Why α-cell-rich areas of an islet have more leucocytes: In human islets, α-cells were reported to express more IL-1β, IL-6, and other non-classical MHC class 1 molecules than β-cells during T1D (Anquetil et al., 2017; Rajendran et al., 2020a; Benkahla et al., 2020; Rajendran et al., 2020b). This evidence concerns the gene IL1B and type 1 diabetes mellitus.