Stem cells and the frontiers of neonatology

Maternal and fetal safety outcomes after in utero stem cell injection: A systematic review

OBJECTIVE

To investigate the maternal and fetal safety of In utero stem cell transplantation (IUSCT).

METHODS

Medline®, Embase and Cochrane library (1967-2023) search for publications reporting IUSCT in humans. Two reviewers independently screened abstracts and full-text papers.

RESULTS

Sixty six transplantation procedures in 52 fetuses were performed for haemoglobinopathies (n = 14), red cell/bleeding disorders (n = 4), immunodeficiencies (n = 15), storage disorders (n = 7), osteogenesis imperfecta (n = 2) and healthy fetuses (n = 10). The average gestational age was 18.9 weeks; of procedures reporting the injection route, cells were delivered by intraperitoneal (n = 37), intravenous (n = 19), or intracardiac (n = 4) injection or a combination (n = 3); most fetuses received one injection (n = 41). Haematopoietic (n = 40) or mesenchymal (n = 12) stem cells were delivered. The cell dose was inconsistently reported (range 1.8-3.3 × 109 cells total (n = 27); 2.7-5.0 × 109 /kg estimated fetal weight (n = 17)). The acute fetal procedural complication rate was 4.5% (3/66); the acute fetal mortality rate was 3.0% (2/66). Neonatal survival was 69.2% (36/52). Immediate maternal and pregnancy outcomes were reported in only 30.8% (16/52) and 44.2% (23/52) of cases respectively. Four fetal/pregnancy outcomes would also classify as ≥ Grade 2 maternal adverse events.

CONCLUSIONS

Short-, medium-, and long-term maternal and fetal adverse events should be reported in all IUSCT studies.

Cord and peripheral blood erythrocyte analysis by scanning electron microscopy and flow cytometry

INTRODUCTION

Human umbilical cord blood is rich in hematopoietic cells. We aimed to focus on the morphological, biochemical, membrane protein profile and surface protein expression differences of erythrocytes, isolated from cord and adult peripheral blood using techniques such as high-resolution scanning electron microscopy (SEM), gel electrophoresis (SDS-PAGE) and flow cytometry.

METHODS

Adult peripheral blood was collected from consenting adults, and umbilical cord blood was procured from consenting mothers, post-delivery at Medical College, Kolkata. We emphasized on cord and adult peripheral blood erythrocytes' morphological variations using SEM images and protein expression by flow cytometric analysis. Some conventional biochemical analyses such as osmotic fragility of the cell membrane, haemoglobin co-oxidation study and lipid peroxidation assay were done for supporting evidence along with membrane protein content using gel electrophoresis.

RESULTS

Our SEM images indicated clear morphological variations in cord erythrocyte with a higher degree of cellular deformities and difference in membrane texture. Flow cytometric analysis of cord erythrocyte showed a significant difference in CD235a expression than adults. We observed an overexpression of GLUT1 and decreased expression of Band 3 in cord erythrocyte membrane. Our results also showed cord erythrocytes have low osmotic fragility, a slower rate of co-oxidation of cord haemoglobin and a lesser lipid peroxidation level than that of adults.

CONCLUSION

Cord blood erythrocytes have deeper indentations leading to higher flexibility, more oxygen-carrying capacity and less osmotic fragility in comparison with adult erythrocytes. The expression of CD235a and Band 4.5 (GLUT 1) was significantly higher in cord erythrocytes than peripheral adult erythrocytes.

Fetal stem cell transplantation and gene therapy

The present chapter summarizes our current knowledge on fetal stem cell and gene therapy. It focuses on these therapeutic alternatives in regard to past experiences and ongoing and planned studies in humans. Several methodological challenges are discussed that may have wide implications on how these methods could be introduced in clinical practices. Although still promising, the methods are afflicted with very special requirements not least in regard to safety and ethical questions. Furthermore, careful monitoring and extended follow-up of the child and his/hers mother who receive prenatal stem cell or gene treatments are of outmost importance. Taken these prerequisites into consideration, it is natural that this type of experimental fetal therapies requires collaboration between different disciplinaries and institutions within medicine.

