Cumulus Cells
Specialized granulosa cells surrounding the oocyte that provide metabolic support and are removed during ICSI preparation.
Full Definition
Cumulus cells are a subset of granulosa cells that form a dense layer around the mature oocyte within the cumulus-oocyte complex. These cells play crucial roles in oocyte maturation, providing nutrients and signaling molecules. During oocyte retrieval, cumulus cells accompany the oocyte and their presence and appearance can indicate oocyte maturity and quality. For ICSI procedures, cumulus cells must be removed through enzymatic treatment and mechanical stripping to visualize the oocyte for injection. The cumulus expansion pattern serves as one indicator of oocyte developmental competence.
Usage
Usage note: Distinguish from corona radiata, which refers specifically to the innermost layer of cumulus cells.
In Context
- "Cumulus cells were enzymatically removed to assess oocyte maturity before ICSI procedures." — Laboratory protocol
- "The oocyte exhibited good cumulus cell expansion indicating appropriate maturation." — Embryology report