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David H. Sachs - One of the best experts on this subject based on the ideXlab platform.
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Development of transplantable B-cell lymphomas in the MHC-defined Miniature Swine model.
Cancer cell international, 2019Co-Authors: Alec R. Andrews, David H. Sachs, Zhaohui Wang, Robert A. Wilkinson, Jay A. Fishman, Nalu Navarro-alvarez, Christene A. HuangAbstract:Establishment of transplantable tumors in clinically relevant large animals allows translational studies of novel cancer therapeutics. Here we describe the establishment, characterization, and serial transplantation of a naturally occurring B-cell lymphoma derived from a unique, highly inbred sub-line of Massachusetts General Hospital (MGH) major histocompatibility complex (MHC)-defined Miniature Swine. The lymphoblastic cell line (LCL) originated from peripheral blood of a 2.5 year old female Swine leukocyte antigen (SLA)dd-inbred Miniature Swine breeder demonstrating clinical signs of malignancy. Flow cytometric phenotypic analysis of subclones derived from the original cell line revealed surface markers commonly expressed in a B-cell lineage neoplasm. A subclone of the original LCL was transplanted into mildly-conditioned histocompatible Miniature Swine and immunocompromised NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice. Tissue and blood samples harvested 2 weeks following subcutaneous and intravenous injection in a highly inbred SLAdd pig were cultured for tumor growth and phenotypic analysis before serial transfer into NSG mice. Evidence of tumor growth in vivo was found in all tumor cell recipients. In vitro growth characteristics and surface phenotype were comparable between the original and serially transplanted tumor cell lines. These results indicate the feasibility of developing a large-animal transplantable tumor model using cells derived from spontaneously occurring hematologic malignancies within the highly inbred Miniature Swine herd.
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Miniature Swine as a Clinically Relevant Model of Graft-Versus-Host Disease.
Comparative medicine, 2015Co-Authors: Raimon Duran-struuck, David H. Sachs, Christene A. Huang, Katherine Orf, Roderick T. Bronson, Thomas R. SpitzerAbstract:Miniature Swine provide a preclinical model of hematopoietic cell transplantation (HCT) for studies of graft-versus-host disease. HCT between MHC-matched or -mismatched pigs can be performed to mimic clinical scenarios with outcomes that closely resemble those observed in human HCT recipients. With myeloablative conditioning, HCT across MHC barriers is typically fatal, with pigs developing severe (grade III or IV) GVHD involving the gastrointestinal tract, liver, and skin. Unlike rodent models, Miniature Swine provide an opportunity to perform extended longitudinal studies on individual animals, because multiple tissue biopsies can be harvested without the need for euthanasia. In addition, we have developed a Swine GVHD scoring system that parallels that used in the human clinical setting. Given the similarities of GVHD in pigs and humans, we hope that the use of this scoring system facilitates clinical and scientific discourse between the laboratory and the clinic. We anticipate that results of Swine studies will support the development of new strategies to improve the identification and treatment of GVHD in clinical HCT scenarios.
