ABSTRACT: Gene expression data from teratomas formed by human iPSCs (chiPS) in SCID (Severe combined immunodeficiency) mice and humanized SCID mice (HuSCID)
Project description:Human fetal liver fibroblast were reprogrammed to chiPS without exogenous DNA integration using a single episomal vector. The chiPS were then transplanted into SCID mice and HuSCID to form teratomas. We used microarrays to profile the gene expression differences between the teratomas formed by chiPS in SCID and HuSCID mice.
Project description:Human fetal liver fibroblast were reprogrammed to chiPS without exogenous DNA integration using a single episomal vector. The chiPS were then transplanted into SCID mice and HuSCID to form teratomas. We used microarrays to profile the gene expression differences between the teratomas formed by chiPS in SCID and HuSCID mice. Pooled total RNA from two teratomas formed by chiPS in SCID and HuSCID mice respectively were used for hybridization on Affymetrix microarrays.
Project description:Bi-allelic, loss-of-function PAX1 variants underlie a syndromic form of severe combined immunodeficiency (SCID) by disrupting thymus development. To assess if bi-allelic PAX1 variants affect differentiation of thymic epithelial cells in vitro, we reprogrammed fibroblasts from a healthy control and two patients with bi-allelic pathogenic PAX1 variants to induced pluripotent stem cells (iPSCs), and subsequently differentiated these to thymic epithelial progenitor cells (TEP).
Project description:Pigs with severe combined immunodeficiency (SCID) may provide useful models for regenerative medicine, xenotransplantation, and tumor development and will aid in developing therapies for human SCID patients. Using a reporter-guided transcription activator-like effector nuclease (TALEN) system, we generated targeted modifications of recombination activating gene (RAG) 2 in somatic cells at high efficiency, including some that affected both alleles. Somatic-cell nuclear transfer performed with the mutated cells produced pigs with RAG2 mutations without integrated exogenous DNA. Biallelically modified pigs either lacked a thymus or had one that was underdeveloped. Their splenic white pulp lacked B and T cells. Under a conventional housing environment, the biallelic RAG2 mutants manifested a failure to thrive phenotype, with signs of inflammation and apoptosis in the spleen compared with age-matched wild-type animals by the time they were 4 wk of age. Pigs raised in a clean environment were healthier and, following injection of human induced pluripotent stem cells (iPSCs), quickly developed mature teratomas representing all three germ layers. The pigs also tolerated grafts of allogeneic porcine trophoblast stem cells. These SCID pigs should have a variety of uses in transplantation biology.
Project description:Pigs with severe combined immunodeficiency (SCID) may provide useful models for regenerative medicine, xenotransplantation, and tumor development and will aid in developing therapies for human SCID patients. Using a reporter-guided transcription activator-like effector nuclease (TALEN) system, we generated targeted modifications of recombination activating gene (RAG) 2 in somatic cells at high efficiency, including some that affected both alleles. Somatic-cell nuclear transfer performed with the mutated cells produced pigs with RAG2 mutations without integrated exogenous DNA. Biallelically modified pigs either lacked a thymus or had one that was underdeveloped. Their splenic white pulp lacked B and T cells. Under a conventional housing environment, the biallelic RAG2 mutants manifested a failure to thrive phenotype, with signs of inflammation and apoptosis in the spleen compared with age-matched wild-type animals by the time they were 4 wk of age. Pigs raised in a clean environment were healthier and, following injection of human induced pluripotent stem cells (iPSCs), quickly developed mature teratomas representing all three germ layers. The pigs also tolerated grafts of allogeneic porcine trophoblast stem cells. These SCID pigs should have a variety of uses in transplantation biology.
Project description:Pigs with severe combined immunodeficiency (SCID) may provide useful models for regenerative medicine, xenotransplantation, and tumor development and will aid in developing therapies for human SCID patients. Using a reporter-guided transcription activator-like effector nuclease (TALEN) system, we generated targeted modifications of recombination activating gene (RAG) 2 in somatic cells at high efficiency, including some that affected both alleles. Somatic-cell nuclear transfer performed with the mutated cells produced pigs with RAG2 mutations without integrated exogenous DNA. Biallelically modified pigs either lacked a thymus or had one that was underdeveloped. Their splenic white pulp lacked B and T cells. Under a conventional housing environment, the biallelic RAG2 mutants manifested a failure to thrive phenotype, with signs of inflammation and apoptosis in the spleen compared with age-matched wild-type animals by the time they were 4 wk of age. Pigs raised in a clean environment were healthier and, following injection of human induced pluripotent stem cells (iPSCs), quickly developed mature teratomas representing all three germ layers. The pigs also tolerated grafts of allogeneic porcine trophoblast stem cells. These SCID pigs should have a variety of uses in transplantation biology.
