Continuous and differential improvement in worldwide access to hematopoietic cell transplantation: activity has doubled in a decade with a notable increase in unrelated and non-identical related donors.

Promoting access to and excellence in hematopoietic cell transplantation (HCT) by collecting and disseminating data on global HCT activities is one of the principal activities of the Worldwide Network for Blood and Marrow Transplantation, a non-Governmental organization in working relations with the World Health Organization. HCT activities are recorded annually by member societies, national registries and individual centers including indication, donor type (allogeneic/autologous), donor match and stem cell source (bone marrow/peripheral blood stem cells/cord blood). In 2018, 1,768 HCT teams in 89 countries (six WHO regions) reported 93,105 (48,680 autologous and 44,425 allogeneic) HCT. Major indications were plasma cell disorders and lymphoma for autologous, and acute leukemias and MDS/MPN for allogeneic HCT. HCT number increased from 48,709 in 2007. Notable increases were seen for autoimmune diseases in autologous and hemoglobinopathies in allogeneic HCT. The number of allogeneic HCT more than doubled with significant changes in donor match. While HCT from HLA identical siblings has seen only limited growth, HCT from non-identical related donors showed significant increase worldwide. Strongest correlation between economic growth indicator of gross national income/capita and HCT activity/ten million population was observed for autologous HCT (r=0.79). HCT from unrelated donors showed strong correlation (r=0.68), but only moderate correlation (r=0.51) was detected from related donors. The use of HCT doubled in about a decade worldwide at different speed and with significant changes regarding donor match as a sign of improved access to HCT worldwide. Although narrowing, significant gaps remain between developing and non-developing countries.

CAR-T Therapy Followed by Hematopoietic Stem Cell Transplantation Can Improve Survival in Children Relapsed/Refractory Philadelphia Chromosome-positive B-cell Acute Lymphoblastic Leukemia.

BACKGROUND: Philadelphia chromosome (Ph)-positive B-cell acute lymphoblastic leukemia (ALL) has a high complete remission (CR) rate, but relapse and prolonged measurable residual disease remain serious problems. We sought to describe the CR rate measurable residual disease negative rate and address the results and safety of pediatric patients who underwent after receiving chimeric antigen receptor (CAR) specific for CD19 (CAR-19) followed by hematopoietic stem cell transplantation (HSCT) for the treatment of Ph-positive ALL. METHODS: A descriptive study was conducted at Peking University People's Hospital from September 2013 to January 2021. 13 patients with relapsed/refractory Ph-positive B-ALL who received CAR-T therapy followed by allo-HSCT were included. We concentrated on the overall patient survival and CR rate. RESULTS: The median time between CAR-T therapy and allo-HSCT was 58 days. Among all the patients, the CR rate was 100%, the flow cytometry negativity rate was 84.62%, and the BCR-ABL negativity rate was 53.85% at 1 month after CAR-T infusion. All the patients achieved a major molecular response in 6 months after HSCT. After a median follow-up of 45 months, the 3-year OS rate was 66.7%, and the 3-year DFS rate was 61.5%. The 3-year OS rate of patients with BCR-ABL-positive pre-HSCT was significantly lower than that in the BCR-ABL-negative group (40.0% vs. 85.7%, P=0.042). Also, the same trend was observed for the 3-year DFS rate but did not differ significantly (40.0% vs. 75.0%, P=0.233). CONCLUSIONS: CAR-T therapy followed by allo-HSCT can be a safe and effective treatment for Ph-positive B-ALL pediatric patients.

Salvage haploidentical transplantation for graft failure after first haploidentical allogeneic stem cell transplantation: an updated experience.