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the induction of tolerance of renal allografts by adoptive transfer in Miniature Swine
American Journal of Transplantation, 2013Co-Authors: Masayoshi Okumi, Vincenzo Villani, Beatrice Gillon, Masayuki Tasaki, Atsushi Hirakata, Joseph R Scalea, Taylor Cormack, David H. Sachs, Akira Shimizu, Kazuhiko YamadaAbstract:Our previous in vitro data have demonstrated that regulatory mechanisms are involved in tolerance of class I-mismatched renal allografts in Miniature Swine treated with 12 days of high dose Cyclsporin A. In this study, we attempted to induce tolerance of class I-mismatched kidneys by adoptive transfer of cells and/or kidneys from long-term tolerant animals. Fifteen SLA dd Miniature Swine received 1.5 Gy whole body irradiation and class I-mismatched (SLA gg ) kid
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Genotyping of Porcine Endogenous Retroviruses from a Family of Miniature Swine
Journal of virology, 2004Co-Authors: Gary Quinn, David H. Sachs, James Wood, Kristen M. Suling, Scott Arn, Henk-jan Schuurman, Clive PatienceAbstract:The identification of animals in an inbred Miniature Swine herd that consistently fail to produce replication- competent humantropic porcine endogenous retrovirus (PERV) has prompted studies on the biology of PERV in transmitter and nontransmitter animals. We analyzed PERV RNA transcript profiles in a family of inbred Miniature Swine (SLAd/d haplotype) in which individual members differed in their capacity to generate humantropic and ecotropic (i.e., pigtropic) virus. We identified unique HaeIII and HpaII gag restriction fragment length polymorphism (RFLP) profiles resulting from single nucleotide polymorphisms in blood cells; these were found only in animals that produced humantropic PERV. These HaeIII and HpaII gag RFLP profiles proved to be components of humantropic PERV as they were transmitted to 293 human target cells in vitro. The humantropic HaeIII and HpaII gag RFLP genotypes in the family of study were not present in other Miniature Swine in the herd that produced humantropic PERV, indicating that these RFLP profiles relate specifically to this family's lineage.
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spleen transplantation in Miniature Swine surgical technique and results in major histocompatibility complex matched donor and recipient pairs
Transplantation, 2003Co-Authors: Bernd Gollackner, David H. Sachs, Christene A. Huang, Stuart L. Houser, Michael Duggan, F J M F Dor, C Knosalla, L Buhler, Tatsuo Kawai, David K C CooperAbstract:Spleen transplantation (Tx) between some strains of rodents can lead to donor-specific tolerance either spontaneously or after a short course of immunosuppression. This study developed a surgical technique for spleen Tx in Miniature Swine to investigate its immunologic impact in a large animal model.
Christene A. Huang - One of the best experts on this subject based on the ideXlab platform.
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Development of transplantable B-cell lymphomas in the MHC-defined Miniature Swine model.
Cancer cell international, 2019Co-Authors: Alec R. Andrews, David H. Sachs, Zhaohui Wang, Robert A. Wilkinson, Jay A. Fishman, Nalu Navarro-alvarez, Christene A. HuangAbstract:Establishment of transplantable tumors in clinically relevant large animals allows translational studies of novel cancer therapeutics. Here we describe the establishment, characterization, and serial transplantation of a naturally occurring B-cell lymphoma derived from a unique, highly inbred sub-line of Massachusetts General Hospital (MGH) major histocompatibility complex (MHC)-defined Miniature Swine. The lymphoblastic cell line (LCL) originated from peripheral blood of a 2.5 year old female Swine leukocyte antigen (SLA)dd-inbred Miniature Swine breeder demonstrating clinical signs of malignancy. Flow cytometric phenotypic analysis of subclones derived from the original cell line revealed surface markers commonly expressed in a B-cell lineage neoplasm. A subclone of the original LCL was transplanted into mildly-conditioned histocompatible Miniature Swine and immunocompromised NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice. Tissue and blood samples harvested 2 weeks following subcutaneous and intravenous injection in a highly inbred SLAdd pig were cultured for tumor growth and phenotypic analysis before serial transfer into NSG mice. Evidence of tumor growth in vivo was found in all tumor cell recipients. In vitro growth characteristics and surface phenotype were comparable between the original and serially transplanted tumor cell lines. These results indicate the feasibility of developing a large-animal transplantable tumor model using cells derived from spontaneously occurring hematologic malignancies within the highly inbred Miniature Swine herd.
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Miniature Swine as a Clinically Relevant Model of Graft-Versus-Host Disease.
