Endogenous retroviruses

On the other hand, EFN-a may also be involved in the activation of autoreactive T-cells as has been proposed for type I diabetes. An DFN-a inducible superantigen, encoded by the truncated envelope gene of a human endogenous retrovirus and specifically activating V 37 T-cells, has been detected in pancreatic lesions from type I diabetes patients, infiltrated by V 37 T-cells. Since IFN-a expression could be detected in pancreatic (3 cells in conceit with persistent viral infections, there is a clear link between viral infections and autoimmunity via IFN-a-stimulated superantigen expression. 

Human genome Nucleic acid sequences representing endogenous retroviruses are com-... 

Epstein-Barr virus/human endogenous retrovirus HERV-K18... 

Blond, J.-L., Lavillette, D., Cheynet, V., Bouton, 0., Oriol, G., Chapel-Fernandes, S., Mandrand, B., Mallet, F. and Cosset, F.-L. (2000) An envelope glycoprotein of the human endogenous retrovirus HERV-W is expressed in the human placenta and fuses cells expresing the type-D mammalian retrovirus receptor. J VirolU, 3321-3329. 

Lavillette, D., Marin, M., Ruggierei, A., Mallet, F., Cosset, F.-L. and Kahat, D. (2002) The envelope glycoprotein of human endogenous retrovirus type W uses a divergent family of amino acid transporters / cell surface receptors. J Viroll, 6442-6452. 

There have already been clinical trials of porcine hepatocyte-based bioartificial livers [5, 6]. However, we believe these systems to represent temporary and short-lived approaches. Compelling evidence from recent experiments show that primary porcine liver cells express and release endogenous retroviral particles that are able to infect human cells. However, long term in vivo investigations of patients previously exposed to porcine tissues over a period of 12 year did not show any porcine endogenous retrovirus (PERV) viremia [7]. Therefore, we consider the further pursuit of porcine bioartificial livers the only solution at present with regard to the cell source. However, as an intermediate term alternative human cell sources are in development [8]. Expansion technologies for human fetal cells may contribute to resolve these limitations in the future. 

A further study was conducted to examine the expression and behaviour of endogenous retroviruses in these strains during the preleukaemic phase of butadiene exposure. Chronic exposure of B6C3Fj mice to butadiene (1250 ppm [2760 mg/m ]) for 6 h per day on five days per week for 3-21 weeks increased markedly the quantity of ecotropic retrovirus recoverable from the bone marrow, thymus and spleen. Expression of other endogenous retroviruses (xenotropic, MCF-ERV) was not enhanced. No virus of any type was found in similarly treated NIH Swiss mice (Irons et al., 1987a). 

Bromham, L. (2002) The human zoo endogenous retroviruses in the human genome. Trends Ecol. Evolut. 17, 91-97. 

Viruses. Rabbits have been induced to produce anti-RNP antibodies by immunization with the p30 gag protein, a protein of several mammalian C-type viruses (Ql). Blomberg et al. found an increased frequency of antibodies that were cross-reactive with baboon endogenous retrovirus and murine leukemia virus among 72 SLE patients compared with 88 controls (B17). Plotz found that autoantibodies in patients with lupus are antiidiotype antibodies to antiviral antibodies (P4). 

Animal models of disease, whether naturally occurring or artificially induced, provide valuable insights into human disease and allow rigidly controlled studies that are not possible in humans. Probably the most intensively studied model of an immune complex disease is the spontaneous lupuslike disease that occurs in certain inbred strains of mice, especially the (NZB x NZW) F, hybrid. Its study has provided insights with respect to genetic predisposition (H25), the role of endogenous retroviruses (D8), the influence of sex hormones (R9), the identification of T suppressor cell abnormalities (T3), and the propensity to form certain autoantibodies, especially to double-stranded DNA (S36) and to the RNA-protein complex, Sm (E2). Though animal studies are not the subject of this review, we emphasize that the entire concept and framework by which we view immune complex disease in humans are based on initial observations in animals. 

