO co-culture systems.
• * In blastocysts, co-culture with BOEC or VERO appeared to negatively regulate STAT3 and STAT5 pathways, potentially reducing cell survival and differentiation compared to SOF at 5% oxygen.

Conclusions:

• * The origin of feeder cells (BOEC or VERO) does not influence bovine early development in SOF medium.
• * Co-culture systems do not provide a beneficial impact on bovine early development when used with SOF medium.
• * Culture at 5% oxygen in SOF medium remains an effective approach for bovine embryo development.