Second transplant with two unrelated cord blood units for early graft failure after haematopoietic stem cell transplantation

Alemtuzumab, Fludarabine, Low-Dose TBI, and Double Umbilical Cord Transplant for Primary Graft Failure in a Patient with Recurrent HLH

Graft failure occurs at relatively low frequency, but commonly in hemophagocytic lymphohistiocytosis (HLH), especially with umbilical cord blood transplant (UCBT). No standard approaches to management of graft failure exist. We present a challenging case of relapsed HLH following first UCBT with primary graft failure following second UCBT. We report a novel reduced intensity conditioning regimen of alemtuzumab, 4 Gy total body irradiation and fludarabine for salvage of primary graft failure followed by double UCBT. The reported patient successfully engrafted with 100% donor chimerism following salvage UCBT with no occurrence of acute or chronic graft-versus-host disease.

Second allogeneic hematopoietic cell transplantation for graft failure: poor outcomes for neutropenic graft failure

Graft failure (GF) after hematopoietic cell transplant (HCT) occurs in 5-30% of patients. GF can be accompanied by neutropenia (NGF) or can result with adequate neutrophils, but loss of donor chimerism (non-neutropenic graft failure, NNGF). In this report, we describe the outcomes of 95 patients treated with a second HCT for GF at the University of Minnesota; 62 with NGF and 33 with NNGF. The cumulative incidence of neutrophil recovery at 42 days after second HCT was 45% for NGF and 88% for NNGF. A second GF occurred in 34 NGF (55%) and in 9 NNGF (27%) patients. The incidence of Grade III-IV acute graft versus host disease (GVHD) was 8% (95% confidence interval (CI), 1-16%) and 12% (95% CI, 1-23%) for NGF and NNGF, respectively. From the 2nd HCT, 1-year overall survival (OS) was 44% (95% CI, 34-54%), [NNGF: 76% (95% CI, 57-87%) and NGF: 27% (95% CI, 17-39%)]. The most common cause of death after second HCT was infection (52%). In summary, the outcomes of second HCT after NGF and NNGF are different with much worse outcomes for NGF necessitating new approaches for this complication.

Successful early unmanipulated haploidentical transplantation with reduced-intensity conditioning for primary graft failure after cord blood transplantation in hematologic malignancy patients

Primary graft failure (pGF) is a frequent complication following cord blood transplantation (CBT). For those patients who will not experience autologous recovery, salvage transplantation should be performed as early as possible. However, standardized treatment protocols for pGF, such as the optimal stem cell source, preparative regimen and the ideal time for salvage transplantation, have yet to be determined. Therefore, we analyzed 17 hematologic malignancy patients who received unmanipulated haploidentical peripheral blood (PB) and BM transplantation with reduced-intensity conditioning (RIC) as a salvage therapy for pGF after CBT. The median interval between the two transplantations was 38 days. The RIC regimen for salvage transplantation consisted of fludarabine, antithymocyte globulin, CY and low-dose TBI. The neutrophil and plt engraftments were achieved in 14 (82.4%) and 13 (76.4%) patients, respectively. The cumulative incidences of grades II-IV and grades III-IV aGVHD were 35.3% and 17.6%, respectively. The cumulative incidence of chronic GVHD was 29.4%. After a median follow-up of 43 months, 10 of 17 patients remained alive in CR. The cumulative incidence of TRM at 180 days was 29.4%. The probability of 3-year OS and leukemia-free survival was 57.5%. Our results show that unmanipulated haploidentical PB and BM transplantation under a RIC regimen is an effective treatment for pGF after CBT.

Engraftment kinetics and graft failure after single umbilical cord blood transplantation using a myeloablative conditioning regimen

