Unrelated umbilical cord blood transplantation and immune reconstitution

Abstract

This review highlights the unique features of immune reconstitution following unrelated cord blood transplantation (UCBT) that lead to heightened risk of infection-related mortality in the early post-UCBT period. There is no evidence that innate immunity is uniquely compromised after UCBT, but the development of antigen-specific cellular immunity is affected by numerical and qualitative deficits, primarily within the first 100 days. Nevertheless, beyond the first few months after UCBT there is no evidence for reduced graft-versus-leukemia (GVL) or anti-viral immunity compared to other hematopoietic cell therapy (HCT) modalities. Novel cellular therapies that are about to enter the clinical setting in the form of natural killer (NK) cell and T-cell therapies in the form of donor lymphocyte infusion (DLI) are also discussed.

Figure 1. Kaplan-Meier curve of survival (months) after UCBT in 330 consecutive patients

Death related to OI is the major cause of failure, most occurring by 6 months. Immune reconstitution after unrelated cord blood transplantation. Szabolcs P, Niedzwiecki D. Cytotherapy. 2007;9(2):111-122. Reprinted by permission of Taylor & Francis Group, http://www.informaworld.com.

Figure 2And 2B

(A) Time to death from all causes in the “Day 50” cohort by OI status. (B) Time to death from OI by presence or absence of severe GvHD. Immune reconstitution after unrelated cord blood transplantation. Szabolcs P, Niedzwiecki D. Cytotherapy. 2007;9(2):111-122. Reprinted by permission of Taylor & Francis Group, http://www.informaworld.com.

Figure 3

Cumulative incidence of leukemic relapse by positive (solid line) or negative (dotted line) proliferative response status. P=0.003, log-rank test for difference between curves. Reprinted from Biol Blood Marrow Transplant, Vol 12, Parkman R, Cohen G, Carter SL, et al., Successful immune reconstitution decreases leukemic relapse and improves survival in recipients of unrelated cord blood transplantation, 919-927, ©2006, with permission from Elsevier.

Figure 4A and 4B. Cumulative incidence of relapse

(A) Overall cumulative incidence and 1-KM probability of relapse. (B) Cumulative incidence and 1-KM probability f relapse by stage of disease (first and second CR vs. other). This research was originally published in Blood. Kurtzberg J, Prasad VK, Carter SL, et al. Results of the Cord Blood Transplantation Study (COBLT): clinical outcomes of unrelated donor umbilical cord blood transplantation in pediatric patients with hematologic malignancies. Blood. 2008;112:4318-4327. © the American Society of Hematology.

Figure 5A and 5B

(A) Cumulative incidence of relapse after nonmyeloablative umbilical cord blood transplantation for patients with follicular lymphoma/chronic lymphocytic leukemia (—), large-cell /mantle-cell lymphoma (---), and HL (- - -). Reprinted from Biol Blood Marrow Transplant, Vol 15, Brunstein CG, Cantero S, Cao Q, et al., Promising progression-free survival for patients low and intermediate grade lymphoid malignancies after nonmyeloablative umbilical cord blood transplantation, 214-222, ©2009, with permission from Elsevier. (B) Estimated progression-free survival (PFS) according to histologic subtype. Patients with indolent non-Hodgkin’s lymphoma (NHL); yellow line), mantle-cell lymphoma (blue line), aggressive NHL (grey line) and Hodgkin’s lymphoma (red line). Reprinted with permission. © 2008 American Society of Clinical Oncology. All rights reserved. Rodrigues, CA et al: J Clin Oncol 27(2), 2009:256-263.

Figure 6. Th1/Tc1 cytokine secretion profile and Granzyme A expression in the expanded T cell progeny

4-color FACS dotplot profile of viable T lymphocytes contrasting the starting day 0 and post-expansion day 14 progeny. Surface detection of indicated antibodies is presented except for IFNγ, IL-2, TNFα and Granzyme B which were detected following permeabilization and intracellular staining. The relative size of the indicated T cell subsets in a quadrant is expressed as the percentage of total viable T cells. Representative experiment, n=10. Reprinted from Biol Blood Marrow Transplant, Vol 14, Mazur MA, Davis CC, Szabolcs P, Ex Vivo Expansion and Th1/Tc1 Maturation of Umbilical Cord Blood T Cells by CD3/CD28 Costimulation, 1190-1196, ©2008, with permission from Elsevier.

Figure 7A and 7B

(A) CD3⁻/CD16⁺/CD56^+dim/bright subset expansion as determined by flow cytometry. The CD3⁻ lymphocyte population was gated and used as a reference to determine the percentages of CD3⁻/CD16⁺/CD56^+dim and CD3⁻/CD16⁺/CD56^+bright expressions of non-adherent UCB MNCs from CTE versus CTCTE versus CTECT after 48 hours in culture with AB/CY versus SF medium alone. Results represent mean ± SEM (n=3); CD56^+dim: P <.05, CTE, CTECT, CTCTE AB/CY versus medium alone; CD56^+bright: P <.01, CTE, CTECT, CTCTE AB/CY versus medium alone. (B) NK Cytotoxicity in NOD/SCID Mouse Xenografted with K562 cells. Effect of UCB ex vivo expanded in medium alone versus AB/CY on survival of NOD/SCID mice that received a xenograft of K562 cells. NOD/SCID mice were injected with 10 × 10⁶ human K562 cells 3 days after tumor cell injection; groups of mice (n=10) received intraperitoneal injections of CTECT UCB cells (1 × 10⁷ cells/animal) stimulated with medium alone or CTECT UCB cells (1 × 10⁷ cells/animal) stimulated with AB/CY. Parallel sham injections of sterile PBS served as a control group. Injections of ex vivo expanded UCB cells or PBS continued every 7 days for 14 days. Tumor survival was monitored daily and animals were killed when they become moribund with disseminated tumor burden. Reprinted from Biol Blood Marrow Transplant, Vol 12, Ayello J, van de Ven C, Fortino W, et al., Characterization of cord blood natural killer and lymphokine activated killer lymphocytes following ex vivo cellular engineering, 608-622, ©2006, with permission from Elsevier.

Figure 8A and 8B

(A) Expression of activating c-lectin receptor CD94/NKG2D after ex-vivo expansion of cryopreserved/thawed/re-cryopreserved/re-thawed (CTCT) cord blood (CB) cells cultured for 2 to 7 days in AB/CY as determined by flow cytometry. CD94/NKG2D expression was significantly increased after incubation at 7 days versus 2 days (p <0.001). Results represent mean ± SEM (n=6). Representative dot plot of CD94/NKG2D expression of CB mononuclear cells (MNCs) after 2-7 days in culture. The lymphocyte population was gated and used as a reference to determine the specific subsets. (B) Expression of NK degranulation marker LAMP-1 (CD107a) of cryopreserved/thawed/re-cryopreserved/re-thawed/ex-vivo expanded (CTCTE) cord blood (CB) cells cultured for 2 to 7 days in AB/CY as determined by flow cytometry. Expression of CD107a in CB CTCTE cells was significantly increased (p <0.001) when comparing day 7 to day 2. Results represent mean ±SEM (n=6). Representative dot plot of CD107a expression of CTCTE CB mononuclear cells (MNCs) after 2-7 days in culture. The lymphocyte population was gated and used as a reference to determine the specific subsets. Reprinted from Exp Hematol, Ayello J, van de Ven C, Cairo E, et al., Characterization of natural killer (NK) and natural killer-like T (NKT) cells derived from ex-vivo expanded and activated cord blood mononuclear cells: Implications for adoptive cellular immunotherapy (ACI), ©2009, with permission from Elsevier.