OBJECTIVE: To evaluate the stability over time of recently identified gonadotropin-releasing hormone receptor autoantibodies (GnRHR-AAbs) found in the serum of infertile patients with polycystic ovary syndrome (PCOS). Our assay may hold promise in future diagnostic testing for PCOS, however currently no data exists regarding antibody level stability.
DESIGN: Case series.
MATERIALS AND METHODS: Serum samples from a convenience sample of seven women with PCOS and infertility were assessed for GnRHR-AAbs levels over multiple time points (17 total) spanning, on average, a two year timeframe for all patients. All timepoints represent baseline AAb levels as the patients were not on hormonally modulating medications at the seleted times. The de-identified samples were screened by enzyme linked immunosorbent assay (ELISA) for GnRHR-AAbs using a synthetic 28-mer peptide (LifeTein, Somerset, NJ) from the second extracellular loop (ECL2) of human GnRHR as coating antigen and evaluated for optical density (OD) values. Statistical analyses were performed with paired t-tests using all sequential pairs of GnRHR values for evaluation of GnRHR AAb level total absolute change over time (TAC/T).
RESULTS: There was no significant difference between GnRHR AAb level values over time for each patient, p=0.39. Additionally, increased variation in AAb level over time (higher TAC/T) was not associated with higher GnRHR AAbs levels, p=0.23. Lastly, when evaluating the relationship of AAb level variation with other measures also averaged over time (estradiol level, age, body mass index (BMI), and antimullerian hormone level), only estradiol was found to have a significant association with higher estradiol levels and GnRHR AAb TAC/T, p=0.048.
CONCLUSIONS: Our initial investigations have shown that most patients in our study with PCOS have activating AAbs to GnRHR compared to ovulatory controls (1). In this case series we have demonstrated that GnRHR AAb levels are stable over time and AAb level consistency does not vary by baseline AAb level. Additionally, there may be an association between higher estradiol levels and GnRHR AAb level TAC/T.