Umbilical cord blood transplant recipients are exposed to an increased risk of graft failure, a complication leading to a higher rate of transplant-related mortality. The decision and timing to offer a second transplant after graft failure is challenging. With the aim of addressing this issue, we analyzed engraftment kinetics and outcomes of 1268 patients (73% children) with acute leukemia (64% acute lymphoblastic leukemia, 36% acute myeloid leukemia) in remission who underwent single-unit umbilical cord blood transplantation after a myeloablative conditioning regimen. The median follow-up was 31 months. The overall survival rate at 3 years was 47%; the 100-day cumulative incidence of transplant-related mortality was 16%. Longer time to engraftment was associated with increased transplant-related mortality and shorter overall survival. The cumulative incidence of neutrophil engraftment at day 60 was 86%, while the median time to achieve engraftment was 24 days. Probability density analysis showed that the likelihood of engraftment after umbilical cord blood transplantation increased after day 10, peaked on day 21 and slowly decreased to 21% by day 31. Beyond day 31, the probability of engraftment dropped rapidly, and the residual probability of engrafting after day 42 was 5%. Graft failure was reported in 166 patients, and 66 of them received a second graft (allogeneic, n=45). Rescue actions, such as the search for another graft, should be considered starting after day 21. A diagnosis of graft failure can be established in patients who have not achieved neutrophil recovery by day 42. Moreover, subsequent transplants should not be postponed after day 42.

Cord blood full blood count parameters in Lagos, Nigeria

Introduction

Full blood count (FBC), one of the most frequently requested for laboratory investigations, is a simple, fast and cheap test and is a reliable indicator of health. Due to its usefulness in the assessment of health status of individuals, its parameters in cord blood, a major source of haemopoietic stem cell transplantation and an ideal source for laboratory investigations for newborns were determined to provide a useful guide to local neonatologists and stem cell transplant physicians.

Methods

Three millilitres of umbilical cord blood was collected from 130 normal birth weight newborns (69 males and 61 females) whose cord were clamped immediately after delivery, at a teaching hospital in Lagos, Nigeria and full blood count parameters were determined using Sysmex autoanalyzer, model KX-21N. Consented mothers of the newborns were selected based on, age between 18 and 45 years; uneventful pregnancy and delivery and haemoglobin (Hb) concentration ≥ 10 g/dL.

Results

There were no statistical gender differences in the mean values of Hb concentrations (M = 13.27 ±1.60 g/dL; F = 13.32±1.61g/dL; p = 0.93), total white cell count (M = 3.16±5.43 × 10⁹/L; F = 13.07±4.98 × 10⁹/L; p= 0.92), platelet count (M= 223.64± 64.21 × 10⁹/L; F = 226.69±80.83 × 10⁹/L; p = 0.81) and other parameters.

Conclusion

Mean values of full blood count parameters obtained in this study are comparable to reports from other studies in developing countries and could be a useful guide for neonatologists and stem cell transplant physicians in our geographical location.

In vitro evaluation of graft-versus-graft alloreactivity as a tool to identify the predominant cord blood unit before double cord blood transplantation

The transplantation of two cord blood (CB) units obtained from unrelated donors (double CBT) is an effective strategy for adult patients with hematologic malignancies. Sustained hematopoiesis after double CBT is usually derived from a single donor, and only a few transplantation recipients displaying a stable mixed donor-donor chimerism have been reported. We investigated the mechanisms underlying single-donor predominance in double CBT by studying in vitro the role of the graft-versus-graft cell-mediated immune effect in two-way mixed-lymphocyte culture, along with the contribution of differential hematopoietic progenitor (HP) potency in HP mixed cultures. Results for the two-way mixed-lymphocyte culture showed that despite the weak and variable alloantigen-specific cytotoxic potential displayed by CB mononuclear cells, an immune-mediated dominance for one of the two CB units was detected in the majority of experiments. Alloantigen-induced cytotoxic activity was directed toward both CB-HP and phytohemagglutinin (PHA)-activated T lymphoblastoid cells. The CB unit with the higher fold expansion of CD34(+) cells in single-expansion culture was prevalent in the HP mixed-expansion culture, as shown by DNA chimerism evaluation. Based on these data, we hypothesize that the dominant CB unit is able to develop prevalent cytotoxic activity toward activated lymphocytes of the other CB unit, thereby preventing them from exerting alloantigen-specific cytotoxic potential against both activated lymphocytes and HPs of the dominant unit. In accordance with this hypothesis, we propose the evaluation of alloantigen-induced cytotoxic activity generated in two-way mixed-lymphocyte culture and directed toward PHA-activated T lymphoblastoid cells as a tool to identify the potentially predominant CB unit before double CBT.

