The revolving door of ‘residual beta cell function’: cause or effect in medical reports?

Excerpt

To the Editor: In a recent research letter in Diabetologia, Richardson et al [1] reported the persistence of antibodies against at least one of the following islet autoantigens in 57% of a cohort of patients from the ‘Golden Years’ study [2] with long-standing type 1 diabetes: GAD, insulinoma-associated protein 2 (IA2), zinc transporter 8 (ZnT8). The patients had a mean disease duration of 55 years (range 51–75 years), and the frequency of antibodies against GAD was higher than the frequency against IA2 or ZnT8. The authors argue that the detection of serum autoantibodies in long-standing disease may be indicative of an immune response sustained by the continuous presentation of islet antigens. This hypothesis would support the persistence of islet regeneration in type 1 diabetic patients after several years of disease. It would imply that autoantibodies could be an indirect marker of islet regeneration and, more specifically, of residual beta cell activity [1]. …