VPS18 and type 1 diabetes mellitus: After 4 days of stimulation, no significant difference was observed upon Pep3 administration on the percentages of CD8+ Treg PD1+ cells (Fig 5a), CD8+ Treg PD1low cells (Fig 5b) and CD8+ Treg PD1high cells (Fig 5c) in either HD or type 1 diabetes PBMC.