Haploidentical allogeneic haematopoietic stem cell transplantation as salvage therapy for engraftment failure after unrelated and autologous stem cell transplantation: a case report and review of the literature

Engraftment failure is a rare but life-threatening complication of haematopoietic stem cell transplantation (HSCT) and treatment of this condition is often challenging. This case report describes a patient with acute myeloid leukaemia and engraftment failure after unrelated donor allogeneic stem cell transplantation. Rescue treatment with granulocyte-colony stimulating factor and reinfusion of autologous 'back-up' stem cells failed, but transplantation of haploidentical donor stem cells following a fludarabine and antithymocyte globulin (ATG)-based conditioning regimen resulted in haematological reconstitution and long-term disease-free survival. The use of haploidentical donor stem cell transplantation as salvage therapy after engraftment failure in adult patients has not, to the authors' knowledge, been previously reported. Additionally, a review of the relevant literature is presented. This case report and literature review suggest that reinfusion of cryopreserved 'back-up' haematopoietic stem cells is a safe and effective salvage therapy for engraftment failure after allogeneic HSCT. Haploidentical donor stem cell transplantation after a fludarabine and ATG-based conditioning regimen could provide effective second-line therapy in adult patients.

Risk factors and options to improve engraftment in unrelated cord blood transplantation

Use of umbilical unrelated cord-blood (UCB) cells as an alternative source of hematopoietic cell transplantation has been widely used mainly for patients lacking an HLA-matched donor. UCB present many advantages over bone marrow or mobilized peripheral blood from volunteer donors, such as rapid availability, absence of risk for the donor, and decreased incidence of acute graft-versus-host disease. However, a significant clinical problem is delayed engraftment that is directly correlated with the number of hematopoietic stem cells in a cord-blood unit. The identification of prognostic factors associated with engraftment that can be easily modified (e.g., strategies for donor choice) and the development of new approaches including use of multiple donors, intrabone injection of UCB, ex vivo expansion, and cotransplantation with accessory cells are of crucial importance in order to circumvent the problem of delayed engraftment after UCB transplantation. Those approaches may increase the quality and availability of UCB for transplantation.

Graft failure in cord blood transplantation successfully treated with short-term reduced-intensity conditioning regimen and second allogeneic transplantation

Graft failure (GF) remains a major problem in cord blood transplantation (CBT). In 36 adult patients undergoing CBT at our hospital between July 2003 and December 2009, six patients developed GF (primary, n = 5; secondary, n = 1). All six patients underwent second stem cell transplantation (SCT). Three patients had acute myeloid leukemia, one had acute lymphoblastic leukemia, one had chronic myeloid leukemia, and one had aplastic anemia. Five patients were complicated with sepsis before the second SCT. The median elapsed time from first CBT to the diagnosis of primary GF was 27 days. Secondary GF was diagnosed on day 567. The median elapsed time from primary GF to second SCT was 9 days. In the patient with secondary GF, the elapsed time was 35 days. Cord blood grafts were used in 5 patients and a matched sibling donor in one patient. All 6 patients underwent second transplantation following a modified '1-day'-based preparative regimen consisting of fludarabine (30 mg/m(2), 1 day, n = 2; 2 days, n = 1; 3 days, n = 3), cyclophosphamide (2 g/m(2)), and total body irradiation (2 Gy). All patients achieved neutrophil engraftment, and the median elapsed time from second SCT to engraftment was 35 days. Four patients remain alive between 5 and 38 months after second SCT. '1-day'-based short-term conditioning may be a promising salvage regimen.

Successful second transplantation with non-myeloablative conditioning using haploidentical donors for young patients after graft failure following double umbilical cord cell transplantation

GF is a common and life-threatening complication of UCBT. Here, we report that successful second transplantation of five patients using G-CSF-mobilized maternal stem cells with non-myeloablative conditioning after GF following double UCBT. The median interval between the two transplants were 38 days. The first transplantation was administered after myeloablative conditioning for hematologic malignancies (n=3), and rabbit ATG in combination with cyclophosphamide for SAA (n=2). The second conditioning consisted of Flu and ATG-based non-myeloablative regimen. All five patients acquired quick and sustained engraftment after the second transplant. Treatment-related toxicity was minimal. Three patients developed acute GVHD (>grade II=1). Three patients developed chronic GVHD (limited=1, extensive=2). Severe infectious episodes were significant but manageable. With a median follow-up of 713 days (592-1127), all patients have currently had an event-free survival. These results indicate that a second transplant with non-myeloablative conditioning using mother as the donor for young patient after GF is feasible.

