The consensus on indications, conditioning regimen, and donor selection of allogeneic hematopoietic cell transplantation for hematological diseases in China-recommendations from the Chinese Society of Hematology

[Impact of poor graft function on cytomegalovirus pneumonia in patients who have undergone haploidentical stem cell transplantation]

Objective: To retrospectively analyze the impact of primary PGF on CMV pneumonia in patients who have undergone haplo-HSCT. Methods: The clinical data of 122 patients who underwent haplo-HSCT at the Peking University Institute of Hematology from 2011-2012 were retrospectively reviewed. The incidence rate of CMV pneumonia between PGF and good graft function (GGF) was compared, and the factors were analyzed. In addition, outcomes in PGF patients with CMV pneumonia have been described. Results: Total 122 patients were retrospectively reviewed, and of these, 26 (21.3% ) had PGF, while 96 (78.7% ) had GGF. In addition, 15 patients had CMV pneumonia, and the median time to the development of CMV pneumonia was 103 (31-262) days; the 1-year cumulative incidence of CMV pneumonia was 12.3% (95% CI 6.2% -18.4% ) . In patients with primary PGF and GGF after Haplo-HSCT, the incidence of CMV pneumonia was 30.8% (8/26) and 7.3% (7/96) , respectively (P=0.002) . Moreover, 24 patients had CMV viremia (92.3% ) , while of the 96 GGF patients, 79 (82.3% ) had CMV viremia (P=0.212) . In multivariate analysis, the results showed that primary PGF had a significant influence on CMV pneumonia (P=0.005) . Compared with those without CMV pneumonia, patients with CMV pneumonia had poorer overall survival 37.3% (95% CI 11.2% -63.4% ) vs. 78.9% (95% CI 72.0% -87.6% ) (χ(2)=16.361, P<0.001) . The 1-year overall survival (OS) was 25.0% (95% CI 0% -55.0% ) and 50.0% (95% CI 26.9% -73.1% ) (χ(2)=4.656, P=0.031) in PGF patients with (8/26) and without (18/26) CMV pneumonia. Conclusion: The incidence of cytomegalovirus pneumonia in patients with primary poor graft function increases and the survival rate decreases.

Antithymocyte Globulin for Matched Sibling Donor Transplantation in Patients With Hematologic Malignancies: A Multicenter, Open-Label, Randomized Controlled Study

PURPOSE

The role of antithymocyte globulin (ATG) in preventing acute graft-versus-host disease (aGVHD) after HLA-matched sibling donor transplantation (MSDT) is still controversial.

PATIENTS AND METHODS

We performed a prospective, multicenter, open-label, randomized controlled trial (RCT) across 23 transplantation centers in China. Patients ages 40-60 years with standard-risk hematologic malignancies with an HLA-matched sibling donor were randomly assigned to an ATG group (4.5 mg/kg thymoglobulin plus cyclosporine [CsA], methotrexate [MTX], and mycophenolate mofetil [MMF]) and a control group (CsA, MTX, and MMF). The primary end point of this study was grade 2-4 aGVHD on day 100.

RESULTS

From November 2013 to April 2018, 263 patients were enrolled. The cumulative incidence rate of grade 2-4 aGVHD was significantly reduced in the ATG group (13.7%; 95% CI, 13.5% to 13.9%) compared with the control group (27.0%; 95% CI, 26.7% to 27.3%; P = .007). The ATG group had significantly lower incidences of 2-year overall chronic GVHD (27.9% [95% CI, 27.6% to 28.2%] v 52.5% [95% CI, 52.1% to 52.9%]; P < .001) and 2-year extensive chronic GVHD (8.5% [95% CI, 8.4% to 8.6%] v 23.2% [95% CI, 22.9% to 23.5%]; P = .029) than the control group. There were no differences between the ATG and control groups with regard to cytomegalovirus reactivation, Epstein-Barr virus reactivation, 3-year nonrelapse mortality (NRM), 3-year cumulative incidence of relapse (CIR), 3-year overall survival, or 3-year leukemia-free survival. Three-year GVHD relapse-free survival was significantly improved in the ATG group (38.7%; 95% CI, 29.9% to 47.5%) compared with the control group (24.5%; 95% CI, 16.9% to 32.1%; P = .003).

CONCLUSION

Our study is the first prospective RCT in our knowledge to demonstrate that ATG can effectively decrease the incidence of aGVHD after MSDT in the CsA era without affecting the CIR or NRM.

Impact of antithymocyte globulin on outcomes of allogeneic hematopoietic cell transplantation with TBI

The impact of the use of antithymocyte globulin (ATG) following a total body irradiation (TBI)-based myeloablative conditioning regimen has been poorly explored. We retrospectively analyzed 724 patients who underwent a first allogeneic hematopoietic cell transplantation (allo-HCT) following a TBI-based conditioning regimen for acute myeloid leukemia (AML) and compared the outcomes of 251 (35%) patients who received ATG (ATG group) with 473 (65%) patients who did not (non-ATG group). Median follow-up of surviving patients was 59 months (interquartile range, 28-83). The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) for non-ATG and ATG groups in the first 100 days was 33% vs 24%, respectively (P = .0098). The 2-year cumulative incidence of chronic graft-versus-host disease (cGVHD) was reduced significantly in the ATG group in comparison with the non-ATG group (46% vs 34%, P = .003). Using multivariate analysis, in vivo T-cell depletion (ATG group) was independently associated with a decreased incidence of grade II-IV aGVHD (hazard ratio [HR], 0.28; P < .001), grade III-IV aGVHD (HR, 0.21; P < .001), cGVHD (HR, 0.63; P = .02), and nonrelapse mortality (NRM) (HR, 0.54; P = .02). Relapse risk, overall survival, and leukemia-free survival were similar between the 2 groups. Our results suggest that the addition of ATG to TBI-based myeloablative conditioning for allo-HCT in AML patients results in a significant reduction in aGVHD and cGVHD, translating into a significant reduction in NRM without increasing the relapse rate.

Monocyte subsets in bone marrow grafts may contribute to a low incidence of acute graft-vs-host disease for young donors

Young donors are associated with a lower cumulative incidence of acute graft‐vs‐host disease (aGVHD) after allogenic haematopoietic stem cell transplantation (allo‐HSCT) than old donors. Although grafts are harvested from healthy donors, it is unclear whether donor age is associated with aGVHD occurrence owing to its effect on cell compositions in grafts. Moreover, the differences in monocyte subsets in grafts between young and old donors and the association between monocyte subsets in bone marrow (BM) grafts and aGVHD remain to be elucidated. In the current study, non‐classical monocytes and the CD4⁺/CD8⁺ T cell ratio were remarkably decreased in BM grafts in donors <30 years old. Multivariate analysis further revealed that the level of non‐classical monocytes in BM grafts (≥0.31 × 10⁶/kg) was an independent risk factor for the occurrence of II‐IV aGVHD. In summary, our data indicate that non‐classical monocytes in BM grafts may help identify patients at high risk for aGVHD after allo‐HSCT. Although further validation is required, our results suggest that the low level of non‐classical monocytes and a low ratio of CD4⁺/CD8⁺ T cell in BM grafts may be correlated with the lower incidence of aGVHD in young donors.

Comparison of efficacy and health-related quality of life of first-line haploidentical hematopoietic stem cell transplantation with unrelated cord blood infusion and first-line immunosuppressive therapy for acquired severe aplastic anemia

We retrospectively compared the efficacy and health-related quality of life (HRQoL) of (1) first-line haploidentical hematopoietic stem cell transplantation (haplo-HSCT, n = 146) combined with unrelated cord blood (UCB) infusion and (2) first-line immunosuppressive therapy (IST, n = 219) in acquired severe aplastic anemia (SAA) patients. At 6 months post treatment, 90.30% patients in the haplo-HSCT group and 18.78% patients in the IST group achieved normal blood routine (P < 0.0001). The time required to discontinue red blood cells and platelets transfusion in the IST group were longer than in the haplo-HSCT group (P < 0.0001). The estimated overall survival at 4 years was similar (80.1 ± 3.5% vs. 80.1 ± 3.0%, P = 0.726); the estimated failure-free survival (FFS) at 4 years was 77.8 ± 3.7% in the haplo-HSCT group and 48.0 ± 3.6% in the IST group (P < 0.0001). Patients treated with haplo-HSCT scored significantly better in the HRQoL than treated with IST (P < 0.0001). In the multivariate analysis, first-line haplo-HSCT was the favorable factor for FFS and HRQoL (P < 0.0001). These results suggest that first-line haplo-HSCT combined with UCB infusion might provide a better chance of success and HRQoL than first-line IST for SAA patients.

