Characteristics and Dynamics of TCR Repertoire in Patients With Hematological Malignancies After Allo-HSCT

Graft-versus-Host Disease (GVHD) and relapse, which is mainly due to lack of Graft-versus-Leukemia (GVL), are the most frequent and severe complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). T cells expanded from mature T cells in the graft play a dominant role in development of GVHD and GVL early after allo-HSCT. Recent applications of high-throughput sequencing (HTS) to the T cells repertoire open a new avenue for us to look deeply into how these T cells dynamically adjust in the context of the recipient's environment. The main goal of this research study is to set up a mathematical model based on T cell receptor (TCR) sequencing to enable prediction for the key immunologic outcomes early post-transplantation. This study will deepen the understanding of the molecular mechanisms driving the most deadly post-transplantation complications, and serve as convincing evidence upon which to choose a better donor and a more proper transplantation approach. This observational trial will perform HTS for TCR β-chain complementarity determining region 3 (CDR3) repertoires of grafts and peripheral blood samples from recipients post-transplantation and analyze the relationship between dynamics of TCR CDR3 repertoires and clinical outcomes early post-transplantation, especially including GVHD and relapse. The investigators want to know how the antigen environment in recipients drives dynamics of mature T cells from grafts in order to use the new discovered rules to better predict and treat the disease process.