Graft failure is a fatal complication following allogeneic stem cell transplantation where a second transplantation is usually required for salvage. However, there are no recommended regimens for second transplantations for graft failure, especially in the haploidentical transplant setting. We recently reported encouraging outcomes using a novel method (haploidentical transplantation from a different donor after conditioning with fludarabine and cyclophosphamide). Herein, we report updated outcomes in 30 patients using this method. The median time of the second transplantation was 96.5 (33-215) days after the first transplantation. Except for one patient who died at +19d and before engraftment, neutrophil engraftments were achieved in all patients at 11 (8-24) days, while platelet engraftments were achieved in 22 (75.8%) patients at 17.5 (9-140) days. The 1-year OS and DFS were 60% and 53.3%, and CIR and TRM was 6.7% and 33.3%, respectively. Compared with the historical group, neutrophil engraftment (100% versus 58.5%, p < 0.001) and platelet engraftment (75.8% versus 32.3%, p < 0.001) were better in the novel regimen group, and OS was also improved (60.0% versus 26.4%, p = 0.011). In conclusion, salvage haploidentical transplantation from a different donor using the novel regimen represents a promising option to rescue patients with graft failure after the first haploidentical transplantation.

Haploidentical hematopoietic stem cell transplantation with busulfan, cyclophosphamide, and fludarabine conditioning for X-linked adrenal cerebral leukodystrophy.

OBJECTIVE: We investigated the safety and efficacy of haploidentical stem cell transplantation (SCT) in pediatric patients with X-linked adrenoleukodystrophy (ALD). METHODS: A retrospective analysis of transplantation data from 29 cases of ALD, treated between December 2014 and April 2022, was conducted. Neurologic function scores (NFS) were assessed. The conditioning regimen was busulfan 9.6 mg/kg, cyclophosphamide 200 mg/kg, and fludarabine 90 mg/m2 (BFC). Graft-versus-host disease prophylaxis consisted of anti-human thymocyte globulin, cyclosporine A, mycophenolate mofetil, and short course of methotrexate. RESULTS: Among the 29 cases, 14 cases (NFS = 0) were asymptomatic, and 15 (NFS ≥ 1) were symptomatic. The median age at SCT was 8 years (range: 4-16 years); the median follow-up time was 1058 days (range: 398-3092 days); 28 cases were father donors and 1 case was a grandfather donor. Hematopoietic reconstitution was successful in all patients, and all of them achieved complete donor chimerism at the time of engraftment. The leading cause of death was still primary disease progression (n = 4). Survival free of major functional disabilities was 100% in asymptomatic patients versus 66.67% in the symptomatic group (p = .018). CONCLUSION: BFC regimen used in haploidentical SCT was administered safely without major transplant-related complications even in symptomatic patients, and neurological symptoms were stabilized after SCT.

Mini-dose methotrexate combined with methylprednisolone for the initial treatment of acute GVHD: a multicentre, randomized trial.

BACKGROUND: There is an urgent unmet need for effective initial treatment for acute graft-versus-host disease (aGVHD) adding to the standard first-line therapy with corticosteroids after allogeneic haematopoietic stem cell transplantation (allo-HSCT). METHODS: We performed a multicentre, open-label, randomized, phase 3 study. Eligible patients (aged 15 years or older, had received allo-HSCT for a haematological malignancy, developed aGVHD, and received no previous therapies for aGVHD) were randomly assigned (1:1) to receive either 5 mg/m2 MTX on Days 1, 3, or 8 and then combined with corticosteroids or corticosteroids alone weekly. RESULTS: The primary endpoint was the overall response rate (ORR) on Day 10. A total of 157 patients were randomly assigned to receive either MTX plus corticosteroids (n = 78; MTX group) or corticosteroids alone (n = 79; control group). The Day 10 ORR was 97% for the MTX group and 81% for the control group (p = .005). Among patients with mild aGVHD, the Day 10 ORR was 100% for the MTX group and 86% for the control group (p = .001). The 1-year estimated failure-free survival was 69% for the MTX group and 41% for the control group (p = .002). There were no differences in treatment-related adverse events between the two groups. CONCLUSIONS: In conclusion, mini-dose MTX combined with corticosteroids can significantly improve the ORR in patients with aGVHD and is well tolerated, although it did not achieve the prespecified 20% improvement with the addition of MTX. TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov (NCT04960644).

Outcomes and prognosis of haploidentical haematopoietic stem cell transplantation in children with FLT3-ITD mutated acute myeloid leukaemia.