Monosomal karyotype is associated with poor outcomes in patients with Philadelphia chromosome-negative acute lymphoblastic leukemia receiving chemotherapy but not allogeneic hematopoietic stem cell transplantation

Monosomal karyotype (MK) is associated with poor prognosis in patients with myeloid neoplasms; however, its prognostic significance in Philadelphia chromosome-negative (Ph-negative) acute lymphoblastic leukemia (ALL) remains unclear. Data of 323 patients with Ph-negative ALL treated at Peking University People's Hospital were retrospectively analyzed. MK was identified in 49 (14.8%) patients. The patients with MK had lower hemoglobin levels (P = 0.026), lower platelet count (P = 0.032), higher percentages of blasts in the peripheral blood at diagnosis (P = 0.008), and higher percentages of high-risk karyotypes (P < 0.001) compared with those without MK. The complete remission (CR) rate and the minimal residual disease negativity rate were not significantly different between patients with and without MK. In the multivariate analysis, MK was identified as an independent factor associated with higher cumulative incidence of relapse (CIR) (hazard ratio (HR), 2.07; 95% confidence interval (CI), 1.02, 4.21; P = 0.043), shorter disease-free survival (DFS) (HR, 2.80; 95% CI, 1.20, 6.54; P = 0.017) and shorter overall survival (OS) (HR, 5.75; 95% CI, 2.07, 16.03; P = 0.001) in the chemotherapy cohort; however, MK had no impact on outcomes in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) cohort. Mantel-Byar analysis showed that allo-HSCT was associated with lower CIR (P < 0.001), longer DFS (P < 0.001), and longer OS (P < 0.001) in CR patients with MK. In conclusion, our study showed that MK was an independent predictor of poor outcomes in patients with Ph-negative ALL receiving chemotherapy but not allo-HSCT, and allo-HSCT could improve the outcomes of patients with MK.

Recommended prophylactic and management strategies for severe acute respiratory syndrome coronavirus 2 infection in transplant recipients

Since December 2019, increasing attention has been paid to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic in Wuhan, China. SARS-CoV-2 primarily invades the respiratory tract and lungs, leading to pneumonia and other systemic disorders. The effect of SARS-CoV-2 in transplant recipients has raised significant concerns, especially because there is a large population of transplant recipients in China. Based on the current epidemic situation, this study reviewed publications on this virus and coronavirus disease 2019 (COVID-19), analyzed common features of respiratory viral pneumonias, and presented the currently reported clinical characteristics of COVID-19 in transplant recipients to improve strategies regarding the diagnosis and treatment of COVID-19 in this special population.

Measurable residual disease of acute lymphoblastic leukemia in allograft settings: how to evaluate and intervene

INTRODUCTION

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a curable strategy for acute lymphoblastic leukemia (ALL), especially for adult cases. However, leukemia relapse after allograft restricts the improvement of transplant outcomes. Measurable residual disease (MRD) has been the strongest predictor for relapse after allo-HSCT, allowing MRD-directed preemptive therapy.

AREAS COVERED

This manuscript summarizes the detection of MRD in patients with ALL who undergo allo-HSCT, focusing the effects of positive pre-HSCT MRD and post-HSCT MRD on outcomes as well as MRD-directed interventions.

EXPERT OPINION

Except for MFC and RQ-PCR, other strategies, such as next-generation sequencing and RNAseq, have been developed for MRD determination. Negative effects of positive MRD peri-transplantation on outcomes of ALL patients were observed both in human leukocyte antigen (HLA)-matched sibling donor transplantation and in alternative donor transplantation. Advances have been made in determining the need for transplant according to MRD evaluation after induction or consolidation therapy. A number of approaches, including CAR-T-cell therapy, antibodies (blinatumomab, etc), targeted therapy (imatinib, etc), transplant donor selection, as well as donor lymphocyte infusion and interferon-α, have been successfully used or are promising for peri-transplantation MRD interventions. This progress could lead to the significant improvement of transplant outcomes for ALL patients.

Pre-transplant MRD negativity predicts favorable outcomes of CAR-T therapy followed by haploidentical HSCT for relapsed/refractory acute lymphoblastic leukemia: a multi-center retrospective study

Background

Consolidative allogeneic hematopoietic stem cell transplantation is a controversial option for patients with relapsed/refractory acute lymphoblastic leukemia after chimeric antigen receptor T cell (CAR-T) therapy. We performed a multicenter retrospective study to assess whether patients can benefit from haploidentical hematopoietic stem cell transplantation after CAR-T therapy.

Methods

A total of 122 patients after CAR-T therapy were enrolled, including 67 patients without subsequent transplantation (non-transplant group) and 55 patients with subsequent haploidentical hematopoietic stem cell transplantation (transplant group). Long-term outcome was assessed, as was its association with baseline patient characteristics.

Results

Compared with the non-transplant group, transplantation recipients had a higher 2-year overall survival (OS; 77.0% versus 36.4%; P < 0.001) and leukemia-free survival (LFS; 65.6% versus 32.8%; P < 0.001). Multivariate analysis showed that minimal residual disease (MRD) positivity at transplantation is an independent factor associated with poor LFS (P = 0.005), OS (P = 0.035), and high cumulative incidence rate of relapse (P = 0.045). Pre-transplant MRD-negative recipients (MRD− group) had a lower cumulative incidence of relapse (17.3%) than those in the non-transplant group (67.2%; P < 0.001) and pre-transplant MRD-positive recipients (MRD+ group) (65.8%; P = 0.006). The cumulative incidence of relapse in MRD+ and non-transplant groups did not differ significantly (P = 0.139). The 2-year LFS in the non-transplant, MRD+, and MRD− groups was 32.8%, 27.6%, and 76.1%, respectively. The MRD− group had a higher LFS than the non-transplantation group (P < 0.001) and MRD+ group (P = 0.007), whereas the LFS in the MRD+ and non-transplant groups did not differ significantly (P = 0.305). The 2-year OS of the MRD− group was higher than that of the non-transplant group (83.3% versus 36.4%; P < 0.001) but did not differ from that of the MRD+ group (83.3% versus 62.7%; P = 0.069). The OS in the non-transplant and MRD+ groups did not differ significantly (P = 0.231).

Conclusion

Haploidentical hematopoietic stem cell transplantation with pre-transplant MRD negativity after CAR-T therapy could greatly improve LFS and OS in patients with relapsed/refractory acute lymphoblastic leukemia.

Trial registration

The study was registered in the Chinese clinical trial registry (ChiCTR1900023957).

Incidence, Risk Factors, and Outcomes of Primary Prolonged Isolated Thrombocytopenia after Haploidentical Hematopoietic Stem Cell Transplant

The aim of this study was to evaluate the incidence, risk factors, and outcomes of primary prolonged isolated thrombocytopenia (PT) after haploidentical hematopoietic stem cell transplant (haplo-HSCT). We retrospectively analyzed patients who received haplo-HSCT for various hematologic malignancies at Peking University Institute of Hematology between January 2015 and December 2016. Of the 918 patients, 93 (10.1%) developed primary PT. We designed a propensity score method-based study. For each primary PT patient control subjects (1:3) were selected using a propensity score-matching method. A total of 372 recipients were enrolled in the study: 93 in the PT group and 279 in the control group. Multivariate analysis showed that age older than 25 years (P = .002), median mononuclear cells (P = .000), median CD34⁺ counts (P = .003), history of grades II to IV acute graft-versus-host disease (GVHD; P = .000), and Epstein-Barr virus (EBV) infection after haplo-HSCT (P = .016) were independent risk factors for primary PT. Primary PT was significantly associated with higher transplant-related mortality (TRM; P < .001), inferior overall survival (P = .001), and disease-free survival (P = .005). In conclusion, the incidence of primary PT after haplo-HSCT was 10.1%. Primary PT was associated with poorer survival and higher TRM along with older age, grades II to IV acute GVHD, and EBV infection after haplo-HSCT.

