Deep sequencing and flow cytometric characterization of expanded effector memory CD8+CD57+ T cells frequently reveals T-cell receptor V β oligoclonality and CDR3 homology in acquired aplastic anemia.

Deep sequencing and flow cytometric characterization of expanded effector memory CD8+CD57+ T cells frequently reveals T-cell receptor Vβ oligoclonality and CDR3 homology in acquired aplastic anemia. Haematologica. 2018 Feb 01;: Authors: Giudice V, Feng X, Lin Z, Hu W, Zhang F, Qiao W, Fernandez Ibanez MDP, Rios O, Young NS Abstract Oligoclonal expansion of CD8+CD28- lymphocytes has been considered indirect evidence for a pathogenic immune response in acquired aplastic anemia. A subset of CD8+CD28- cells with CD57 expression termed effector memory cells is expanded in several immune mediated diseases and may have a role in immune surveillance. We hypothesized that effector memory CD8+CD28-CD57+ cells may drive aberrant oligoclonal expansion in aplastic anemia. We found CD8+CD57+ cells frequently expanded in the blood of aplastic anemia patients, with oligoclonal characteristics by flow cytometric Vβ usage analysis: skewing in 1 to 5 Vβ families and frequencies of immunodominant clones ranging from 1.98% to 66.5%. Oligoclonal characteristics were also observed in total CD8+ cells from aplastic anemia patients with CD8+CD57+ cell expansion by T-cell receptor deep sequencing, as the presence of 1 to 3 immunodominant clones. Oligoclonality was confirmed by T-cell receptor repertoire deep sequencing of enriched CD8+CD57+ cells, which showed also decreased diversity compared to total CD4+ and CD8+ cell pools. From analysis of complementa...
Source: Haematologica - Category: Hematology Authors: Tags: Haematologica Source Type: research