A Pilot Phase I Trial of Allogeneic Umbilical Cord Tissue-Derived Mesenchymal Stromal Cells in Neonates With Hypoxic-Ischemic Encephalopathy

The revolutionary role of placental derivatives in biomedical research

The human placenta is a transient yet crucial organ that plays a key role in sustaining the relationship between the maternal and fetal organisms. Despite its historical classification as "biowaste," placental tissues have garnered increasing attention since the early 1900s for their significant medical potential, particularly in wound repair and surgical application. As ethical considerations regarding human placental derivatives have largely been assuaged in many countries, they have gained significant attention due to their versatile applications in various biomedical fields, such as biomedical engineering, regenerative medicine, and pharmacology. Moreover, there is a substantial trend toward various animal product substitutions in laboratory research with human placental derivatives, reflecting a broader commitment to advancing ethical and sustainable research methodologies. This review provides a comprehensive examination of the current applications of human placental derivatives, explores the mechanisms behind their therapeutic effects, and outlines the future potential and directions of this rapidly advancing field.

Neuroprotection for neonatal hypoxic-ischemic encephalopathy: A review of novel therapies evaluated in clinical studies

Therapeutic hypothermia is an effective therapy for moderate-to-severe hypoxic-ischemic encephalopathy (HIE) in infants born at term or near-term in high-resource settings. Yet there remains a substantial proportion of infants who do not benefit or who will have significant disability despite therapeutic hypothermia. Novel investigational therapies that may confer additional neuroprotection by targeting known pathogenic mechanisms of hypoxic-ischemic brain injury are under development. This review focuses on putative neuroprotective agents that have shown promise in animal models of HIE, and that have been translated to clinical studies in neonates with HIE. We include agents that have been studied both with and without concurrent therapeutic hypothermia. Our review therefore addresses not just neonatal HIE in high-resource countries where therapeutic hypothermia is the standard of care, but also neonatal HIE in low- and middle-income countries where therapeutic hypothermia has been shown to be ineffective, and where the greatest burden of HIE-related morbidity and mortality exists.

Potential Applications of Umbilical Cord Blood-Derived Cells in Neonatal Diseases

Umbilical cord blood (UCB) has garnered attention as a potentially valuable resource in neonatal medicine. Blood from the cord contains a rich population of stem and progenitor cells, including hematopoietic stem cells, mesenchymal stromal cells, and endothelial progenitor cells, each offering unique therapeutic potential. Early clinical studies and preclinical trials have suggested that these cells may be able to promote tissue repair, provide neuroprotection, and modulate the immune system, potentially providing promising therapeutic avenues for neonates with limited treatment options. Current research has focused on the safety, feasibility, and preliminary efficacy of UCB-based therapies, particularly in neonates with brain injuries, lung diseases, and hematological disorders. Despite positive early results, the field is still evolving, and large-scale clinical trials are underway to further evaluate the potential of UCB-derived cells in neonates. In this review, we examine the diverse roles of UCB-derived cells in potentially treating neonatal diseases such as anemia, intraventricular hemorrhage, hypoxic-ischemic encephalopathy, and bronchopulmonary dysplasia. We also discuss future directions for the application of UCB-derived cells in transfusion and regenerative medicine.

Cell-based therapies in preclinical models of necrotizing enterocolitis: a systematic review and meta-analysis

Necrotizing enterocolitis (NEC) remains an incurable gut complication of prematurity with significant morbidity and mortality. Cell therapies, including mesenchymal stromal cells (MSCs), may be a promising treatment given their anti-inflammatory and regenerative potential. We assessed the effect of MSCs and other cell therapies (not classified as MSCs) on incidence, severity, and mortality in preclinical models of NEC. Bibliographic and gray literature searches yielded 17 371 records with 107 full-text articles assessed and ultimately 16 studies were included. These studies featured only rodents NEC models via combination of hyperosmolar feeds, hypoxia, hypothermia, or lipopolysaccharides. Ten studies used interventions with MSCs. Only 2 met the minimal criteria to define MSCs proposed by the International Society for Cell & Gene Therapy (ISCT). The overall risk of bias was assessed as high partly due to paucity of data with important gaps in reporting, reinforcing the importance of rigorous research framework, appropriate cell-therapy and outcome reporting in preclinical research. A reduction in the incidence of NEC (odds ratio [OR] 0.32, 95% CI [0.17, 0.62]), severe NEC (OR 0.30, 95% CI [0.18, 0.50]), and mortality (OR 0.30, 95% CI [0.16, 0.55]) was noted with MSCs treatment, seemingly more pronounced for ISCT-defined (ISCT+) MSCs. Amniotic fluid stem cells, neural stem cells, and placenta stem cells also showed a reduction in these measures. Given their accessibility (ie, umbilical cord) and proven safety profile in extremely preterm infants, our analysis provides a foundation for considering MSCs as promising candidate that requires further evaluation for the treatment of NEC.