Mechanisms and rejuvenation strategies for aged hematopoietic stem cells

Hematopoietic stem cell (HSC) aging, which is accompanied by reduced self-renewal ability, impaired homing, myeloid-biased differentiation, and other defects in hematopoietic reconstitution function, is a hot topic in stem cell research. Although the number of HSCs increases with age in both mice and humans, the increase cannot compensate for the defects of aged HSCs. Many studies have been performed from various perspectives to illustrate the potential mechanisms of HSC aging; however, the detailed molecular mechanisms remain unclear, blocking further exploration of aged HSC rejuvenation. To determine how aged HSC defects occur, we provide an overview of differences in the hallmarks, signaling pathways, and epigenetics of young and aged HSCs as well as of the bone marrow niche wherein HSCs reside. Notably, we summarize the very recent studies which dissect HSC aging at the single-cell level. Furthermore, we review the promising strategies for rejuvenating aged HSC functions. Considering that the incidence of many hematological malignancies is strongly associated with age, our HSC aging review delineates the association between functional changes and molecular mechanisms and may have significant clinical relevance.

Alternative donor peripheral blood stem cell transplantation for the treatment of high-risk refractory and/or relapsed childhood acute leukemia: a randomized trial

Background

The high-risk refractory and/or relapsed (R/R) childhood acute leukemia prognosis is poor, and allogeneic stem cell transplantation (allo-HSCT) is the most prudent treatment modality. However, there are limited matched sibling donors (MSDs), and alternative donors (ADs) are the main source for allo-HSCT. Thus, we evaluated the clinical efficacy of AD peripheral allo-HSCT for treating high-risk R/R childhood acute leukemia.

Methods

We assessed 111 children who underwent allo-HSCT at the Affiliated Cancer Hospital of Zhengzhou University between October 2006 and July 2019. The patients were divided in the MSD and AD groups, and their clinical characteristics, complications, and survival rates were compared.

Results

The cumulative incidences of Epstein–Barr virus and cytomegalovirus infections were significantly higher in the AD than in the MSD group (P < 0.001); however, the recurrence and mortality rates were significantly higher in the MSD than in the AD group (P < 0.05). Furthermore, the 5-year disease-free (DFS) (65.2% vs. 43.3%, P = 0.033) and overall survival (OS) rates (71.6% vs. 53.8%, P = 0.053) were significantly higher in the AD than in the MSD group. In the AD group, the grade II–IV acute graft-versus-host disease (aGVHD), donor-recipient ABO compatibility, conditioning regimen, and CMV infection affected the 5-year OS. The grade II–IV aGVHD also affected the 5-year DFS; however, only the donor-recipient ABO compatibility affected the 5-year DFS. The donor MSD (HR: 2.035, 95% confidence interval [CI] 1.057–3.920, P = 0.034) and the grade II–IV aGVHD (HR: 2.914, 95% CI 1.261–6.736, P = 0.012) affected the 5-year DFS of childhood acute leukemia after allo-HSCT, and the grade II–IV aGVHD (HR: 3.016, 95% CI 1.217–7.473, P = 0.017) affected the 5-year OS. Moreover, the donor source (HR: 2.836, 95% CI 1.179–6.823, P = 0.020) and grade II–IV aGVHD (HR: 3.731, 95% CI 1.332–10.454, P = 0.012) were independent predictors of the 5-year DFS, while the latter (HR: 3.524, 95% CI 1.310–10.988, P = 0.030) was an independent predictor of the 5-year OS.

Conclusions

AD-PBSCT was effective for high-risk R/R childhood leukemia and may have better clinical outcomes than MSD-PBSCT; thus, it can be used as first-line treatment for high-risk R/R childhood leukemia.

Haploidentical donor is preferred over matched sibling donor for pre-transplantation MRD positive ALL: a phase 3 genetically randomized study

Background

Previous reports suggest a benefit associated with haploidentical donor transplantation (HIDT) compared to matched sibling donor transplantation (MSDT) in certain contexts, and the choice of optimal candidates warrants further investigation.

Methods

We designed a prospective genetically randomized study to evaluate donor options between acute lymphoblastic leukemia (ALL) patients positive for measurable residual disease (MRD) pre-transplantation who underwent HIDT (n = 169) or MSDT (n = 39).

Results

The cumulative incidence of positive MRD post-transplantation was 26% (95% CI, 19–33%) and 44% (95% CI, 28–60%) for HIDT and MSDT, respectively (P = 0.043). Compared to the HIDT cohort, the MSDT cohort had a higher 3-year cumulative incidence of relapse (CIR; 47%, 95% CI, 31–63% vs. 23%, 95% CI, 17–29%; P = 0.006) and lower 3-year probability of leukemia-free survival (LFS; 43%, 95% CI, 27–59% vs. 65%, 95% CI, 58–72%; P = 0.023) and overall survival (OS; 46%, 95% CI, 30–62% vs. 68%, 95% CI, 61–75%; P = 0.039), without a difference in non-relapse-mortality (10%, 95% CI, 1–19% vs. 11%, 95% CI, 6–16%; P = 0.845). Multivariate analysis showed that HIDT is associated with a low CIR (HR = 0.364; 95% CI, 0.202–0.655; P = 0.001) and better LFS (HR = 0.414; 95% CI, 0.246–0.695; P = 0.001) and OS (HR = 0.380; 95% CI, 0.220–0.656; P = 0.001).

Conclusions

HIDT is better than MSDT in view of favorable anti-leukemia activity for patients with pre-transplantation MRD positive ALL. The current study paves the way to determine that haploidentical donors are the preferred choice regardless of available matched sibling donors in a subgroup population.

Trial registration

ClinicalTrials.gov Identifier: NCT02185261. Registered July 9, 2014. https://clinicaltrials.gov/ct2/show/NCT02185261?term=NCT02185261&draw=2&rank=1.

Combination of haploidentical haematopoietic stem cell transplantation with an unrelated cord-blood unit in patients with severe aplastic anemia: a report of 146 cases

We analyzed the outcomes of 146 severe aplastic anemia (SAA) patients who received a combination of haploidentical haematopoietic stem cell transplantation (haplo-HSCT) and an unrelated cord-blood (UCB) unit between September 2011 and December 2017. One hundred and seventeen patients underwent transplantation as first-line therapy. Seven patients experienced early mortality, and among the evaluable 139 patients, one patient experienced primary graft failure (GF), while the other 138 patients achieved successful haploidentical donor engraftment; additionally, three patients experienced secondary GF. Six patients demonstrated delayed platelet recovery, and three patients demonstrated platelet GF. The median time for myeloid and platelet engraftment was 11 (range: 9-28) days and 15 (range: 9-330) days, respectively. With a median follow-up of 40 (range: 18-93) months, the cumulative incidences were 31.43% and 10.00% for grades II-IV and grades III-IV acute graft-versus-host disease (GVHD), respectively. The cumulative incidences of chronic GVHD (cGVHD) and moderate-severe cGVHD were 36.23% and 11.71%, respectively. There was no patient relapse. The probabilities of 4-year overall survival and GVHD-free, failure-free survival were 81.4 ± 3.3% and 69.2 ± 3.9%, respectively. These encouraging preliminary results indicated that haplo-HSCT combined with the infusion of UCB is a feasible choice for SAA patients without matched donors.

Haploidentical versus HLA-matched sibling transplantation for refractory acute leukemia undergoing sequential intensified conditioning followed by DLI: an analysis from two prospective data

BACKGROUND

Compared with HLA-matched sibling donor (MSD) transplant, the outcomes of haploidentical donor (HID) transplant for refractory acute leukemia need to be further explored. In this study, we compared the outcomes of HID with MSD for refractory acute leukemia.

PATIENTS AND METHODS

This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Two hundred and seventy-eight patients with refractory acute leukemia were enrolled in this study, including 119 in HID group and 132 in MSD group. Sequential intensified conditioning was employed in all patients, and donor lymphocyte infusion (DLI) was administered in patients in the absence of active GVHD and according to minimal residual disease (MRD) from day + 60 post-transplantation for preventing relapse.

