Umbilical cord blood (UCB) is a rich source of hematopoietic stem and progenitor cells (HSPCs), mesenchymal stromal cells (MSCs), and diverse immune cell subsets with unique developmental and functional properties. These characteristics have established UCB as an important graft source for hematopoietic stem cell transplantation (HSCT) and an emerging platform for next-generation immunotherapies and regenerative applications. Importantly, cord blood transplantation remains most widely used in pediatric patients, who constitute the majority of UCB transplant recipients due to favorable tissue compatibility and hematopoietic reconstitution kinetics and the suitability of single-unit UCB grafts. Advances in donor recruitment, processing, cryopreservation, ex vivo expansion, and cell engineering continue to broaden the clinical utility of UCB while addressing historical limitations related to cell dose and engraftment kinetics. This review summarizes current biological insights, key aspects of banking infrastructure and the regulatory landscape, established and investigational therapeutic uses, and the evolving challenges and opportunities that will shape the future integration of UCB usage beyond graft source for HSCT.

Hepatic ischemia-reperfusion injury (IRI) is a complex event influenced by interconnected immune and metabolic processes. Steatotic livers are especially sensitive to IRI, but the crosstalk between innate inflammatory responses and lipid metabolic dysregulation in this context is not well understood. Using transcriptomic profiling in a murine high-fat diet (HFD) model, we assessed immune and metabolic responses to hepatic IRI and examined the effects of N-acetylcysteine (NAC). In steatotic livers, IRI induced the upregulation of inflammatory mediators, including TLR/NF-κB-associated genes (Tlr2, Tlr4, Irf1) and neutrophil-associated genes (S100a8, S100a9, Lcn2), accompanied by the downregulation of lipid and cholesterol metabolism-related genes, including Cyp7a1, Cyp8b1, Cyp27a1, and Hmgcr. NAC supplementation attenuated inflammatory gene expression and restored key lipid biosynthetic regulators. We then performed targeted lipidomic analysis to determine whether NAC-mediated transcriptional changes were reflected at the lipid level and observed a significant increase in total phosphatidylcholine and sphingomyelin in steatotic livers following IRI. Finally, to assess the contribution of innate immune cells to hepatic IRI, we quantified neutrophils and macrophages in HFD+NAC IRI and HFD IRI livers. We found that NAC supplementation reduced hepatic neutrophil accumulation and markedly decreased LCN2 expression following IRI.

BACKGROUND AIMS:Post-thaw viability of cryopreserved hematopoietic progenitor cell (HPC) products is a critical quality attribute, yet testing practices vary widely across institutions. We conducted an international survey followed by a two-phase multicenter validation study to characterize current practices and assess inter-laboratory comparability using harmonized protocols. METHODS:In Phase 1, cord blood-derived HPC units were distributed to six centers for post-thaw viability testing. In Phase 2, cryopreserved HPC-apheresis cell product samples were distributed to three centers for viability assessment by flow cytometry under paired red blood cell lysis and non-lysis conditions at 0-120 min post-thaw. Center performance was evaluated using standardized deviation index (SDI) analysis. RESULTS:Survey results revealed that 55.9% of respondents performed routine post-thaw viability testing, with considerable variability in methods (57.9% flow cytometry, 42.1% Trypan Blue) and acceptance thresholds (ranging from 40% to ≥90%). In Phase 1, center-level mean SDIs for CD34⁺ and CD45⁺ viabilities were generally within ±2 after outlier removal, indicating acceptable inter-laboratory consistency. In Phase 2, viabilities remained stable from 0 to 120 min post-thaw under both conditions. CONCLUSIONS:This multicenter validation demonstrates that harmonized thawing and 7-AAD-based flow cytometry protocols can achieve good inter-laboratory comparability for cryopreserved HPC products. The data support SDI-based performance monitoring, pragmatic use of Trypan Blue where flow cytometry is unavailable, and operational flexibility for post-thaw testing within a 2-h window. These findings provide a foundation for consensus guidelines on post-thaw viability assessment.

AIMS:Combined renal and islet xenotransplantation could provide a durable treatment for end-stage diabetic nephropathy. In this feasibility-focused study, we evaluated two complementary approaches for clinical translation: (1) pre-vascularized composite islet-kidney (I-K) grafts and (2) sequential islet-after-kidney xenotransplantation with vascularized thymic lobe (VTL) co-transplantation as an adjunct immune tolerance strategy. METHODS:Composite I-K grafts were generated in nine MHC-matched, minor-antigen-mismatched miniature swine pairs by implanting adult porcine islets beneath the renal capsule of juvenile kidney donors followed by pre-vascularization under tacrolimus-based immunosuppression. Separately, three baboons underwent GalTKO.hCD55 kidney and VTL xenotransplantation, followed by streptozocin-induced diabetes and intraportal adult porcine islet infusion from a separate donor. Renal/metabolic function, porcine C-peptide, histology, and immune profiling were assessed. RESULTS:Composite I-K grafts demonstrated limited islet survival with peri-islet inflammation on histology at the graft preparation stage and were not advanced to pig-to-NHP xenotransplantation in this study. Sequential islet-after-kidney transplantation restored insulin-independent euglycemia in all recipients. Porcine C-peptide was detectable in the long-term survivor with intrahepatic insulin-positive islets at necropsy. Infection-associated thrombotic microangiopathy limited survival in two animals; in the 180-day survivor, anti-porcine hypo-responsiveness and evidence of thymopoiesis within the VTL graft were observed. CONCLUSIONS:In this limited series, sequential islet-after-kidney xenotransplantation restored metabolic control and represents a promising translational strategy for diabetic nephropathy.

