| progress and prospects: genetic engineering in xenotransplantation. | in this review, we summarize the work published over the last 2 years using genetic modifications of animals in the field of xenotransplantation. genetic engineering of the donor has become a powerful tool in xenotransplantation, both for the inactivation of one particular porcine gene and for the addition of human genes with the goal of overcoming xenogeneic barriers. we summarize the work relative to the knockout of the alpha1,3-galactosyltransferase gene, followed by genetic engineering aimed ... | 2008 | 18762806 |
| absence of transmission of potentially xenotic viruses in a prospective pig to primate islet xenotransplantation study. | shortage of human donor organs for transplantation has prompted usage of animals as an alternative donor source. pigs are the most acceptable candidate animals but issues of xenozoonoses remain. despite careful monitoring of designated pathogen free pigs there is still a risk that their tissues may carry infectious agents. thus xenotransplantation requires extensive pre-clinical study on safety of the graft especially for those viruses that are either potentially oncogenic and/or immunosuppressi ... | 2008 | 18814261 |
| absence of replication of porcine endogenous retrovirus and porcine lymphotropic herpesvirus type 1 with prolonged pig cell microchimerism after pig-to-baboon xenotransplantation. | porcine endogenous retrovirus (perv), porcine cytomegalovirus (pcmv), and porcine lymphotropic herpesvirus (plhv) are common porcine viruses that may be activated with immunosuppression for xenotransplantation. studies of viral replication or transmission are possible due to prolonged survival of xenografts in baboon recipients from human decay-accelerating factor transgenic or alpha-1,3-galactosyltransferase gene knockout miniature swine. ten baboons underwent xenotransplantation with transgeni ... | 2008 | 18829759 |
| no evidence for perv release by islet cells from german landrace pigs. | islet cells from pig could be used as an alternative to the current treatment of diabetic patients. however, xenotransplantation from pig to humans may be associated with the risk of transmission of porcine endogenous retroviruses (pervs) that are present in the genome of all pigs and infect human cells in vitro. although transplantation of pig islet cells for treatment of diabetes may be not accompanied by immunosuppression that may facilitate virus survival, since islets will be used encapsula ... | 2008 | 19034225 |
| genome areas with high gene density and cpg island neighborhood strongly attract porcine endogenous retrovirus for integration and favor the formation of hot spots. | porcine endogenous retroviruses (perv) are members of the gammaretrovirus genus and display integration preferences around transcription start sites, a finding which is similar to the preferences of the murine leukemia virus (mlv). our new genome-wide analysis of the integration profile of a recombinant perv (perv a/c), enabled us to examine more than 1,900 integration sites and identify 224 integration hot spots. investigation of the possible genome features involved in hot-spot formation revea ... | 2009 | 19036816 |
| identification of full-length proviral dna of porcine endogenous retrovirus from chinese wuzhishan miniature pigs inbred. | existence of porcine endogenous retrovirus (perv) hinders pigs to be used in clinical xenotransplantation to alleviate the shortage of human transplants. chinese miniature pigs are potential organ donors for xenotransplantation in china. however, so far, an adequate level of information on the molecular characteristics of perv from chinese miniature pigs has not been available. we described here the cloning and characterization of full-length proviral dna of perv from chinese wuzhishan miniature ... | 2010 | 19070900 |
| transmission of porcine endogenous retrovirus to human cells in nude mouse. | xenotransplantation is associated with the risk of porcine endogenous retrovirus (perv) transmission, since it has been shown that perv can infect human cells in vitro (specke et al., virology 285, 177-180, 2001). we evaluated the possibility of perv infection of human cells in nude mice model. porcine kidney cells pk15 carrying perv and human liver cancer cells smmc-7721 were injected separately into the right and left axilla of nude mice, respectively. two months later, pig cytochrome oxidase ... | 2008 | 19143483 |
| identification of two distinct structural regions in a human porcine endogenous retrovirus receptor, hupar2, contributing to function for viral entry. | of the three subclasses of porcine endogenous retrovirus (perv), perv-a is able to infect human cells via one of two receptors, hupar1 or hupar2. characterizing the structure-function relationships of the two hupar receptors in perv-a binding and entry is important in understanding receptor-mediated gammaretroviral entry and contributes to evaluating the risk of zoonosis in xenotransplantation. | 2009 | 19144196 |
| no in vivo infection of triple immunosuppressed non-human primates after inoculation with high titers of porcine endogenous retroviruses. | porcine endogenous retroviruses (pervs) released from pig tissue can infect selected human cells in vitro and therefore represent a safety risk for xenotransplantation using pig cells, tissues, or organs. although pervs infect cells of numerous species in vitro, attempts to establish reliable animal models failed until now. absence of perv transmission has been shown in first experimental and clinical xenotransplantations; however, these trials suffered from the absence of long-term exposure (tr ... | 2009 | 19243559 |
| porcine endogenous retrovirus (perv) and its transmission characteristics: a study of the new zealand designated pathogen-free herd. | previously a strategy for monitoring of pigs intended for cell transplantation was developed and successfully applied to several representative herds in new zealand. a designated pathogen-free (dpf) herd has been chosen as a good candidate for xenotransplantation. this herd has previously tested free of infectious agents relevant to xenotransplantation and we present here an in depth study of porcine endogenous retrovirus (perv) transmission. a panel of assays that describes the constraints for ... | 2008 | 19364075 |
| distribution and expression of porcine endogenous retroviruses in multi-transgenic pigs generated for xenotransplantation. | multi-transgenic pigs produced for use in xenotransplantation have to be screened for the presence and expression of porcine endogenous retroviruses (perv) to select animals with low perv load. the production of transgenic pigs may also be associated with the integration of the transgene adjacent to or into the locus of a perv provirus, potentially leading to an enhanced virus expression. | 2009 | 19392721 |
| inhibition of porcine endogenous retrovirus (perv) replication by hiv-1 gene expression inhibitors. | porcine endogenous retrovirus (perv) is persistently integrated into the host genomic dna as a provirus and released from a variety of porcine cells. perv infects a certain range of human cells, which is a major concern in xenotransplantation. therefore, the use of viral gene expression inhibitors could be envisaged, if they reduce perv production from porcine organs and minimize viral transmission to human recipients. in the present study, four hiv-1 gene expression inhibitors were examined for ... | 2009 | 19414036 |