RESULTS

The complete remission of leukemia by day + 30 post-transplant were 94% and 93%, respectively, in HID and MSD groups (p = .802). The 1-year incidence of grades II-IV acute GVHD was 62% and 54% (p = .025), and 3-year incidence of chronic GVHD was 55% and 55% (p = .789), respectively, in two groups. HID transplant had lower incidence of first episode of MRD positivity and relapse than MSD transplant (28% vs 45%, p = .006; 26% vs 38%, p = .034). There was higher infection-related mortality in HID than MSD (8% vs 2%, p = .049) within the first 100 days' post-transplant. The 5-year overall survival was 46% and 42% (p = .832), respectively; the 5-year disease-free survival was 43% and 39% (p = .665), in HID and MSD groups, respectively.

CONCLUSIONS

HID transplant has lower relapse, but higher infection-related mortality and similar survival rates in refractory acute leukemia by the strategy of sequential intensified conditioning followed by DLI compared with MSD transplant.

[Risk factors analysis for steroid-resistant acute graft versus host disease after haploidentical hematopoietic stem cell transplantation]

目的

分析单倍型造血干细胞移植（haplo-HSCT）后糖皮质激素耐药急性移植物抗宿主病（GVHD）的危险因素。

方法

回顾性分析2010年1月至2011年12月在北京大学血液病研究所接受haplo-HSCT后并发急性GVHD的成人急性髓系白血病/骨髓增生异常综合征患者的临床资料。

结果

共有85例急性GVHD患者纳入研究，男55例，女30例，中位年龄30（19~67）岁。糖皮质激素治疗后达到完全缓解（CR）53例（62.4%），部分缓解（PR）6例（7.1%），未缓解（NR）26例（30.6%）。Ⅰ/Ⅱ、Ⅲ/Ⅳ度急性GVHD组糖皮质激素治疗的CR率分别为66.2%（51/77）、25.0%（2/8）（χ²=3.639，P=0.048）；累及1个、2个靶器官急性GVHD组糖皮质激素治疗的CR率分别为77.4%（48/62）、21.7%（5/23）（χ²=22.157，P<0.001）；明尼苏达危险度积分标危、高危组糖皮质激素治疗的CR率分别为67.5%（52/77）、12.5%（1/8）（χ²=7.153，P=0.004）。单因素和多因素分析均显示明尼苏达危险度积分高危和移植物单个核细胞量≥8.33×10⁸/kg是发生糖皮质激素耐药急性GVHD的独立危险因素。明尼苏达积分标危组（77例）、高危组（8例）移植后22个月总生存率分别为（90.3±3.8）%、（75.0±15.3）%（χ²=2.831，P=0.092）；糖皮质激素治疗CR组（53例）、非CR组（32例）移植后22个月总生存率分别为（95.2±3.4）%、（78.6±7.9）%（χ²=5.287，P=0.021）。

结论

明尼苏达危险度积分和移植物单个核细胞数可以预测haplo-HSCT后糖皮质激素耐药的急性GVHD。

Autophagy in endothelial cells regulates their haematopoiesis-supporting ability

Background

Endothelial cells (ECs) function as an instructive platform to support haematopoietic stem cell (HSC) homeostasis. Our recent studies found that impaired bone marrow (BM) ECs are responsible for the defective haematopoiesis in patients with poor graft function (PGF), which is characterised by pancytopenia post-allotransplant. Although activated autophagy was reported to benefit ECs, whether EC autophagy plays a critical role in supporting HSCs and its effect on PGF patients post-allotransplant remain unclear.

Methods

To evaluate whether the autophagy status of ECs modulates their ability to support haematopoiesis, human umbilical vein endothelial cells (HUVECs) and primary BM ECs derived from healthy donors were subjected to knockdown or overexpression of Beclin-1 (an autophagy-related protein). Moreover, BM ECs derived from PGF patients were studied.

Findings

Beclin-1 knockdown significantly reduced the haematopoiesis-supporting ability of ECs by suppressing autophagy, which could be restored by activating autophagy via Beclin-1 upregulation. Moreover, autophagy positively regulated haematopoiesis-related genes in HUVECs. Subsequently, a prospective case-control study demonstrated that defective autophagy reduced Beclin-1 expression and the colony-forming unit (CFU) plating efficiency in BM ECs from PGF patients compared to matched patients with good graft function. Rapamycin, an autophagy activator, quantitatively and functionally improved BM ECs from PGF patients in vitro and enhanced their ability to support HSCs by activating the Beclin-1 pathway.

Interpretation

Our results suggest that the autophagy status of ECs modulates their ability to support haematopoiesis by regulating the Beclin-1 pathway. Defective autophagy in BM ECs may be involved in the pathogenesis of PGF post-allotransplant. Rapamycin provides a promising therapeutic approach for PGF patients.

Funding

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Comparable survival outcome between transplantation from haploidentical donor and matched related donor or unrelated donor for severe aplastic anemia patients aged 40 years and older: A retrospective multicenter cohort study

This retrospective multicenter cohort study aimed to compare the outcome of haploidentical hematopoietic stem cell transplantation (HID-HSCT) with matched sibling donor (MSD) and unrelated donor (URD) transplantation in severe aplastic anemia (SAA) patients 40 years of age and older. With a median follow-up time of 17.6 months, 85 consecutive patients were enrolled in the study, and the median patient age was 45 years (40, 58). The cumulative engraftment rates of neutrophil and platelet were 98.8 ± 0.0% and 92.9 ± 0.1%. The cumulative incidences of Grade 2-4 acute graft-versus-host disease (aGvHD) and chronic graft-versus-host disease (cGvHD) at 3 years were 14.1 ± 0.1% and 17.3 ± 0.2%. The 3-year estimated overall survival (OS) and failure-free survival (FFS) were 91.2 ± 3.2% and 89.7 ± 3.5%. In multivariate analysis, the only factor associated with inferior survival was an ECOG score ≥2. HID-HSCT was associated with a higher incidence of GvHD, but the difference of 3-year estimated OS between HID group and the other two cohorts was not significant (86.7 ± 6.4% for HID vs 92.1% ± 4.4% for MSD and 100% for URD, P = .481). HID-HSCT might be a feasible alternative option for selected SAA patients aged 40 years and older without a matched donor.

Impact of prophylactic/preemptive donor lymphocyte infusion and intensified conditioning for relapsed/refractory leukemia: a real-world study

Prophylactic/preemptive donor lymphocyte infusion (p/pDLI) and intensified conditioning have shown promising results in experimental studies of refractory/relapsed acute leukemia (RRAL), but real-world data remain scarce. We conducted a multicenter, population-based analysis of 932 consecutive patients. The three-year leukemia-free survival (LFS) rates were 56% for patients receiving both p/pDLI and intensified myeloablative conditioning (MAC) (intenseMAC) and 30% for those who received neither therapy per landmark analysis. Multivariable analyses were run separately for acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), and p/pDLI treatment was linked to significantly higher LFS than non-DLI for both AML and ALL patients without increasing the nonrelapse mortality. IntenseMAC was associated with significantly lower relapse and higher LFS than nonintensified MAC despite higher nonrelapse mortality rates in ALL, while there was no impact of intenseMAC observed in AML. p/pDLI achieved superior outcomes in both matched-sibling donor (MSD) and haploidentical donor transplantation, while intenseMAC only influenced MSD outcomes. Data suggest that RRAL patients receiving "total therapy" by way of p/pDLI and intensified conditioning treatment have an improved chance for LFS, with p/pDLI being safer with a more extensive impact relative to intenseMAC. Patients with RRAL can tolerate both interventions and achieve a reasonable outcome.

THBS1 Is a Novel Serum Prognostic Factors of Acute Myeloid Leukemia

Dysregulation of cytokines and growth factors is a general feature of tumor microenvironment, and unraveling the expression spectrum of cytokine and growth factor in niche is of utmost importance. Here, we evaluated cytokine profiling of bone marrow serum samples in AML patients and healthy controls. Protein expression profiling of serum from nine AML patients and five healthy controls was obtained using a biotinylated antibody chip. A total of 507 cytokines and growth factors were analyzed. Compared with healthy people, AML patients expressed 31 signature proteins, among which, 27 were significantly higher expressed and 4 proteins were lower. When patients were divided into favorable and poor prognosis, 12 signature proteins were significantly differentially expressed between these two groups. Furthermore, in order to identify the accuracy of cytokine expression profiles, we verified and analyzed the expression of THBS1 (Thrombospondin 1) in 116 patients and 9 healthy people. We found that THBS1 was lowly expressed in AML patients, which might be induced by promoter methylation, and patients with low THBS1 possessed shorter survivor time. Our data indicated that we successfully unveil differentially expressed proteins in AML patients using a biotinylated antibody chip; among them, THBS1 may be a potential therapeutic target for AML patients' treatment.