The transplantation of Akt-overexpressing amniotic fluid-derived mesenchymal stem cells protects the heart against ischemia-reperfusion injury in rabbits

Amniotic fluid-derived mesenchymal stem cells (AFMSCs) are an attractive cell source for applications in regenerative medicine, due to characteristics such as proliferative capacity and multipotency. In addition, Akt, a serine‑threonine kinase, maintains stem cells by promoting viability and proliferation. Whether the transplantation of Akt-overexpressing AFMSCs protects the heart against ischemia‑reperfusion (I/R) injury has yet to be elucidated. Accordingly, the Akt gene was overexpressed in AFMSCs using lentiviral transduction, and Akt‑AFMSCs were transplanted into the ischemic myocardium of rabbits prior to reperfusion. Any protective effects resulting from this procedure were subsequently sought after three weeks later. A histological examination revealed that there was a decrease in intramyocardial inflammation and ultrastructural damage, and an increase in capillary density and in the levels of GATA binding protein 4, connexin 43 and cardiac troponin T in the Akt‑AFMSC group compared with the control group. A significant decrease in cardiomyocyte apoptosis, accompanying an increase in phosphorylated Akt and B‑cell lymphoma 2 (Bcl-2) and a decrease in caspase‑3, was also observed. Furthermore, the left ventricular function was markedly augmented in the Akt‑AFMSC group compared with the control group. These observations suggested that the protective effect of AFMSCs may be due to the delivery of secreted cytokines, promotion of neoangiogenesis, prevention of cardiomyocyte apoptosis, transdifferentiation into cardiomyocytes and promotion of the viability of AFMSCs, which are assisted by Akt gene modification. Taken together, the results of the present study have indicated that transplantation of Akt-AFMSCs is able to alleviate myocardial I/R injury and improve cardiac function.

A potential platform for developing 3D tubular scaffolds for paediatric organ development

Children suffer from damaged or loss of hollow organs i.e. trachea, oesophagus or arteries from birth defects or diseases. Generally these organs possess an outer matrix consisting of collagen, elastin, and cells such as smooth muscle cells (SMC) and a luminal layer consisting of endothelial or epithelial cells, whilst presenting a barrier to luminal content. Tissue engineering research enables the construction of such organs and this study explores this possibility with a bioabsorbable nanocomposite biomaterial, polyhedral oligomeric silsesquioxane poly(ε-caprolactone) urea urethane (POSS-PCL).Our established methods of tubular graft extrusion were modified using a porogen-incorporated POSS-PCL and a new lamination method was explored. Porogen (40, 60 or 105 µm) were introduced to POSS-PCL, which were fabricated into a bilayered, dual topography matching the exterior and luminal interior of tubular organs. POSS-PCL with different amounts of porogen were tested for their suitability as a SMC layer by measuring optimal interactions with human adipose derived stem cells. Angiogenesis potential was tested with the chorioallantoic membrane assay. Tensile strength and burst pressures of bilayared tubular grafts were determined. Scaffolds made with 40 µm porogen demonstrated optimal adipose derived stem cell integration and the scaffolds were able to accommodate angiogenesis. Mechanical properties of the grafts confirmed their potential to match the relevant physiological and biophysical parameters. This study presents a platform for the development of hollow organs for transplantation based on POSS-PCL. These bilayered-tubular structures can be tailor-made for cellular integration and match physico-mechanical properties of physiological systems of interest. More specific luminal cell integration and sources of SMC for the external layer could be further explored.

Fetal mesenchymal stromal cells from cryopreserved human chorionic villi: cytogenetic and molecular analysis of genome stability in long-term cultures

BACKGROUND AIMS

First-trimester chorionic villi (CV) are an attractive source of human mesenchymal stromal cells (hMSC) for possible applications in cellular therapy and regenerative medicine. Human MSC from CV were monitored for genetic stability in long-term cultures.