Hypoxic-Ischemic Encephalopathy: Pathogenesis and Promising Therapies

Hypoxic-ischemic encephalopathy (HIE) is a brain lesion caused by inadequate blood supply and oxygen deprivation, often occurring in neonates. It has emerged as a grave complication of neonatal asphyxia, leading to chronic neurological damage. Nevertheless, the precise pathophysiological mechanisms underlying HIE are not entirely understood. This paper aims to comprehensively elucidate the contributions of hypoxia-ischemia, reperfusion injury, inflammation, oxidative stress, mitochondrial dysfunction, excitotoxicity, ferroptosis, endoplasmic reticulum stress, and apoptosis to the onset and progression of HIE. Currently, hypothermia therapy stands as the sole standard treatment for neonatal HIE, albeit providing only partial neuroprotection. Drug therapy and stem cell therapy have been explored in the treatment of HIE, exhibiting certain neuroprotective effects. Employing drug therapy or stem cell therapy as adjunctive treatments to hypothermia therapy holds great significance. This article presents a systematic review of the pathogenesis and treatment strategies of HIE, with the goal of enhancing the effect of treatment and improving the quality of life for HIE patients.

Can miRNAs in MSCs-EVs Offer a Potential Treatment for Hypoxic-ischemic Encephalopathy?

Neonatal hypoxic-ischemic encephalopathy (HIE) is a critical condition resulting from impaired oxygen and blood flow to the brain during birth, leading to neuroinflammation, neuronal apoptosis, and long-term neurological deficits. Despite the use of therapeutic hypothermia, current treatments remain inadequate in fully preventing brain damage. Recent advances in mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) offer a novel, cell-free therapeutic approach, as these EVs can cross the blood-brain barrier (BBB) and deliver functional microRNAs (miRNAs) to modulate key pathways involved in inflammation and neuroprotection. This review examines how specific miRNAs encapsulated in MSC-EVs-including miR-21, miR-124, miR-146, and the miR-17-92 cluster-target the complex inflammatory responses that drive HIE pathology. By modulating pathways such as NF-κB, STAT3, and PI3K/Akt, these miRNAs influence neuroinflammatory processes, reduce neuronal apoptosis, and promote tissue repair. The aim is to assess the therapeutic potential of miRNA-loaded MSC-EVs in mitigating inflammation and neuronal damage, thus addressing the limitations of current therapies like therapeutic hypothermia.

Advances in mesenchymal stem cell-centered stem cell therapy in the treatment of hypoxic-ischemic injury

Hypoxic-ischemic brain damage (HIBD) is a leading cause of neonatal death and neurological dysfunction for which no particularly effective treatment is available. Stem cells possess multi-directional differentiation potential and can secrete a variety of cytokines. They not only have the ability to replace tissue and repair lesions but also improve neurological damage caused by HIBD through paracrine mechanisms, including anti-apoptosis, reduction of inflammation, and promotion of endogenous repair. Recently, as research on stem cells, particularly mesenchymal stem cells, has deepened, the application of stem cells in treating HIBD has become a prominent research topic, yielding fruitful results, particularly regarding the neuroprotective effects and mechanisms of the stem cell paracrine pathway. With advances in stem cell injection, distribution, and biomaterial incorporation, applications of stem cells have become more widespread and comprehensive. This review summarizes and discusses the research progress on stem cells in HIBD treatment to provide theoretical support for HIBD treatment and enhance the feasibility of clinical translation.