The presence of internal tandem duplication mutations in the FMS-like tyrosine kinase 3 receptor (FLT3-ITD) is a poor prognostic predictor in paediatric patients with acute myeloid leukaemia (AML). We evaluated the treatment outcomes and prognostic factors of 45 paediatric patients with FLT3-ITD AML who achieved complete remission before haploidentical haematopoietic stem cell transplantation (haplo-HSCT) at our institution from 2012 to 2021. Among the 45 patients, the overall survival (OS), event­free survival (EFS), and cumulative incidence of relapse (CIR) rates were 74.9% ± 6.6%, 64.1% ± 7.2%, and 31.4% ± 7.1%, respectively, with 48.8 months of median follow-up. Univariate and multivariate analyses associated positive minimal residual disease (MRD) at pre-HSCT and non-remission (NR) after introduce 1 with inferior long-term survival. The 100-day cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was 35.6% ± 5.2%, and that of grade III-IV aGVHD was 15.6% ± 3.0% The overall 4-year cumulative incidence of chronic graft-versus-host disease after transplantation was 35.7% ± 9.8%, respectively. In conclusion, haplo-HSCT may be a feasible strategy for paediatric patients with FLT3-ITD AML, and pre-HSCT MRD status and NR after introduce 1 significantly affected the outcomes.

Hematologic health services and practical characteristics: report of a nationwide survey among Chinese hematologists.

BACKGROUND: In the past 40 years, China has experienced tremendous economic development, but the current situation of hematologists has rarely been reported. A landscape survey of human resources is essential for healthcare development and policy formulation in the future. METHODS: The Chinese Society of Hematology initiated a survey of Chinese hematologists in mainland China for evaluating demographic and practice characteristics. Respondents were anonymous, and there were no limitations regarding their age, sex, etc. RESULTS: Totally 2032 hematologists responded, with a median age bracket of 36-45 years. Respondents were well engaged into subspecialties, and 28.1% acquired doctorates of philosophy. Hematopoietic cell transplantation (HCT) centers have been established all over China. Higher-GDP regions reported more advantages, including bigger scale of transplant centers (P < 0.001), younger age structure (P = 0.039), better education qualifications (P = 0.001) and less turnover intentions (P = 0.004), despite of increased risk of medical disputes (P = 0.028). Although females accounted for 65.5% of hematologists, males were older (P < 0.001), and had more senior professional titles (P < 0.001), academic positions (P < 0.001), opportunities for continuing education (P < 0.001), and paper publishing in the recent two years (P = 0.001). For turnover intention, the higher GDP regions led to an independently reduced risk (HR = 0.673, 95%CI [0.482-0.940], P = 0.020), whereas medical disputes resulted in an increased the risk (HR = 2.037, 95%CI [1.513-2.743], P < 0.001). Considering the impact of the COVID-19 pandemic, majority of respondents believed that the decline in patient visits and delay in treatment was within 30%. 67.9% of respondents reported a decrease of the use of bone marrow as grafts but 18.8% reported an increase of cord blood units. 35.0% of the respondents switched their daily work to support the anti-epidemic medical activities. CONCLUSIONS: We concluded the discipline of hematology in China has flourished in recent years with a young workforce, while regional economic and gender disparities warrant further continuous optimization. Joint efforts against the impact of COVID-19 are needed in the post-pandemic era.

Mesenchymal stromal cells plus basiliximab improve the response of steroid-refractory acute graft-versus-host disease as a second-line therapy: a multicentre, randomized, controlled trial.

