Pancreatic lymph nodes (PLN) are the central location for the autoimmune response that leads to type 1 diabetes (T1D), yet no histological studies of this crucial step in pathogenesis of human diabetes exist. In this study, we request sections from T1D and matched control PLN to allow us to follow up our preliminary observations showing that replicating germinal centers are diminished in recent onset T1D. In particular, we will focus characterizing the structure and cellular content of PLN in T1D and will test the hypothesis that lack of germinal center replication reflects attempted regulation of the immune response.