Evans syndrome (ES) is a rare disorder characterized by combined autoimmune thrombocytopenia and autoimmune hemolytic anemia. Several studies have documented a number of B cell defects, whereas only limited information is currently available about the T cell subset.A wide panel of immunological analyses aiming specifically at a quantitative and qualitative evaluation of the T cell compartment was performed in an unusual case of ES. The peripheral distribution of the T cell subsets, the diversity of the T cell receptor (TCR) repertoires, the cytokine profile and the T cell apoptosis have been longitudinally evaluated.On first investigation, flow-cytometric immunophenotyping showed a remarkable alteration of T cell homeostasis with deeply reduced CD4+ naive T cells and recent thymic emigrants. This was seen in association with increased levels of T cell activation and apoptosis. Consistently with these data the cytokine profile was characterized by high interferon-gamma and low interleukin-2 levels. Staining for CD4 and CD25 molecules showed decreased percentages of circulating regulatory T cells according to the autoimmune nature of ES. Finally, restricted TCR repertoires were demonstrated by a skewed TCR beta chain variable (TCRBV) gene usage as well as oligoclonal third complementarity-determining region (CDR3) profiles. A deterioration of the above-mentioned parameters and a worsening of the clinical condition were observed during the follow-up requiring more intensive treatments.The demonstration of multiple T cell defects, in addition to providing pathogenetic information, is likely to alter both acute treatment and outcome of ES.

作者：Antonello, Giovannetti；Marina, Pierdominici；Antonella, Esposito；Maria, Cagliuso；Giuseppina, Stifano；Anna Maria, Giammarioli；Angela, Maselli；Walter, Malorni；Felice, Salsano；Fernando, Aiuti

来源：International archives of allergy and immunology 2008 年 145卷 3期