METHODS

We set up a good manufacturing practice cryopreservation procedure for small amounts of native CV samples. After isolation, hMSC were in vitro cultured and analyzed for biological end points. Genome stability at different passages of expansion was explored by karyotype, genome-wide array-comparative genomic hybridization and microsatellite genotyping.

RESULTS

Growth curve analysis revealed a high proliferative potential of CV-derived cells. Immunophenotyping showed expression of typical MSC markers and absence of hematopoietic markers. Analysis of multilineage potential demonstrated efficient differentiation into adipocytes, osteocytes, chondrocytes and induction of neuro-glial commitment. In angiogenic experiments, differentiation in endothelial cells was detected by in vitro Matrigel assay after vascular endothelial growth factor stimulation. Data obtained from karyotyping, array-comparative genomic hybridization and microsatellite genotyping comparing early with late DNA passages did not show any genomic variation at least up to passage 10. Aneuploid clones appeared in four of 14 cases at latest passages, immediately before culture growth arrest.

CONCLUSIONS

Our findings indicate that hCV-MSC are genetically stable in long-term cultures at least up to passage 10 and that it is possible to achieve clinically relevant amounts of hCV-MSC even after few stages of expansion. Genome abnormalities at higher passages can occasionally occur and are always associated with spontaneous growth arrest. Under these circumstances, hCV-MSC could be suitable for therapeutic purposes.

Engraftment of genetically modified human amniotic fluid-derived progenitor cells to produce coagulation factor IX after in utero transplantation in mice

Human amniotic fluid derived progenitor cells (hAFPCs) may be multipotent and can be considered a potential tool in the field of cell therapy for haemophilia B. Their capacity to express human coagulation factor IX (hFIX) after transduction and their fate after in utero transplantation is unknown. hAFPCs isolated from second trimester pregnancies were assessed for their phenotypic markers, multilineage capacity, and expression of hFIX after transduction. Their engraftment potential was analysed in a mouse model after in utero transplantation at embryonic day 12.5. Immunohistochemistry, fluorescence in situ, ELISA and PCR were used to assess post-transplant chimeras. hAFPCs expressed several pluripotent markers, including NANOG, SOX2, SSEA4 and TRA-1-60, and could differentiate into adipocytes and osteocytes. In vitro, after transduction with hFIX and EGFP cDNAs, constitutive hFIX protein expression and clotting activity were found. Engraftment was achieved in various foetal tissues after in utero transplantation. Safe engraftment without oncogenesis was confirmed, with low donor cell levels, but persistent engraftment, into different organs (liver, heart and lung) through to 12 weeks of age. Transgenic expression of circulating hFIX was detected in recipient mice for up to 12 weeks. hAFPCs can be engrafted long-term in immunocompetent mice after in utero transplantation. Thus, cell transplantation approaches using genetically engineered hAFPCs may prove valuable for the prenatal treatment for haemophilia B.

Therapeutic effect of transplantation of human amniotic membrane- and umbilical cord-derived mesenchymal stem cells on hepatic cirrhosis in rats

AIM: To evaluate the therapeutic effect of transplantation of human amniotic membrane-derived mesenchymal stem cells (hAM-MSCs) and human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on carbon tetrachloride (CCl₄)-induced hepatic cirrhosis in rats.

METHODS: hAM-MSCs and hUC-MSCs were isolated and analyzed by flow cytometry for detection of expression of CD44, CD29 and CD34. Hepatic cirrhosis was induced in rats with CCl₄. At week 8, five rats were killed to conduct pathological examination to confirm successful induction of hepatic cirrhosis, and 30 rats with hepatic cirrhosis were randomly and equally divided into three groups: hAM-MSCs group, hUC-MSCs group and control group. The hAM-MSCs and hUC-MSCs groups were infused wit 2×10⁶ MSCs in 2 mL of saline via the tail vein, while the control group was given equal volume of saline. Liver function was examined before cell transplantation and 4 wk after cell transplantation. HE staining and Masson dyeing were performed to observe pathological changes in the liver. The expression of alpha-smooth muscle actin (α-SMA) in the liver was determined by immunohistochemistry.

