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Objective: Spontaneous pregnancies and live births are rarely reported after haematopoietic stem cell transplant (HSCT). We report spontaneous pregnancy outcomes of sexually active female survivors of childhood allogeneic HSCT, to provide more data for future counselling. Design, Patients and Measurements: Retrospective review of all female survivors of childhood haematological malignancies who had allogeneic HSCT at the Royal Children Hospital between 1985 and 2011. Data were retrieved from medical records, updated from treating haematologist or endocrinologist, and were cross‐referenced with self‐reported questionnaires. Female survivors who were sexually inactive were excluded from analysis. Results: Six of 37 (16.2%) female survivors reported spontaneous pregnancies resulting in 8 live births. Amongst 22 women who received total body irradiation (n = 21) ± cranial irradiation or isolated cranial irradiation (n = 1), and high‐dose cyclophosphamide, three reported pregnancy resulting in live births (14%), whilst three of 15 women who received chemotherapy alone had pregnancy with live births (20%). Conclusions: Our current finding, albeit a small sample size, reinforces the importance of counselling female survivors of HSCT about the possibility of spontaneous pregnancy occurring despite documented ovarian failure and for need of contraception to avoid unplanned pregnancy. [ABSTRACT FROM AUTHOR]

Abstract: Astroglial cells in teleost fish occur mostly as radial glia. We established a culture system derived from brain tissue of mature cichlid fish Astatotilapia burtoni to study fish astroglial cells in more detail. Cells were passaged several times to expand the cultures, and could be kept in vitro for several months. The cell identity was tested by the presence of glial fibrillary acidic protein (GFAP); in addition, cells expressed the tight junction adaptor protein zonula occludens-1 (ZO-1) known to be present on astroglial cells in fish brain. This is consistent with the radial and epithelial nature of fish astroglial cells derived from neuroepithelium. To characterize the properties of cultured astroglial cells we challenged them in hypo-osmotic conditions. Cells reacted with volume increase, slower but similar to mammalian astrocytes. We also tested whether astroglial cells support growth during axonal elongation. We placed retinal explants on astroglial cultures and found neurites extending readily on these cells, compared to controls which showed no or little growth. Thus, we established a culture system for astroglial cells from the mature fish brain that demonstrates their neuroepithelial properties. This culture system will be useful to study functions in which glial cells are thought to play an important role: e.g. regulation of water homeostasis and supporting axonal regeneration. [Copyright &y& Elsevier]

Human herpesvirus 6 (HHV6) is the major cause of posttransplant acute limbic encephalitis (PALE) in immunosuppressed patients following hematopoietic stem cell transplant. Memory impairment and temporal lobe epilepsy following PALE are reported in adults, but sequelae in young children are unknown. We report three children with HHV6-associated PALE 20-23 days after cord blood transplantation for leukemias who developed symptomatic generalized epilepsy. Patients were followed for 2-8 years and underwent magnetic resonance imaging (MRI) and video-electroencephalography (EEG). Two patients underwent viral and autoimmune testing and immunotherapies. Generalized seizures, including tonic seizures, developed 11-18 months after HHV6-associated PALE. Seizures were frequent and resistant to multiple antiepileptic drugs (AEDs). Generalized slow spike-wave and low-voltage fast activity were recorded on interictal and ictal EEGs. The two younger patients regressed in their general abilities, synchronous with seizure evolution, whereas the older patient developed a severe amnestic syndrome that halted intellectual development. Serial MRI studies revealed bilateral signal change and atrophy in the medial temporal structures of all patients. In the two investigated patients, there was no evidence of chronic HHV6 infection, minimal evidence of cerebral inflammation, and no significant improvement with pulse with intravenous methylprednisolone and immunoglobulin. The severe and generalized seizure, cognitive, and EEG sequelae of HHV6-related PALE in these children may be due to a chronic, viral, or immune-mediated inflammatory process or developmental epileptogenesis resulting from bilateral hippocampal injury at an early age, although there was a paucity of evidence for either. [ABSTRACT FROM AUTHOR]

