Morphological study of fully and partially isolated early human follicles

Objective: To compare the development of fully and partially isolated human follicles by using various culture systems. Design: Human ovarian material was incubated with collagenase and deoxyribo nuclease. Fully and partially isolated follicles (30-50 mum) were dissected and studied under light and electron microscopy. The follicles were then c ultured on and within various matrices. Fully isolated follicles were also cocultured with stromal cells. Setting: Rabin Medical Center, a major care and referral center. Patient(s): Women undergoing laparoscopy. Intervention(s): None. Main Outcome Measure(s): Microscopy studies, follicular measurements. Result(s): Electron microscopy studies revealed an excess of lipid droplets in the granulosa cells of freshly isolated follicles. An increase in folli cular size and granulosa cell number was observed only in the fully isolate d follicles cultured within collagen gels for 24 hours. Most of the partial ly isolated follicles detached from the collagen gels. When cultured on col lagen, extracellular matrix, and poly-L-lysine, both the fully and the part ially isolated follicles deteriorated within the first 24 hours; coculture with stromal cells had no beneficial effect. Conclusion(s): The excess in lipid droplets in granulosa cells of isolated follicles might suggest that the isolation process does not yield completel y healthy follicles. However, despite this finding, our studies show that f ully isolated follicles, but not partially isolated follicles, can grow wit hin, but not on, a culture matrix. (C) 2001 by American Society for Reprodu ctive Medicine.