Safety and tolerability of a Muse cell-based product in neonatal hypoxic-ischemic encephalopathy with therapeutic hypothermia (SHIELD trial)

Hypoxic-ischemic encephalopathy (HIE), associated with high mortality and neurological sequelae, lacks established treatment except therapeutic hypothermia. Clinical-grade multilineage-differentiating stress-enduring (Muse) cells (CL2020) demonstrated safety and efficacy in nonclinical HIE rat models, thereby leading to an investigator-initiated clinical trial to evaluate CL2020 safety and tolerability in neonatal HIE as a single-center open-label dose-escalation study with 9 neonates with moderate-to-severe HIE who received therapeutic hypothermia. Each patient received a single intravenous injection of CL2020 cells between 5 and 14 days of age. The low-dose (3 patients) and high-dose (6 patients) groups received 1.5 × 106 and 1.5 × 107 cells/dose, respectively. The occurrence of any adverse event within 12 weeks following CL2020 administration was the primary endpoint of this trial. No significant changes in physiological signs including heart rate, blood pressure, and oxygen saturation were observed during or after administration. The only adverse event that may be related to cell administration was a mild γ-glutamyltransferase level elevation in one neonate, which spontaneously resolved without any treatment. All patients enrolled in the trial survived, and normal developmental quotients (≥ 85) in all 3 domains of the Kyoto Scale of Psychological Development 2001 were observed in 67% of the patients in this trial. CL2020 administration was demonstrated to be safe and tolerable for neonates with HIE. Considering the small number of patients, a randomized controlled confirmatory study is warranted to verify these preliminary findings and evaluate the efficacy of this therapy.

Non-nutritional use of human milk as a therapeutic agent in neonates: Brain, gut, and immunologic targets

Human milk (HM) exposure improves short- and long-term outcomes for infants due to a complex milieu of bioactive, stem cell, anti-inflammatory, anti-microbial, and nutritive components. Given this remarkable biologic fluid, non-nutritional utilization of HM as a targeted therapeutic is being explored in pre-clinical and clinical studies. This article describes recent research pertinent to non-nutritional uses of HM for neurologic, gastrointestinal, and infectious pathologies in neonates, as well as future directions.

Long-Term Outcomes Following Hypoxic Ischemic Encephalopathy

Hypoxic ischemic encephalopathy (HIE) is the most common cause of neonatal encephalopathy and results in significant morbidity and mortality. Long-term outcomes of the condition encompass impairments across all developmental domains. While therapeutic hypothermia (TH) has improved outcomes for term and late preterm infants with moderate to severe HIE, trials are ongoing to investigate the use of TH for infants with mild or preterm HIE. There is no evidence that adjuvant therapies in combination with TH improve long-term outcomes. Numerous trials of various adjuvant therapies are underway in the quest to further improve outcomes for infants with HIE.

Mesenchymal Stromal Cell therapy for Hypoxic Ischemic Encephalopathy: Future directions for combination therapy with hypothermia and/or melatonin

Hypoxic ischemic encephalopathy (HIE) remains a leading cause of neonatal mortality and lifelong disability across the world. While therapeutic hypothermia (HT) is beneficial, it is only partially protective and adjuvant treatments that further improve outcomes are urgently needed. In high-income countries where HT is standard care, novel treatments are tested in conjunction with HT. Mesenchymal stromal cells (MSC) represent a paradigm shift in brain protection, uniquely adapting to the host cellular microenvironment. MSC have low immunogenicity and potent paracrine effects stimulating the host tissue repair and regeneration and reducing inflammation and apoptosis. Preclinical studies in perinatal brain injury suggest that MSC are beneficial after hypoxia-ischemia (HI) and most preclinical studies of MSC with HT show protection. Preclinical and early phase clinical trials have shown that allogenic administration of MSC to neonates with perinatal stroke and HIE is safe and feasible but further safety and efficacy studies of HT with MSC in these populations are needed. Combination therapies that target all stages of the evolution of injury after HI (eg HT, melatonin and MSC) show promise for improving outcomes in HIE.

The fulfilled promise and unmet potential of umbilical cord blood

PURPOSE OF REVIEW

Here, we review classic and emerging uses of umbilical cord blood and highlight strategies to improve its utility, focusing on selection of the appropriate units and cell types for the intended applications.

RECENT LITERATURE

Recent studies have shown advancements in cord blood cell utility in a variety of cellular therapies and have made strides in elucidating manners to select the best units for therapy and target new ways to improve the various cell subpopulations for their respective applications.