Abstract: In the retina of teleost fish, new ganglion cells are generated from a circumferential peripheral growth zone at the edge of the eye throughout life. Addressing the question how new cells are fitted into the existing retina, we investigated newly formed ganglion cells in the zebrafish retina morphologically, by tracing them from the cut optic nerve with rhodamine dextran. We identified proliferating cells by antibody detection against proliferating cell nuclear antigen. In addition, newly formed bipolar cell and amacrine cell dendrites were investigated by antibodies against protein kinase C (PKC) and choline-acetyl-transferase (ChaT), respectively, and analyzed in sections or wholemount preparations using confocal microscopy. In retinal sections we observed that ganglion cell dendritic branches in the inner plexiform layer were in close apposition to dividing cells. In the periphery of retinal wholemounts, we detected rhodamine traced ganglion cells adjacent to the growth zone, extending dendrites in proximity to the growth zone, typically branching off in opposite directions running parallel to the retinal rim over more then 100 μm. Ganglion cells with similar dendritic branching patterns were not found in more central retinal areas. Similarly, the dendrites of ChaT-positive amacrine cells showed a preference for running parallel to the circumference in the periphery. Dendritic branches of PKC-positive bipolar cells did not show similar preferred orientation. The change in shape of the dendritic tree with distance from the periphery was studied for the Ma type ganglion cell. The data are consistent with the idea that existing ganglion cells might control differentiation of new ganglion cells. Moreover, ganglion cells with specific branching patterns towards the retinal periphery undergo a restructuring of their dendritic trees. [Copyright &y& Elsevier]

Umbilical cord blood cells have therapeutic potential for neurological disorders, through a paracrine mechanism of action. A greater understanding of the safety and immunological effects of allogeneic donor cord blood cells in the context of a healthy recipient immune system, such as in cerebral palsy, is needed. This study aimed to determine how quickly donor cord blood cells were cleared from the circulation in children with cerebral palsy who received a single intravenous infusion of 12/12 human leucocyte antigen (HLA)-matched sibling cord blood cells. Twelve participants with cerebral palsy aged 2–12 years received cord blood cell infusions as part of a phase I trial of umbilical blood infusion for cerebral palsy. Digital droplet PCR analysis of DNA copy number variants specific to donor and recipient was used to assess donor DNA clearance at five timepoints post-infusion, a surrogate measure of cell clearance. Donor cells were cleared by 3 months post-infusion in 11/12 participants. When detected, donor DNA was at a fraction of 0.01–0.31% of total DNA with no signs of graft-versus-host disease in any participant. The donor DNA clearance times provided by this study have important implications for understanding the safety of allogeneic cord blood cell infusion for cerebral palsy and translational tissue engineering or regenerative medicine research in other disorders. [ABSTRACT FROM AUTHOR]

A minor viral population of oseltamivir-resistant A( H3 N2) viruses ( E119 V neuraminidase mutation) was selected and maintained in a continually infected immunocompromised child following initial oseltamivir treatment. A subsequent course of oseltamivir given 7 weeks later rapidly selected for the E119 V variant resulting in a near-pure population of the resistant virus. The study highlights the challenges of oseltamivir treatment of immunocompromised patients that are continually shedding virus and demonstrates the ability of the E119 V oseltamivir-resistant virus to be maintained for prolonged periods even in the absence of drug-selective pressure. [ABSTRACT FROM AUTHOR]

Abstract: We performed a retrospective analysis on the outcomes of 135 hematopoietic stem cell transplantations (HSCTs) for primary immunodeficiency disorders in Australian and New Zealand Children’s Haematology Oncology Group transplantation centers between 1992 and 2008. The most common indications for HSCT were severe combined immunodeficiency, Wiskott-Aldrich syndrome, and chronic granulomatous disease. Five-year overall survival (OS) was 72% for the entire cohort. Disease-specific 5-year OS was 70% for severe combined immunodeficiency, 81% for Wiskott-Aldrich syndrome, and 69% for chronic granulomatous disease. Transplantation-related mortality (TRM) was 10% at day +100. TRM and OS were equivalent in recipients of related and unrelated donor transplants. Source of stem cells had no impact on TRM or OS with outcomes following unrelated umbilical cord blood similar to unrelated bone marrow. The presence of interstitial pneumonitis, active cytomegalovirus infection, or veno-occlusive disease were all independent variables that significantly decreased OS. This large series supports the use of HSCT as curative therapy for a range of primary immunodeficiency disorders, demonstrating excellent survival after both related and unrelated donor transplantation. [Copyright &y& Elsevier]