Comparative medicine, 2015Co-Authors: Raimon Duran-struuck, David H. Sachs, Christene A. Huang, Katherine Orf, Roderick T. Bronson, Thomas R. SpitzerAbstract:Miniature Swine provide a preclinical model of hematopoietic cell transplantation (HCT) for studies of graft-versus-host disease. HCT between MHC-matched or -mismatched pigs can be performed to mimic clinical scenarios with outcomes that closely resemble those observed in human HCT recipients. With myeloablative conditioning, HCT across MHC barriers is typically fatal, with pigs developing severe (grade III or IV) GVHD involving the gastrointestinal tract, liver, and skin. Unlike rodent models, Miniature Swine provide an opportunity to perform extended longitudinal studies on individual animals, because multiple tissue biopsies can be harvested without the need for euthanasia. In addition, we have developed a Swine GVHD scoring system that parallels that used in the human clinical setting. Given the similarities of GVHD in pigs and humans, we hope that the use of this scoring system facilitates clinical and scientific discourse between the laboratory and the clinic. We anticipate that results of Swine studies will support the development of new strategies to improve the identification and treatment of GVHD in clinical HCT scenarios.
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spleen transplantation in Miniature Swine surgical technique and results in major histocompatibility complex matched donor and recipient pairs
Transplantation, 2003Co-Authors: Bernd Gollackner, David H. Sachs, Christene A. Huang, Stuart L. Houser, Michael Duggan, F J M F Dor, C Knosalla, L Buhler, Tatsuo Kawai, David K C CooperAbstract:Spleen transplantation (Tx) between some strains of rodents can lead to donor-specific tolerance either spontaneously or after a short course of immunosuppression. This study developed a surgical technique for spleen Tx in Miniature Swine to investigate its immunologic impact in a large animal model.
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Peripheral regulation of graft-versus-host alloreactivity in mixed chimeric Miniature Swine.
Transplantation, 2001Co-Authors: Shaun M. Kunisaki, Christene A. Huang, Gary W. Haller, Yasushi Fuchimoto, David H. SachsAbstract:Background. Despite the presence of circulating donor-derived T cells during the induction of mixed chimerism across MHC barriers in Miniature Swine, severe graft-versus-host disease was avoided in the majority of animals. In this study, we investigated the possible roles of recipient and donor lymphoid populations in the regulation of donor-anti-recipient alloreactivity. Methods. Mixed chimerism across a full MHC-mismatch barrier was established in Miniature Swine using a high-dose allogeneic peripheral blood stem cell protocol. Peripheral blood mononuclear cells from mixed chimeric Swine were co-cultured with naive donor-matched responders and naive recipient-matched stimulators in mixed lymphocyte reactions. Results. Peripheral blood mononuclear cells from mixed chimeras inhibited donor-anti-recipient proliferation. This suppression was radioresistant to 25 Gy. Suppression of donor-anti-recipient alloreactivity was not observed in mixed lymphocyte co-cultures when donor-derived cells were added in the absence of recipient-derived cells. Conclusions. These results suggest an association between the presence of an active and relatively radioresistant cell population, demonstrable in vitro, and the regulation of graft-versus-host disease across MHC barriers in mixed chimeric Miniature Swine.
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skin specific alloantigens in Miniature Swine
Transplantation, 2001Co-Authors: Yasushi Fuchimoto, Kwabena Mawulawde, Joren C. Madsen, Christene A. Huang, Margaret L Schwarze, Matthew T Menard, Zachary L Gleit, Hiroshi Kitamura, David H. SachsAbstract:Background. The acceptance of skin allografts has historically been among the most challenging problems in the field of transplantation, attributed, at least in part, to the existence of antigens expressed by skin but not by other tissues. Many studies have suggested the existence of skin-specific antigens in rodents, but data in large-animal models are more limited. Methods. We have recently developed protocols for attaining stable mixed hematopoietic chimerism in Miniature Swine, using MHC-matched donors and recipients. We have now assessed tolerance to donor-derived skin and cardiac allografts in these chimeric animals. Results. Skin-graft rejection was seen in four of six animals receiving skin grafts taken from the respective hematopoietic donors. In the other two animals, donor-derived skin grafts survived indefinitely. No cardiac-allograft rejection was observed in mixed-chimeric animals that received heart transplants from their hematopoietic donors, even in animals that had already rejected skin allografts from the same donors. In all animals assessed, in vitro hyporesponsiveness to donor hematopoietic cells persisted. Conclusion. These findings support the concept that skin expresses immunogenic alloantigens that either are not expressed or are not immunogenic in cardiac or hematopoietic tissue.