Overcoming the barriers to umbilical cord blood transplantation

Umbilical cord blood (UCB) transplantation (UCBT) has seen a marked increase in utilization in recent years, especially in the pediatric population; however, graft failure, delayed engraftment and profound delay in immune reconstitution leads to significant morbidity and mortality in adults. The lack of cells available for post-transplant therapies, such as donor lymphocyte infusions, has also been considered a disadvantage. To overcome the cell-dose barrier, the combination of two UCB units is becoming commonplace in adolescent and adult populations, and is currently being studied in pediatrics as well. In some studies, the use of two UCB units appears to have a positive impact on outcomes; however, engraftment is still suboptimal. A possible additional way to improve outcome and extend applicability of UCBT is via ex vivo expansion. Studies to develop optimal expansion conditions are still in the exploratory phase; however, recent studies suggest expanded UCB is safe and can improve outcomes. The ability to transplant across HLA disparities, rapid procurement time and decreased graft-versus-host disease (GvHD) seen with UCBT makes it a promising stem cell source and, while barriers exist, consistent progress is being made to overcome them.

Improving outcomes of cord blood transplantation: HLA matching, cell dose and other graft- and transplantation-related factors

The use of unrelated umbilical cord blood (UCB) as an alternative source of haematopoietic stem cells transplantation (HSCT) has been widely used for patients lacking a human leucocyte antigen (HLA) matched donor. One of the disadvantages of using UCB is the limited number of haematopoietic stem cells and, consequently, delayed engraftment and increased risk of early mortality. Many approaches have been investigated in the attempt to improve engraftment and survival. Among those, studies analysing prognostic factors related to patients, disease, donor and transplantation have been performed. Variable factors have been identified, such as factors related to donor choice (HLA, cell dose and others) and transplantation (conditioning and graft-versus-host disease prophylaxis regimens). This review will focus on the interactions between HLA, cell dose and other modifiable factors related to the UCB unit selection and transplantation that may improve outcomes after UCB transplantation.

Second unrelated donor hematopoietic cell transplantation for primary graft failure

Failure to engraft donor cells is a devastating complication after allogeneic hematopoietic cell transplantation (HCT). We describe the results of 122 patients reported to the National Marrow Donor Program between 1990 and 2005, who received a second unrelated donor HCT after failing to achieve an absolute neutrophil count of >or=500/microL without recurrent disease. Patients were transplanted for leukemia (n = 83), myelodysplastic disorders (n = 16), severe aplastic anemia (n = 20), and other diseases (n = 3). The median age was 29 years. Twenty-four patients received second grafts from a different unrelated donor. Among 98 patients who received a second graft from the same donor, 28 received products that were previously collected and cryopreserved for the first transplantation. One-year overall survival (OS) after second transplant was 11%, with 10 patients alive at last follow-up. We observed no differences between patients who received grafts from the same or different donors, or in those who received fresh or cryopreserved product. The outcomes after a second allogeneic HCT for primary graft failure are dismal. Identifying risk factors for primary graft failure can decrease the incidence of this complication. Further studies are needed to test whether early recognition and hastened procurement of alternative grafts can improve transplant outcomes for primary graft failure.

Umbilical cord transplantation: epilogue

The field of cord blood transplantation has come a long way since the first transplant more than 20 years ago. Advancements in the field will require continuing efforts to better understand hematopoietic stem and progenitor cell function and engraftment. Cautious optimism is inherent in the potential relevance and applicability of nonhematopoietic stem and progenitor cell types found in cord blood, and induced pluripotent stem cells generated from cord blood cells. Rigorous investigations and close interactions between scientific and clinical investigators are required to translate human in vitro and animal in vivo findings into clinical utility.

