Rapid memory T-cell reconstitution recapitulating CD45RA-depleted haploidentical transplant graft content in patients with hematologic malignancies.

T-cell depletion of an HLA-haploidentical graft is often used to prevent GVHD, but the procedure may lead to increased graft failure, relapse and infections due to delayed immune recovery. We hypothesized that selective depletion of the CD45RA+ subset can effectively reduce GVHD through removal of naive T cells, while providing improved donor immune reconstitution through adoptive transfer of CD45RA- memory T cells. Herein, we present results from the first 17 patients with poor-prognosis hematologic malignancy, who received haploidentical donor transplantation with CD45RA-depleted progenitor cell grafts following a novel reduced intensity conditioning regimen without TBI or serotherapy.

Chimeric antigen receptor-redirected CD45RA-negative T cells have potent antileukemia and pathogen memory response without graft-versus-host activity.

Chimeric antigen receptor (CAR)-redirected cellular therapy is an attractive modality for cancer treatment. We hypothesized that allogeneic CAR-engineered CD45RA-negative T cells can control cancer and infection without the risk of graft-versus-host disease (GVHD). We used CD19(+) MLL-rearranged leukemia as prototype because it is an aggressive and generally drug-resistant malignancy.

1α,25-dihydroxyvitamin D3 in combination with transforming growth factor-β increases the frequency of Foxp3⁺ regulatory T cells through preferential expansion and usage of interleukin-2.

A high prevalence of vitamin D insufficiency and deficiency exists worldwide, which is associated with an increased incidence and severity of a range of immune-mediated diseases. This has resulted in considerable interest in the immunodulatory functions of vitamin D. The active form of vitamin D, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], has been shown to increase the frequency of Foxp3(+) CD4(+) T regulatory (Treg) cells when present at high concentrations or under strong T-cell stimulation in culture.