CD8A and type 1 diabetes mellitus: This would indicate that alterations in the gut microbiome are relevant to different aspects of T1DM pathoetiology and pathophysiology, namely changes in intercellular interactions of cells in pancreatic islets as well as in the maintenance of memory CD8+ T cells arising from CD8+ T cells initially activated due to the intercellular interactions driving changes in the mitochondrial melatonergic pathway of pancreatic β-cells.