BACKGROUND: For patients with steroid-refractory acute graft-versus-host disease (SR-aGVHD), effective second-line regimens are urgently needed. Mesenchymal stromal cells (MSCs) have been used as salvage regimens for SR-aGVHD in the past. However, clinical trials and an overall understanding of the molecular mechanisms of MSCs combined with basiliximab for SR-aGVHD are limited, especially in haploidentical haemopoietic stem cell transplantation (HID HSCT). METHODS: The primary endpoint of this multicentre, randomized, controlled trial was the 4-week complete response (CR) rate of SR-aGVHD. A total of 130 patients with SR-aGVHD were assigned in a 1:1 randomization schedule to the MSC group (receiving basiliximab plus MSCs) or control group (receiving basiliximab alone) (NCT04738981). RESULTS: Most enrolled patients (96.2%) received HID HSCT. The 4-week CR rate of SR-aGVHD in the MSC group was obviously better than that in the control group (83.1% vs. 55.4%, P = 0.001). However, for the overall response rates at week 4, the two groups were comparable. More patients in the control group used ≥ 6 doses of basiliximab (4.6% vs. 20%, P = 0.008). We collected blood samples from 19 consecutive patients and evaluated MSC-derived immunosuppressive cytokines, including HO1, GAL1, GAL9, TNFIA6, PGE2, PDL1, TGF-ß and HGF. Compared to the levels before MSC infusion, the HO1 (P = 0.0072) and TGF-ß (P = 0.0243) levels increased significantly 1 day after MSC infusion. At 7 days after MSC infusion, the levels of HO1, GAL1, TNFIA6 and TGF-ß tended to increase; however, the differences were not statistically significant. Although the 52-week cumulative incidence of cGVHD in the MSC group was comparable to that in the control group, fewer patients in the MSC group developed cGVHD involving ≥3 organs (14.3% vs. 43.6%, P = 0.006). MSCs were well tolerated, no infusion-related adverse events (AEs) occurred and other AEs were also comparable between the two groups. However, patients with malignant haematological diseases in the MSC group had a higher 52-week disease-free survival rate than those in the control group (84.8% vs. 65.9%, P = 0.031). CONCLUSIONS: For SR-aGVHD after allo-HSCT, especially HID HSCT, the combination of MSCs and basiliximab as the second-line therapy led to significantly better 4-week CR rates than basiliximab alone. The addition of MSCs not only did not increase toxicity but also provided a survival benefit.

Clinical characteristics and prognosis of acute myeloid leukemia patients with Runt-related transcription factor 1 mutation: A single-center retrospective analysis.

This study aimed to investigate the clinical characteristics and prognosis of Runt-related transcription factor 1 (RUNX1) mutant acute myeloid leukemia (AML) patients by comparing the features of AML patients with or without RUNX1 mutation. We retrospectively analyzed 180 AML patients including 36 AML patients with mutant RUNX1(AML-RUNX1mut ) and 144 AML patients with wild-type RUNX1(AML-RUNX1wt ) were selected using the case-pair method(1:4). Compared to AML-RUNX1wt , AML-RUNX1mut showed higher frequency of ASXL1 (p < 0.001), SRSF2 (p < 0.001), BCORL1 (p < 0.001), RAS (p = 0.010) mutations, and absent NPM1 mutations (p = 0.022). The 3-year overall survival (OS) and disease-free survival (DFS) of AML-RUNX1mut and AML-RUNX1wt were 73.1% versus 68.0% (p = 0.64) and 80.7% versus 71.6% (p = 0.37), respectively. AML-RUNX1mut receiving allogeneic hematopoietic cell transplantation (allo-HSCT) showed better survival than those who did not receive allo-HSCT (3-year OS, 84.3% vs. 52.7%; p = 0.006). Multivariate analysis showed that EZH2 mutation (p = 0.003), white blood cell (WBC) ≥30 × 109 /L (p = 0.036) and age ≥60 years (p = 0.038) were significant independent risk factors for inferior OS of AML-RUNX1mut ; WBC ≥30 × 109 /L (p = 0.013) and DNMT3A mutation (p = 0.045) were significant independent risk factors for shorter DFS of AML-RUNX1mut . In conclusion, AML-RUNX1mut showed unique clinical characteristics, but the survival between AML-RUNX1mut and AML-RUNX1wt were comparable. EZH2 co-mutation, DNMT3A co-mutation, old age and high WBC count were associated with inferior survival of AML-RUNX1mut . Allo-HSCT can significantly improve the prognosis of AML-RUNX1mut .

A prognostic score system in adult T-cell acute lymphoblastic leukemia after hematopoietic stem cell transplantation.