Kazuhiko Yamada - One of the best experts on this subject based on the ideXlab platform.
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Catechin and caffeine contents in green tea at different harvest periods and their metabolism in Miniature Swine
Food science & nutrition, 2019Co-Authors: Misato Wakamatsu, Kazuhiko Yamada, M Sekijima, Takehiro Iwanaga, Hiroki Yamanouchi, Hisashi Sahara, Rei Kuroda, Ayaka Yamamoto, Yuji Minami, Katsuko KajiyaAbstract:The catechin content in green tea leaves varies according to cultivation conditions such as intensity of solar radiation, temperature, and precipitation, and thus, there is ambiguity about the best harvest time for obtaining optimal functional effects. In this study, the Yabukita (ordinary) and Benifuki varieties, which contain methylated catechin, were used to determine the difference in green tea catechins according to harvest times and tea manufacturing processes. Caffeine determination was also carried out to provide information about green tea intake for all age-groups of children and pregnant women. Determining the quantity of each catechin was difficult because of degradation, polymerization, and isomerization that had occurred during heat-drying in the refining process. In addition, the absorption of catechin compounds was tested using Miniature Swine because of their functional and physiological similarity to humans. Benifuki tea leaves contained epigallocatechin-3-(3"-O-methyl) gallate (EGCg3"Me) instead of epigallocatechin-3-(4"-O-methyl) gallate (EGCg4"Me). However, EGCg4"Me was detected during the entire intake period, but EGCg3"Me was not detected in the blood of Miniature Swine fed Benifuki tea. It is possible that the position of the methyl group was modified by the pig metabolism. Furthermore, caffeine from both Yabukita and Benifuki tea varieties was found to be easily accumulated in Miniature Swine. These results suggest that nonrefined September-October picking tea (autumn and winter tea) of the Benifuki variety is preferable over the Yabukita variety for consumption by children and pregnant women owing to its lower caffeine content and higher content of methylated catechin.
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The Protective Effects of Carbon Monoxide Against Hepatic Warm Ischemia–Reperfusion Injury in MHC-Inbred Miniature Swine
Journal of Gastrointestinal Surgery, 2019Co-Authors: Takahiro Murokawa, Akira Shimizu, Takehiro Iwanaga, Hisashi Sahara, Mitsuhiro Sekijima, Thomas Pomposelli, Yurika Ichinari, Kazuhiko YamadaAbstract:Background The development of treatment strategies to protect against ischemia–reperfusion injury (IRI) to livers is important not only for liver surgeries but also in regard to increasing the utilization of livers from marginal donors. In this study, we examined whether inhalational carbon monoxide (CO) therapy reduced IRI after a 45-min (min) warm ischemia (WI) in a Miniature Swine model. Materials and Methods Six CLAWN Miniature Swine underwent a 45-min hepatic WI induced by clamping the portal vein and proper hepatic artery. Three animals were subjected to control conditions while the remaining three were treated with CO inhalation for a total of 345-min, including 120-min after reperfusion to maintain a concentration of CO-Hb under 15% (CO-treated group). IRI of the livers was evaluated by liver function tests, serum pro-inflammatory cytokines, and liver biopsies. Results All controls had statistically significant increased levels of liver enzymes compared to the CO-treated group ( p
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hydrogen sulfide prevents renal ischemia reperfusion injury in clawn Miniature Swine
Journal of Surgical Research, 2017Co-Authors: M Sekijima, Vincenzo Villani, H Sahara, Katsuyuki Miki, Yuichi Ariyoshi, Takehiro Iwanaga, Yusuke Tomita, Kazuhiko YamadaAbstract:Abstract Background Hydrogen sulfide (H2S) has recently been reported to demonstrate both antiinflammatory and cytoprotective effects; however, its efficacy has not been well documented in large animal models. In this study, we examined whether the administration of H2S offers cytoprotective effects on renal ischemia-reperfusion injury (IRI) in a preclinical Miniature Swine model. Methods Major histocompatibility complex-inbred, CLAWN Miniature Swine (n = 9) underwent a right nephrectomy, followed by induction of a 