GAD2 and type 1 diabetes mellitus: In this manuscript we provide evidence, by means of an extended analysis of T1D patients and healthy controls, that multimer technology can offer the additional advantage of identifying peculiar antigen-reactive subpopulations, preliminary characterized, such as the CD3-CD8dullCD56+ GAD65 AA 114–122 pentamer reactive ‘memory-like’ NK cells after a short GAD65 AA 114–122 peptide antigenic expansion.