surface plasmon resonance reveals a different pattern of proinsulin autoantibodies concentration and affinity in diabetic patients表面等离子体共振揭示了一个不同的模式在糖尿病患者胰岛素原的自体抗体浓度和亲和力.pdf

Surface Plasmon Resonance Reveals a Different Pattern of Proinsulin Autoantibodies Concentration and Affinity in Diabetic Patients ´ Aldana Trabucchi, Luciano L. Guerra, Natalia I. Faccinetti, Ruben F. Iacono, Edgardo Poskus, Silvina N. Valdez* School of Pharmacy and Biochemistry, University of Buenos Aires (UBA), and Humoral Immunity Institute Prof. Ricardo A. Margni (IDEHU), National Research Council (CONICET)-UBA, Buenos Aires, Argentina Abstract Type 1 diabetes mellitus (DM) is characterized by autoimmune aggression against pancreatic beta cells resulting in absolute deficiency of insulin secretion. The first detectable sign of emerging autoimmunity during the preclinical asymptomatic period is the appearance of diabetes-related autoantibodies. In children at risk for type 1 DM, high-affinity Insulin autoantibodies reactive to proinsulin, are associated with diabetes risk. Autoantibodies are usually measured by radioligand binding assay (RBA) that provides quasi-quantitative values reflecting potency (product between concentration and affinity) of specific autoantibodies. Aiming to improve the characterization of the specific humoral immune response, we selected surface plasmon resonance (SPR) as an alternative method to measure proinsulin autoantibodies (PAA). This novel technology has allowed real time detection of antibodies interaction and kinetic analysis. Herein, we have employed SPR to characterize the PAA present in sera from 28 childhood-onset (mean age 8.31 64.20) and 23 adult-onset diabetic patients ($65 years old, BMI,30) in terms of concentration and affinity. When evaluating comparatively samples from both groups, childhood-onset diabetic patients presented lowe