P-967: Human oocytes maturing in an inlammatory environment: Cytokines in follicular fluid and their correlation with in vitro fertilization (IVF) outcome measures

Abstract

Follicular fluid (FF) composition and the follicular somatic cells play an important role in the maturation of the developing oocyte within the human female ovary. Although the molecular composition of the FF is an indicator of the activities in the follicle, the FF composition has been poorly characterized and follicle-specific markers of ovarian function do not exist. Cytokines are produced by virtually all cells, have an array of functions, and have been implicated in the female reproductive tract in many areas including folliculogenesis, ovulation and repair, corpus luteum formation and pregnancy implantation. This study aims to delineate the presence of cytokines within human ovarian FF and correlate their concentration with in vitro fertilization (IVF) outcome measures. Large university basic science laboratory study. Patients undergoing oocyte retrieval were recruited and consented according to an approved protocol. FF was obtained after follicular measurement in 2 dimensions via transvaginal ultrasound (size > 14mm). Cellular components were removed with centrifugation and A/G chromatography. Sixteen FF samples were analyzed for 14 cytokines using microarray technology and repeated with two identical arrays. A second assay, multiplex sandwich enzyme linked immunosorbent assay (ELISA) with robotic array of 16 cytokines was preformed. Duplicate analyses were conducted on 20 FF samples from separate patients. Patient age, baseline follicle-stimulating hormone, body mass index, infertility diagnosis, gravity, parity, cycle protocol, number of oocytes retrieved, number of mature oocytes, fertilization rates, number of embryos transferred and cryopreserved, pregnancy rates and pregnancy outcome was collected. Data were analyzed using correlation coefficients, chi-square and students ttests where appropriate with a statistical significance set at p<0.05. Multiple cytokines were found in FF in high concentrations including Interleukins (IL) -1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-13, growth factors Vascular endothelial growth factor (VEGF) and Placental growth factor (PLGF), and Interferon-gamma (INF-g) and Tumor necrosis factor-alpha (TNF-a). Cytokines were highly correlated (p<0.001) with each other, especially ILs 4, 5, 6, 10, 12, 13, INF-g and TNF-a. VEGF and IL-8 were also highly correlated (p=0.028) with each other. IL-13 and VEGF were found to be significantly correlated with IVF outcome. As the IL-13 concentration increased the number of oocytes retrieved, the number of mature oocytes, and the pregnancy rate was found to decline (p<0.05). Increased VEGF content in the FF was correlated with a decreased number of oocytes retrieved and a decreased number of mature oocytes (p<0.05). Cytokines within human ovarian FF appear to play an important role in the follicular microenvironment and are present in some cases in surprisingly high concentrations. FF containing large amounts of inflammatory mediators supports the premise that follicular development is an inflammatory process. However, increased content of certain cytokines, such as IL-13 and VEGF, correlate with decreased IVF success and may therefore be detrimental to the follicular / oocyte environment. These factors could be used as potential markers for IVF outcome.