Influence of the degree of donor bone marrow hyperplasia on patient clinical outcomes after allogeneic hematopoietic stem cell transplantation

This study evaluated the influence of the degree of donor bone marrow (BM) hyperplasia on patient clinical outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Twelve patients received allo-HSCT from hypoplastic BM donors between January 2010 and December 2017. Forty-eight patients whose donors demonstrated BM hyperplasia were selected using a propensity score matching method (1:4). Primary graft failure including poor graft function and graft rejection did not occur in two groups. In BM hypoplasia and hyperplasia groups, the cumulative incidence (CI) of neutrophil engraftment at day 28 (91.7% vs. 93.8%, P=0.75), platelet engraftment at day 150 (83.3% vs. 93.8%, P=0.48), the median time to myeloid engraftment (14 days vs. 14 days, P=0.85) and platelet engraftment (14 days vs. 14 days, P=0.85) were comparable. The 3-year progression-free survival, overall survival, CI of non-relapse mortality and relapse were 67.8% vs. 71.7% (P=0.98), 69.8% vs. 77.8% (P=0.69), 18.5% vs. 13.6% (P=0.66), and 10.2% vs. 10.4% (P=0.82), respectively. In multivariate analysis, donor BM hypoplasia did not affect patient clinical outcomes after allo-HSCT. If patients have no other suitable donor, a donor with BM hypoplasia can be used for patients receiving allo-HSCT if the donor Complete Blood Count and other examinations are normal.

Haploidentical transplantation might have superior graft-versus-leukemia effect than HLA-matched sibling transplantation for high-risk acute myeloid leukemia in first complete remission: a prospective multicentre cohort study

This study aimed to investigate graft-versus-leukemia (GVL) of haploidentical donor (HID) compared with HLA-matched sibling donor (MSD) for high-risk acute myeloid leukemia (H-AML) in first complete remission (CR1). One hundred and eighty-nine patients with H-AML in CR1 were enrolled in this multicentre prospective cohort study. Patients were assigned to groups transplanted with HID (n = 83) or MSD (n = 106) based on donor availability (biological randomization). The primary endpoint was the incidence of MRD positivity posttransplantation (post-MRD+). All post-MRD+ patients received preemptive interventions. The cumulative incidences of post-MRD+ were 18 and 42% in HID and MSD groups, respectively, (p < 0.001). Fifty-two patients received preemptive DLI, including 13 (16%) in HID and 39 cases (37%) in MSD groups (p = 0.001). Among HID and MSD groups, the 3-year cumulative incidence of relapse were 14 and 24% (p = 0.101); the 3-year cumulative incidence of treatment-related mortality were 15 and 10% (p = 0.368); the 3-year overall survival rates were 72 and 68% (p = 0.687); the 3-year disease-free-survival were 71 and 66% (p = 0.579); the 3-year graft-versus-host disease and relapse free survival were 63 and 43% (p = 0.035), respectively. HID might have a stronger GVL than MSD in H-AML patients. HID transplantation as postremission therapy should be recommended as one of the optimal choices for H-AML patients in CR1.

Decitabine-Containing Conditioning Regimen for Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Intermediate- and High-Risk Myelodysplastic Syndrome/Acute Myeloid Leukemia: Potential Decrease in the Incidence of Acute Graft versus Host Disease

Purpose

To evaluate the role of Decitabine in the allo-HSCT conditioning regimen for intermediate- and high-risk patients with MDS or AML.

Patients and methods

Retrospective analysis of data pertaining to 76 intermediate- and high-risk patients with MDS or AML who underwent allo-HSCT between December 2005 and June 2018 at the Peking University First Hospital. Forty patients received Decitabine-containing conditioning regimen before transplantation, while thirty-six patients received regimen without Decitabine.

Results

Over a median follow-up of 40 months (range, 1 to 155), the cumulative incidence of grade II to IV acute graft versus host disease was 12.4% [95% confidence interval (CI) 4.9–30.9%] in the Decitabine group and 41.5% (95% CI 28.1–61.2%) in the non-Decitabine group (P=0.005). On multivariate analysis, Decitabine-containing conditioning regimen was found to protect against grade II to IV aGVHD (HR=0.279, 95% CI 0.102–0.765, P=0.013). Incidence of respiratory infection in the Decitabine and non-Decitabine groups was 22.5% and 52.78%, respectively (P=0.012). No significant between-group difference was observed with respect to 3-year OS, DFS, or RR (P=0.980, 0.959, and 0.573, respectively), while the median relapse time was longer in the Decitabine group [7 months (range, 2–12) versus 3 months (range, 2–4), P=0.171]. Decitabine-containing conditioning showed a tendency for lower relapse rate among higher risk patients, as assessed by IPSS R; however, the between-group difference was not statistically significant (P=0.085).

Conclusion

Inclusion of Decitabine in the conditioning regimen for allo-HSCT in intermediate- and high-risk patients may lower the incidence of aGVHD and respiratory infections, and contribute to longer median relapse time.

Subgroup Analysis Can Optimize the Relapse-Prediction Cutoff Value for WT1 Expression After Allogeneic Hematologic Stem Cell Transplantation in Acute Myeloid Leukemia

High WT1 expression after allogeneic hematologic stem cell transplantation (allo-HSCT) can strongly predict relapse in acute myeloid leukemia (AML). However, the cutoff values obtained have been inconsistent. Precise cutoff values may be optimized through subtype analysis; the RUNX1-RUNX1T1 fusion transcript provides an ideal reference. RUNX1-RUNX1T1 and WT1 transcript levels were simultaneously measured in 1299 bone marrow samples serially collected from 176 t(8;21) AML patients after allo-HSCT. The upper limit of the normal bone marrow WT1 level was 0.6%, which we previously reported to be the cutoff value for significant relapse prediction in AML as a whole. WT1 cutoff values of 0.6%, 1.2%, and 1.8% significantly differentiated patients in relapse after allo-HSCT. Nonetheless, patients with WT1 levels of 0.6% to 1.2% and those with levels of >1.2% and 1.8% after HSCT had rates of cumulative incidence of relapse similar to those with a continuous WT1 level of ≤0.6%, and both were significantly lower than that in patients with a WT1 level of >1.8%. WT1 expression was significantly related to RUNX1-RUNX1T1 transcript levels at WT1 levels of >1.8% but not at levels of 0.6% to 1.2% or >1.2% to 1.8%. Therefore, subgroup analysis can optimize the relapse-prediction cutoff value of WT1 expression. A cutoff level of 1.8% more accurately differentiates t(8;21) AML patients in relapse after allo-HSCT than does a cutoff level of 0.6%.

Combination of HLA-Matched Sibling Allogeneic Hematopoietic Stem Cell Transplantation With Unrelated Cord Blood Unit in Patients Aged 35 to 50 Years With Severe Aplastic Anemia: Preliminary Summary of a Single-Arm Trial

This study reports a single-arm trial in the interim phase in 4 patients with median age of 40.5 years who have undergone combined HLA-matched sibling donor (MSD) stem cell graft and an unrelated cord blood (UCB) unit for the treatment of severe aplastic anemia (SAA). The median time was 10 days for neutrophil engraftment (9-18 days) and 17 days for platelets (12-24 days). Median follow-up of 22 months (ranging from 16 to 29 months) showed survival of the 4 patients with complete hematological response. Acute graft-vs-host disease (GVHD) (grade II) occurred only in 1 patient, yet chronic GVHD was free. One patient showed a pattern of transient MSD graft followed by dominant UCB chimerism, and another 1 achieved mixed chimerism in the first 6 months after allogeneic hematopoietic stem cell transplantation (allo-HSCT) then evolved to a stable MSD graft. The other 2 patients sustained a full MSD graft during the post-HSCT period. Nevertheless, none of the patients developed primary and secondary graft failure up to the final follow-up. Although this is a small cohort, the dual transplantation combining HLA-matched sibling allogeneic hematopoietic stem cell transplantation with unrelated cord blood unit may deserve further exploration for treatment of SAA patients aged 35 to 50 years old.

