Macrophage migration inhibitory factor in the human ovary: Presence in the follicular fluids and production by granulosa cells

Abstract

Cytokines play an important role in ovarian function. We unexpectedly found high expression of macrophage migration inhibitory factor (MIF) mRNA in human ovarian tissues. Hence, we examined the presence of MIF in the follicular fluid because the follicular microenvironment is important for oocyte fecundity. The follicular fluids were collected from ovaries of patients undergoing in vitro fertilization and embryo transfer. A higher amount of MIF was identified in the follicular fluid, 80.3 +/- 4.6 ng/ml (mean +/- SE), in which the concentration was significantly decreased as the size of the follicles increased. To detect MIF mRNA expression in the granulosa cells, reverse transcription-polymerase chain reaction was carried out and this showed an amplified transcript specific for MIF. Furthermore, the presence of MIF protein in the granulosa cells was confirmed by Western blot analysis. These results suggest the possibility that MIF mediates various immunological events in the process of oocyte development.