Haploidentical stem cell transplantation

Risk factors and outcomes of diffuse alveolar haemorrhage after allogeneic haematopoietic stem cell transplantation

Diffuse alveolar haemorrhage (DAH) is a life-threatening pulmonary complication occurring after allogeneic haematopoietic stem cell transplantation (allo-HSCT) without an explicit aetiology or a standard treatment. This study aimed to explore the occurrence and prognosis of DAH after allo-HSCT, in addition to comparing discrepancies in the incidence, clinical characteristics and outcomes of DAH between patients undergoing haploidentical HSCT (HID-HSCT) and matched related donor HSCT (MRD-HSCT). We retrospectively evaluated 92 consecutive patients among 3987 patients with a confirmed diagnosis of DAH following allo-HSCT (HID: 71 patients, MRD: 21 patients). The incidence of DAH after allo-HSCT was 2.3%, 2.4% after HID-HSCT and 2.0% after MRD-HSCT (P = 0.501). The prognosis of patients with DAH after transplantation is extremely poor. The duration of DAH was 7.5 days (range, 1-48 days). The probabilities of overall survival (OS) were significantly different between patients with and without DAH within 2 years after transplantation (P < 0.001). According to the Cox regression analysis, a significant independent risk factor for the occurrence of DAH was delayed platelet engraftment (P < 0.001), and a high D-dimer level (>500 ng/ml) was a significant risk factor for the poor prognosis of DAH. HID-HSCT is similar to MRD-HSCT in terms of the outcomes of DAH.

Comparison of hemorrhagic and ischemic stroke after allogeneic hematopoietic stem cell transplantation

Stroke is an important complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Nevertheless, few studies have been published to analyzed the occurrence and prognosis of stroke after allo-HSCT. From January 2007 to December 2018 in Peking University People's Hospital, 6449 patients received HSCT and there were 2.3% of patients diagnosed with stroke after allo-HSCT (hemorrhagic: 1.0%, ischemic: 1.3%). The median time to hemorrhagic and ischemic stroke after HSCT was 161 days and 137 days, respectively. In total, 8.4% of patients experienced neurological sequelae. The outcome was much worse in patients with stroke than in control subjects. The comparison of prognosis showed no statistical differences between patients with hemorrhagic stroke and those with ischemic stroke. Significant risk factors for hemorrhagic stroke were pretransplant central nervous system leukemia (CNSL), and delayed platelet engraftment. Risk factors associated with the occurrence of ischemic stroke included high-risk disease, prior venous thromboembolism (VTE), grade III-IV acute graft-versus-host disease (aGVHD), and thrombotic microangiopathy (TMA). Haplo-identical transplantation was not a risk factor for stroke and had no impact on the prognosis compared with HLA-matched HSCT. Altogether, these results show that stroke is a severe complication after allo-HSCT. The prognosis of posttransplant stroke did not differ between hemorrhagic and ischemic stroke.

Haploidentical peripheral blood stem cell transplantation with posttransplant cyclophosphamide in children and adolescents with hematological malignancies

BACKGROUND

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) using posttransplant cyclophosphamide (Cy) for graft versus host disease (GVHD) prophylaxis has emerged as an alternative transplant strategy for patients without related donors, especially in the setting of limited resources in which T-cell ex vivo depletion is not affordable. Experience with this transplant modality in children and adolescents is limited.

PROCEDURE

We report a retrospective analysis of 25 consecutive outpatients under 21 years of age with high-risk hematological malignancies, who received a haplo-HSCT using posttransplant Cy as GVHD prophylaxis.

RESULTS

Twenty-three (92%) of the 25 patients engrafted, and 20 (95%) of 21 evaluable subjects achieved full donor chimerism by day +30. One-year estimated overall survival and event-free survival were 50% and 33%, respectively. The cumulative incidence rate of severe acute GVHD was 19%, and 15% of patients developed chronic GVHD.

CONCLUSIONS

Haplo-HSCT with posttransplant Cy is a feasible therapeutic option for children and adolescents with high-risk hematological malignancies in a limited resource setting.

Infusion of basic fibroblast growth factor ameliorates acute graft versus host disease in mice after haploidentical hematopoietic stem cell transplantation

The aim of this study was to investigate the effect of basic fibroblast growth factor (bFGF) on acute graft versus host disease (aGVHD) in mice after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Haplo-HSCT mice model was established followed by dividing into three groups with 12 mice in each group, group 1 with infusion of 100g/kg bFGF, group 2 with infusion of 20 g/kg bFGF and control group without infusion. Clinical manifestation and survival time of mice after haplo-HSCT were monitored. On day 14 post transplantation, mice were sacrificed for pathology analysis of liver and the changes of mesenchymal stem cells (MSC). Compared to haplo-HSCT group, clinical manifestations of aGVHD in bFGF infusion group were significantly ameliorated. Furthermore, bFGF infusion also significantly prolonged the survival time of mice after transplantation (P<0.05) as demonstrated by Kaplan-Meier survival analysis with more infusion of bFGF, the longer survival of mice. Pathology analysis showed the severity of aGVHD in bFGF infusion group (1 and 2) was less severe than haplo-HSCT group with higher proliferation of bone marrow MSC in group 1. In conclusion, these studies demonstrated that infusion of bFGF ameliorated aGVHD in mice after haplo-HSCT.