Interestingly, this study also showed orally administered butyrate in preclinical T1DM models to suppress this ‘bystander’ potentiation of CD8+ T cell autoreactive effector functions [44], highlighting how the pre-existing state of the gut microbiome may be a relevant factor in ‘autoimmunity’ and symptom severity. This evidence concerns the gene CD8A and type 1 diabetes mellitus.