Lower T cell inhibitory receptor level in mononuclear cells from cord blood compared with peripheral blood

T cell inhibitory receptors play important role in maintaining T cell homeostasis. The feature of such negative costimulator signal transduction pathway in cord blood (CB) T cells remains unclear. In this study, the expression levels of T cell inhibitory receptors including programmed death-1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), T cell immunoglobulin mucin-3 (Tim-3), lymphocyte activation gene-3 (LAG-3) and B and T lymphocyte attenuator (BTLA) were characterized in CB and compared with peripheral blood (PB). Significant lower expression of PD-1, CTLA-4, LAG-3 and BTLA was found in CB, while similar expression level of Tim-3 was showed between CB and PB. Together, different expression pattern of such T cell inhibitory receptor in CB is worthy to further discuss their role on immune response when CB is used in cord blood stem cell transplantation as well as allogeneic chimeric antigen receptor T-cell producing.

Improved survival after offspring donor transplant compared with older aged-matched siblings for older leukaemia patients

Donor selection for older leukaemia patients undergoing haematopoietic cell transplant (HCT) is not well defined: outcomes might be improved with a younger offspring donor rather than an older human leukocyte antigen (HLA)-matched sibling donor (MSD). We extended our multicentre dataset. A total of 185 acute leukaemia patients (≥ 50 years) transplanted in first complete remission who received HCT from offspring (n = 62) or MSD (n = 123) were included. A 1:1 ratio matched-pair analysis was performed. We were able to match 54 offspring with 54 MSD patients. Outcomes were compared between the two matched-pair groups. The cumulative incidence of grade II/IV acute graft-versus-host disease (GVHD) (26% vs. 35%; P = 0·23) and chronic GVHD (37% vs. 24%; P = 0·19) was comparable between groups (MSD vs. offspring). The lower three-year transplant-related mortality (9% vs. 26%; P = 0·023) and relapse incidence (6% vs. 17%; P = 0·066) resulted in higher overall survival (85% vs. 58%; P = 0·003) and leukaemia-free survival (LFS) (85% vs. 56%; P = 0·001) in offspring HCT compared with that in MSD HCT. These data might favour a young offspring over an older MSD in patients >50 years. The current analyses confirm that non-HLA donor characteristics, such as kinship and donor age, rather than HLA disparity, predominantly influence survival in older acute leukaemia patients.

Child with Wiskott–Aldrich syndrome underwent atypical immune reconstruction after umbilical cord blood transplantation: A case report

BACKGROUND

Timely reconstitution of a donor-derived immune system is important for recovery and long-term survival of patients after allogeneic hematopoietic stem cell transplantation (HSCT). We describe a case of Wiskott–Aldrich syndrome (WAS) treated by umbilical cord blood transplantation (UCBT) with atypical immune reconstruction.

CASE SUMMARY

A 1-year-old Chinese male infant was diagnosed with WAS. WAS gene sequencing identified the mutation c.777 + 1G>A (IVS8). On August 8, 2017, he was admitted to our hospital for HSCT. We selected an unrelated Human leukocyte antigen 6/10-matched donor for UCBT. After HSCT, the immune reconstitution process was atypical, the lymphocytes reached 0.5 × 10⁹/L on day 23, and the neutrophils reached 0.5 × 10⁹/L on day 34. The patient’s recovery throughout the year was good.

CONCLUSION

An increase in lymphocytes (especially T cells) earlier than granulocytes may be a marker of a good prognosis in UCBT.

Basiliximab as Treatment for Steroid-Refractory Acute Graft-versus-Host Disease in Pediatric Patients after Haploidentical Hematopoietic Stem Cell Transplantation

Basiliximab has been used successfully as a second-line treatment for steroid-refractory (SR) acute graft-versus-host disease (aGVHD) in adult patients after haploidentical hematopoietic stem cell transplant (haplo-HSCT) but has not been studied separately in the pediatric setting. We retrospectively reviewed 100 pediatric patients after haplo-HSCT receiving basiliximab for grades II (57%), III (27%), and IV (16%) SR aGVHD between January 2015 and December 2017. The median number of basiliximab doses was 4 (range, 2 to 9). The day 28 overall response rate was 85%, with complete response in 74% of patients, partial response in 11% of patients, and no response in 15% of patients. The day 28 overall response rates were 94.6% in skin SR aGVHD, 81.6% in gut SR aGVHD, and 66.7% in liver SR aGVHD. Infectious complications included bacterial infection (11%), presumed or documented fungal infections (7%), cytomegalovirus viremia (53%), Epstein-Barr virus viremia (11%), human herpesvirus-6 viremia (7%), and herpes simplex virus viremia (1%). The 3-year overall survival, disease-free survival, nonrelapse mortality, and relapse rates between responders and nonresponders were 81.3% versus 46.7% (P < .001), 79.0% versus 46.7% (P = .001), 6.1% versus 33.3% (P < .001), and 14.9% versus 20.0% (P = .46), respectively. We conclude that basiliximab is an effective second-line agent for pediatric patients with SR aGVHD after haplo-HSCT, particularly for skin SR aGVHD.

Risk factors for chronic graft-versus-host disease after anti-thymocyte globulin-based haploidentical hematopoietic stem cell transplantation in acute myeloid leukemia

Chronic graft-versus-host disease (cGVHD) is a major complication following unmanipulated haploidentical hematopoietic stem cell transplantation (haplo-HSCT). We aimed to identify the risk factors for cGVHD in patients who underwent anti-thymocyte globulin-based haplo-HSCT for acute myeloid leukemia (n = 280). The diagnosis of cGVHD was in accordance with the National Institutes of Health consensus criteria. A total of 169 patients suffered from cGVHD. The patients who had 3 loci mismatched had a higher 8-year incidence of cGVHD (total, 66.0% vs. 53.7%, P = 0.031; moderate to severe, 42.4% vs. 30.1%, P = 0.036) than the patients who had 1 to 2 loci mismatched. The patients who had maternal donors had a higher 8-year incidence of moderate to severe cGVHD (49.2% vs. 32.9%, P = 0.024) compared with the patients who had other donors. The patients who had grades III to IV acute GVHD (aGVHD) had higher 8-year incidence of cGVHD (total, 88.0% vs. 50.4%, P < 0.001; moderate to severe, 68.0% vs. 27.0%, P < 0.001) compared with the patients without aGVHD. In multivariate analysis, grades III to IV aGVHD was the only independent risk factor for cGVHD. Thus, further interventions should be considered in patients with severe aGVHD to prevent cGVHD.

Low-dose post-transplant cyclophosphamide and anti-thymocyte globulin as an effective strategy for GVHD prevention in haploidentical patients

BACKGROUND

Low-dose post-transplant cyclophosphamide (PTCy) in conjunction with anti-thymocyte globulin (ATG) appears as a potentially effective graft-versus-host disease (GVHD) prevention strategy in haploidentical hematopoietic cell transplant (haplo-HCT). Our study aims to assess the efficacy of this regimen.

METHODS

We extended our prospective study in patients treated with low-dose PTCy (14.5 mg/kg on days 3 and 4) in ATG/granulocyte colony-stimulating factor (G-CSF)-based regimen and compared the results to the contemporary cohort of patients without low-dose PTCy (ATG cohort). Both study cohort and control are transplanted from maternal donor or collateral relatives.

RESULTS

We identified 239 consecutive patients (ATG-PTCy cohort = 114; ATG cohort = 125). All patients but one in ATG cohort achieved myeloid engraftment by day 30 post-HCT. We found that both the cumulative incidence of 100-day grade III-IV aGvHD and non-relapse-mortality (NRM) in the ATG-PTCy cohort was significantly reduced than that in the ATG group (5% vs 18%; P = 0.003; and 6% vs 15%; P= 0.045); the 2-year cumulative incidences of relapse and overall survival were comparable between the two cohorts (13% vs 14%; P = 0.62; and 83% vs 77%; P = 0.18, respectively). Furthermore, GVHD-free, relapse-free survival (GRFS) was significantly improved in the ATG-PTCy arm (63% vs 48%; P = 0.039). In multivariate analysis, the joint treatment resulted in lower grade II-IV acute GVHD (HR 0.58; P = 0.036), grade III-IV aGvHD (HR 0.28; P = 0.006), chronic GVHD (HR 0.60; P = 0.047), NRM (HR 0.26; P = 0.014), and higher GRFS (HR 0.59; P = 0.021) but slower myeloid and platelet recovery (HR 0.29 and 0.30; both P < 0.001).