| porcine endogenous retrovirus and other viruses in xenotransplantation. | potential transmission of zoonotic porcine viruses is a major safety issue in xenotransplantation. this review will first summarize recent studies involving transmission and control of the major concern, porcine endogenous retrovirus (perv). second, the potential for zoonotic transfer and safety measures required against other viruses of concern will be discussed. | 2009 | 19469034 |
| characterization of the replication-competent porcine endogenous retrovirus class b molecular clone originated from korean domestic pig. | xenotransplantation from pigs offers an opportunity to resolve the shortage of human organs. the porcine endogenous retrovirus (perv) cannot be eliminated because of its presence in the germline dna. three subgroups of the replication-competent perv (perv-a, perv-b, and perv-c) have been identified in pigs. we constructed a molecular clone of perv-b from a korean domestic pig bac clone containing perv genomes, and its replication competency was characterized in human cells. the pol region of per ... | 2009 | 19543822 |
| production of transgenic pigs that express porcine endogenous retrovirus small interfering rnas. | the presence of multiple copies of porcine endogenous retrovirus (perv) within the pig genome, and the demonstration that replication competent perv, that infect human cells in culture, can be isolated from pig cells, directly impacts the drive towards the development of pigs for xenotransplantation. the development of technology to produce pigs that do not propagate perv has the potential to facilitate the development of xenotransplantation products for human use, and as such, is the focus of t ... | 2009 | 19566656 |
| porcine endogenous retrovirus released by a bioartificial liver infects primary human cells. | porcine endogenous retrovirus (perv) remains a safety risk in pig-to-human xenotransplantation. there is no evidence of in vivo productive infection in humans because perv is inactivated by human serum. however, perv can infect human cell lines and human primary cells in vitro and inhibit human immune functions. | 2009 | 19686312 |
| the international xenotransplantation association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes-- executive summary. | the international xenotransplantation association islet xenotransplantation consensus statement describes the conditions for undertaking clinical trials of porcine islet products in type 1 diabetes. chapter 1 reviews the key ethical requirements and progress toward the definition of an international regulatory framework for clinical trials of xenotransplantation. chapters 2 to 7 provide in depth and agreed-upon recommendations on source pigs, pig islet product manufacturing and release testing, ... | 2009 | 19799759 |
| the international xenotransplantation association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 2: source pigs. | an islet xenotransplantation product includes live cells from a non-human source, in this study, a pig source. a live product cannot be subjected to conventional disinfection, and therefore the source pig must be depleted of infectious agents that can transmit to the recipient and cause disease. among other requirements, regulatory guidances specify that donor animals fulfill the designated pathogen-free (dpf) status. donor pigs fulfilling dpf status are generally bred and maintained in biosecur ... | 2009 | 19799761 |
| the international xenotransplantation association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 5: strategies to prevent transmission of porcine endogenous retroviruses. | xenotransplantation using porcine cells, tissues, or organs may offer a potential solution for the shortage of allogeneic human organs. prior to the clinical use of porcine xenotransplants, three main hurdles must be overcome: immunologic rejection, physiologic incompatibility, and risk of transmission of porcine pathogens. designated pathogen-free breeding of pigs can prevent transmission of most porcine microbes. however, this is not possible in the case of porcine endogenous retroviruses (per ... | 2009 | 19799764 |
| a newly cloned pig dolichyl-phosphate mannosyl-transferase for preventing the transmission of porcine endogenous retrovirus to human cells. | porcine endogenous retrovirus (perv) is a major problem associated with successful clinical xenotransplantation. in our previous study, reducing the high mannose type of n-glycan content proved to be very effective in downregulating perv infectivity. in this study, dolichyl-phosphate mannosyltransferase (d-p-m), an enzyme related to the early stages of n-linked sugar synthesis was studied. the pig cdna of the encoding d-p-m was newly isolated. the rna interference (sirna) for the d-p-m was appli ... | 2010 | 19912589 |
| unusual permeability of porcine endogenous retrovirus subgroup a through membrane filters. | in xenotransplantation from pigs to humans, a bio-artificial endocrine pancreas (bio-aep), in which pancreatic endocrine cells are encapsulated within a semipermeable membrane of 100 nm pore size, has been developed. we evaluated the permeability of porcine endogenous retroviruses (pervs) through membrane filters using a pseudotype virus (lacz(perv-a)) containing a viral core derived from murine leukemia virus and an envelope (env) from perv subgroup a. contrary to our expectations, lacz(perv-a) ... | 2010 | 19915326 |
| comparison of the age-related porcine endogenous retrovirus (perv)expression using duplex rt-pcr. | porcine endogenous retroviruses (pervs) are members of family retroviridae, genus gamma retrovirus, and transmitted by both horizontally and vertically like other endogenous retroviruses (ervs). perv was initially described in the 1970s having inserted its gene in the host genome of different pig breeds, and three classes, perv-a, perv-b, and perv-c are known. the therapeutic use of living cells, tissues, and organs from animals called xenotransplantation might relieve the limited supply of allo ... | 2009 | 19934597 |
| studies on long-term infection of human cells with porcine endogenous retrovirus. | a major concern in pig-to-human xenotransplantations is the potential risk of transmission of porcine endogenous retroviruses (pervs) integrated in the pig genome. our previous work has shown that perv provirus genes and gag protein can be detected in human embryonic kidney hek-293 cells during a long-term infection with perv (yu et al., transplant. proc. 37, 496-499, 2005). in this study, we continued studying the long-term (>6 months) perv infection of hek-293 cells. the results showed no sign ... | 2009 | 19941398 |
| investigation of porcine endogenous retrovirus in the conservation population of ningxiang pig. | porcine endogenous retrovirus (perv) varies between pig breeds. screening and analysis of perv in putative pig breeds may provide basic parameters to evaluate the biological safety of xenotransplantation from pigs to humans. in this study, perv was investigated among the conservation population of the ningxiang pig. the result revealed that the genotype of perv distribution was subtype a, 100%; subtype b, 100%; and subtype c, 100%. the env sequences of perv-a and -b showed 11 clones detected by ... | 2009 | 20005405 |
| regulation of porcine endogenous retrovirus release by porcine and human tetherins. | the risk of transmission of porcine endogenous retrovirus (perv) is one of the major safety issues in xenotransplantation. human tetherin, recently described as an antiviral protein able to inhibit the release of enveloped viruses, and its porcine homologue were shown to inhibit perv release from producer cells, establishing themselves as candidate molecules to suppress perv production in porcine xenografts by animal engineering. | 2010 | 20015985 |