120-min period of warm ischemia via placement of clamps on the left renal artery and vein. Group 1 (n = 3) underwent renal ischemia without H2S administration. Groups 2 (n = 3) and 3 (n = 3) received Na2S (prodrug of H2S) 10 min before reperfusion of the ischemic kidneys followed by a 30-min of Na2S postreperfusion intravenously (group 2) or selective administration of Na2S via the left renal artery (group 3). IRI was assessed by kidney biopsies, levels of inflammatory cytokines in sera and kidney tissue. Results Animals in group 1 had significantly higher serum creatinine levels compared with animals in groups 2 and 3 (P Conclusions Na2S administration, especially via an organ selective approach, appears to potentially offer cytoprotective and antiinflammatory effects following renal IRI.
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the induction of tolerance of renal allografts by adoptive transfer in Miniature Swine
American Journal of Transplantation, 2013Co-Authors: Masayoshi Okumi, Vincenzo Villani, Beatrice Gillon, Masayuki Tasaki, Atsushi Hirakata, Joseph R Scalea, Taylor Cormack, David H. Sachs, Akira Shimizu, Kazuhiko YamadaAbstract:Our previous in vitro data have demonstrated that regulatory mechanisms are involved in tolerance of class I-mismatched renal allografts in Miniature Swine treated with 12 days of high dose Cyclsporin A. In this study, we attempted to induce tolerance of class I-mismatched kidneys by adoptive transfer of cells and/or kidneys from long-term tolerant animals. Fifteen SLA dd Miniature Swine received 1.5 Gy whole body irradiation and class I-mismatched (SLA gg ) kid
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Influence of the thymus on transplantation tolerance in Miniature Swine.
Transplantation Proceedings, 1997Co-Authors: Kazuhiko Yamada, Akira Shimizu, Pierre Gianello, F.l Ierino, Shane M. Meehan, Robert B. Colvin, David H. SachsAbstract:TOLERANCE to kidney allografts in Miniature Swine is uniformly induced by a 12-day course of cyclosporine A (CyA) across a two-haplotype class I disparity. Second kidney allografts, SLA-matched to the first donor, are accepted without additional immunosuppression, suggesting a systemic mechanism of tolerance. We studied the role of the thymus in tolerance to renal allografts in this model.
Clive Patience - One of the best experts on this subject based on the ideXlab platform.
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absence of replication competent human tropic porcine endogenous retroviruses in the germ line dna of inbred Miniature Swine
Journal of Virology, 2004Co-Authors: Linda Scobie, James Wood, Gary Quinn, Kristen M. Suling, Henk-jan Schuurman, Clive Patience, Samantha Taylor, Sharon Meikle, David OnionsAbstract:The potential transmission of porcine endogenous retroviruses (PERVs) has raised concern in the development of porcine xenotransplantation products. Our previous studies have resulted in the identification of animals within a research herd of inbred Miniature Swine that lack the capacity to transmit PERV to human cells in vitro. In contrast, other animals were capable of PERV transmission. The PERVs that were transmitted to human cells are recombinants between PERV-A and PERV-C in the post-VRA region of the envelope (B. A. Oldmixon, J. C. Wood, T. A. Ericsson, C. A. Wilson, M. E. White-Scharf, G. Andersson, J. L. Greenstein, H. J. Schuurman, and C. Patience, J. Virol. 76:3045-3048, 2002); these viruses we term PERV-A/C. This observation prompted us to determine whether these human-tropic replication-competent (HTRC) PERV-A/C recombinants were present in the genomic DNA of these Miniature Swine. Genomic DNA libraries were generated from one Miniature Swine that transmitted HTRC PERV as well as from one Miniature Swine that did not transmit HTRC PERV. HTRC PERV-A/C proviruses were not identified in the germ line DNAs of these pigs by using genomic mapping. Similarly, although PERV-A loci were identified in both libraries that possessed long env open reading frames, the Env proteins encoded by these loci were nonfunctional according to pseudotype assays. In the absence of a germ line source for HTRC PERV, further studies are warranted to assess the mechanisms by which HTRC PERV can be generated. Once identified, it may prove possible to generate animals with further reduced potential to produce HTRC PERV.
