Xenotransplantation of pig tissues has great potential to overcome the shortage of organ donors. One approach to address the vigorous immune rejection associated with xenotransplants is the use of embryonic precursor tissue, which induces and utilizes host vasculature upon its growth and development. Recently, we showed in mice that embryonic pig pancreatic tissue from embryonic day 42 (E42) exhibits optimal properties as a ␤ cell replacement therapy. We now demonstrate the proof of concept in 2 diabetic Cynomolgus monkeys, followed for 393 and 280 days, respectively. A marked reduction of exogenous insulin requirement was noted by the fourth month after transplantation, reaching complete independence from exogenous insulin during the fifth month after transplantation, with full physiological control of blood glucose levels. The porcine origin of insulin was documented by a radioimmunoassay specific for porcine C-peptide. Furthermore, the growing tissue was found to be predominantly vascularized with host blood vessels, thereby evading hyperacute or acute rejection, which could potentially be mediated by preexisting anti-pig antibodies. Durable graft protection was achieved, and most of the late complications could be attributed to the immunosuppressive protocol. While fine tuning of immune suppression, tissue dose, and implantation techniques are still required, our results demonstrate that porcine E-42 embryonic pancreatic tissue can normalize blood glucose levels in primates. Its long-term proliferative capacity, its revascularization by host endothelium, and its reduced immunogenicity, strongly suggest that this approach could offer an attractive replacement therapy for diabetes.immune-suppression ͉ rejection ͉ xeno-transplantation

Summary:Chronic granulomatous disease (CGD) is a primary immunodeficiency disorder characterized by impaired microbial killing and susceptibility to bacterial and fungal infections. Cure of the disease can be achieved by stem cell transplantation when performed early in its course, and before severe infections have developed. Invasive aspergillosis constitutes a very high risk for transplantation. We report a 4-year-old boy with Xlinked CGD who underwent successful HLA-identical peripheral blood stem cell (PBSC) transplantation during invasive pulmonary aspergillosis and osteomyelitis of the left fourth rib, which was unresponsive to antifungal treatment. During the 2 months prior to the transplant he received G-CSF-mobilized granulocyte transfusions (GTX) from unrelated donors three times a week in addition to the antifungal treatment. This resulted in clinical improvement in his respiratory status. He also received GTX during the aplastic period after the conditioning regimen, until he had engrafted. Post-transplant superoxide generation test revealed that neutrophil function was within normal range. One year post transplant the CT scan showed almost complete clearance of the pulmonary infiltrates and a marked improvement in the osteomyelitic process. Based on other reports and our own experience, GTX can serve as important treatment in patients with CGD who have failed conventional anti-fungal treatment and for whom stem cell transplantation is the only chance for cure. Bone Marrow Transplantation (2000) 26, 1025-1028.

Background Neuroblastoma (nbl) is one of the most common solid cancers in children. Prognosis in advanced nbl is still poor despite aggressive multimodality therapy. Furthermore, survivors experience severe long-term multi-organ sequelae. Hence, the identification of new therapeutic strategies is of utmost importance. Cannabinoids and their derivatives have been used for years in folk medicine and later in the field of palliative care. Recently, they were found to show pharmacologic activity in cancer, including cytostatic, apoptotic, and antiangiogenic effects.Methods We investigated, in vitro and in vivo, the anti-nbl effect of the most active compounds in Cannabis, Δ9-tetrahydrocannabinol (thc) and cannabidiol (cbd). We set out to experimentally determine the effects of those compounds on viability, invasiveness, cell cycle distribution, and programmed cell death in human nbl SK-N-SH cells.Results Both compounds have antitumourigenic activity in vitro and impeded the growth of tumour xenografts in vivo. Of the two cannabinoids tested, cbd was the more active. Treatment with cbd reduced the viability and invasiveness of treated tumour cells in vitro and induced apoptosis (as demonstrated by morphology changes, sub-G1 cell accumulation, and annexin V assay). Moreover, cbd elicited an increase in activated caspase 3 in treated cells and tumour xenografts.Conclusions Our results demonstrate the antitumourigenic action of cbd on nbl cells. Because cbd is a non psychoactive cannabinoid that appears to be devoid of side effects, our results support its exploitation as an effective anticancer drug in the management of nbl.

Our integrative model results in exposure of the majority of children with cancer to palliative care. For poor prognosis patients, palliative care is introduced early enough to allow gradual transition from symptom control after diagnosis to end of life care.

SummaryCancer stem cell (CSC) identification relies on transplantation assays of cell subpopulations sorted from fresh tumor samples. Here, we attempt to bypass limitations of abundant tumor source and predetermined immune selection by in vivo propagating patient-derived xenografts (PDX) from human malignant rhabdoid tumor (MRT), a rare and lethal pediatric neoplasm, to an advanced state in which most cells behave as CSCs. Stemness is then probed by comparative transcriptomics of serial PDXs generating a gene signature of epithelial to mesenchymal transition, invasion/motility, metastasis, and self-renewal, pinpointing putative MRT CSC markers. The relevance of these putative CSC molecules is analyzed by sorting tumorigenic fractions from early-passaged PDX according to one such molecule, deciphering expression in archived primary tumors, and testing the effects of CSC molecule inhibition on MRT growth. Using this platform, we identify ALDH1 and lysyl oxidase (LOX) as relevant targets and provide a larger framework for target and drug discovery in rare pediatric cancers.

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It has been recently shown that mutations in both of the recombination activating genes RAG1 and RAG2 are involved in each of the two different types of severe combined immunodeficiency (SCID) syndromes: T-B- SCID and Omenn's syndrome (OS). The objective of the study was to search for novel mutations in the RAG genes and to offer prenatal diagnosis for families that have been identified as at risk of T-B- SCID or OS. Mutation analyses of polymerase chain reaction products of RAG1/RAG2 genes were performed in 14 cases (T-B- SCID = 6 and OS = 8). Consanguinity was reported in seven (50%) families. Four missense mutations in the RAG2 gene in six of eight OS patients and in four of six T-B- SCID patients were detected. The C1845T transition leading to a Tre215Ile substitution is a novel mutation. All but one of the patients were homozygous for the detected mutations, possibly reflecting the consanguinity in these families and the relative rarity of the disease-causing mutations. In addition, three putative polymorphic sites were found. Prenatal diagnosis was offered to seven families, but three of them declined genetic counseling for religious reasons. In the remaining families, four pregnancies were successfully completed, and in one case, the family chose to have an abortion because of a homozygous mutation. Mutations in RAG1/RAG2 genes were detected in only some of the T-B- SCID or OS patients, and the molecular basis for the remaining cases has yet to be elucidated. Important factors such as religious beliefs need to be considered when offering prenatal diagnosis to certain families.

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