| no evidence of porcine endogenous retrovirus in patients with type 1 diabetes after long-term porcine islet xenotransplantation. | xenotransplantation is a promising alternative for donor shortage to ameliorate physiologic and metabolic disorders. the major concern for xenotransplant is the risk of zoonosis mainly by the porcine endogenous retrovirus (perv), presentation in the piglet genome. twenty-three patients with type 1 diabetes were transplanted with porcine islets using collagen-generating devices which were implanted subcutaneously in the anterior wall of the abdomen. clinical characteristics and metabolic tests we ... | 2010 | 20029803 |
| critical issues related to porcine xenograft exposure to human viruses: lessons from allotransplantation. | xenotransplantation of tissues from swine into humans poses the threat of bidirectional transfer of porcine or human microorganisms to the recipient or to the xenograft, respectively. this review focuses on recipient-derived infection. recent data are reviewed that assess the susceptibility of porcine cells to human viruses. on the basis of the experience in allotransplantation, potential consequences for the xenograft are discussed. | 2010 | 20061950 |
| an effective method for the quantitative detection of porcine endogenous retrovirus in pig tissues. | xenotransplantation shows great promise for providing a virtually limitless supply of cells, tissues, and organs for a variety of therapeutical procedures. however, the potential of porcine endogenous retrovirus (perv) as a human-tropic pathogen, particularly as a public health risk, is a major concern for xenotransplantation. this study focus on the detection of copy number in various tissues and organs in banna minipig inbreed (bmi) from 2006 to 2007 in west china hospital, sichuan university. ... | 2010 | 20108128 |
| [receptors for animal retroviruses]. | diseases caused by animal retroviruses have been recognized since 19th century in veterinary field. most livestock and companion animals have own retroviruses. to disclose the receptors for these retroviruses will be useful for understanding retroviral pathogenesis, developments of anti-retroviral drugs and vectors for human and animal gene therapies. of retroviruses in veterinary field, receptors for the following viruses have been identified; equine infectious anemia virus, feline immunodefici ... | 2009 | 20218331 |
| expression of complement regulatory protein on porcine endogenous retrovirus (perv) depends on molecular size. | expression of complement regulatory proteins (crp) on pig cells is an effective means to avoid hyperacute rejection. however, pig endogenous retrovirus (perv) from pig cells transfected with crp may acquire resistance to human serum (hs). the present study investigated the size limitations of the transfected crp that can be easily expressed and function on perv particles. cdnas of various sized daf(cd55)s, including single-, double-, triple-, tetra-, as well as 2.1- and 2.2-daf, were prepared. p ... | 2010 | 20226243 |
| real-time quantitative polymerase chain reaction with sybr green i detection for estimating copy numbers of porcine endogenous retrovirus from chinese miniature pigs. | porcine endogenous retrovirus (perv) in the pig genome represents a potential infectious risk in xenotransplantation. chinese miniature pigs have been considered to be potential organ donors in china. however, an adequate level of information on perv from chinese miniature pigs has not been available. we established an sybr green i-based real-time quantitative polymerase chain reaction (pcr) assay for estimating copy numbers of perv integrated in the host genome. the assay was 100-fold more sens ... | 2010 | 20620553 |
| characterisation of a human cell-adapted porcine endogenous retrovirus perv-a/c. | porcine endogenous retroviruses (pervs) pose a potential risk for xenotransplantation using pig cells, tissues or organs. a special threat comes from viruses generated by recombination between human-tropic perv-a and ecotropic perv-c. serial passages of a recombinant perv-a/c on human 293 cells resulted in increased infectious titers and a multimerization of transcription factor binding sites in the viral long terminal repeat (ltr). in contrast to the ltr, the sequence of the env gene did not ch ... | 2010 | 20657519 |
| simultaneous detection and subtyping of porcine endogenous retroviruses proviral dna using the dual priming oligonucleotide system. | the purpose of this study was to develop a multiplex pcr that can detect porcine endogenous retrovirus (perv) proviral genes (pol, enva, envb, envc) and porcine mitochondrial dna, using a dual priming oligonucleotide (dpo) system. the primer specifically detected the perv proviral genes pol, enva, envb, envc, and porcine mitochondrial dna only in samples of pig origin. the sensitivity of the primer was demonstrated by simultaneous amplification of all 5 target genes in as little as 10 pg of pig ... | 2010 | 20706036 |
| analysis of the molecular and regulatory properties of active porcine endogenous retrovirus gamma-1 long terminal repeats in kidney tissues of the nih-miniature pig. | the pig genome contains the gamma 1 family of porcine endogenous retroviruses (pervs), which are a major obstacle to the development of successful xenotransplantation from pig to human. long terminal repeats (ltrs) found in pervs are known to be essential elements for the control of the transcriptional activity of single virus by different transcription factors (tfs). to identify transcribed perv ltr elements, rt-pcr and dna sequencing analyses were performed. twenty-nine actively transcribed lt ... | 2010 | 20811814 |
| molecular characterization of long terminal repeat of porcine endogenous retroviruses in chinese pigs. | pigs offer an unlimited source of xenografts for humans. however, vertically transmitted porcine endogenous retrovirus (perv) poses an infectious risk in the course of pig-to-human transplantation. in this study, we characterized perv long terminal repeat (ltr) sequences from three species of chinese pigs banna minipig inbred (bmi), wu-zhi-shan pig (wzsp), and neijiang pig (njp-a), and compared them with those of known pervs (perv-a, perv-b, perv-c, perv-nih, and 293-perv-43). genomic dna extrac ... | 2010 | 20822308 |
| increased neutralizing antibody response after simultaneous immunization with leucogen and the feline leukemia virus transmembrane protein. | to develop improved vaccination strategies against feline leukemia virus (felv), rats were immunized with the transmembrane envelope protein p15e of felv alone or in combination with the commercial vaccine leucogen® comprising the nonglycosylated felv surface envelope protein. binding and neutralizing antibodies were induced in both groups and in the group immunized with leucogen alone. higher titers of antibodies neutralizing felv were induced by simultaneous immunization with leucogen and p15e ... | 2011 | 20829603 |
| islet cell transplantation for type 1 diabetes. | islet transplantation is an attractive concept for the treatment of type 1 diabetes because of its potential high efficacy and minimal invasion to patients. the treatment may effectively control blood glucose for brittle type 1 diabetes, resulting in a marked reduction in hypoglycemic episodes and improvements in hba1c. in addition, approximately 70% of transplanted type 1 diabetic patients have achieved insulin independence. however, there are still important issues to be addressed before this ... | 2010 | 20923470 |