Second transplant with two unrelated cord blood units for early graft failure after cord blood transplantation for thalassemia

Early GF is a frequent complication following hematopoietic stem cell transplantation for patients with thalassemia. We report the outcome of double-unit CBT in three patients who developed early GF after CBT. The initial conditioning regimen consisted of i.v. Bu 14 mg/kg (day -9 to -6), i.v. Cy 200 mg/kg (day -5 to -2) and ATG at 120 mg/kg (day -4 to -1). They received GVHD prophylaxis with cyclosporine-A from day -3 and a short course of methylprednisolone (1 mg/kg i.v., every 12 h on days 5-19 with a taper, thereafter 25% decrease every other day). The interval between two transplants was seven and 10 months. The retransplant recipients were preconditioned with i.v. Bu 14 mg/kg (day -7 to -4), i.v. Cy 120 mg/kg (day -3 to -2) and ATG at 150 mg/kg (day -5 to -1 and +1 to +5). GVHD prophylaxis regimen was the same as the first transplant. Neutrophil engraftment were observed in all patients between day +15 and +26. All are alive, between nine and 11 months after retransplant. Our group reported successful utilization of double umblical cord blood grafts in thalassemia patients with early GF.

Second hematopoietic stem cell transplantation in myeloid malignancies

PURPOSE OF REVIEW

Hematopoietic stem cell and umbilical cord blood transplantation can be a life-saving procedure for many patients with myeloid malignancies. The posttransplant period, however, can be complicated by graft failure and disease relapse, prompting the need for further therapy. Herein, we review and examine the data of second allogeneic stem cell transplant after autologous, allogeneic and umbilical cord blood transplantation.

RECENT FINDINGS

Although large, prospective, multicenter trials are lacking, certain factors such as younger patient age, lower disease burden and a longer interval between first transplantation and relapse appear to portend a better prognosis for second transplant.

SUMMARY

Currently, only a selected group of patients without important comorbidities should be considered for second allogeneic transplantation. Strategies such as new immunosuppressive agents, antileukemia monoclonal antibodies, graft modification and use of molecularly targeted therapy are needed to decrease the morbidity and increase the efficacy of transplantation.

Successful salvage unrelated umbilical cord blood transplantation with two units after engraftment failure with single unit in severe aplastic anemia

Severe aplastic anemia (SAA) patients without an HLA-matched sibling donor need alternative treatment options. Umbilical cord blood transplantation (UCBT) has become an alternative means for treating various diseases, but it has not been proved to be a satisfactory method to treat SAA. Here, we report the case of a girl who underwent successful two-unit UCBT after engraftment failure with a single unit. Two-unit UCBT is proposed to have better engraftment potential and to offer a better chance of survival, according to some reports. Increased cell dose and graft-versus-graft reaction could contribute to these advantages. With this promising result, two-unit UCBT could be an alternative treatment option for patients with SAA without an HLA-matched donor.

Primary graft failure after umbilical cord blood transplant rescued by parental haplocompatible stem cell transplantation

AB Graft failure and aplasia are known complications of umbilical cord blood (UCB) hematopoietic stem cell transplantation (HSCT). In the absence of a second HSCT, graft failure is generally a fatal complication due to overwhelming infection. We describe 2 children with primary graft failure and life-threatening infections after UCB HSCT who were rescued by the use of related haplocompatible T-cell-depleted peripheral blood stem cell transplants. The rapid availability of haplocompatible donors and the brisk neutrophil recovery after haplocompatible peripheral blood stem cell transplant with high numbers of CD34+ cells make this an attractive rescue strategy for patients with graft failure after UCB HSCT.

Unrelated cord blood transplantation for severe congenital neutropenia: report of two cases with very different transplant courses

SCN is characterized by neutropenia, life-threatening infections, and progression to myelodysplastic syndrome/acute myelogenous leukemia. The only curative option is SCT, but few reports using UCB as a stem cell source exist. Here, we report two SCN patients transplanted with UCB. Patient 1 was transplanted at seven yr of age due to increasingly large injections of G-CSF (>100 microg/kg/day) and the risk of developing leukemia. He engrafted promptly and is clinically well and immune reconstituted >2 yr post-transplant. Patient 2 underwent UCB SCT at nine months of age for recurrent severe infections, despite high doses of G-CSF. He rejected his first graft, having 100% host cells on day +35, and immediately underwent a second UCB SCT. He engrafted but experienced late graft rejection six months after the second transplant. He received a third UCB SCT following a more immunosuppressive conditioning regimen. His course was complicated by HHV-6 viremia and gut GVHD, but he is now clinically well and has 99% donor engraftment >20 months post-transplant. We conclude that UCB is an acceptable stem cell source for SCN patients, but conditioning must be adequately immunosuppressive to ensure engraftment in patients without prior chemotherapy.