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Genotyping of Porcine Endogenous Retroviruses from a Family of Miniature Swine
Journal of virology, 2004Co-Authors: Gary Quinn, David H. Sachs, James Wood, Kristen M. Suling, Scott Arn, Henk-jan Schuurman, Clive PatienceAbstract:The identification of animals in an inbred Miniature Swine herd that consistently fail to produce replication- competent humantropic porcine endogenous retrovirus (PERV) has prompted studies on the biology of PERV in transmitter and nontransmitter animals. We analyzed PERV RNA transcript profiles in a family of inbred Miniature Swine (SLAd/d haplotype) in which individual members differed in their capacity to generate humantropic and ecotropic (i.e., pigtropic) virus. We identified unique HaeIII and HpaII gag restriction fragment length polymorphism (RFLP) profiles resulting from single nucleotide polymorphisms in blood cells; these were found only in animals that produced humantropic PERV. These HaeIII and HpaII gag RFLP profiles proved to be components of humantropic PERV as they were transmitted to 293 human target cells in vitro. The humantropic HaeIII and HpaII gag RFLP genotypes in the family of study were not present in other Miniature Swine in the herd that produced humantropic PERV, indicating that these RFLP profiles relate specifically to this family's lineage.
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Porcine Endogenous Retrovirus Transmission Characteristics of an Inbred Herd of Miniature Swine
Journal of virology, 2002Co-Authors: Beth A. Oldmixon, Henk-jan Schuurman, Thomas Ericsson, Goran Andersson, James C. Wood, Carolyn A. Wilson, M. E. White-scharf, Julia L. Greenstein, Clive PatienceAbstract:Here we report the identification of inbred Miniature Swine that failed to produce human-tropic replication-competent porcine endogenous retroviruses (HTRC PERVs), using in vitro coculture assays. When HTRC PERVs were isolated from transmitting animals, all were recombinant viruses, with the receptor-binding domain of PERV-A combining with PERV-C-related sequences.
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Identification of Novel Porcine Endogenous Betaretrovirus Sequences in Miniature Swine
Journal of virology, 2001Co-Authors: Thomas Ericsson, Beth A. Oldmixon, Clive Patience, Jonas Blomberg, Margaret Rosa, Goran AnderssonAbstract:PCR amplification of genomic DNA from Miniature Swine peripheral blood lymphocytes, using primers corresponding to highly conserved regions of the polymerase (pol) gene, allowed the identification of two novel porcine endogenous retrovirus (PERV) sequences, PMSN-1 and PMSN-4. Phylogenetic analyses of the nucleotide sequences of PMSN-1 and PMSN-4 revealed them to be most closely related to betaretroviruses. The identification of PERVs belonging to the Betaretrovirus genus shows that endogenous retroviruses of this family are more broadly represented in mammalian species than previously appreciated. Both sequences contained inactivating mutations, implying that these particular loci are defective. However, Southern blot analysis showed additional copies of closely related proviruses in the Miniature Swine genome. Analyses of fetal and adult Miniature Swine tissues revealed a broad mRNA expression pattern of both PMSN-1 and PMSN-4. The most abundant expression was detected in whole bone marrow c-kit(+) (CD117(+)) progenitor bone marrow cells, fetal liver, salivary gland, and thymus. It appears unlikely that functional loci encoding these novel PERV sequences exist, but this remains to be established. The betaretrovirus sequences described in this report will allow such investigations to be actively pursued.