Introduction and Objective: Immune-mediated rejection remains a major barrier to durable pancreatic islet transplantation for type 1 diabetes. Mesenchymal stromal/stem cells (MSCs) possess immunomodulatory properties, and engineering MSCs to overexpress alpha-1 antitrypsin (AAT) may enhance their therapeutic potential. This study evaluated whether co-transplantation of human islets with AAT-overexpressing MSCs (AAT-MSCs) improves graft survival and modulates human immune responses in a humanized mouse model. Methods: Humanized-NSG mice were generated by irradiation and transplantation of human CD34+ hematopoietic stem/progenitor cells to reconstitute human T and B cells. Diabetic mice received intrahepatic transplantation of human islets alone or with AAT-MSCs and were monitored for six weeks. Graft function and immune responses were assessed through blood glucose monitoring, serum immunoglobulin measurements, immune cell phenotyping, graft histology, and in vitro assays evaluating B cell differentiation and cytokine production. Results: Co-transplantation with AAT-MSCs significantly improved glycemic control, prolonged islet graft survival, and reduced rejection compared with islets alone. These effects were associated with reduced serum IgM levels, which inversely correlated with graft rejection, and expansion of regulatory B cells. This was accompanied by suppression of Th1, Th17, and cytotoxic T cell responses. Histological analysis showed improved insulin preservation and enrichment of IL-10+ cells in co-transplant grafts. In vitro, AAT-MSCs promoted regulatory B cell differentiation, shifted cytokine production toward IL-10 rather than IL-6, and protected human islets from activated B cell-mediated cytotoxicity. Conclusion: AAT-MSCs co-transplantation promotes immune tolerance and sustains human islet graft function, highlighting its potential to improve clinical islet transplantation and reduce reliance on systemic immunosuppression. Disclosure W. Gou: None. J. Kim: None. T.N. Yeung: None. W. Cui: None. C. Strange: Other - CEO and owner working on stem cell therapies for diabetes; Current; Exollent Therapeutics. H. Wang: None. Funding National Institutes of Health (R01 DK105183, DK120394, DK118529, and DK125464) and the Department of Veterans Affairs (VA-ORD BLR&D Merit I01BX004536)

BACKGROUND:The field of cell and gene therapy (CGT) is expanding at a rapid rate. CGT workforce shortage is a growing concern, and high-quality training programs are essential to keep up with the increasing demand for qualified CGT technologists. METHODS:A working group within the International Society for Cell & Gene Therapy (ISCT) Laboratory Practices Committee developed an ISCT Lab Practices Committee Survey on Cell and Gene Therapy Technologist Training to gather information on CGT laboratory technologist training practices. RESULTS:The survey results characterize the training landscape of CGT laboratory professionals and highlight the lack of standardization in CGT training. CONCLUSIONS:The heterogeneity of training practices among CGT laboratories can make it challenging to design, implement or assess a training program at an individual laboratory. To help navigate this challenge, the authors provide a high-level overview of the resources available for CGT training, describe several potential staff training models, outline a sample curriculum, and highlight some of the key practical considerations for implementing a CGT technologist training program in one's institution.

Combined islet and kidney xenotransplantation for the treatment of diabetic nephropathy represents a compelling and increasingly relevant therapeutic possibility for an ever-growing number of patients who would benefit from both durable renal replacement and cure of the underlying cause of their renal insufficiency: diabetes. Here we briefly review immune barriers to islet transplantation, highlight preclinical progress in the field, and summarize our experience with combined islet and kidney xenotransplantation, including both challenges with islet-kidney composite grafts as well as our recent success with sequential kidney followed by islet xenotransplantation in a pig-to-baboon model.

Graft-versus-host disease (GvHD) remains a potentially fatal complication following intestinal transplant (ITx). Over the past decade, advances in the understanding of the pathophysiology of this complex immunological phenomenon have led to the reassessment of the host systemic immune response and have created a gateway for novel preventive and therapeutic strategies. Although sufficient evidence dictates the use of corticosteroids as a first-line option, the treatment for refractory disease remains contentious and lacks a standardized therapeutic approach. Timely diagnosis remains crucial, and the advent of chimerism detection and immunological biomarkers have transformed the identification, prognostication, and potential for survival after GvHD in ITx. The objectives of the following review aim to discuss the clinical and diagnostic features, pathophysiology, advances in immune biomarkers, as well as therapeutic opportunities in the prevention and treatment of GvHD in ITx.

