Comparison between cytokine concentration in follicular fluid of poor and high responder patients and their influence of ICSI-outcome

Abstract

Objective: The aim of this study was to compare the cytokine concentration in follicular fluid (FF) of low and high responder intracytoplasmic sperm injection (ICSI) patients and to find out the impact of these cytokines in FF on ICSI outcome.

Design: The levels of insulin-like growth factor (IGF)-I, IL-6, IL-8, epidermal growth factor (EGF), platelet-derived growth factor (PDGF), granulocyte-macrophage-colony stimulating factor (GM-CSF) were measured from low and high responder ICSI patients, the results were compared between the two groups and their influence on ICSI outcome was analysed.

Material and methods: A total of 49 low (G.I) and 34 high (G.II) responder patients were enrolled in this study. FF was collected at the time of oocyte retrieval and measured either by enzyme-linked immunosorbent assay (IL-6, IL8, EGF, PDGF, GM-CSF) or radio immuno assay (IGF-I).

Results: The concentration of IL-6 (pg/mL), IL-8 (pg/mL), IGF-I (ng/mL), PDGF (pg/mL), EGF (pg/mL), GM-CSF (pg/mL) in G.I was 6.0 +/- 4.3, 288.1 +/- 139.2, 0.416 +/- 0.089, 249.8 +/- 150.1, 9.12 +/- 5.5 and 1.45 +/- 2.10 and the corresponding value in G.II was 7.4 +/- 4.8, 208.6 +/- 64.0, 0.431 +/- 0.094, 387.6 +/- 36.0, 8.9 +/- 5.4 and 1.8 +/- 3.3, respectively. Only the PDGF concentration showed a significant (P = 0.007) difference between the two groups. Besides, negative correlations were found between PDGF and fertilization rate (r = -0.287; P = 0.046) of G.I. The mean number of retrieved (6.4 +/- 2.3 versus. 15.7 +/- 5.4) and fertilized (3.6 +/- 1.6 versus 7.0 +/- 4.5) oocytes differ significantly (P = 0.001) between the two groups. The fertilization rate was significantly higher in G.I than in G.II (60.9 +/- 25.1 versus 43.4 +/- 20.7%).

Conclusion: There was no significant difference between IGF-I, IL-6, IL-8, EGF and GM-CSF concentrations of low and high responder patients. Besides, PDGF was significantly (P = 0.007) higher in high responder compared with low responder patients. Moreover, in poor responder patients, a negative correlation was found between PDGF and fertilization rate. However, the cytokine levels in FF of the patients undergoing controlled ovarian hyperstimulation for ICSI could not be used as a marker of oocyte fertilization and implantation potential.