Figure 3. Affinity binding between human ghrelin and IgG assayed by SPR.

Representative SPR sensorgrams (a) of association and dissociation to ghrelin of IgG from obese (blue), controls (green) and AN patients (red) after single injection of 0.5 mg ml⁻¹ of IgG with low flow speed of 5 μl min⁻¹. Mean SPR response in RU between three study groups 5 min after association (b) and 5 min after dissociation (c) as indicated by arrows in (a). (b) ANOVA, P=0.002, Tukey’s **P<0.01, *P<0.05; (c) K–W test, P=0.009, Dunn’s **P<0.01, M-W test, ^#P<0.05. (Contr. n=14, AN n=12 and obese n=14, error bars, s.e.m.).