| the rapid production of high-titer porcine endogenous retrovirus(perv)-b env pseudotype and construction of an egfp-expressing replication competent perv-a vector. | porcine endogenous retroviruses (pervs) present a unique concern associated with xenotransplantation because they have been shown to infect certain human cells in vitro and it is also difficult to generate herds of pigs free of pervs. a simple system for the production of high-titer momlv-perv pseudotypes is reported; an egfp-expressing replication-competent molecular clone that allows direct measurement of titer was also constructed. to improve the mlv-based retroviral vector system, a 2.1-kb p ... | 2010 | 20933542 |
| suboptimal porcine endogenous retrovirus infection in non-human primate cells: implication for preclinical xenotransplantation. | porcine endogenous retrovirus (perv) poses a potential risk of zoonotic infection in xenotransplantation. preclinical transplantation trials using non-human primates (nhp) as recipients of porcine xenografts present the opportunity to assess the zoonosis risk in vivo. however, perv poorly infects nhp cells for unclear reasons and therefore nhp may represent a suboptimal animal model to assess the risk of perv zoonoses. we investigated the mechanism responsible for the low efficiency of perv-a in ... | 2010 | 20949092 |
| epigenetic regulation on the 5'-proximal cpg island of human porcine endogenous retrovirus subgroup a receptor 2/gpr172b. | porcine endogenous retroviruses (pervs) have been considered one of the major risks of xenotransplantation from pigs to humans. perv-a efficiently utilizes human perv-a receptor 2 (hupar-2)/gpr172b to infect human cells; however, there has been no study on the regulation mechanisms of hupar-2/gpr172b expression. in this study, we examined the expression of hupar-2/gpr172b from the standpoint of epigenetic regulation and discussed the risks of perv-a infection in xenotransplantation. quantitative ... | 2010 | 20951222 |
| long-term absence of porcine endogenous retrovirus infection in chronically immunosuppressed patients after treatment with the porcine cell-based academic medical center bioartificial liver. | clinical use of porcine cell-based bioartificial liver (bal) support in acute liver failure as bridging therapy for liver transplantation exposes the patient to the risk of transmission of porcine endogenous retroviruses (pervs) to human. this risk may be enhanced when patients receive liver transplant and are subsequently immunosuppressed. as further follow-up of previously reported patients (di nicuolo et al. 2005), an assessment of perv infection was made in the same patient population pharma ... | 2010 | 21158944 |
| mapping of a neutralizing epitope in the surface envelope protein of porcine endogenous retrovirus subgroup b. | pigs are thought to be the most suitable donor animal for xenotransplantation. however, pigs harbour potentially hazardous infectious agents, termed porcine endogenous retroviruses (pervs), in their genome. in this study, we generated a mab against perv-b surface (su) envelope protein (env), designated krt1. krt1 binding was detected by an indirect immunofluorescence assay and flow cytometric analysis on cells infected with perv-b. krt1 neutralized perv-b pseudotype virus and specifically recogn ... | 2011 | 21228129 |
| generation of neutralising antibodies against porcine endogenous retroviruses (pervs). | antibodies neutralising porcine endogenous retroviruses (pervs) were induced in different animal species by immunisation with the transmembrane envelope protein p15e. these antibodies recognised epitopes, designated e1, in the fusion peptide proximal region (fppr) of p15e, and e2 in the membrane proximal external region (mper). e2 is localised in a position similar to that of an epitope in the transmembrane envelope protein gp41 of the human immunodeficiency virus-1 (hiv-1), recognised by the mo ... | 2011 | 21237477 |
| fluidized-bed bioartificial liver assist devices (blads) based on microencapsulated primary porcine hepatocytes have risk of porcine endogenous retroviruses transmission. | bioartificial liver assist devices (blads) are expected to bridge liver failure patients to liver transplantation, but porcine endogenous retroviruses (pervs) still pose a potential risk in pig-to-human xenotransplantation and thereby limit the use of bioartificial liver therapy. in our lab, fluidized-bed blads based on microencapsulated primary porcine hepatocytes have been successfully used to treat liver failure pigs. we detected the risk of pervs transmission of microencapsulated primary por ... | 2010 | 21286347 |
| restriction of porcine endogenous retrovirus by porcine apobec3 cytidine deaminases. | xenotransplantation of porcine cells, tissues, and organs shows promise to surmount the shortage of human donor materials. among the barriers to pig-to-human xenotransplantation are porcine endogenous retroviruses (perv) since functional representatives of the two polytropic classes, perv-a and perv-b, are able to infect human embryonic kidney cells in vitro, suggesting that a xenozoonosis in vivo could occur. to assess the capacity of human and porcine cells to counteract perv infections, we an ... | 2011 | 21307203 |
| detection of porcine endogenous retrovirus (perv) viremia in diseased versus healthy us pigs by qualitative and quantitative real-time rt-pcr. | previous studies have linked levels of porcine endogenous retroviruses (perv) with poor health and disease in pigs. to determine the levels of expression of pervs and their potential association with disease expression, real-time reverse transcriptase (rt) pcr assays were used to assess perv-abc, perv-c and perv-a/c levels in three commercial swine operations in the united states. pigs (n = 204) aged 3-25 weeks were screened, and all 369 serum samples collected were found to be positive for perv ... | 2011 | 21396084 |
| repression of porcine endogenous retrovirus infection by human apobec3 proteins. | it has been shown that porcine endogenous retrovirus (perv) can infect human cells, indicating that perv transmission poses a serious concern in pig-to-human xenotransplantation. a number of recent studies have reported on retrovirus interference by antiviral proteins. the most potent antiviral proteins are members of the apobec family of cytidine deaminases, which are involved in defense against retroviral attack. these proteins are present in the cytoplasm of mammalian cells and inhibit retrov ... | 2011 | 21396348 |
| evaluation of the potential risk of porcine endogenous retrovirus (perv) infection in nude mice. | nude mice (balb/c) were grafted with human 293 cells and perv (porcine endogenous retrovirus)-ires-egfp (a packageable retroviral vector plasmid containing an internal ribosome entry site-enhanced green fluorescent protein)-producing pig pk15 cells in order to determine whether the pig cells could transmit perv-ires-egfp to mice and human 293 cells in vivo. none of the transplanted human 293 cell lines were infected by perv, but pcr analysis identified perv-b provirus integration into both the h ... | 2011 | 21532322 |