Adult T-cell acute lymphoblastic leukemia (T-ALL) is highly aggressive with poor prognoses, while hematopoietic stem cell transplantation (HSCT) is a curable option. However, no transplant-specific prognostic model for adult T-ALL is available. We identified 301 adult T-ALL patients who received HSCT at our hospital between 2010 and 2022. These patients were randomly assigned at a 7:3 ratio to a derivation group of 210 patients and a validation group of 91 patients. Next, we developed a prognostic risk score system for adult T-ALL with HSCT, which we named COMM, including 4 predictors (central nervous system involvement, Non-CR1 (CR2+ or NR) at HSCT, minimal residual disease (MRD) ≥ 0.01% after first induction therapy, and MRD ≥ 0.01% before HSCT). Patients were categorized into three risk groups, low-risk (0), intermediate-risk (1-4), and high-risk (5-12), and their 3-year overall survival (OS) were 87.5% (95%CI, 78-93%), 65.7% (95%CI, 53-76%) and 20% (95%CI, 10-20%; P < 0.001), respectively. The area under the subject operating characteristic curve for 2-, 3- or 5-year OS in the derivation cohort and in the validation cohort were all greater than 0.75. Based on internal validation, COMM score system proved to be a reliable prognostic model that could discriminate and calibrate well. We expect that the first prognostic model in adults T-ALL after HSCT can provide a reference of prognostic consultation for patients and families, and also contribute to future research to develop risk adapted interventions for high-risk populations.

Outcome and prognostic factors of haploidentical allogeneic hematopoietic stem cell transplantation in pediatric relapsed or refractory ETV6/RUNX1-positive acute lymphoblastic leukemia.

INTRODUCTION: the role of haploidentical allogeneic hematopoietic stem cell transplantation (haplo-HSCT) in pediatric patients with relapsed or refractory (R/R) ETV6/RUNX1-positive acute lymphoblastic leukemia (ALL) is unclear. This study aimed to identify prognostic factors and explore the role of haplo-HSCT in the treatment of ETV6/RUNX1-positive ALL. METHODS: we analyzed the clinical characteristics and treatment outcomes of 20 pediatric patients who were diagnosed with ETV6/RUNX1-positive ALL and received chemotherapy/chimeric antigen receptor T-cell bridged to haplo-HSCT between 2016 and 2021 at our institution. RESULTS: with a median follow-up time of 47 months, the 3-year cumulative incidence of relapse, disease-free survival, and overall survival were 35.9% (95% confidence interval (CI): 15.3-57.1%), 59.1% (95% CI: 37.2-81.0%), and 75.0% (95% CI: 56.0-94.0%), respectively. Multivariate analysis revealed that pre-HSCT measurable residual disease (MRD) positivity (hazard ratio, 13.275; 95% CI: 2.406-73.243; P = 0.003) had a significant negative impact on relapse. A total of 7 patients experienced positive ETV6/RUNX1 gene expression at a median of 7.2 months after haplo-HSCT, 5 of them experienced relapse at a median time of 12.1 months after haplo-HSCT. ROC curve analysis was performed to analyze the significance of pre-HSCT and post-HSCT ETV6/RUNX1 transcripts for predicting relapse; the AUC were 0.798 (95% CI: 0.567-1.0, P=0.035) and 0.875 (95% CI: 0.690-1.0, P=0.008), respectively. The optimal cut-off points to predict an inevitable relapse were 0.011% and 0.0019%, respectively. CONCLUSION: patients with R/R ETV6/RUNX1-positive ALL may benefit from haplo-HSCT. Deeply eliminating pre-HSCT MRD and preemptive treatment for post-HSCT MRD may be crucial to further improving the prognosis.

Clinical risk factors and prognostic model for patients with bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation.

