Developmentally-regulated IL6-type cytokines signal to germ cells in the human fetal ovary. Eddie SL et al. Fetal ovarian development and primordial follicle formation are imperative for adult fertility in the female. Data suggest the interleukin (IL)6-type cytokines, leukemia inhibitory factor (LIF), IL6, oncostatin M (OSM) and cilary neurotrophic factor (CNTF), are able to regulate the survival, proliferation and differentiation of fetal murine germ cells (GC) in vivo and in vitro. We postulated that these factors may play a similar role during early human GC development and primordial follicle formation. To test this hypothesis, we have investigated the expression and regulation of IL6-type cytokines, using qRT-PCR and immunohistochemistry. Expression of transcripts encoding OSM increased significantly across the gestational range examined (8-20 weeks), whilst expression of IL6 increased specifically between the first (8-11 weeks) early second (12-16 weeks) trimesters, co-incident with the initiation of meiosis. LIF and CNTF expression remained unchanged. Expression of the genes encoding the LIF and IL6 receptors, and their common signalling subunit gp130, were also found to be developmentally-regulated, with expression increasing significantly with increasing gestation. LIFR and gp130 proteins localised exclusively to GCs, including oocytes in primordial follicles, indicating this cell type to be the sole target of IL6-type cytokine signalling in the human fetal ovary. These data establish that IL6-type cytokines and their receptors are expressed in the human fetal ovary, and may directly influence germ cell development at multiple stages of maturation.
Expression regulated by
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Ovarian localization
Oocyte, Granulosa
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Immunocytochemical detection and reverse transcription polymerase chain reaction expression of oncostatin M (OSM) and its receptor (OSM-Rbeta) in human fetal and adult ovaries Abir R, et al .
OBJECTIVE: To investigate the immunocytochemical expression and presence of mRNA transcripts of oncostatin M (OSM) and its exclusive receptor (OSM-Rbeta) in ovaries from human adults and fetuses. DESIGN: Immunocytochemical and reverse transcription polymerase chain reaction (RT-PCR) study. SETTING: Major tertiary care and referral academic centers. PATIENT(S): Ten women and girls undergoing laparoscopic ovarian biopsy and 30 women undergoing second-trimester and third-trimester pregnancy terminations. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Microscopic morphometric analysis, immunocytochemistry for OSM and OSM-Rbeta, and RT-PCR analyses. RESULT(S): There was strong to moderate immunocytochemical staining for OSM in both oocytes and granulosa cells of follicles from primordial stages onwards in ovaries from both fetuses and adults/adolescents. OSM-Rbeta was detected mainly in the oocytes. Transcripts of OSM and OSM-Rbeta RNA were detected by RT-PCR analyses. CONCLUSION(S): The expression of OSM and its receptor in ovarian tissue from fetuses and women suggests a possible role of OSM in growth initiation of human primordial follicles.