Low-dose unfractionated heparin prophylaxis is a safe strategy for the prevention of hepatic sinusoidal obstruction syndrome after myeloablative adult allogenic stem cell transplant

Effect and safety of recombinant human thrombopoietin on haematopoietic reconstitution after allogeneic haematopoietic cell transplantation

Delayed platelet engraftment (DPE) and thrombocytopenia are common complications following myeloablative conditioning in the advanced stage of allogeneic haematopoietic cell transplantation (allo-HCT), and they are associated with transplantation-related mortality and poor prognosis. Therefore, promoting haematopoietic reconstitution after allo-HCT plays a key role in improving patient outcomes. The aim of this retrospective study was to assess the effectiveness and safety of recombinant human thrombopoietin (rhTPO) in promoting haematopoietic reconstruction after allo-HCT. The study included 210 patients who underwent transplantation, with 158 in the rhTPO group and 52 in the control group. Of the total patient population, 120 were males and 90 were females, with a median age of 31 years (range=6 to 59 years). The results showed that the rhTPO group had a median platelet engraftment time that was 14.1 days shorter than that of the control group (14.1 days vs. 21.9 days; P < 0.001). The time for platelet count recovery to 50 × 10^9/L was also shorter in the rhTPO group than in the control group (21.7 days vs. 30.3 days; P < 0.001). Additionally, the granulocyte engraftment time was shorter in the rhTPO group (14.3 days vs. 18.2 days; P < 0.001). There was no significant difference in overall survival (OS) between the rhTPO group and the control group at 2 years after transplantation (77.2% vs. 65.4 %; P = 0.08). Furthermore, there were no significant differences in the amount of platelet transfusions, the rate of platelet engraftment, the rate of DPE, or the incidence of Grade 4 haemorrhage between the groups. Moreover, no adverse reactions were found in the rhTPO group. This study demonstrated that rhTPO administration after allo-HCT effectively reduced the time required for platelet and granulocyte engraftment and was safe.

Risk Factors for Sinusoidal Obstruction Syndrome After Hematopoietic Stem Cell Transplantation in Children and Young Adults: A Systematic Review and Meta-Analysis

OBJECTIVE AND BACKGROUND

Sinusoidal obstruction syndrome (SOS) is a life-threatening complication in hematopoietic stem cell transplantation (HSCT) patients. However, the related risk factors in pediatric and young adult HSCT recipients remain unclear. Thus, we conducted this meta-analysis to identify potential risk factors for SOS in children and young adults undergoing HSCT.

METHOD

We acquired related articles through searching PubMed, EMBASE, and the Cochrane Library up to May 31, 2024. We calculated odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to identify potential risk factors.

RESULTS

A total of 12 studies with 7644 HSCT recipients were included. Bone marrow transplantation (OR = 1.35, 95% CI: 1.03-1.77, I2 = 0%), busulfan (BU) (OR = 3.63, 95% CI: 1.78-7.38, I2 = 70%), and fludarabine (FLU) (OR = 1.55, 95% CI: 1.09-2.21, I2 = 16%) were risk factors for SOS after HSCT in children and young adults.

CONCLUSION

Bone marrow transplantation and the use of BU or FLU might be risk factors for SOS after HSCT in children and young adults.

The evolving role of liver sinusoidal endothelial cells in liver health and disease

LSECs are a unique population of endothelial cells within the liver and are recognized as key regulators of liver homeostasis. LSECs also play a key role in liver disease, as dysregulation of their quiescent phenotype promotes pathological processes within the liver including inflammation, microvascular thrombosis, fibrosis, and portal hypertension. Recent technical advances in single-cell analysis have characterized distinct subpopulations of the LSECs themselves with a high resolution and defined their gene expression profile and phenotype, broadening our understanding of their mechanistic role in liver biology. This article will review 4 broad advances in our understanding of LSEC biology in general: (1) LSEC heterogeneity, (2) LSEC aging and senescence, (3) LSEC role in liver regeneration, and (4) LSEC role in liver inflammation and will then review the role of LSECs in various liver pathologies including fibrosis, DILI, alcohol-associated liver disease, NASH, viral hepatitis, liver transplant rejection, and ischemia reperfusion injury. The review will conclude with a discussion of gaps in knowledge and areas for future research.

Early vascular endothelial complications after hematopoietic cell transplantation: Role of the endotheliopathy in biomarkers and target therapies development

This work aims to review the role of endothelial dysfunction underlying the main complications appearing early after autologous and allogeneic hematopoietic cell transplantation (HCT). The endothelial damage as the pathophysiological substrate of sinusoidal obstruction syndrome (SOS) is well established. However, there is growing evidence of the involvement of endothelial dysfunction in other complications, such as acute graft-versus-host disease (aGVHD) and transplant-associated thrombotic microangiopathy (TA-TMAs). Moreover, HCT-related endotheliopathy is not only limited to the HCT setting, as there is increasing evidence of its implication in complications derived from other cellular therapies. We also review the incidence and the risk factors of the main HCT complications and the biological evidence of the endothelial involvement and other linked pathways in their development. In addition, we cover the state of the art regarding the potential use of the biomarkers of endotheliopathy in the prediction, the early diagnosis, and the follow-up of the HCT complications and summarize current knowledge points to the endothelium and the other linked pathways described as potential targets for the prevention and treatment of HCT-complications. Lastly, the endothelium-focused therapeutic strategies that are emerging and might have a potential impact on the survival and quality of life of post-HCT-patients are additionally reviewed.