A five-day course of 50 μg of anti-TCR β mAb reversed >80% of new-onset T1D in NOD mice, and close to 60% reversal was seen in anti-TCRβ mAb resistant overtly diabetic NOD mice after treating them with a combination of anti-TCRβ mAb and Ngn3-Btc gene transfer. The gene discussed is NEUROG3; the disease is type 1 diabetes mellitus.