Using this analysis method to test a larger sample population, we found that unactivated monocytes from T1D patients had significantly higher activated STAT5 without ex vivo activation than monocytes from healthy, non-autoimmune controls, as detected in small volume (<100 μl) whole peripheral blood samples stored up to 24 hr at 4°C (control mean 8.460%±7.833SD, T1D 30.97%±18.00, p<0.0001, pair-wise Mann Whitney U test, Figure 3a). Here, STAT5B is linked to type 1 diabetes mellitus.