| development of sensitive methods for detection of porcine endogenous retrovirus-c (perv-c) in the genome of pigs. | porcine endogenous retroviruses (perv) represent a risk for xenotransplantation using pig cells, tissues or organs. perv-a and perv-b are present in the genome of all pigs and both infect human cells in vitro. perv-c infects only pig cells and it is integrated in the genome of most, but not all pigs. recombinants between perv-a and perv-c were described that infect human cells and replicate at high titres. to avoid such recombinations, perv-c positive animals should not be used for breeding anim ... | 2011 | 21539860 |
| multiplex high resolution melting assay for estimation of porcine endogenous retrovirus (perv) relative gene dosage in pigs and detection of perv infection in xenograft recipients. | porcine endogenous retrovirus (perv) poses an infectious risk in the field of xenotransplantation. this risk may be mitigated by breeding selectively animals bearing favorable perv genetic characteristics including pigs with low levels of perv integrated in the genome. a real-time quantitative polymerase chain reaction (pcr) assay employing the roche high resolution melting (hrm) master was used to estimate the relative gene dosage of perv pol integrated within the pig genome. when assessed acro ... | 2011 | 21545811 |
| identification of developmental competence-related genes in mature porcine oocytes. | oocyte competence is a key factor limiting female fertility, yet the underlying molecular mechanisms that contribute to oocyte competence remain unclear. the objective of this study was to elucidate specific genes whose function contributes to oocyte competence. we observed that 6 of 20 target genes examined were differentially expressed between adult (more competent) and prepubertal (less competent) porcine in vitro matured (ivm) oocytes. these genes were the cholesterol synthesis-related gene ... | 2011 | 21774025 |
| no enhanced expression and infectivity of porcine endogenous retrovirus in primary porcine hepatocytes with chitosan nanofiber scaffold. | our previous report suggested that chitosan nanofiber scaffold may find application in bioartificial livers for it could enhance the function of hepatocytes. this study was focused on its microbiological safety, that is, its influence on the expression and infectivity of porcine endogenous retrovirus (perv) in primary porcine hepatocytes. freshly isolated porcine hepatocytes were cultured with or without chitosan nanofiber scaffold (defined as exp group and ctr group) and porcine kidney 15 (pk15 ... | 2011 | 21830478 |
| influence of chitosan nanofiber scaffold on porcine endogenous retroviral expression and infectivity in pig hepatocytes. | to investigate the influence of chitosan nanofiber scaffold on the production and infectivity of porcine endogenous retrovirus (perv) expressed by porcine hepatocytes. | 2011 | 21734784 |
| Rapid determination of perv copy number from porcine genomic DNA by real-time polymerase chain reaction. | Here, we report the quantification of porcine endogenous retrovirus (PERV) copy numbers using real time PCR. After generating standard curves using plasmid DNA, copy numbers were determined for PERV pol and for a housekeeping gene, porcine estrogen receptor2 (ER2) with the same amount of genomic DNA. Using this method, we examined 6 pig breeds in Korea including two breeds of miniature pig, one domestic pig from Jeju, and imported pig breeds, Duroc, Landrace, and Yorkshire. All breeds showed PER ... | 2011 | 22132811 |
| xenotransplantation of galactosyl-transferase knockout, cd55, cd59, cd39, and fucosyl-transferase transgenic pig kidneys into baboons. | galactosyl-transferase knockout (gt-ko) pigs represent the latest major progress to reduce immune reactions in xenotransplantation. however, their organs are still subject to rapid humoral rejection involving complement activation requiring the ongoing development of further genetic modifications in the pig. in a pig-to-baboon renal transplantation setting, we have used donor pigs that are not only gt-ko, but also transgenic for human cd55 (hcd55), hcd59, hcd39, and fucosyl-transferase (hht). we ... | 2011 | 22099813 |
| reduction of n-tropic mutant porcine endogenous retrovirus infectivity by human tripartite motif-containing 5-isoform alpha. | in cases of retroviral infection, the host cell deploys antiviral proteins as a type of innate immunity. tripartite motif-containing 5-isoform alpha (trim5α) is a potent antiviral protein. trim5α has been reported to restrict human immunodeficiency virus (hiv) 1 infection in rhesus monkey cells by targeting the incoming viral capsid at the postentry or preintegration stage of the viral life cycle. as a consequence, virus replication and reverse transcription are interrupted. trim5α of human orig ... | 2011 | 21911161 |
| Characterization of porcine endogenous retrovirus clones from the NIH miniature pig BAC library. | Pigs have been considered as donors for xenotransplantation in the replacement of human organs and tissues. However, porcine endogenous retroviruses (PERVs) might transmit new infectious disease to humans during xenotransplantation. To investigate PERV integration sites, 45 PERV-positive BAC clones, including 12 PERV-A, 16 PERV-B, and 17 PERV-C clones, were identified from the NIH miniature pig BAC library. The analysis of 12 selected full-length sequences of PERVs, including the long terminal r ... | 2012 | 21912484 |
| genetic prevalence of porcine endogenous retrovirus in chinese experimental miniature pigs. | pig-to-human xenotransplantation poses the potential risk of interspecies transmission of porcine endogenous retrovirus (perv). the chinese experimental miniature pig may be used as a pig-to-human xenograft donor. however, data for the distribution of perv provirus in genomic dna and perv expression at the rna level for the chinese experimental miniature pig population are lacking. in this study, perv was investigated in this regard using polymerase chain reaction (pcr), real-time quantitative p ... | 2011 | 21911159 |
| emerging and re-emerging swine viruses. | in the past two decades or so, a number of viruses have emerged in the global swine population. some, such as porcine reproductive and respiratory syndrome virus (prrsv) and porcine circovirus type 2 (pcv2), cause economically important diseases in pigs, whereas others such as porcine torque teno virus (ttv), now known as torque teno sus virus (ttsuv), porcine bocavirus (pbov) and related novel parvoviruses, porcine kobuvirus, porcine toroviruses (ptov) and porcine lymphotropic herpesviruses (pl ... | 2012 | 22225855 |
| carbohydrate antigens. | purpose of review: to summarize the current knowledge of carbohydrate antigens as related to xenotransplantation. the emphasis is on non-gal carbohydrate antigens identified in many institutes. in addition, several topics such as glycosyltransferase-transgenic pigs, innate cell receptors and porcine endogenous retrovirus (perv) will be discussed. recent findings: studies related to igb3 and neoantigens after knocking out galt (ggta1) were reviewed. available data do not support the conclusion th ... | 2012 | 22262104 |
| a clinical trial of xenotransplantation of neonatal pig islets for diabetic patients. | to ascertain the safety and function of the transplantation of neonatal pig islets (npis) for diabetic patients. | 2011 | 22246351 |
