Metalloproteinase activity has a role in equine chorionic girdle cell invasion.

This research studies the role of a certain kind of enzyme, metalloproteinase, in enabling a type of cell found in horse embryos, the chorionic girdle cell, to invade the uterine wall, a key process in pregnancy. An in-vitro system was used and it was found that the metalloproteinase was indeed instrumental in cell invasion.

Objective and Methodology

• The research aims to study the invasion mechanism of equine chorionic girdle cells into the extracellular matrix – with a focus on the proteinase activity. This is a critical mechanism in equine pregnancy. Proteinases are enzymes capable of degrading proteins, which plays a crucial role in the cells’ mobility and invasive capacity.
• The researchers established an in vitro system using Day 34 chorionic girdle cell preparations cultured on Matrigel Invasion Chambers. This allowed them to study the cell invasion process in a controlled laboratory environment.
• Some cell preparations were cultured in the presence of proteinase inhibitors (aprotinin, bestatin, and 1,10-phenanthroline) to identify the proteinase activity associated with girdle cell invasion.

Findings

• The invasive cells cultured in the Matrigel Invasion Chambers showed physical characteristics consistent with in vivo cup cell morphology – they were binucleate with noticeable nucleoli and often highly vacuolated.
• Furthermore, these cells produced equine Chorionic Gonadotropin (eCG), highlighting their functionality under laboratory conditions.
• Of the various proteinase inhibitors used, only 1,10-phenanthroline – a metalloproteinase inhibitor – was found to inhibit chorionic girdle cell invasion through Matrigel.
• Zymography, a method to detect enzyme activity, characterized the chorionic girdle cell supernatants and confirmed that the proteinases produced by these cells were indeed metalloproteinases. The molecular masses of these enzymes were approximately 72 and 95 kDa.

Conclusion

• The results attained from this research indicate that equine chorionic girdle cells have the ability to degrade matrix through metalloproteinase activity in their invasion process during pregnancy.
• This metalloproteinase activity has been found to be necessary for trophoblast invasion in mice and humans, suggesting a universal mechanism of implantation across these species.