We compared outcomes after 94 HLA-matched sibling, 168 unrelated donor bone marrow (BM; n = 81 matched and n = 88 mismatched), and 86 cord blood transplantations in patients age 1 to 15 years with acute lymphoblastic leukemia (ALL) in second complete remission (CR). All patients had their first BM relapse within 3 years from diagnosis. Cox regression models were constructed to examine for differences in transplant outcome by donor source. Risks of grade 2 to 4 acute graft-versus-host disease (aGVHD) and chronic graft-versus-host disease (cGVHD), when compared to HLA-matched sibling transplants, were higher after matched unrelated donor BM (relative risk [RR], 2.42; P = .001; RR, 5.12; P < .001, respectively), mismatched BM (RR, 3.24; P < .001; RR, 5.19; P < .001, respectively), and cord blood (RR, 2.67; P < .001; RR, 2.54; P = .024, respectively) transplants. Although nonrelapse mortality was higher after transplantation of mismatched unrelated donor BM and cord blood, there were no differences in leukemia-free survival (LFS) between HLA-matched sibling and any of the unrelated donor transplantations. The 3-year probabilities of LFS were 50% after HLA-matched sibling and 44% after matched unrelated BM, and 44% after mismatched unrelated BM and 43% after cord blood transplantation. Our observations support transplantation of BM or cord blood from a suitably matched unrelated donor or cord blood for patients without an HLA-matched sibling with ALL in second CR. [ABSTRACT FROM AUTHOR]

: ObjectiveOptimizing cord blood donor selection based mainly on cell dose and human leukocyte antigen (HLA) disparities may further improve results of unrelated cord blood transplants (UCBT).: Materials and resultsWe analyzed 550 UCBTs for hematologic malignancies reported to the Eurocord Registry. Main outcomes and prognostic factors were analyzed in univariable and multivariable analyses incorporating center and period effects and using death and relapse as competitive risks for nonfatal endpoints. Nucleated cell (NC) dose before freezing and number of HLA disparities had a significant influence on outcome. Cumulative incidence (CI) of neutrophil and platelet recovery was associated with the number of HLA mismatches, number of NC before freezing, and use of granulocyte colony-stimulating factor. Coexistence of HLA class I and II disparities and high CD34 cell dose in the graft were associated with graft-vs-host disease grades III–IV. CI of disease relapse was higher in matched transplants showing a graft-vs-leukemia effect increased in HLA-mismatched transplants. Overall 3-year survival was 34.4%. Prognostic factors for survival were recipient age, gender, and disease status.: ConclusionOur results provide indications for a better choice of cord blood units according to cord blood cell content and HLA. [Copyright &y& Elsevier]

In this study, two amino acid substitutions, Arg260His and Val414Phe, have been identified in the factor XIIIA subunits of factor XIII deficient patients of Syrian and Indian descent, respectively. To confirm the deleterious effects of these substitutions, both variant sequences have been engineered into cDNA clones and the mutant enzymes expressed in yeast. Determination of the transglutaminase activity and immuno detection of the mutant enzymes together with mRNA hybridization revealed that the mutations dramatically reduce both the catalytic activity and the level of enzyme expressed in yeast. The mutations Arg260His and Val414Phe occur within the ‘core’ domain of the enzyme. Computer modelling of the mutant enzymes reveals that the substitution of the Arg260 by His results in the loss of a conserved electrostatic interaction whereas the effect of the Val414Phe substitution is a consequence of the large increase in side-chain volume. Although both mutations do not effect the active site directly, they are predicted to reduce the stability of the enzyme. The effects of these two amino acid substitutions on enzyme expression and three-dimensional structure strongly confirm that residues which are located outside of the active site can have a significant effect on protein stability and function. [ABSTRACT FROM AUTHOR]