| transmission of zoonoses in xenotransplantation: porcine endogenous retroviruses from an immunological and molecular point of view. | background and objectives: pigs offer an unlimited source of xenografts for humans. the use of transplants from animal origin offers a potential solution to the limited supply of human organs and tissues. however, like many other mammalian species, pigs harbor porcine endogenous retrovirus (perv), which are encoded in their genomic dna and are assumed to have been integrated into the porcine germ line more than 7.6 × 106 years ago and showing that the age correlates with the time of separation b ... | 2012 | 23897566 |
| xenotransplantation-associated infectious risk: a who consultation. | xenotransplantation carries the potential risk of the transmission of infection with the cells or tissues of the graft. the degree of risk is unknown in the absence of clinical trials. the clinical application of xenotransplantation has important implications for infectious disease surveillance, both at the national and international levels. preclinical data indicate that infectious disease events associated with clinical xenotransplantation from swine, should they occur, will be rare; data in h ... | 2012 | 22497509 |
| viral metagenomic analysis of bushpigs (potamochoerus larvatus) in uganda identifies novel variants of porcine parvovirus 4 and torque teno sus virus 1 and 2. | as a result of rapidly growing human populations, intensification of livestock production and increasing exploitation of wildlife habitats for animal agriculture, the interface between wildlife, livestock and humans is expanding, with potential impacts on both domestic animal and human health. wild animals serve as reservoirs for many viruses, which may occasionally result in novel infections of domestic animals and/or the human population. given this background, we used metagenomics to investig ... | 2012 | 22967311 |
| bortezomib, c1-inhibitor and plasma exchange do not prolong the survival of multi-transgenic galt-ko pig kidney xenografts in baboons. | galactosyl-transferase ko (galt-ko) pigs represent a potential solution to xenograft rejection, particularly in the context of additional genetic modifications. we have performed life supporting kidney xenotransplantation into baboons utilizing galt-ko pigs transgenic for human cd55/cd59/cd39/ht. baboons received tacrolimus, mycophenolate mofetil, corticosteroids and recombinant human c1 inhibitor combined with cyclophosphamide or bortezomib with or without 2-3 plasma exchanges. one baboon recei ... | 0 | 25612490 |
| molecular evolution of the porcine type i interferon family: subtype-specific expression and antiviral activity. | type i interferons (ifns), key antiviral cytokines, evolve to adapt with ever-changing viral threats during vertebrate speciation. due to novel pathogenic pressure associated with suidae speciation and domestication, porcine ifns evolutionarily engender both molecular and functional diversification, which have not been well addressed in pigs, an important livestock species and animal model for biomedical sciences. annotation of current swine genome assembly sscrofa10.2 reveals 57 functional gene ... | 2014 | 25372927 |
| computational evaluation of the strict master and random template models of endogenous retrovirus evolution. | transposable elements (tes) are dna sequences that are able to replicate and move within and between host genomes. their mechanism of replication is also shared with endogenous retroviruses (ervs), which are also a type of te that represent an ancient retroviral infection within animal genomes. two models have been proposed to explain te proliferation in host genomes: the strict master model (smm), and the random template (or transposon) model (tm). in smm only a single copy of a given te lineag ... | 2016 | 27649303 |
| complete genome sequence of a porcine endogenous retrovirus isolated from a bama minipig in guangxi, southern china. | a porcine endogenous retrovirus (perv) strain, perv-a-bm, was isolated from a bama minipig in guangxi, china. this is the first entire genome sequence of perv isolated from guangxi bama minipigs. the isolate is closely related to isolates from wuzhishan miniature pigs and distantly related to isolates from large white pigs. | 2015 | 26067965 |
| optimization of virus detection in cells using massively parallel sequencing. | massively parallel sequencing (mps)-based virus detection has potential regulatory applications. we studied the ability of one of these approaches, based on degenerate oligonucleotide primer (dop)-polymerase chain reaction (pcr), to detect viral sequences in cell lines known to express viral genes or particles. dop-pcr was highly sensitive for the detection of small quantities of isolated viral sequences. detected viral sequences included nodavirus, bracovirus, and endogenous retroviruses in hig ... | 2014 | 24309095 |
| quantitative detection of residual porcine host cell dna by real-time pcr. | all biological products are derived from complex living systems and are often mixed with large numbers of impurities. for reasons of safety, residual host-cell dna must be eliminated during processing. to assay host-cell dna content in biopharmaceutical products derived from porcine sources, this study applies the quantitative real-time polymerase chain reaction (q-pcr) method. the optimized assay in this study is based on the pol region of the porcine endogenous retrovirus (perv). assay validat ... | 2014 | 24394374 |
| immunising with the transmembrane envelope proteins of different retroviruses including hiv-1: a comparative study. | the induction of neutralizing antibodies is a promising way to prevent retrovirus infections. neutralizing antibodies are mainly directed against the envelope proteins, which consist of two molecules, the surface envelope (su) protein and the transmembrane envelope (tm) protein. antibodies broadly neutralizing the human immunodeficiencvy virus-1 (hiv-1) and binding to the tm protein gp41 of the virus have been isolated from infected individuals. their epitopes are located in the membrane proxima ... | 2013 | 23249763 |
| comparison between s+l- assay and lacz marker rescue assay for detecting replication-competent gammaretroviruses. | to avoid contamination of adventitious gammaretroviruses in biological products such as vaccines, it is necessary to check the master seed cells for manufacturing. there are several assays to detect infectious gammaretroviruses. among these, sarcoma-positive, leukemia-negative (s+l-) assay is a classical infectivity assay, which is often recommended in governmental guidelines. the s+l- cells used in s+l- assay generate unique focus upon the infection of replication-competent gammaretroviruses. a ... | 2015 | 26164289 |
| mutations altering the gammaretrovirus endoproteolytic motif affect glycosylation of the envelope glycoprotein and early events of the virus life cycle. | previously, we found that mutation of glutamine to proline in the endoproteolytic cleavage signal of the perv-c envelope (rqkk to rpkk) resulted in non-infectious vectors. here, we show that rpkk results in a non-infectious vector when placed in not only a perv envelope, but also the envelope of a related gammaretrovirus, felv-b. the amino acid substitutions do not prevent envelope precursor cleavage, viral core and genome assembly, or receptor binding. rather, the mutations result in the format ... | 2015 | 25462351 |
| koala retroviruses: characterization and impact on the life of koalas. | koala retroviruses (korv) have been isolated from wild and captive koalas in australia as well as from koala populations held in zoos in other countries. they are members of the genus gammaretrovirus, are most closely related to gibbon ape leukemia virus (galv), feline leukemia virus (felv) and porcine endogenous retrovirus (perv) and are likely the result of a relatively recent trans-species transmission from rodents or bats. the first korv to be isolated, korv-a, is widely distributed in the k ... | 2013 | 24148555 |