Project description:Severe combined immunodeficiency (SCID) occurs in various species, including humans, at a frequency as high as one per 50,000 live births. Generally, SCID can be classified according to the cause of the immunodeficiency, and it includes impaired cytokine-mediated signalling, defective V(D)J recombination, impaired pre-T-cell receptor signalling, and metabolic enzyme deficiencies. Although mice with disrupted SCID-causing genes have provided important insights into the human disease, not all the SCID mice have phenotypes that resemble those in human SCID patients. In humans, most SCID patients are reported to have impaired cytokine-mediated signalling in immune cells. IL2RG is a key component of the immune system, which is associated with the development of X-linked SCID in humans. Despite some phenotypic characterisations and functional studies being performed in SCID animals, little is known about the molecular basis of the different phenotypes of SCID in mouse and pig. In the present experiment, we generated monoallelic IL2RG (mIL2RG+/Δ69-368) KO pigs and investigated patterns of gene expression during their immune development in order to further explore our understanding of immune responses in X-linked SCID.
Project description:Severe combined immunodeficiency (SCID) occurs in various species, including humans, at a frequency as high as one per 50,000 live births. Generally, SCID can be classified according to the cause of the immunodeficiency, and it includes impaired cytokine-mediated signalling, defective V(D)J recombination, impaired pre-T-cell receptor signalling, and metabolic enzyme deficiencies. Although mice with disrupted SCID-causing genes have provided important insights into the human disease, not all the SCID mice have phenotypes that resemble those in human SCID patients. In humans, most SCID patients are reported to have impaired cytokine-mediated signalling in immune cells. IL2RG is a key component of the immune system, which is associated with the development of X-linked SCID in humans. Despite some phenotypic characterisations and functional studies being performed in SCID animals, little is known about the molecular basis of the different phenotypes of SCID in mouse and pig. In the present experiment, we generated monoallelic IL2RG (mIL2RG+/Δ69-368) KO pigs and investigated patterns of gene expression during their immune development in order to further explore our understanding of immune responses in X-linked SCID.
Project description:Severe combined immunodeficiency (SCID) occurs in various species, including humans, at a frequency as high as one per 50,000 live births. Generally, SCID can be classified according to the cause of the immunodeficiency, and it includes impaired cytokine-mediated signalling, defective V(D)J recombination, impaired pre-T-cell receptor signalling, and metabolic enzyme deficiencies. Although mice with disrupted SCID-causing genes have provided important insights into the human disease, not all the SCID mice have phenotypes that resemble those in human SCID patients. In humans, most SCID patients are reported to have impaired cytokine-mediated signalling in immune cells. IL2RG is a key component of the immune system, which is associated with the development of X-linked SCID in humans. Despite some phenotypic characterisations and functional studies being performed in SCID animals, little is known about the molecular basis of the different phenotypes of SCID in mouse and pig. In the present experiment, we generated monoallelic IL2RG (mIL2RG+/Δ69-368) KO pigs and investigated patterns of gene expression during their immune development in order to further explore our understanding of immune responses in X-linked SCID.
Project description:A source of functioning hepatocytes for liver cell transplantation and liver support is in need. hESCs , when transplanted, generally form teratomas. We studied capacity of hESCs to differentiate to hepatocyte like cells under the effect of in vivo liver regeneration. In SCID-Beige mice hepatocyte replication peaked 48 hours after CCl4 injection; 24 hours earlier 106 hESCs or EBs at different stages of differentiation were transplanted into the spleen. Comparisons were made to teratomas formed in the hind limb of untreated animals. RT-PCR and gene microarray were used for liver and human specific markers. Immunohistochemistry to AFP,AAT, ALB, HEP-PAR I AND CK-18,19 were performed. EBs formed a single large teratoma in the spleen and small teratomas in the liver. Expression of PCR- identified liver specific markers was greater in the spleen than in the liver. Adult hepatocyte specific markers were expressed in the hind limb teratoma excised after 7 weeks. When late EBs were transplanted before CCl4 exposure, no teratomas formed. Rather, an abundance of probably undifferentiated ectodermal origin cells presented. In this descriptive study, transplanted early human EBs formed teratomas that differed in size and molecular markers. Within teratomas, the degree of maturation into hepatocytes correlated better with the time duration in vivo than with growth stimulation. Late EBs formed non differentiated ectodermal cells only in a regenerative microenvironment. 4 samples were analyzed. Clean mouse liver used as neg. control. Mouse liver injected with CCl4 and transplanted with late Ebs, tumor was not observed. Two mouse livers injected with CCl4 and transplanted with late Ebs, tumor was observed.