David Onions - One of the best experts on this subject based on the ideXlab platform.
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Identification of Exogenous Forms of Human-Tropic Porcine Endogenous Retrovirus in Miniature Swine
Journal of virology, 2004Co-Authors: James Wood, Gary Quinn, Kristen M. Suling, Beth A. Oldmixon, Brian A. Van Tine, Robert A. Cina, Scott Arn, Christine Huang, Linda Scobie, David OnionsAbstract:The replication of porcine endogenous retrovirus subgroup A (PERV-A) and PERV-B in certain human cell lines indicates that PERV may pose an infectious risk in clinical xenotransplantation. We have previously reported that human-tropic PERVs isolated from infected human cells following cocultivation with Miniature Swine peripheral blood mononuclear cells (PBMC) are recombinants of PERV-A with PERV-C. Here, we report that these recombinants are exogenous viruses in Miniature Swine; i.e., they are not present in the germ line DNA. These viruses were invariably present in Miniature Swine that transmitted PERV to human cells and were also identified in some Miniature Swine that lacked this ability. These data, together with the demonstration of the absence of both replication-competent PERV-A and recombinant PERV-A/C loci in the genome of Miniature Swine (L. Scobie, S. Taylor, J. C. Wood, K. M. Suling, G. Quinn, C. Patience, H.-J. Schuurman, and D. E. Onions, J. Virol. 78:2502-2509, 2004), indicate that exogenous PERV is the principal source of human-tropic virus in these animals. Interestingly, strong expression of PERV-C in PBMC correlated with an ability of the PBMC to transmit PERV-A/C recombinants in vitro, indicating that PERV-C may be an important factor affecting the production of human-tropic PERV. In light of these observations, the safety of clinical xenotransplantation from Miniature Swine will be most enhanced by the utilization of source animals that do not transmit PERV to either human or porcine cells. Such animals were identified within the Miniature Swine herd and may further enhance the safety of clinical xenotransplantation.
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absence of replication competent human tropic porcine endogenous retroviruses in the germ line dna of inbred Miniature Swine
Journal of Virology, 2004Co-Authors: Linda Scobie, James Wood, Gary Quinn, Kristen M. Suling, Henk-jan Schuurman, Clive Patience, Samantha Taylor, Sharon Meikle, David OnionsAbstract:The potential transmission of porcine endogenous retroviruses (PERVs) has raised concern in the development of porcine xenotransplantation products. Our previous studies have resulted in the identification of animals within a research herd of inbred Miniature Swine that lack the capacity to transmit PERV to human cells in vitro. In contrast, other animals were capable of PERV transmission. The PERVs that were transmitted to human cells are recombinants between PERV-A and PERV-C in the post-VRA region of the envelope (B. A. Oldmixon, J. C. Wood, T. A. Ericsson, C. A. Wilson, M. E. White-Scharf, G. Andersson, J. L. Greenstein, H. J. Schuurman, and C. Patience, J. Virol. 76:3045-3048, 2002); these viruses we term PERV-A/C. This observation prompted us to determine whether these human-tropic replication-competent (HTRC) PERV-A/C recombinants were present in the genomic DNA of these Miniature Swine. Genomic DNA libraries were generated from one Miniature Swine that transmitted HTRC PERV as well as from one Miniature Swine that did not transmit HTRC PERV. HTRC PERV-A/C proviruses were not identified in the germ line DNAs of these pigs by using genomic mapping. Similarly, although PERV-A loci were identified in both libraries that possessed long env open reading frames, the Env proteins encoded by these loci were nonfunctional according to pseudotype assays. In the absence of a germ line source for HTRC PERV, further studies are warranted to assess the mechanisms by which HTRC PERV can be generated. Once identified, it may prove possible to generate animals with further reduced potential to produce HTRC PERV.