Infusion of donor-derived CD8+ memory T cells for relapse following allogeneic hematopoietic cell transplantation

Abstract

Murine models showed that CD8+CD44hi memory T (TM) cells could eradicate malignant cells without inducing graft-versus-host disease (GVHD). We evaluated the feasibility and safety of infusing freshly isolated and purified donor-derived phenotypic CD8+ TM cells into adults with disease relapse after allogeneic hematopoietic cell transplantation (HCT). Phenotypic CD8 TM cells were isolated after unmobilized donor apheresis using a tandem immunomagnetic selection strategy of CD45RA depletion followed by CD8+ enrichment. Fifteen patients received CD8+ TM cells at escalating doses (1 × 106, 5 × 106, or 10 × 106 cells per kg). Thirteen received cytoreduction before CD8+ TM cell infusion, and 9 had active disease at the time of infusion. Mean yield and purity of the CD8+ TM infusion were 38.1% and 92.8%, respectively; >90% had CD8+ T effector memory phenotype, cytokine expression, and secretion profile. No adverse infusional events or dose-limiting toxicities occurred; GVHD developed in 1 patient (grade 2 liver). Ten patients (67%) maintained or achieved response (7 complete response, 1 partial response, 2 stable disease) for at least 3 months after infusion; 4 of the responders had active disease at the time of infusion. With a median follow-up from infusion of 328 days (range, 118-1328 days), median event-free survival and overall survival were 4.9 months (95% confidence interval [CI], 1-19.3 months) and 19.6 months (95% CI, 5.6 months to not reached), respectively. Collection and enrichment of phenotypic CD8+ TM cells is feasible, well tolerated, and associated with a low incidence of GVHD when administered as a manipulated infusion of donor lymphocytes in patients who have relapsed after HCT. This trial was registered at www.clinicaltrials.gov as #NCT01523223.

Conflict of interest statement

Conflict-of-interest disclosure: The authors declare no competing financial interests.

© 2018 by The American Society of Hematology.

Figures

Graphical abstract

Figure 1.

Representative flow analysis of peripheral blood apheresis collections from the preselection, post-CD45RA depletion, and CD8+enrichment steps. Cells were stained for expression of CD4, CD8, CD45RA, and CD45RO. Plots show CD45 gated events.

Figure 2.

Flow cytometric analysis, cytokine expression, mixed lymphocyte reaction, and cytokine secretion. (A) Representative flow analysis of 1 experiment repeated 5 times that shows cell composition and subsets from start to finish of preselection, post–CD45RA depletion, and post–CD8+ enrichment. Cells were stained for expression of CD45RA, CD45RO, and CD62L, and plots are shown for CD4+ and CD8+ gated cells at each step of the processing procedure. The surface phenotype of the CD45RA–CD8+-enriched cells is consistent with the phenotypic CD8+ TEM subset being predominantly CD45RA–CD45RO+CD62L–. The TEM cells ranged from 81.7% to 98.1% of the final cell composition. (B) Flow cytometric analysis of cytokine expression by enriched cell subsets. Cells were activated by ionomycin and phorbol myristate acetate, treated with monensin, and stained for expression of CD45, CD4, CD8, and CD45RA. Cells were fixed, permeabilized, and stained for INF-γ, and IL-2. Plots show comparison of IL-2 and IFN-γ expression in CD8+CD45RA–, CD8+CD45RA+, and CD4+CD45RA– cells as indicated. (C) Proliferation of CD8+CD45R– and CD4+ cells activated by co-culture with or without irradiated allogeneic stimulators and assessed by 3H-thymidine uptake during the last 24 hours of culture. Mean and standard deviations are shown (n = 4). (D) Cytokine secretion assessment in CD8+CD45RA– and CD4+ cells activated by co-culture with or without irradiated allogeneic stimulators. Supernatants from 7-day cultures were analyzed by flow cytometry using cytokine bead arrays for INF-γ, IL-2, and TNF-α (n = 4). Means with standard deviations are shown. Teff, T effector cells.

Figure 3.

Kaplan-Meier estimates of event-free survival (EFS) for the 15 patients receiving CD8+TMcell infusion.

Figure 4.

Kaplan-Meier estimates of overall survival (OS) for the 15 patients receiving CD8+TMcell infusion.