Overexpression of HLA class I molecules on T cells among type 1 diabetes Brazilian patients

To evaluate the membrane expression of histocompatibility (HLA) class I (A–C) molecules on lymphomononuclear cells involved in the pathogenesis of type 1 diabetes, we studied 20 newly diagnosed Brazilian patients and 20 matched controls. The coexpression of HLA and cluster of differentiation (CD) molecules was evaluated by flow cytometry. Compared to controls, patients presented increased fluorescence intensity of HLA class I molecules on CD3 +, CD4 + and CD8 + cells. Patients exhibiting the HLA-DQB1 ∗0201 and/or DQB1 ∗0302 alleles presented increased expression of class I molecules in relation to HLA-matched healthy controls. The increased HLA class I expression in subsets of T cells may be due to the proinflammatory profile of the disease as well as to the presence of diabetes susceptibility alleles.