Affinity kinetics of leptin-reactive immunoglobulins are associated with plasma leptin and markers of obesity and diabetes

Plasma levels of leptin-reactive IgG (a). Representative examples of curve fits for the affinity kinetic analysis of a control subject (b), obese (c), obese T2D (d) and lean T2D (e) patients. Affinity kinetics between human leptin and IgG showing: dissociation equilibrium constants (KD, f), association rates (small Ka, g) and dissociation rates (small Kd, h). The data shown are median？±？interquartile range values. f K–W test, p？=？0.084; M–W test, ？p？<？0.05 obese vs. controls. h K–W test, p？=？0.026; Dunn’s *p？<？0.05 obese vs. controls; M–W test, ？p？<？0.05 obese vs. lean T2D, ？？p？<？0.01 obese vs.ObT2D. Filled circles indicate values statistically identified as outliers. (Controls, n？=？30; Obese, n？=？20; ObT2D, n？=？28 and lean T2D, n？=？30, error bars: interquartile range).ObT2D, Obese T2D; T2D, type 2 diabete