CONCLUSIONS

These results suggested that ATG/PTCy (low-dose) can reduce both acute and chronic GVHD as compared with standard ATG-based prophylaxis using maternal donor or collateral relatives at particular high GVHD risk.

Comparison of the clinical outcomes of hematologic malignancies after myeloablative haploidentical transplantation with G-CSF/ATG and posttransplant cyclophosphamide: results from the Chinese Bone Marrow Transplantation Registry Group (CBMTRG)

This study compared G-CSF/ATG and PTCy in myeloablative haploidentical hematopoietic stem cell transplantation (haplo-HSCT) for hematologic malignancies between January 2013 and March 2018 reporting to the Chinese Bone Marrow Transplantation Registry Group (CBMTRG). For each PTCy, G-CSF/ATG subjects (1:4) were selected using the nested case-pair method. In total, 220 patients including 176 in G-CSF/ATG group and 44 in PTCy group were analyzed. The incidences of 30-day neutrophil engraftment (88.6% vs. 96.6%, P=0.001), 90-day platelet engraftment (84.1% vs. 94.2%, P=0.04), the median time to neutrophil engraftment (17 days vs. 12 days, P=0.000) and platelet engraftment (22 days vs. 17 days, P=0.001) were significantly inferior in PTCy group. The incidences of grades 2-4 and 3-4 acute graft-versus-host disease (GVHD), chronic GVHD and severe chronic GVHD were comparable. Among G-CSF/ATG and PTCy groups, the 3-year progression-free survival, overall survival, cumulative incidences of nonrelapse mortality and relapse was 74.3% vs. 61% (P=0.045), 78.3% vs. 65.2% (P=0.039), 12% vs. 27.3% (P=0.008), and 14.9% vs. 11.7% (P=0.61), respectively. G-CSF/ATG can achieve better engraftment, PFS and OS, and lower incidence of NRM compared to PTCy in myeloablative haplo-HSCT for hematologic malignancies.

[Minimal residual disease in adults with Philadelphia chromosome negative acute lymphoblastic leukemia in high-risk]

Objective: To explore the significance of minimal residual disease (MRD) in predicting prognosis and guiding therapy of adults with Philadelphia-chromosome negative acute lymphoblastic leukemia (Ph(-) ALL) in high-risk. Methods: Data of newly diagnosed adults with Ph(-) ALL in high-risk who achieved CR were reviewed. Variables associated with outcome were identified by COX regression model and Landmark analysis. Results: A total of 177 patients, 99 (56%) cases male with a median age of 40 years (range, 16-65 years) were included in this study. Of them, 95 (54%) patients received allo-HSCT in CR(1). Multivariate analyses showed that MRD negativity after the first cycle of consolidation (HR=0.52, 95%CI 0.30-0.89, P=0.017) and achieving CR within 4 weeks (HR=0.43, 95%CI 0.24-0.79, P=0.006) were the factors significantly-associated with longer DFS, and allo-HSCT was associated with both longer DFS (HR=0.13, 95%CI 0.08-0.22, P<0.001) and OS (HR=0.24, 95%CI 0.15-0.41, P<0.001) . Landmark analysis was performed on 121 patients, of 85 patients achieving MRD negativity after the first cycle of consolidation, multivariate analyses showed that MRD negativity after the third cycle of consolidation was significantly-associated with longer DFS (HR=0.18, 95%CI 0.05-0.64, P=0.008) and OS (HR=0.14, 95%CI 0.04-0.50, P=0.003) . For the patients achieving MRD negativity after both the first and the third cycles of consolidation, the 3-year DFS rate in the allo-HSCT cohort had a higher trend compared with that in the chemotherapy cohort (75.2% vs 51.3%, P=0.082) , however, the 3-year OS rates in the 2 cohorts were similar (72.7% vs 68.7%, P=0.992) . In those with MRD positivity after the first and/or the third cycle of consolidation, 3-year DFS (64.8% vs 33.3%, P=0.006) and OS (77.0% vs 33.3%, P=0.028) rates in the allo-HSCT cohort were significantly higher than those in the chemotherapy cohort, and similar to those in the cohort achieving MRD negativity after both the first and the third cycles of consolidation and receiving allo-HSCT. Conclusions: MRD negativity after the first cycle of consolidation was a predictor for better outcome in adults with Ph(-) ALL in high-risk. The survival advantage of the allo-HSCT cohort was not pronounced compared with that in the chemotherapy cohort even in those with high-risk features but achieving MDR negativity after both the first and third cycles of consolidation. However, allo-HSCT could be a good option for the patients with MRD positivity after the first and/or the third cycle of consolidation.

Intestinal Microbiota Can Predict Acute Graft-versus-Host Disease Following Allogeneic Hematopoietic Stem Cell Transplantation

The intestinal microbiome plays an important role in the development of acute graft-versus-host disease (aGVHD). However, whether intestinal microbiota can predict the development of aGVHD has been reported only rarely. Here we conducted a prospective study of microbiota in 141 patients after allogeneic hematopoietic stem cell transplantation. We found lower microbiota diversity in the aGVHD group compared with the non-aGVHD group at day 0 and day 15 ± 1 (P = .018 and .009, respectively). Diversity was negatively associated with conditioning intensity (P = .017, day 0; P = .045, day 15) and β-lactam antibiotic administration (P = .004, day 15). Intensified conditioning and β-lactam antibiotics were associated with a lower regulatory T (Treg)/T helper 17 (Th17) cell ratio at day 15 (P = .030 and .047, respectively). At day 15, the levels of the inflammatory factors (tumor necrosis factor α, interleukin [IL]-6, IL-17A, IL-1β, and lipopolysaccharide) were higher in the intensified conditioning group compared with the standard group (P < .05). The accumulated intestinal microbiota (AIM) score was defined as microbiota diversity and gradient of the 4 bacterials (Lachnospiraceae, Peptostreptococcaceae, Erysipelotrichaceae, and Enterobacteriaceae) at day 15 post-transplantation. The AIM score was positively correlated with aGVHD grade (r = .481, P < .001), and the AIM score could be predictive of the development of aGVHD (grade II-IV aGVHD: area under the curve [AUC], .75, P < .001; grade III-IV aGVHD: AUC, .84, P < .001). These findings suggest that intestinal microbiota and conditioning might induce aGVHD by inflammatory factors and the Treg/Th17 balance. The constitution of the intestinal microbiota at neutrophil engraftment may predict the development of aGVHD.

Identification of TCR Vβ11-2-Dβ1-Jβ1-1 T cell clone specific for WT1 peptides using high-throughput TCRβ gene sequencing

We previously identified a TCR Vβ21 T cell clone which was specific to CML patients, and demonstrated that TCR Vα13/β21 gene-modified CD3+ T cells had specific cytotoxicity for HLA-A11+ K562 cells. However, it remains unclear which antigen is specifically recognized by the TCR Vβ21 T cell clone. In this study, CD3+ T cells from healthy donor peripheral blood were stimulated with the WT1 peptide or mixed BCR-ABL peptides in the presence or absence of IL-2 and IL-7. The distribution of the TCR Vβ repertoire was analyzed after different stimulations. We found that the mixed BCR-ABL peptides induced clonally expanded Vβ7-9-Dβ2-Jβ2-7 T cells while the Wilms Tumor 1 peptide induced clonally expanded Vβ11-2-Dβ1-Jβ1-1 T cells by high-throughput TCRβ sequencing and GeneScan. Interestingly, the sequence and CDR3 motif of Vβ11-2 T cell clone are similar to the TCR Vβ21 (a different TCR V region naming system) T cell clone that we previously found in CML patients. Thus, our findings suggest that the TCR Vβ21 T cell clone found in CML patients might be a T cell clone that specifically recognizes WT1.

