British Journal of Haematology最新文献

Iron is required for key physiological processes, like oxygen transport, energy production and cell proliferation. Body iron homeostasis is regulated by the erythroferrone-hepcidin-ferroportin (FPN) axis, which mainly acts on absorptive duodenal cells and macrophages involved in iron recycling from red blood cell breakdown. In addition to systemic iron regulation, macrophages are also involved in local iron release to neighbouring cells. Similarly, bone marrow (BM)-resident macrophages could represent promptly available local sources of iron for developing haematopoietic cells. To study the impact of macrophage-released iron on BM haematopoietic stem and progenitor cells, we employed mice with targeted deletion of Fpn in the myeloid lineage (Fpn conditional knockout or Fpn-cKO). Fpn-cKO mice develop age-related anaemia and microcytaemia, reduction of BM erythroblasts and preferential megakaryopoiesis at the expenses of erythropoiesis, suggesting that red cells are mostly affected by the lack of myeloid-derived iron delivery. Transferrin receptor 1 surface expression is higher in Fpn-cKO mice than littermate controls in all the BM subpopulation analysed, starting from haematopoietic stem cells, indicating a broad BM sensitivity to lower iron availability. Last, Fpn-cKO mice activate systemic compensatory mechanisms, such as extramedullary haematopoiesis and erythroferrone upregulation, albeit not sufficient to overcome anaemia.

Erythropoiesis, the process of red blood cell (RBC) development from haematopoietic stem cells, is crucial in haematology research due to its intricate regulation and implications in various pathologies such as anaemia and haemoglobinopathies. Humanized mice, created by introducing human cells or tissues into immunodeficient mice, offer a promising avenue in vivo approach. However, challenges persist in fully replicating human erythropoiesis in these models, particularly in generating mature human RBCs capable of sustained circulation. This review discusses the differences between human and mouse erythropoiesis, recent progress made using refined humanized mouse models for studying human erythropoiesis and erythropoietic disorders, the challenges that impede a faithful mimicking of human phenotypes in these mice and recommendations for future research improvements. Despite progress being made, enhancing the translational potential of humanized mouse models for human erythropoiesis research remains a priority.

The outcomes are poor for paediatric patients with T-cell acute lymphoblastic leukaemia (T-ALL) who relapse after haematopoietic stem cell transplantation (HSCT). However, studies focusing on paediatric patients with T-ALL following haploidentical HSCT (haplo-HSCT) are limited. We retrospectively identified a consecutive cohort comprising of 128 paediatric T-ALL after haplo-HSCT from 2642 consecutive ALL patients between January 2010 and June 2022. The 2-year overall survival and leukaemia-free survival were 67.77% ± 4.21% and 66.34% ± 3.82%, respectively, and the cumulative incidence of relapse (CIR) and non-relapse mortality were 33.82% ± 0.70% and 12.65% ± 0.46% respectively. According to the multivariate Cox regression analysis, CD34 cells, minimal residual disease (MRD) ≥0.01% before HSCT, chronic graft-versus-host disease (cGvHD) and cytomegalovirus were associated with relapse (p < 0.05). To develop a scoring system for stratifying patients, we combined the variables and stratified them into low (0-2 points) and high (3, 4) groups. Consequently, the 2-year CIR in low and high groups were 23.76% ± 1.83% and 48.22% ± 2.42% (p = 0.009), respectively. Children with T-ALL have poor long-term survival, and haplo-HSCT is a potent and safe treatment; however, the incidence of relapse is high. Eliminating pre-HSCT MRD, guaranteeing sufficient CD34 cells infusion and the occurrence of cGvHD and cytomegalovirus reactivation may benefit from relapse.

We sought to identify new candidate drugs for repurposing to myelodysplastic syndromes (MDS). Connectivity map analysis was performed on gene expression signatures generated from bone marrow CD34⁺ cells of splicing factor mutant MDS patients. Celastrol and Withaferin A (WA), two top-ranking compounds identified, markedly inhibited proliferation, arrested the cell cycle and induced apoptosis in leukaemia cells. These compounds also inhibited the viability of primary bone marrow MDS cells. We showed that Celastrol and WA inhibit interleukin-1 receptor-associated kinase 4-mediated nuclear factor kappa-light-chain-enhancer of activated B cells signalling activation in splicing factor mutant MDS and leukaemia cells. Celastrol and WA may represent novel candidate drugs for the treatment of MDS.