SUMMARY

Umbilical cord blood is a proven source of cells for hematopoietic cell transplantation and research and is an important potential source for additional cellular therapies. However, cord blood utility is limited by low "doses" of potent cells that can be obtained from individual units, a limitation that is specific to cord blood as a donor source. In addition to traditional CD34 + progenitor cells, cord blood lymphocytes are being pursued as therapeutic entities with their own unique properties and characteristics. Thus, selection of ideal units depends on the intended therapeutic entity and target, and identification of differential potency parameters is critical to drive effective banking strategies accommodating successful clinical use of cord blood in broader cell therapy settings.

Mesenchymal stromal cells suppress microglial activation and tumor necrosis factor production

BACKGROUND AIMS

White matter diseases are commonly associated with microglial activation and neuroinflammation. Mesenchymal stromal cells (MSCs) have immunomodulatory properties and thus have the potential to be developed as cell therapy for white matter disease. MSCs interact with resident macrophages to alter the trajectory of inflammation; however, the impact MSCs have on central nervous system macrophages and the effect this has on the progression of white matter disease are unclear.

METHODS

In this study, we utilized numerous assays of varying complexity to model different aspects of white matter disease. These assays ranged from an in vivo spinal cord acute demyelination model to a simple microglial cell line activation assay. Our goal was to investigate the influence of human umbilical cord tissue MSCs on the activation of microglia.

RESULTS

MSCs reduced the production of tumor necrosis factor (TNF) by microglia and decreased demyelinated lesions in the spinal cord after acute focal injury. To determine if MSCs could directly suppress the activation of microglia and to develop an efficient potency assay, we utilized isolated primary microglia from mouse brains and the Immortalized MicroGlial Cell Line (IMG). MSCs suppressed the activation of microglia and the release of TNF after stimulation with lipopolysaccharide, a toll-like receptor agonist.

CONCLUSIONS

In this study, we demonstrated that MSCs altered the immune response after acute injury in the spinal cord. In numerous assays, MSCs suppressed activation of microglia and release of the pro-inflammatory cytokine TNF. Of these assays, IMG could be standardized and used as an effective potency assay to determine the efficacy of MSCs for treating white matter disease or other neuroinflammatory conditions associated with microglial activation.

Umbilical cord blood and cord tissue banking as somatic stem cell resources to support medical cell modalities

Human umbilical cord blood (CB) and umbilical cord tissue (UC) are attractive sources of somatic stem cells for gene and cell therapies. CB and UC can be obtained noninvasively from donors. CB, a known source of hematopoietic stem cells for transplantation, has attracted attention as a new source of immune cells, including universal chimeric antigen receptor-T cell therapy (CAR-T) and, more recently, universal CAR-natural killer cells. UC-derived mesenchymal stromal cells (UC-MSCs) have a higher proliferation potency than those derived from adult tissues and can be used anon-HLA restrictively. UC-MSCs meet the MSC criteria outlined by the International Society of Gene and Cellular Therapy. UC-MSCs are negative for HLA-DR, CD80, and CD86 and have an immunosuppressive ability that mitigates the proliferation of activated lymphocytes through secreting indoleamine 2,3-dioxygenase 1 and prostaglandin E2, and the expression of PD-L2 and PD-L1. We established the off-the-shelf cord blood/cord bank IMSUT CORD to support novel cell therapy modalities, including the CB-derived immune cells, MSCs, MSCs-derived extracellular vesicles, biological carriers loaded with chemotherapy drugs, prodrug, oncolytic viruses, nanoparticles, human artificial chromosome, combinational products with a scaffold, bio3D printing, and so on.

Mononuclear cell therapy of neonatal hypoxic-ischemic encephalopathy in preclinical versus clinical studies: a systematic analysis of therapeutic efficacy and study design

Background

Hypoxic-ischemic encephalopathy (HIE) is a devastating condition affecting around 8.5 in 1000 newborns globally. Therapeutic hypothermia (TH) can reduce mortality and, to a limited extent, disability after HIE. Nevertheless, there is a need for new and effective treatment strategies. Cell based treatments using mononuclear cells (MNC), which can be sourced from umbilical cord blood, are currently being investigated. Despite promising preclinical results, there is currently no strong indicator for clinical efficacy of the approach. This analysis aimed to provide potential explanations for this discrepancy.

Methods

A systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. Preclinical and clinical studies were retrieved from PubMed, Web of Science, Scopus, and clinicaltrials.gov using a predefined search strategy. A total of 17 preclinical and 7 clinical studies were included. We analyzed overall MNC efficacy in preclinical trials, the methodological quality of preclinical trials and relevant design features in preclinical versus clinical trials.