Bronchiolitis obliterans syndrome (BOS) is a common and potentially devastating noninfectious pulmonary complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Currently, predictive tools for BOS are not available. We aimed to identify the clinical risk factors and establish a prognostic model for BOS in patients who undergo allo-HSCT. We retrospectively identified a cohort comprising 195 BOS patients from 6100 consecutive patients who were allografted between 2008 and 2022. The entire cohort was divided into a derivation cohort and a validation cohort based on the time of transplantation. Via multivariable Cox regression methods, declining forced expiratory volume at 1 s (FEV1) to <40%, pneumonia, cGVHD except lung, and respiratory failure were found to be independent risk factors for the 3-year mortality of BOS. A risk score called FACT was constructed based on the regression coefficients. The FACT model had an AUC of 0.863 (95% CI: 0.797-0.928) in internal validation and 0.749 (95% CI: 0.621-0.876) in external validation. The calibration curves showed good agreement between the FACT-predicted probabilities and actual observations. The FACT risk score will help to identify patients at high risk and facilitate future research on developing novel, effective interventions to personalize treatment.

A predictive model of herpes zoster after allogeneic hematopoietic stem cell transplantation: VZV reactivation following antiviral prophylaxis discontinuation.

Herpes zoster (HZ) refers to the rash appearing on dermatomes due to varicella zoster virus (VZV) reactivation. The incidence of HZ is significantly higher in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients than in non-HSCT recipients. Although acyclovir prophylaxis is routinely administered to every allo-HSCT recipient for 1 year after transplantation, some individuals eventually develop late-onset HZ after completing prophylaxis. Little information is known about the clinical features of HZ after prophylactic antiviral treatment discontinuation, and an effective predictive model of late-onset HZ needs to be established. A total of 3366 patients who had received allo-HSCT from 2012 to 2017 were included in our study, among whom 201 developed HZ after 1 year (late-onset HZ). We designed a nested case-control study to identify potential predictors of late-onset HZ. Finally, we established a predictive model using binary logistic regression analysis. Age (p < .001), use of immunosuppressants at +1 year (p < .001), CD4-CD8 ratio at +1 year (p < .001), certain mental disorders (depression, anxiety, insomnia and adjustment disorder) (p < .001), engraftment time of neutrophils (p < .001), and CD8+ cell count at +30 days (p < .001) were independent predictors of late-onset HZ. A risk grading system was established based on regression coefficients. Discrimination and calibration analysis indicated that the model had good performance. We also identified several predictive factors of the incidence of HZ-related complications. This is the first scoring system for predicting the incidence of late-onset HZ after allo-HSCT. This model can be applied to identify individuals at high risk of late-onset HZ in the early period after receiving allo-HSCT.

Long-term follow-up of haploidentical haematopoietic stem cell transplantation in paediatric patients with high-risk acute myeloid leukaemia: Report from a single centre.

Data from 200 children with high-risk acute myeloid leukaemia who underwent their first haploidentical haematopoietic stem cell transplantation (haplo-HSCT) between 2015 and 2021 at our institution were analysed. The 4-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) were 71.9%, 62.3% and 32.4% respectively. The 100-day cumulative incidences of grade II-IV and III-IV acute graft-versus-host disease (aGVHD) were 41.1% and 9.5% respectively. The 4-year cumulative incidence of chronic GVHD (cGVHD) was 56.1%, and that of moderate-to-severe cGVHD was 27.3%. Minimal residual disease (MRD)-positive (MRD+) status pre-HSCT was significantly associated with lower survival and a higher risk of relapse. The 4-year OS, EFS and CIR differed significantly between patients with MRD+ pre-HSCT (n = 97; 63.4%, 51.4% and 41.0% respectively) and those with MRD-negative (MRD-) pre-HSCT (n = 103; 80.5%, 73.3% and 23.8% respectively). Multivariate analysis also revealed that acute megakaryoblastic leukaemia without Down syndrome (non-DS-AMKL) was associated with extremely poor outcomes (hazard ratios and 95% CIs for OS, EFS and CIR: 3.110 (1.430-6.763), 3.145 (1.628-6.074) and 3.250 (1.529-6.910) respectively; p-values were 0.004, 0.001 and 0.002 respectively). Thus, haplo-HSCT can be a therapy option for these patients, and MRD status pre-HSCT significantly affects the outcomes. As patients with non-DS-AMKL have extremely poor outcomes, even with haplo-HSCT, a combination of novel therapies is urgently needed.

Targeting TFH cells is a novel approach for donor-specific antibody desensitization of allograft candidates: an in vitro and in vivo study.