Iron-refractory iron deficiency anaemia (IRIDA) is a rare hereditary microcytic anaemia characterized by partial or complete resistance to oral iron supplementation, caused by elevated plasma hepcidin levels resulting from pathogenic variants in the TMPRSS6 gene. Although intravenous iron supplementation is often effective, patient responses can vary significantly due to various factors, and potential side effects of this treatment remain unclear. Additionally, evidence-based international guidelines for diagnosing and managing IRIDA are lacking. This review aims to provide patient-tailored treatment strategies, informed by case studies and expert opinion, to address the specific therapeutic needs of both children and adults with IRIDA.

In this study, we collected real-world evidence on the use of pegcetacoplan among 22 Italian patients with paroxysmal nocturnal haemoglobinuria showing suboptimal response to anti-C5 treatments eculizumab and ravulizumab. Most patients exhibited a complete or good response as per the criteria of the European Bone Marrow Transplant group (Risitano et al. Front Immunol 2019) and median haemoglobin improvement from baseline was +3.6 g/dL. During the 6-month follow-up, 27% of patients displayed a breakthrough haemolytic event mainly managed with supportive treatment. No thromboses occurred.

Acute myeloid leukaemia (AML) remains a deadly disease, largely due to the persistence of drug-resistant leukaemia-initiating cells (LICs) which promote relapse. Therefore, effective therapies must target LICs. Patient-derived xenografts (PDXs) are valuable for testing new therapies, though establishing AML PDX models is challenging. Two humanized mouse strains, MISTRG and NRGS, have been developed for this purpose. In this study, we show both are suitable strains for the development of AML PDXs; however, MISTRG-derived PDXs contain 10 times higher LIC frequencies than NRGS-derived PDXs. These differences have crucial implications for preclinical AML therapy testing and modelling relapse models of the disease.

This nationwide cohort study provides a comprehensive overview of maternal and perinatal outcomes associated with sickle cell disease (SCD) during pregnancy. Using the French national health database, all singleton pregnancy-related hospital discharges from 2013 to 2020 in women aged 15-55 (n = 5 752 080) were selected. Of these, 1022 births were to women with SCD, 308 of whom were on long-term treatment, that is, hydroxyurea (HU) and/or transfusion programme. Pregnancies with SCD were more likely to involve pre-eclampsia (9.6% vs. 1.7%; p < 0.001), pulmonary embolism (0.70% vs. 0.02%; p < 0.001), caesarean sections (52.8% vs. 18.2%; p < 0.001) and postpartum haemorrhage (8.3% vs. 4.1%; p < 0.001) compared to pregnancies without SCD. Preterm birth (<37 weeks) was much more common in women with SCD (28.5% vs. 5.6%). Infants born to women with SCD faced greater adverse neonatal outcomes (22.4% vs. 8.0%; p < 0.001). Although untreated SCD was linked to fewer complications than long-term treated SCD, both conditions presented greater risks compared with pregnancies without SCD. Unexpectedly, babies born to women with SCD had a higher incidence of congenital abnormalities (6.3% vs. 3.4%; p < 0.001), not attributed to HU use. Overall, despite advances in SCD management, pregnancy in SCD remains a high-risk condition, for both mothers and babies.

Systemic light chain (AL) amyloidosis is an incurable disorder caused by extra-cellular deposition of light-chain aggregates in critical organs. An immunomodulatory agent-based quadruplet including anti-CD38 therapy has not been investigated as a first-line treatment in AL amyloidosis. We report the UK experience of daratumumab-bortezomib-thalidomide-dexamethasone for the first-line treatment of AL amyloidosis. Consecutive patients with a new diagnosis of systemic AL between 2021 and 2023 were retrospectively reviewed from the UK National Amyloidosis Centre database. One hundred and two patients were included; median age was 61 years, involved free light-chain concentration 234 mg/L, 65% had cardiac and 63% renal involvement with modified Mayo stage I/II/IIIa/IIIb in 24%/36%/21% and 19% respectively. A median of 6 cycles was delivered. By intention-to-treat analysis, best haematological overall response rate was 97%: complete response at 65%, very good partial response at 22%, partial response at 11% and no response at 3%. At 6- and 12-month time points from treatment initiation, best cardiac response rates were 39% and 45%, respectively, for evaluable patients. At a median duration of 18 months follow-up, the estimated 1-year overall survival was 89% (95% confidence interval [CI] 81-94) and treatment-free survival/death was 82% (95% CI 73-89). We demonstrate efficacy in this real-world population with comparable results to the gold standard, daratumumab-bortezomib-cyclophosphamide-dexamethasone.