Mattia Algeri

Cleft palate is a congenital anomaly that causes functional and esthetic challenges, and the hard palate is essential for feeding, speech, and separation of the oral and nasal cavities. Yet, current reconstructive techniques do not restore its bony component. Building on previous in vitro work showing that decellularized palatal mucoperiosteum, microperforated with Quantum Molecular Resonance (QMR^®) technology and recellularized with mesenchymal stem cells, preserves the collagen microenvironment, supports engraftment, and shows osteoinductive potential, this study evaluated the early feasibility and regenerative potential of bioengineered mucoperiosteal scaffolds (BEMS) in Landrace pigs model. Bone marrow was collected from recipient pigs to isolate pBM-MSCs. Donor palatal mucoperiosteum was decellularized, microperforated, and recellularized with these cells to generate BEMS. After surgical creation of a cleft palate, four pigs received BEMS, and two controls underwent standard palatoplasty. At one month, scaffold-treated animals showed early mucosal and osseous regeneration, including neo-epithelium, connective tissue, and new bone formation, without clinical or routine histological signs of acute rejection. SPARC (Secreted protein acidic and rich in cysteine) expression supported osteogenic activity. Regenerated palates were stable and fracture-resistant, whereas controls showed incomplete repair and fractures. These findings suggest that BEMS may address limitations of conventional palatal reconstruction and support further investigation for human palatal bone regeneration.

The therapeutic landscape of β‐thalassemia has evolved rapidly over the past decade, shifting from a historical reliance on transfusion support and iron chelation toward disease‐modifying and potentially curative therapies. This review summarizes the clinical development of novel treatments for both non‐transfusion‐dependent and transfusion‐dependent β‐thalassemia, including approved therapies, agents in active development, and programs that have been discontinued. Disease‐modifying strategies have focused on improving ineffective erythropoiesis, correcting iron dysregulation, and restoring red blood cell metabolism. Luspatercept and mitapivat have demonstrated clinically meaningful improvements in hemoglobin levels and reduction of transfusion burden and are now approved in multiple jurisdictions. Additional pyruvate kinase activators, such as etavopivat, are undergoing clinical evaluation. Curative approaches have advanced substantially through gene addition, gene editing, and base editing technologies. Approved therapies, including betibeglogene autotemcel and exagamglogene autotemcel, have achieved high rates of durable transfusion independence, while emerging platforms aim to further improve efficacy, safety, and accessibility. At the same time, several promising approaches targeting fetal hemoglobin induction, iron metabolism, and ineffective erythropoiesis have failed to demonstrate sufficient clinical benefit despite preclinical proof of concept, highlighting the complexity of therapeutic development in β‐thalassemia. Future priorities include refining patient selection, generating real‐world and comparative effectiveness data, developing clinically meaningful response criteria, expanding pediatric access, and addressing the substantial cost and accessibility challenges associated with novel therapies.

The optimal busulfan exposure window in pediatric patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (HSCT) remains to be defined. We identify this window for patients receiving busulfan within the prospective international, randomized controlled phase 3 ALLSCTped 2012 FORUM trial. We included 145 participants receiving fludarabine-busulfan-thiotepa conditioning, with available busulfan plasma levels. Busulfan exposure was estimated using a validated pediatric population pharmacokinetic model. Primary outcomes were event-free survival (EFS) and graft-versus-host disease-free relapse-free survival (GRFS). Patients were aged between 0.5 and 19.5 years, with a median follow-up of 5.0 years. The optimal busulfan exposure was defined as area under busulfan concentration curve (cAUC) of 73.3 to 98.0 mg.h/L based on EFS and GRFS. Patients with nonoptimal exposure had lower EFS (hazard ratio [HR], 1.93; p = 0.008) and GRFS (HR, 2.01; p = 0.002). Underexposure (cAUC 98.0 mg.h/L) with an increased risk of treatment-related toxicities and graft-versus-host disease. Patients with optimal busulfan exposure showed no differences in EFS, GRFS, overall survival, or relapse with post hoc matched total-body irradiation (TBI) recipients (n = 51 in each group). This study identifies a favorable busulfan exposure window for pediatric patients with ALL undergoing HSCT from an HLA-matched donor. Therapeutic drug monitoring for optimized personalized busulfan dosing improves HSCT outcomes and might be validated for use as an alternative to irradiation. This trial was registered at EudraCT as 2012-003032-22 and on www.ClinicalTrials.gov as NCT01949129.

