Evaluation of immunoglobulins subclasses and free-light chains in non-obese patients with polycystic ovary syndrome and correlations with hormonal and metabolic parameters: preliminary data

OBJECTIVE: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism and hyperinsulinemia that contribute to create a state of chronic low-grade inflammation. We performed an observational case-control study to investigate inflammatory and immunological parameters, such as IgG subclasses and free light chains (FLCs) and hemolytic complement activity (CH50) in non-obese PCOS, evaluating their relations with metabolic and hormonal parameters. PATIENTS AND METHODS: 36 subjects were studied: 16 PCOS patients (mean +/- SEM 27.13 +/- 1.82 age; BMI 24.1 +/- 0.9 kg/m(2)); 20 controls (aged 26.05 +/- 0.73; BMI 20.8 +/- 0.4 kg/m(2)). The blood sample was collected for metabolic and hormonal parameters, IgG subclasses, k and lambda FLCs, CH50. Hormones were measured by immunochemiluminometric assays; metabolic parameters by enzymatic assays; subclasses of IgG, FLCs, and CH50 were evaluated by the turbidimetric method. RESULTS: PCOS patients showed vs. controls lower IgG1, IgG2, IgG3 (mean +/- SEM 3.76 +/- 0.29 g/l, 2.63 +/- 0.20, 0.62 +/- 0.06, 0.34 +/- 0.08 vs. 6.49 +/- 0.35, 4.28 +/- 0.25. 0.84 +/- 0.07, 0.33 +/- 0.04. respectively) and higher levels of FLCs (k 12.22 +/- 0.71 vs. 6.03 +/- 0.30, A 10.10 +/- 0.79 vs. 8.04 +/- 0.48 g/l) and CH50 (48.64 +/- 2.65 vs. 36.51 +/- 1.38 U/ml); we found correlation between IgG2 and free-testosterone (r=0.72. p=0.005) and CH50 and vitamin D (r=0.54, p=0.04): an inverse correlation was found between IgG1 and. respectively. ACTH (r=-0.57, p=0.02) and cortisol (r=0.78. p=0.001) in PCOS. CONCLUSIONS: In the complex scenario of low-grade inflammation in non-obese PCOS, we showed lower levels of main subclasses of IgG and higher CH50 levels, suggesting the involvement of other mechanisms other than the classical pathway of complement activation; FLCs could be attractive to monitor inflammation degree, disease activity and influence on hormonal status.

Automated summary

In this study, lower levels of main subclasses of IgG and higher CH50 levels were found in non-obese PCOS patients compared to controls. FLCs could be a potential indicator for monitoring inflammation degree, disease activity, and impact on hormonal status in PCOS.