RESULTS: Both isolated hAM-MSCs and hUC-MSCs expressed CD29 and CD44, but did not express CD34. After cell transplantation, liver function parameters were markedly improved (all P < 0.05) and the expression of α-SMA was reduced in the hAM-MSCs and hUC-MSCs groups compared to the control group (130.6 ± 3.0, 127.0 ± 2.6 vs 152.2 ± 5.4, both P < 0.05). There were no statistically significant differences in liver function parameters and α-SMA expression between the hAM-MSCs and hUC-MSCs groups.

CONCLUSION: Transplantation of hAM-MSCs and hUC-MSCs could efficiently improve liver functions and inhibit liver fibrosis in rats.

Developing treatment options for metachromatic leukodystrophy

Metachromatic leukodystrophy (MLD) represents a devastating lysosomal storage disease characterized by intralysosomal accumulation of the sphingolipid sulfatide in various tissues. Three types of the disease are currently distinguished: the late-infantile, which is the most commonly observed, the juvenile and the adult type. Demyelination represents the main histopathological feature of the disorder, leading to neurological impairment with no curative treatment currently available. Nevertheless, the increased scientific interest on the disease has led to the experimental use of innovative therapeutic approaches in animal models, aiming to provide an effective therapeutic regimen for human patients, as well. This paper provides an overview of developing treatment options among patients with MLD. Apart from hematopoietic stem cell transplantation, already in use for decades, other recent data discussed includes umbilical cord blood and stem cell transplantation, enzyme replacement therapy, gene therapy and autologous hematopoietic transplantation of genetically modified stem cells. Gene therapy with oligodedroglial, neural progenitor, embryonic and microencapsulated recombinant cells represents add-on treatment options still on experimental level.

Complete blood count reference values of cord blood in Taiwan and the influence of gender and delivery route on them

BACKGROUND

Cord blood banking has become more popular in recent years. Checking cord blood complete blood count (CBC) and white blood cell (WBC) differential counts (DCs) is essential before cryopreserving the cord blood units. Therefore, establishing the normal reference values of cord blood CBC and WBC DC is important in clinical practice and research.

OBJECTIVES

To obtain a large-scale population-based normal CBC and WBC DC reference values of healthy neonates' cord blood from a public cord blood bank and to investigate the influence of the gender and delivery route.

METHODS

From September 2001 to November 2006, the cord blood of healthy Taiwanese neonates with gestational age 36 weeks and more were collected by Tzu Chi Cord Blood Bank with written informed consents. All cord blood samples were analyzed by Sysmex XE2100 automated hematology analyzer (Sysmex Corporation, Kobe, Japan) to obtain the CBC. The WBC DC was calculated by manual method. We used Student's t test and Mann-Whitney U test for investigating the influences of gender and delivery route on the CBC and WBC DC reference values. The results were presented by mean±standard deviation or 2.5-97.5th percentiles.

RESULTS

In the study period, totally 5602 cord blood samples were collected eligibly for analysis. The cord blood CBC and WBC DC normal reference values were calculated. The female neonates had significantly higher mean corpuscular volume, platelet count, and WBC count, but lower red blood cell (RBC) count, hemoglobin (Hb), hematocrit, and mean corpuscular Hb concentration values (p<0.001). Newborns through vaginal delivery had significantly higher RBC count, Hb, hematocrit, platelet count, and WBC count (p<0.001). The percentages of some different types WBC were significantly influenced by gender and delivery routes. Male babies had higher lymphocyte, monocyte, eosinophil, basophil, and nucleated RBC ratios than the female neonates. Newborns through cesarean section had significantly lower neutrophil, monocyte, and nucleated RBC ratios, but higher lymphocyte and eosinophil ratios, than newborns through vaginal delivery.

CONCLUSION

We successfully obtained the normal CBC and WBC DC reference values of the cord blood in Taiwan. Gender and delivery routes were important confounding factors that influenced the cord blood CBC and WBC DC values.