Human recombination-activating gene (RAG) deficiency can manifest with distinct clinical and immunological phenotypes. By applying a multiomics approach to a large group of RAG -mutated patients, we aimed at characterizing the immunopathology associated with each phenotype. Although defective T and B cell development is common to all phenotypes, patients with hypomorphic RAG variants can generate T and B cells with signatures of immune dysregulation and produce autoantibodies to a broad range of self-antigens, including type I interferons. T helper 2 (T _H 2) cell skewing and a prominent inflammatory signature characterize Omenn syndrome, whereas more hypomorphic forms of RAG deficiency are associated with a type 1 immune profile both in blood and tissues. We used cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) analysis to define the cell lineage–specific contribution to the immunopathology of the distinct RAG phenotypes. These insights may help improve the diagnosis and clinical management of the various forms of the disease.

BACKGROUND: Severe forms of idiopathic nephrotic syndrome (INS) require prolonged immunosuppressive therapies and repeated courses of high-dose glucocorticoids. Mesenchymal stromal cells (MSCs) have promising immunomodulatory properties that may be employed therapeutically to reduce patient exposure to medications and their side effects. METHODS: We performed a phase I open-label trial assessing safety and feasibility of autologous bone marrow–derived MSCs (BM-MSCs) in children and young adults with severe forms of steroid-dependent nephrotic syndrome. Following autologous BM-MSC preparation and infusion, oral immunosuppression was tapered. Safety, efficacy, and immunomodulatory effects in vivo were monitored for 12 months. RESULTS: Sixteen patients (10 children, 6 adults) were treated. Adverse events were limited and not related to BM-MSC infusions. All patients relapsed during follow-up, but in the 10 treated children, time to first relapse was delayed ( P = 0.02) and number of relapses was reduced ( P = 0.002) after BM-MSC infusion, compared with the previous 12 months. Cumulative prednisone dose was also reduced at 12 months compared with baseline ( P < 0.05). No treatment benefit was observed in adults. In children, despite tapering of immunosuppression, clinical benefit was mirrored by a significant reduction in total CD19+, mature, and memory B cells and an increase in regulatory T cells in vivo up to 3–6 months following BM-MSC infusion: CONCLUSION: Treatment with autologous BM-MSCs is feasible and safely reduces relapses and immunosuppression at 12 months in children with severe steroid-dependent INS. Immunomodulatory studies suggest that repeating MSC infusions at 3–6 months may sustain benefit. TRIAL REGISTRATION: EudraCT 2016-004804-77. FUNDING: AIFA Ricerca Indipendente 2016-02364623.

Hematopoietic stem cell transplantation (HSCT) is often the only curative treatment option for patients suffering from various types of malignant diseases and some non-cancerous conditions. Nevertheless, it is associated with a high risk of complications leading to transplant-related mortality and long-term morbidity. An increasing number of therapeutic and prevention strategies have been developed over the last few years to tackle the complications arising in patients receiving an HSCT. These strategies have been mainly carried out in adults and some are now being translated into children. In this manuscript, we review the recent advancements in the development and implementation of treatment options for post-HSCT non-infectious complications in pediatric patients with leukemia and other non-malignant conditions, with a special attention on the new agents available within clinical trials. We focused on the following conditions: graft failure, prevention of relapse and early interventions after detection of minimal residual disease positivity following HSCT in acute lymphoblastic and myeloid leukemia, chronic graft versus host disease, non-infectious pulmonary complications, and complications of endothelial origin.