The harvest and use of autologous back-up grafts for graft failure or severe GVHD after allogeneic hematopoietic stem cell transplantation: a survey of the European Group for Blood and Marrow Transplantation

Autologous hematopoietic stem cells (HSCs) harvested as back-up prior to allogeneic hematopoietic SCT (HSCT) may potentially be useful in the treatment of graft failure or in cases with severe GVHD. Here, we studied the general policies and indications for autologous back-up harvest among the European Group for Blood and Marrow Transplantation centers in the year 2003. The outcome of patients receiving autologous back-up transfusion between 1998 and 2002 was evaluated retrospectively. The responses from 94 centers showed that 48 centers had a general policy with variable indications for autologous back-up harvest. Thirty-five patients with graft failure (25), GVHD (8) or relapse (2) retransplanted with autologous back-ups were reported. Autologous back-up transfusion was performed at a median of 35 days (patients with graft failure) or 90 days (patients with GVHD) after allogeneic HSCT. Within 100 days after autologous HSCT, 21 patients died from treatment-related complications (19) or relapse (2). Estimated overall survival at 1 year was 16% (95% CI 0-32%) for patients treated for graft failure and 13% (95% CI 0-37%) for GVHD patients. In conclusion, our data demonstrate that the indication for autologous back-up harvests is limited and that general storage and use cannot be recommended unless in selected prospective studies.

Double cord blood transplantation in patients with high risk bone marrow failure syndromes

Patients with bone marrow failure syndromes (BMFS) who reject a first allogeneic transplant or fail immunosuppressive therapy (IST) have an especially grim prognosis. We report 14 patients (eight adults, six children) transplanted with double cord blood transplantation (dUCBT) for BMFS. Neutrophil recovery was observed in eight patients, with full donor chimerism of one unit, and acute GVHD in 10. With a median follow-up of 23 months, the estimated 2 years overall survival was 80 +/- 17% and 33 +/- 16% for patients with acquired and inherited BMFS, respectively. Transplantation of two partially HLA-matched UCB thus enables salvage treatment of high-risk patients with BMFS.

Correction of chronic granulomatous disease after second unrelated-donor umbilical cord blood transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) is curative for chronic granulomatous disease (CGD), but many patients lack a suitably matched related donor. We report successful outcomes after mismatched, unrelated-donor umbilical cord blood transplantation (uUCBT) in two boys with X-linked CGD. Both patients experienced autologous recovery after first transplants, required second transplants to achieve durable donor engraftment, and are alive 27 and 15 months post-transplant. Both had invasive fungal disease and received granulocyte transfusions. In conclusion, uUCBT is effective in children with CGD, but immunosuppression in the conditioning regimen may need to be increased to decrease the risk of graft rejection.

Leukemia: cord blood for allogeneic stem cell transplantation

PURPOSE OF REVIEW

Cord blood is considered an acceptable alternative to hematopoietic stem cells. This review focuses on clinical results of cord blood transplantation including factors associated with transplantation outcomes for aiding graft selection. Immunological analysis of T cell recovery processes and approaches to cellular therapy using cord blood-derived immune cells are also discussed.

RECENT FINDINGS

To resolve problems with cord blood transplantation, including high toxicity especially in the early phase after transplant and delayed engraftment, a reduced intensity regimen and double cord blood units from different donors are applied. For adequate graft selection, cell dose and human leukocyte antigen compatibility are important to reduce transplant-related toxicity, although the importance of human leukocyte antigen compatibility seems to disappear in leukemia patients because of a possible graft-versus-leukemia effect in a human leukocyte antigen-mismatched setting. Immune reconstitution after cord blood transplantation is also important to reduce the risk of infectious complication. Recent technologies make it possible to generate antigen-specific T cells from naïve T cells from cord blood in vitro.

SUMMARY

Stem cell sources are now available for almost all leukemia patients. The efficacy of cord blood transplantation warrants further clarification by larger clinical experience and well designed studies. Efforts to reduce toxicity and improve engraftment are still in progress.