PTPRN and diabetes mellitus: To standardize the definition of LADA, the Immunology of Diabetes Society proposed the following criteria: patients should be at least 30 years of age, positive for at least one of the four antibodies commonly found in type 1 diabetic patients (anti-ICAs, anti-GAD65, anti-IA2, and anti-insulin), and should not have been treated with insulin within the first 6 months of diagnosis.