The presence of donor-specific antibodies (DSA) are associated with graft failure either following human leukocyte antigen (HLA)-mismatched allogeneic stem cell transplantation or after organ transplantation. Although targeting B cells and plasma cells have been used for desensitization, there have been reports of failure. T-follicular helper (Tfh) cells assist B cells in differentiating into antibody-secreting plasma cells. We used haploidentical allograft as a platform to investigate the possibility of targeting Tfh cells to desensitize DSA. The quantities of circulating Tfh (cTfh) cell subsets in allograft candidates were abnormal, and these cells, including the cTfh2 and cTfhem cell subsets, were positively related to the production of anti-HLA antibodies. Ex vivo experiments showed that the cTfh cells of anti-HLA antibody-positive allograft candidates could induce B cells to differentiate into DSA-producing plasmablasts. The immune synapse could be involved in the assistance of cTfh cells to B cells in antibody production. In vitro experiments and in vivo clinical pilot studies indicated that targeting cTfh cells with sirolimus can inhibit their auxiliary function in assisting B cells. Ex vivo and in vivo studies demonstrated the effect of sirolimus and rituximab on DSA desensitization compared with either sirolimus or rituximab alone (60%, 43.75%, and 30%, respectively). Our findings provide new insight into the role of Tfh cells in the pathogenesis of DSA production in HLA-mismatched transplant candidates. Our data also indicate that targeting Tfh cells is a novel strategy for DSA desensitization and combination of sirolimus and rituximab might be a potential therapy. The prospective cohort of this study is registered at http://www.chictr.org.cn as #ChiCTR-OPC-15006672.

The impact of donor-specific anti-HLA antibody levels on primary poor graft function and graft rejection in rituximab desensitized haploidentical stem cell transplantation.

This study investigates the influence of donor-specific anti-HLA antibodies (DSA) levels on primary poor graft function (PGF) and graft rejection (GR) after haploidentical stem cell transplantation (haplo-SCT) with rituximab desensitization. A total of 155 DSA-positive haplo-SCT candidates with mean fluorescence intensity (MFI) between 2000 and 10,000 were enrolled in this prospective clinical trial. Receiver operating characteristic (ROC) curves determined the optimal DSA MFI cutoff for identifying high-risk patients. Patients were categorized into two groups: DSA low-level group (2000 ≤ DSA MFI < 5000, Group A) and high-level group (5000 ≤ DSA MFI ≤ 10,000, Group B). The incidence of primary PGF was 6.5% (2.6%-10.3%), while GR incidence was 0.6% (0.0%-1.9%). Group A had significantly lower primary PGF rates than Group B (2.3% [0.0%-5.7%] vs. 12.9% [4.8%-21.0%], p = 0.017). Only one patient in Group B experienced GR. High DSA levels (5000 ≤ MFI ≤ 10,000) were identified as the sole independent risk factor for primary PGF and GR after haplo-SCT with rituximab desensitization (HR = 7.282, 95% CI 1.517-34.953, p = 0.013). The 4-year cumulative incidence of relapse, non-relapse mortality, disease-free survival, and overall survival were 14.7% (11.6%-17.8%), 16.3% (13.1%-19.4%), 69.0% (65.9%-76.2%), and 70.6% (66.4%-74.8%), respectively. DSA levels have an impact on efficiency of rituximab desensitization, and a DSA MFI threshold is provided for predicting primary PGF and GR.

Prognostic Factors and Outcomes in Patients With Septic Shock After Allogeneic Hematopoietic Stem Cell Transplantation.

