The Functional Capacities of Peripheral Blood Regulatory T Cells after an Allogeneic Stem Cell Transplant Correlate with the Risk of Graft-Versus-Host Disease

This is the authors' abstract. We don't add key points for this paper.

The immunologic reconstitution is ultimately responsible of the clinical outcome of patients who have undergone an allogeneic stem cell transplantation (SCT). The occurrence of graft-versus-host disease (GVHD), which represents the major cause of morbidity and mortality after the transplant correlates with the concentration in the peripheral blood (PB) of regulatory T cells (Tregs). In this study we aim at demonstrating that not only the concentration but also the functional capacities and the degree of activity of Tregs act as an important regulator of alloreactivity and may help to predict the risk of acute and chronic GVHD in the post-transplant period. Sixteen patients who underwent an allogeneic SCT were evaluated at 1 year from transplant. Tregs were expanded from the PB of these patients and from 8 normal donors; their expansion capacity, phenotype, suppressor activity and IL-10 production were measured. Tregs expanded from patients without GVHD exerted a higher suppressive function on the proliferative reaction of T cells and showed a higher IL-10 production capacity compared to patients with acute or chronic GVHD. These results document that the functional activity and the suppressor capacity of Tregs after an allogeneic SCT may protect from GVHD, and support the design of clinical protocols based on the infusion of expanded and activated Tregs.