Related Experiment Video
Updated: Oct 17, 2026

Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization
Published on: October 24, 2025
Periovulatory human oocytes, cumulus cells, and ovarian leukocytes express type 1 but not type 2
M P Smith1, R S Mathur, S D Keay
1University of Bristol and St. Michaels Hospital, Bristol, United Kingdom.
Objective:
To further elucidate cortisol metabolism in the follicular microenvironment at the time of oocyte retrieval, the presence of 11beta-hydroxysteroid dehydrogenase (HSD) messenger (m)RNA transcripts in oocytes; cumulus cells; granulosa cells; and CD45(+), CD15(+) leukocytes was assessed semiquantitatively.
Design:
Controlled study using semiquantitative assessment of 11beta-HSD mRNA.
Setting:
University IVF center.
Patient(S):
Twenty-six patients undergoing controlled ovarian hyperstimulation for assisted conception.
Intervention(S):
Metaphase II oocytes; cumulus cells; granulosa cells, and CD45(+), CD15(+) leukocytes from individual follicular fluid aspirates.
Main Outcome Measures:
Semiquantitative analysis of PCR products after total RNA extraction and complementary DNA synthesis.
Result(S):
Periovulatory human oocytes; cumulus cells; CD45(+), CD15(+) leukocytes; and granulosa cells consistently express type 1 but not type 2 11beta-HSD mRNA. Expression of mRNA is greatest in cumulus cells. Type 1 11beta-HSD mRNA expression varies considerably in all cell types and among individual follicles and patients.
Conclusion(S):
These studies of mRNA expression suggest that the enzymes present both in and around the periovulatory oocyte will favor a high-cortisol environment.
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