| comparison of the convergent receptor utilization of a retargeted feline leukemia virus envelope with a naturally-occurring porcine endogenous retrovirus a. | in vitro screening of randomized felv envelope libraries identified the cp isolate, which enters cells through hupar-1, one of two human receptors utilized by porcine endogenous retrovirus-a (perv-a), a distantly related gammaretrovirus. the cp and perv-a envs however, share little amino acid homology. their receptor utilization was examined to define the common receptor usage of these disparate viral envs. we demonstrate that the receptor usage of cp extends to hupar-2 but not to the porcine re ... | 2012 | 22405627 |
| first update of the international xenotransplantation association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 5: recipient monitoring and response plan for preventing disease transmission. | xenotransplantation of porcine cells, tissues, and organs may be associated with the transmission of porcine microorganisms to the human recipient. a previous, 2009, version of this consensus statement focused on strategies to prevent transmission of porcine endogenous retroviruses (pervs). this version addresses potential transmission of all porcine microorganisms including monitoring of the recipient and provides suggested approaches to the monitoring and prevention of disease transmission. pr ... | 2016 | 26918415 |
| induction of perv antigen in porcine peripheral blood mononuclear cells by human herpesvirus 1. | xenotransplantation represents one of alternative candidates for allotransplantation due to the chronic shortage of suitable human tissues; however, many obstacles remain. expression and release of endogenous retroviral antigens by porcine cells after transplantation may evoke adverse immune responses in human subjects. here, we examined whether human herpesvirus 1 (hhv-1) could induce the production of porcine endogenous retrovirus (perv) antigens in porcine peripheral blood mononuclear cells ( ... | 2015 | 25716804 |
| neutralization of porcine endogenous retrovirus by antibodies against the membrane-proximal external region of the transmembrane envelope protein. | immunization of different species including goats, rats, hamsters and guinea pigs with the recombinant ectodomain of the transmembrane envelope (tm) protein p15e of porcine endogenous retrovirus (perv) has been shown to result in the production of virus-neutralizing antibodies. the sera recognize two groups of epitopes, one located in the fusion peptide-proximal region (fppr) and the second in the membrane-proximal external region (mper) of p15e. most interestingly, the epitopes in the mper are ... | 2013 | 23223617 |
| transmission of porcine endogenous retrovirus produced from different recipient cells in vivo. | humanized pigs have been developed to reduce the incidence of immune rejection in xenotransplantation, but significant concerns remain, such as transmission of viral zoonosis. porcine endogenous retroviruses (perv), which exist in the genome of pigs, are produced as infectious virions from all porcine cells and cause zoonosis. here, we examined the possibility of zoonosis of hosts under conditions of immune suppression or xenotransplantation of cells producing host-adapted viruses. upon transpla ... | 2016 | 27832080 |
| new phase of growth for xenogeneic-based bioartificial organs. | in this article, we examine the advanced clinical development of bioartificial organs and describe the challenges to implementing such systems into patient care. the case for bioartificial organs is evident: they are meant to reduce patient morbidity and mortality caused by the persistent shortage of organs available for allotransplantation. the widespread introduction and adoption of bioengineered organs, incorporating cells and tissues derived from either human or animal sources, would help ad ... | 2016 | 27657057 |
| chemiluminescent detection for estimating relative copy numbers of porcine endogenous retrovirus proviruses from chinese minipigs based on magnetic nanoparticles. | chinese bama minipigs could be potential donors for the supply of xenografts because they are genetically stable, highly inbred, and inexpensive. however, porcine endogenous retrovirus (perv) is commonly integrated in pig genomes and could cause a cross-species infection by xenotransplantation. for screening out the pigs with low copy numbers of perv proviruses, we have developed a novel semiquantitative analysis approach based on magnetic nanoparticles (mnps) and chemiluminescence (cl) for esti ... | 2016 | 27427744 |
| susceptibility of porcine endogenous retrovirus to anti-retroviral inhibitors. | porcine endogenous retrovirus (perv) is an endogenous retrovirus that poses a risk of iatrogenic transmission in the context of pig-to-human xenotransplantation. the lack of a means to control perv infection in the context of pig-to-human xenotransplantation is a major concern in the field. in this study, we set out to evaluate the ability of currently licensed anti-hiv drugs, and other types of anti-retroviral compounds, to inhibit perv infection in vitro. | 2016 | 27028725 |
| current status and future of clinical islet xenotransplantation. | β-cell replacement therapy, including allogeneic pancreas and islet transplantation, can normalize hba1c levels in unstable type 1 diabetic (t1d) patients, but a donor shortage is a serious issue. to overcome this problem, xenotransplantation is an attractive option. in fact, islet transplantation from porcine pancreata was performed in the 1990s, which opened the door for islet xenotransplantation, but the possibility of porcine endogenous retrovirus (perv) infection was raised, which has restr ... | 2016 | 26987992 |
| first update of the international xenotransplantation association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 2a: source pigs--preventing xenozoonoses. | chapter 2 of the original consensus statement published in 2009 by ixa represents an excellent basis for the production of safe donor pigs and pig-derived materials for porcine islet xenotransplantation. it was intended that the consensus statement was to be reviewed at interval to remain relevant. indeed, many of the original salient points remain relevant today, especially when porcine islet xenotransplantation is performed in conjunction with immunosuppressants. however, progress in the field ... | 2016 | 26940608 |
| characterization of complete genome sequences of a porcine endogenous retrovirus isolated from china bama minipig reveals an evolutionary time earlier than that of isolates from european minipigs. | a porcine endogenous retroviruses (perv) isolate, perv-a-bm, was isolated from a guangxi bama minipig in china. | 2016 | 26915872 |
| no transmission of porcine endogenous retrovirus in an acute liver failure model treated by a novel hybrid bioartificial liver containing porcine hepatocytes. | a novel hybrid bioartificial liver (hbal) was constructed using an anionic resin adsorption column and a multi-layer flat-plate bioreactor containing porcine hepatocytes co-cultured with bone marrow mesenchymal stem cells (mscs). this study aimed to evaluate the microbiological safety of the hbal by detecting the transmission of porcine endogenous retroviruses (pervs) into canines with acute liver failure (alf) undergoing hbal. | 2015 | 26459725 |
