Autoimmune attack is complex thing, I'm currently working with bad case of diabetes 1 type, and it's hard to expect regeneration of beta-cells not having tamed this.
Not all forms of type 1 diabetes are autoimmune.
As far as the autoimmune forms of type 1 diabetes these are most often virally triggered. Autoimmunity also involves immune suppression through the adrenal glands. This is what leads to the over production of low affinity (nonspecific) antibodies.