A coupling hypothesis for pancreatic-islet innervation in type 1 diabetes, and one falsifiable in-vitro test

Scope. This is a mechanism hypothesis and a proposal for one laboratory experiment. It is not medical advice, it describes no treatment or protocol, and it makes no claim that type 1 diabetes can be cured or reversed. Nothing in it should be acted on clinically. The hypothesis. That a component of type 1 diabetes pathogenesis is a failure of coupling between the autonomic nervous system and the pancreatic islet — specifically at the parasympathetic (vagal) innervation of the islet — with beta-cell loss a downstream consequence rather than the primary event. The motivation is existing experimental literature rather than any framework of the author's: reports that compromised pancreatic innervation precedes and contributes to islet autoimmunity; descriptions of autonomic and islet-innervation abnormalities in T1D; and the established vagal inflammatory reflex, in which cholinergic signalling through the alpha-7 nicotinic acetylcholine receptor suppresses TNF-alpha, IL-1beta and IL-6, a pathway with regulatory precedent for bioelectronic neuromodulation in another autoimmune disease. Those citations support the plausibility of the mechanism. They do not establish it, and they are not this note's result. What would distinguish it. If islet-innervation coupling sits upstream of beta-cell loss, then interventions acting only on the immune axis should preserve beta-cell function while administered and lose benefit on withdrawal, whereas an intervention that also restored autonomic coupling should be more durable. No efficacy claim is made; this is offered as a direction a properly designed study could probe. One cheap falsifiable test. A geometric model of the islet's resonance structure flags a specific low frequency near 33 Hz. The experiment is in vitro and inexpensive, and the null is what is pre-registered: in a matched beta-cell differentiation assay, a pulsed electromagnetic field at the flagged frequency does not outperform a control near 7 Hz. A clear and reproducible difference in favour of the flagged frequency would therefore be the finding, and its absence costs the hypothesis nothing it was not already willing to lose. The note also sets out the statistical design the test requires, in particular that wells are not independent units: replication is at the level of independent differentiations, analysed with a mixed model, and no power figure is claimed in advance of a pilot.