Results

There was evidence for MNC therapeutic efficacy in preclinical models of HIE. The methodological quality of preclinical studies was not optimal, and statistical design quality was particularly poor. However, methodological quality was above the standard in other fields. There were significant differences in preclinical versus clinical study design including the use of TH as a baseline treatment (only in clinical studies) and much higher MNC doses being applied in preclinical studies.

Conclusions

Based on the analyzed data, it is unlikely that therapeutic effect size is massively overestimated in preclinical studies. It is more plausible that the many design differences between preclinical and clinical trials are responsible for the so far lacking proof of efficacy of MNC treatments in HIE. Additional preclinical and clinical research is required to optimize the application of MNC for experimental HIE treatment.

Advances in Therapies to Treat Neonatal Hypoxic-Ischemic Encephalopathy

Neonatal hypoxic-ischemic encephalopathy (HIE) is a condition that results in brain damage in newborns due to insufficient blood and oxygen supply during or after birth. HIE is a major cause of neurological disability and mortality in newborns, with over one million neonatal deaths occurring annually worldwide. The severity of brain injury and the outcome of HIE depend on several factors, including the cause of oxygen deprivation, brain maturity, regional blood flow, and maternal health conditions. HIE is classified into mild, moderate, and severe categories based on the extent of brain damage and resulting neurological issues. The pathophysiology of HIE involves different phases, including the primary phase, latent phase, secondary phase, and tertiary phase. The primary and secondary phases are characterized by episodes of energy and cell metabolism failures, increased cytotoxicity and apoptosis, and activated microglia and inflammation in the brain. A tertiary phase occurs if the brain injury persists, characterized by reduced neural plasticity and neuronal loss. Understanding the cellular and molecular aspects of the different phases of HIE is crucial for developing new interventions and therapeutics. This review aims to discuss the pathophysiology of HIE, therapeutic hypothermia (TH), the only approved therapy for HIE, ongoing developments of adjuvants for TH, and potential future drugs for HIE.

A narrative review on treatment strategies for neonatal hypoxic ischemic encephalopathy

Background and Objective

Hypoxic-ischemic encephalopathy (HIE) is a leading cause of death and disability worldwide. Therapeutic hypothermia (TH) represents a significant achievement in the translation of scientific research to clinical application, but it is currently the only neuroprotective treatment for HIE. This review aims to revisit the use of TH for HIE and its longitudinal impact on patient outcomes to readers new to the field of HIE. We discuss how emerging therapies address the broader pathophysiology of injury progression in the neonatal brain days to years after HIE.

Methods

We included full articles and book chapters published in English on PubMed with references to "hypoxic ischemic encephalopathy", "birth asphyxia", "therapeutic hypothermia", or "neonatal encephalopathy". We limited our review to outcomes on term infants and to new therapeutics that are in the second phase of clinical trials.

Key Content and Findings

Despite the use of TH for HIE, mortality remains high. Analysis of longitudinal studies reveals a high incidence of ongoing disability even with the implementation of TH. New therapeutics addressing the secondary phase and the less understood tertiary phase of brain injury are in clinical trials as adjunctive treatments to TH to support additional neurological repair and regeneration.

Conclusions

TH successfully improves outcomes after HIE, and it continues to be optimized. Larger studies are needed to understand its use in mild cases of HIE and if certain factors, such as sex, affect long term outcomes. TH primarily acts in the initial phases of injury, while new pharmaceutical therapies target additional injury pathways into the tertiary phases of injury. This may allow for more effective approaches to treatment and improvement of long-term functional outcomes after HIE.

Mesenchymal Stromal Cells: Heterogeneity and Therapeutical Applications

Mesenchymal stromal cells nowadays emerge as a major player in the field of regenerative medicine and translational research. They constitute, with their derived products, the most frequently used cell type in different therapies. However, their heterogeneity, including different subpopulations, the anatomic source of isolation, and high donor-to-donor variability, constitutes a major controversial issue that affects their use in clinical applications. Furthermore, the intrinsic and extrinsic molecular mechanisms underlying their self-renewal and fate specification are still not completely elucidated. This review dissects the different heterogeneity aspects of the tissue source associated with a distinct developmental origin that need to be considered when generating homogenous products before their usage for clinical applications.