Hadlock KG, Miller RG, Jin X, Yu S, Reis J, Mass J, Gelinas DF, McGrath MS (2004) Elevated rates of antibody reactivity to HML-2/Herv-K but not other endogenous retroviruses in ALS. 56th annual meeting of the American Academy of Neurology, San Francisco, CA. 

Major concerns in the use of retroviral vectors are the possibility of vector mobilization and recombination with defective (endogenous) retroviruses in the target cell. This led to the development of self-inactivating vectors (SIN) (38). In these vectors, the viral promotor and enhancer regions in the 3 U3 are deleted, thus preventing LTR-driven transcription in the transduced cells. Furthermore, transgene expression in these vectors is exclusively driven by an internal promotor, which improves the use of regulatory and tissue-specific promoters. 

Hsieh, L. L., Shinozuka, H., and Weinstein, 1. B. (1991). Changes in expression of cellular oncogenes and endogenous retrovirus-Uke sequences during hepatocarcincgenesis induced by a peroxisome proliferator. Br J Cancer 64, 815-820. 

Systemic sclerosis Parvovirus B19, cytomegalovirus, Epstein-Barr virus, endogenous retrovirus, Helicobacter pylori... 

Magistrelli C, Samoilova E, Agarwal RK, Banki K, Ferrante P, Vladutiu A, Phillips PE, Perl A (1999) Polymorphic genotypes of the HRES-1 human endogenous retrovirus locus correlate with systemic lupus erythematosus and autoreactivity. Immunogenetics, 49 829-834. 

The most common sources of impurities are derived from the fermentation process and would include such factors as host cell protein or DNA, or components from cell culture growth media. In addition, endogenous retroviruses from hybrido-mas in monoclonal antibody production can also be present as impurities, all of which should be removed and tested for in the final product. [1], These impurities can be present as lipopolysaccharides, oligonucleotides, and leachates from containers. The most common tests that are conducted for the reference standard and production batches are shown in Table 9.2. 

PCR polymerase chain reaction PERV porcine endogenous retrovirus SCID severe combined immunodeficiency... 

Blusch JH, Patience C, Martin U. Pig endogenous retroviruses and xenotransplantation. Xenotransplantation 2002 9(4) 242-251. 

Polymerase chain reaction (PCR)-based assays amplify a specific target DNA which can be used in a variety of analytical applications. Quantitative PCR has been used for lot release testing, the detection of viral contaminants (both in raw material testing as well as in-process control), the quantification of endogenous retroviruses in cell cultures, host cell DNA quantification, and the determination of genetic stability in cell lines [13-15]. 

Poly(lactide-co-glycolide), for peptide Porcine endogenous retrovirus (PERV) 369... 

Virus loads in unprocessed, prepurified bulk (harvest samples) are quantified, typically via transmission by electron microscopy or infectivity, to estimate actual virus load versus the expected virus removal capacity of the process [47,50]. Total virus clearance should exceed measured levels by at least 3-5 logs [47]. An example of a typical virus load is 10 to 10 RVLPs (retrovirus-like particles) per milliliter of unprocessed bulk from CHO cells [3]. Clearance factors of 15-20 logs are typical for murine retroviruses [3] and slightly more than for lipid-enveloped viruses. For most viruses besides endogenous retroviruses, however, there is no reasonable way to establish virus load in the bulk because these types of viruses should not normally be present. In addition direct testing methods are limited inherently because they are designed to detect only known and not known contaminants [5]. Thus, the... 

ELISA 108 Embryonenschutz 249 EMEA 41, 98, 123, 201, 243 annual report 204 210-day window 205 legislation 201 organizational stmcture 207 endocytosis 155 endogenous retrovirus 275 endoplasmatic reticulum 45 endothelial cell activation 273 endotoxin 54, 104, 140, 244 engerix 127 engerix-B 134 engineered tissues ... 

Hume This actually happens in the sense that one of the outputs of the RIKEN project which we haven t come to grips with is that endogenous retroviruses are also tissue-specifically transcribed. They are also strain specific. Some of the... 

Young The endogenous retrovirus is hard to exclude. The others can be excluded by the fact that in different animal houses people get the same data with the same strains of mice. 

---