Prophylactic oral NAC reduced poor hematopoietic reconstitution by improving endothelial cells after haploidentical transplantation

Poor graft function (PGF) and prolonged isolated thrombocytopenia (PT) remain life-threatening complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Endothelial cells (ECs) play a crucial role in regulating hematopoiesis in the bone marrow (BM) microenvironment. However, whether the impaired BM ECs are responsible for defective hematopoiesis in PGF and PT patients requires clarification, and clinical management is challenging. Two prospective clinical trials were included in the current study. In the first trial (N = 68), PGF and PT patients demonstrated defective BM ECs pre-HSCT and impaired BM EC dynamic reconstitution at early time points post-HSCT, which was positively correlated with reactive oxygen species (ROS) levels. Receiver operating characteristic curves showed that BM EC < 0.1% pre-HSCT could identify high-risk patients with PGF and PT. The second trial enrolled patients (N = 35) with EC < 0.1% who accepted oral N-acetyl-l-cysteine (NAC; 400 mg 3 times per day) from -14 days pre-HSCT to +2 months post-HSCT continuously, whereas the remaining EC ≥ 0.1% patients (N = 39) received allo-HSCT only. Prophylactic NAC intervention was safe and effective in preventing the occurrence of PGF and PT in EC < 0.1% patients by promoting the dynamic reconstitution of BM ECs and CD34+ cells, along with reducing their ROS levels, which was further confirmed by in situ BM trephine biopsy analyses. These findings suggest that the impaired BM ECs pre-HSCT are responsible for the defective hematopoiesis in PGF and PT patients. Therefore, improvement of BM ECs through prophylactic NAC intervention may be a promising therapeutic approach to promote hematopoietic reconstitution post-HSCT. This trial was registered at www.clinicaltrials.gov as #NCT03236220 and #NCT02978274.

Sorafenib Therapy Is Associated with Improved Outcomes for FMS-like Tyrosine Kinase 3 Internal Tandem Duplication Acute Myeloid Leukemia Relapsing after Allogeneic Hematopoietic Stem Cell Transplantation

The optimal therapy for patients with acute myeloid leukemia (AML) with FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) who relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains unclear. In this study we retrospectively evaluated the efficacy of sorafenib combined with other therapeutic strategies as salvage therapy for these patients. Eighty-three AML patients with FLT3-ITD relapsing after allo-HSCT were enrolled in this study. Fifty-three patients received salvage therapy containing sorafenib and 30 patients did not. Salvage therapy containing sorafenib was superior to that without sorafenib with respect to complete remission rates, overall survival (OS), and progression-free survival (PFS) (66.0% versus 30.0%, 46.8% versus 20.0%, and 44.9% versus 16.7%, respectively; P = .002, P = .003, and P = .001). Further subgroup analysis revealed that the OS and PFS of patients who received sorafenib combined with chemotherapy followed by donor lymphocyte infusion (DLI) were superior to those receiving other therapeutic regimens, including sorafenib combined with chemotherapy, chemotherapy followed by DLI, and monochemotherapy (P = .003, P < .001). Multivariate analysis revealed that salvage therapy including sorafenib was the only protective factor for longer OS (P = .035; hazard ratio [HR], .526); salvage therapy including sorafenib and DLI were the protective factors for longer PFS (P = .011, HR, .423; P = .019, HR, .508). Our data suggest that sorafenib therapy is associated with improved outcomes for FLT3-ITD AML relapsing after allo-HSCT, and whether sorafenib combined with chemotherapy followed by DLI reveals an optimal efficacy merits further study.

Association of Persistent Minimal Residual Disease with Poor Outcomes of Patients with Acute Myeloid Leukemia Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Background:

Several studies have shown that detection of minimal residual disease (MRD) in acute myeloid leukemia (AML) is an independent prognostic factor. This study aimed to evaluate the significance of dynamic MRD pretransplantation on outcome of AML patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Methods:

We retrospectively analyzed 145 consecutive AML patients undergoing allo-HSCT in complete remission status between June 2013 and June 2016. MRD was determined with multiparameter flow cytometry after the first and second courses of chemotherapy and pre-HSCT.

Results:

In matched sibling donor transplantation (MSDT) settings, patients with positive MRD had higher cumulative incidence of relapse (CIR) than those without MRD after the first (32.3 ± 9.7% vs. 7.7 ± 3.1%, χ² = 3.661, P = 0.055) or second course of chemotherapy (57.1 ± 3.6% vs. 12.5 ± 2.7%, χ² = 8.759, P = 0.003) or pre-HSCT (50.0 ± 9.7% vs. 23.0 ± 3.2%, χ² = 5.547, P = 0.019). In haploidentical SCT (haplo-SCT) settings, the MRD status at those timepoints had no significant impact on clinical outcomes. However, patients with persistent positive MRD from chemotherapy to pre-HSCT had higher CIR than those without persistent positive MRD both in MSDT and haplo-SCT settings. Patients with persistent positive MRD underwent MSDT had the highest relapse incidence, followed by those with persistent positive MRD underwent haplo-SCT, those without persistent MRD underwent haplo-SCT, and those without persistent MRD underwent MSDT (66.7 ± 9.2% vs. 38.5 ± 6.0% vs. 18.8 ± 8.7% vs. 12.0 ± 1.0%, χ² = 20.763, P < 0.001). Multivariate analysis showed that persistent positive MRD before transplantation was associated with higher CIR (hazard ratio [HR] = 1.69, 95% confidence interval [CI]: 1.200–2.382, P = 0.003), worse leukemia-free survival (HR = 1.812, 95% CI: 1.168–2.812, P = 0.008), and overall survival (HR = 2.354, 95% CI: 1.528–3.627, P < 0.001).

Conclusion:

Our results suggest that persistent positive MRD before transplantation, rather than positive MRD at single timepoint, could predict poor outcome both in MSDT and haplo-SCT settings.

Positive stool culture could predict the clinical outcomes of haploidentical hematopoietic stem cell transplantation

We aimed to identify the effect of positive stool cultures (PSCs) on the clinical outcomes of patients undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT) (n = 332). PSCs were observed in 61 patients (PSC group, 18.4%). Enterobacteriaceae in stool specimens was associated with a higher risk of bloodstream infection, and Candida in stool specimens was related to a higher risk of platelet engraftment failure. The cumulative incidence of infection-related mortality 1 year after haplo-HSCT in the PSC group was higher than that of the patients who showed persistently negative stool cultures (NSC group; 19.2% vs. 8.9%, P = 0.017). The probabilities of overall survival (71.4% vs. 83.8%, P = 0.031) and disease-free survival (69.6% vs. 81.0%, P = 0.048) 1 year after haplo-HSCT for the PSC group were significantly lower than those for the NSC group, particularly for patients who had Candida in their stool specimens. In multivariate analysis, Candida in stool specimens significantly increased the risk of mortality and was associated with poorer survival. Our results showed that PSC influenced the clinical outcomes after haplo-HSCT, particularly those who had Candida in their stool specimens.

Incidence and predictors of severe cardiotoxicity in patients with severe aplastic anaemia after haploidentical haematopoietic stem cell transplantation

The aim of this study was to evaluate the frequency of severe cardiac complications and to assess the ability of various factors to predict these complications in severe aplastic anaemia (SAA) patients after haploidentical transplantation. A retrospective study was conducted in 216 consecutive SAA patients who underwent haploidentical transplantation from 2006 to 2017. All patients received a unified regimen including busulfan, cyclophosphamide (CTX) and antithymocyte globulin at a single centre. A total of 12 (5.6%) patients developed grade III or IV cardiac toxicity. Patients with cardiotoxicity had significantly poorer overall survival (OS) than did those without cardiotoxicity (12.5 vs. 89.6%, P < 0.001). A multivariable model identified four independent adverse predictors of severe cardiotoxicity: pre-transplant ECOG score ( ≥ 2), abnormal ST-T wave on 12-lead ECG, hyperlipaemia and recalculated CTX dose ( ≥ 1.8 g/m²/d). The incidences of severe cardiotoxicity were 50.0%, 6.0% and 1.3% in the high- (3-4 factors), intermediate- (2 factors) and low-risk (0-1 factor) groups, respectively (P < 0.001). The corresponding OS rates were 49.0%, 80.4% and 90.3%, respectively (P < 0.001), at final follow-up. Therefore, patients with high-risk scores had the poorest outcomes and should be monitored closely. Reduced intensity conditioning might be recommended for these patients.