Septic shock remains a potentially life-threatening complication among allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. There is a paucity of information on the clinical characteristics, outcome and prognostic factors of septic shock patients after allo-HSCT. We aimed to describe the clinical characteristics of septic shock after allo-HSCT and its associated health outcomes and to evaluate the role of patient demographics, transplantation-related laboratory and clinical variables associated with the short-term mortality of septic shock after allo-HSCT. We retrospectively studied 242 septic shock patients from 6105 consecutive patients allografted between 2007 and 2021. We assessed 29 risk factors as candidate predictors and used multivariable logistic regression to establish clinical model. The primary outcome was 28-day mortality. The median age of the subjects was 34 (IQR 24 to 45) years. A total of 148 patients (61.2%) had positive blood cultures. Gram-negative bacilli accounted for 61.5% of the positive isolates, gram-positive cocci accounted for 12.2%, and fungi accounted for 6.1%. Coinfections were found in 30 (20.3%) patients. Escherichia coli was the dominant isolated pathogen (31.1%), followed by Pseudomonas spp. (12.8%) and Klebsiella pneumoniae (10.1%). With a median follow-up of 34 (IQR: 2 to 528) days, a total of 142 (58.7%) patients died, of whom 118 (48.8%) died within the first 28 days after septic shock diagnosis, 131 (54.1%) died within 90 days, and 141 (58.3%) died within 1 year. A large majority of deaths (83.1% [118/142]) occurred within 28 days of septic shock diagnosis. Finally, 6 independent predictive variables of 28-day mortality were identified by multivariable logistic regression: time of septic shock, albumin, bilirubin, PaO2/FiO2, lactate, and sepsis-induced coagulopathy. Patients with late onset shock had higher 28-day mortality rates (64.6% versus 25.5%, P < .001) and more ICU admission (32.6% versus 7.1%, P < .001) than those with early onset shock. We highlight the poor survival outcomes in patients who develop septic shock, emphasizing the need for increasing awareness regarding septic shock after allo-HSCT. The information from the current study may help to assist clinicians in identifying high-risk patients.

Report on hematopoietic cell transplantations performed in 2018/2019 focusing on the trends of selection of stem cell sources in the Asia-Pacific region: APBMT Activity Survey.

The number of hematopoietic stem cell transplantations (HCTs) is increasing annually worldwide, and the Asia-Pacific (AP) region is no exception. We report on the absolute number of HCTs in 2018 and 2019 and the trends in graft selection and disease indication in the past few decades. In 2018, 24,292 HCTs were performed in the AP region, of which 8,754 (36.0%) were autologous and 15,538 (64.0%) were allogeneic. Among the allogeneic HCTs, 10,552 (67.9%) of the recipients were related to their donors, whereas 4,986 (32.1%) were unrelated. In 2019, 27,583 HCTs were reported, of which 17,613 (63.9%) were allogeneic and 9,970 (36.1%) were autologous. Although, in 2010, there was a nearly equal number of related and unrelated HCTs, the difference has shown an annual increase, with more than double (2.05) the number of related than unrelated HCTs in 2019. Recent trends in the AP region show that peripheral blood has overwhelmingly surpassed the bone marrow as a graft source for both related and unrelated HCTs, with the haploidentical donor type being preferred; however, their trends in each country/region were quite different among countries/regions. In 2019, the main conditions requiring HCT were acute myelogenous leukemia (n=6,629 [24.0%]), plasma cell disorders (PCD) (n=4,935 [17.9%]), malignant lymphoma (ML) (n=4,106 [14.9%]), acute lymphoblastic leukemia (AML) (n=3,777 [13.7%]), myelodysplastic syndrome or myelodysplastic/myeloproliferative neoplasm (n=1,913 [6.9%]), severe aplastic anemia (n=1,671 [6.1%]), and hemoglobinopathy (n=910 [3.3%]). PCD and ML were the main indications for autologous HCT, and the number of PCD cases has grown more prominent than the corresponding of ML. The increased number of allogeneic transplants for hemoglobinopathy remains prominent, as well as that of AML and acute lymphocytic leukemia for the past 5 years. There was a significant regional variation in the number of facilities performing HCTs, ranging from one in Mongolia and Nepal to 313 in Japan, and differing regional densities varying from 0.1 in Indonesia and Pakistan to 24.7 in Japan. The total transplant density per 10 million population in each country/region also differed (0.2 in Indonesia and 627 in New Zealand). This annual Activity Survey aims to help all participating countries/regions understand the changes in HCT, serve as an asset in promoting HCT activities in the AP region, and be used as a reference for comparison with other registries from Europe and the United States.