The human ovarian follicular fluid level of interleukin-8 is associated with follicular size and patient age.

OBJECTIVE

To investigate the relationship between interleukin-8 (IL-8) in the human ovarian follicle and follicular size, patient age, and fertility factors in IVF cycles.

DESIGN

Prospective study.

SETTING

University hospital research laboratory and infertility clinic.

PATIENT(S): Women undergoing IVF with oocyte retrieval.

INTERVENTION(S): Follicular fluid (FF) aspiration, oocyte isolation, FF storage, and experimental studies.

MAIN OUTCOME MEASURE(S): Quantization of IL-8 by ELISAs and protein microarray; high-performance liquid chromatography (HPLC) followed by ELISA and Western blotting to evaluate alpha(2)-macroglobulin (alpha(2)M) bound IL-8; association of IL -8 to follicular size, patient age, and IVF outcomes.

RESULT(S): Samples of FF from 63 patients contained an average of 629.59 pg/mL of IL-8 with 50%-70% bound to alpha(2)M. Large follicles contained higher levels of IL-8 than small follicles (937.34 vs. 86.97 pg/mL). The IL-8 concentration in the large follicles of women of young age was higher than that of older reproductive age women (1,373.61 vs. 673.29 pg/mL). There were no statistically significant associations found between IL-8 concentration and other IVF cycle factors or pregnancy outcome.

CONCLUSION(S): Our findings indicate that IL-8 is present in FF, both in its free and alpha(2)M-bound state, and its concentration is correlated with follicular size and patient age.