Background: Neutrophil granulocytes are essential components of innate immune response. An absolute number of neutrophils are a fundamental indicator of host defense. With increasing severity of neutropenia, either due to the disease or as a result of chemotherapy for hematologic malignancies, there is an exponential increase in the risk of severe infection. In such conditions, granulocyte transfusion is considered a potential therapeutic option due to its phagocytic properties. The study was undertaken to analyze data of granulocyte collections and transfusions in resource-constrained Settings. Methods: In this observational prospective study, granulocytes were harvested by combined administration of granulocyte colony-stimulating factors and dexamethasone mobilization and transfused to severely neutropenic patients. Data on granulocyte collections and transfusion, various determinants of donor, and procedural characteristics and patient outcomes, with respect to 30-day mortality, were analyzed. Results: After granulocyte transfusion, patients' posttransfusion white blood cell and neutrophils increased significantly. Higher platelet counts in the harvested products resulted into significant increment of patients' platelet count and markedly reduced demands of platelet transfusions, reducing chances of alloimmunization. Eighty-five percent of patients could be saved, showed improvements in their clinical conditions, and were discharged from hospital in stable condition. Conclusion: Granulocyte transfusions are an important therapeutic modality in neutropenic patients with resistant infections, until spontaneous recovery of neutrophil count occurs in patients. Cost Reduction of some of the resources should be considered for LMIC as lower price will encourage more facilities willing to offer similar procedures to aid patients. Training workforce for new and novel processes is need of hour and will add value by equipping LMIC facilities in serving the patients. Granulocyte transfusions are life-saving tool and found to be safe and well tolerated by recipients. They can play a vital role in improving outcomes and saving patients in resource-constraint countries, where there is increasing emergence of multidrug-resistant bacterial infections.

Mesenchymal stem cells are a potential therapeutic candidate for cerebral infarction due to their anti-inflammatory proprieties. However, ensuring the engraftment of sufficient cells into the affected brain area remains a challenge. Herein, magnetic targeting techniques were used for the transplantation of a large number of cells noninvasively. Mice subjected to pMCAO surgery were administered MSCs labeled or not with iron oxide@polydopamine nanoparticles by tail vein injection. Iron oxide@polydopamine particles were characterized by transmission electron microscopy, and labeled MSCs were characterized by flow cytometry and their differentiation potential was assessed in vitro. Following the systemic injection of iron oxide@polydopamine-labeled MSCs into pMCAO-induced mices, magnetic navigation increased the MSCs localization to the brain lesion site and reduced the lesion volume. Treatment with iron oxide@polydopamine-labeled MSCs also significantly inhibited M1 microglia polarization and increased M2 microglia cell infiltration. Furthermore, western blotting and immunohistochemical analysis demonstrated that microtubule-associated protein 2 and NeuN levels were upregulated the brain tissue of mice treated with iron oxide@polydopamine-labeled MSCs. Thus, iron oxide@polydopamine-labeled MSCs attenuated brain injury and protected neurons by preventing pro-inflammatory microglia activation. Overall, the proposed iron oxide@polydopamine-labeled MSCs approach may overcome the major drawback of the conventional MSCs therapy for the treatment of cerebral infarction.

Maple syrup urine disease (MSUD) is an intoxication-type inherited metabolic disorder in which hyperleucinemia leads to brain swelling and death without treatment. MSUD is caused by branched-chain alpha-ketoacid dehydrogenase deficiency due to biallelic loss of the protein products from the genes BCKDHA, BCKDHB, or DBT, while a distinct but related condition is caused by loss of DLD. In this case series, eleven individuals with MSUD caused by two pathogenic variants in DBT are presented. All eleven individuals have a deletion of exon 2 (delEx2, NM_001918.3:c.48_171del); six individuals are homozygous and five individuals are compound heterozygous with a novel missense variant (NM_001918.5:c.916 T > C [p.Ser306Pro]) confirmed to be in trans. Western Blot indicates decreased amount of protein product in delEx2;c.916 T > C liver cells and absence of protein product in delEx2 homozygous hepatocytes. Ultrahigh performance liquid chromatography-tandem mass spectrometry demonstrates an accumulation of branched-chain amino acids and alpha-ketoacids in explanted hepatocytes. Individuals with these variants have a neonatal-onset, non-thiamine-responsive, classical form of MSUD. Strikingly, the entire cohort is derived from families who immigrated to the Washington, DC, metro area from Honduras or El Salvador suggesting the possibility of a founder effect.