| a study on the susceptibility of allogeneic human hepatocytes to porcine endogenous retrovirus. | porcine endogenous retrovirus (perv) is a virus that can be integrated into porcine genome. it has been proved that perv can infect the cells of a variety of species. however, little is known about the infectivity of perv to human hepatocytes. the present study focused on the susceptibility of primary human hepatocytes to perv. | 2015 | 26439047 |
| regulatory aspects of clinical xenotransplantation. | xenotransplantation attracted interest from regulatory authorities, particularly after the demonstration of pig-to-human transmission of porcine endogenous retrovirus (1996). this added to the risk of a product, resulting in a guidance of the us food and drug administration (2003). this addresses the full flow chart in product manufacturing, starting with the designated pathogen-free status of the source animal; and special aspects regarding the recipient like informed consent and monitoring for ... | 2015 | 26408947 |
| ultrasensitive detection and subtyping of porcine endogenous retrovirus provirus based on magnetic nanoparticles and chemiluminescence. | porcine endogenous retrovirus (perv) is commonly integrated in pig genomes, and could cause a cross-species infection by xenotransplantation. in this study, we developed a rapid and ultrasensitive approach for detection and subtyping of perv provirus based on magnetic nanoparticles (mnps) and chemiluminescence (cl). the carboxylated mnps (cmnps) were covalently coupled with aminated probes for capturing biotinylated target fragments of perv, the product of polymerase chain reaction (pcr). agaros ... | 2015 | 26369124 |
| distribution of porcine endogenous retrovirus in different organs of the hybrid of a landrace and a jeju domestic pig in korea. | xenotransplantation offers a solution to the shortage of available organs for transplantation, and the pig represents an ideal source of such organs. however, porcine endogenous retrovirus (perv), whose genome is integrated in pigs, has been suggested to pose a potential risk of xenotransmission. expression of pervs in different organs of pigs was carefully measured at dna, mrna, and protein levels, providing information valuable for the application of pig organs in xenotransplantation. an analy ... | 2015 | 26293098 |
| tolerance and immune response to the porcine endogenous retrovirus in german landrace pigs immunised with viral proteins. | immunisation of goats, mice, rats, rabbits, guinea pigs, and hamsters with the recombinant ectodomain of the porcine endogenous retrovirus (perv) transmembrane envelope (tm) protein (p15e) induced binding and neutralising immune antibodies in all animals. in contrast, no antibodies were induced when pigs were immunised with p15e, indicating that pigs are tolerant to their endogenous retroviruses, at least to the tm protein. to answer the question of whether pigs are tolerant to other structural ... | 2015 | 26043980 |
| differential sensitivity of porcine endogenous retrovirus to apobec3-mediated inhibition. | pigs are considered to be suitable xenotransplantation organ donors. however, the risk of pathogen transmission from pigs to humans is a major concern in the transplantation of porcine tissues. the porcine endogenous retroviruses (pervs) perv-a, perv-a/c, and perv-b can infect human cells, but perv-c is an ecotropic virus infecting only pig cells. thus, several strategies have been proposed to reduce perv transmission in xenograft recipients. human apobec3g (hua3g) is a single-strand dna cytosin ... | 2015 | 26016442 |
| xenotransplantation literature update, march-april 2015. | | 2015 | 25988427 |
| identification of porcine endogenous retrovirus (perv) packaging sequence and development of perv packaging viral vector system. | studies of the retroviruses have focused on the specific interaction of the nucleocapsid protein with a packaging signal in the viral rna as important for this selectivity, but the packaging signal in porcine endogenous retrovirus (perv) has not been defined. herein, we identified and analyzed this packaging signal in perv and found hairpin structures with conserved tetranucleotides in their loops and nucleocapsid recognition sequences; both of which are key elements in the viral packaging signa ... | 2015 | 25935307 |
| cytotoxic effects during knock out of multiple porcine endogenous retrovirus (perv) sequences in the pig genome by zinc finger nucleases (zfn). | xenotransplantation has been proposed as a solution to the shortage of suitable human donors for transplantation and pigs are currently favoured as donor animals. however, xenotransplantation may be associated with the transmission of zoonotic microorganisms. whereas most porcine microorganisms representing a risk for the human recipient may be eliminated by designated pathogen free breeding, multiple copies of porcine endogenous retroviruses (pervs) are integrated in the genome of all pigs and ... | 2015 | 25909512 |
| review on porcine endogenous retrovirus detection assays--impact on quality and safety of xenotransplants. | xenotransplantation of porcine organs, tissues, and cells inherits a risk for xenozoonotic infections. viable tissues and cells intended for transplantation have to be considered as potentially contaminated non-sterile products. the demands on microbial testing, based on the regulatory requirements, are often challenging due to a restricted shelf life or the complexity of the product itself. in europe, the regulatory framework for xenogeneic cell therapy is based on the advanced therapy medicina ... | 2015 | 25641488 |
| porcine endogenous retrovirus infection of human peripheral blood mononuclear cells. | | 2015 | 25511997 |
| clinical porcine islet xenotransplantation under comprehensive regulation. | xenotransplantation with porcine islets is a promising approach to overcome the shortage of human donors. this is the first report of phase 1/2a xenotransplantation study of encapsulated neonatal porcine islets under the current framework of regulations for xenotransplantation in new zealand. | 2014 | 25131091 |
| microarray analysis of retroviral restriction factor gene expression in response to porcine endogenous retrovirus infection. | microarray analysis has been used for screening genes involved in specific biological processes. many studies have shown that restriction factors may play an important role in xenotransplantation safety, but it is still unclear whether porcine endogenous retroviruses (pervs) may be inhibited by these factors. therefore, the present study focused on the microarray analysis retroviral restriction factors gene expression in normal human dermal fibroblasts (nhdfs) in response to pervs. perv infectiv ... | 2014 | 25115112 |
| differential expression of tripartite motif-containing family in normal human dermal fibroblasts in response to porcine endogenous retrovirus infection. | antiretroviral restriction factors may play an essential role in the safety of xenotransplantation. therefore, the present study focused on investigation of the changes in the tripartite motif-containing family (trim) gene expression in normal human dermal fibroblasts with and without lipopolysaccharide stimulation in response to porcine endogenous retrovirus infection. analysis of the expression profile of trims was performed using oligonucleotide microarrays and qrt-pcr. nine (trim1, trim2, tr ... | 2014 | 25056437 |