PTPRC and type 1 diabetes mellitus: The profile for increased NOD islet–associated PNAs correlated with a 58- to 140-fold increase in insulitis CD45+ leukocytes from 10–12 weeks to T1D onset versus background levels in control islets (Figure 1H) and, like blood PNA levels (Figure 1D), with histological evidence for increased islet inflammation/destructive insulitis in the pancreas of separate groups of age-matched NOD mice (Figure 1E).