@article{LindemannRethwilm2011, author = {Lindemann, Dirk and Rethwilm, Axel}, title = {Foamy Virus Biology and Its Application for Vector Development}, series = {Viruses}, volume = {3}, journal = {Viruses}, number = {5}, doi = {10.3390/v3050561}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139811}, pages = {561-585}, year = {2011}, abstract = {Spuma- or foamy viruses (FV), endemic in most non-human primates, cats, cattle and horses, comprise a special type of retrovirus that has developed a replication strategy combining features of both retroviruses and hepadnaviruses. Unique features of FVs include an apparent apathogenicity in natural hosts as well as zoonotically infected humans, a reverse transcription of the packaged viral RNA genome late during viral replication resulting in an infectious DNA genome in released FV particles and a special particle release strategy depending capsid and glycoprotein coexpression and specific interaction between both components. In addition, particular features with respect to the integration profile into the host genomic DNA discriminate FV from orthoretroviruses. It appears that some inherent properties of FV vectors set them favorably apart from orthoretroviral vectors and ask for additional basic research on the viruses as well as on the application in Gene Therapy. This review will summarize the current knowledge of FV biology and the development as a gene transfer system.}, language = {en} } @article{BaunachMaurerHahnetal.1993, author = {Baunach, Gerald and Maurer, Bernd and Hahn, Heidi and Kranz, Manuela and Rethwilm, Axel}, title = {Functional analysis of human foamy virus accessory reading frames}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61398}, year = {1993}, abstract = {No abstract available}, subject = {Virologie}, language = {en} } @article{KasangKalluvyaMajingeetal.2011, author = {Kasang, Christa and Kalluvya, Samuel and Majinge, Charles and Stich, August and Bodem, Jochen and Kongola, Gilbert and Jacobs, Graeme B. and Mllewa, Mathias and Mildner, Miriam and Hensel, Irina and Horn, Anne and Preiser, Wolfgang and van Zyl, Gert and Klinker, Hartwig and Koutsilieri, Eleni and Rethwilm, Axel and Scheller, Carsten and Weissbrich, Benedikt}, title = {HIV drug resistance (HIVDR) in antiretroviral therapy-naive patients in Tanzania not eligible for WHO threshold HIVDR survey is dramatically high}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69024}, year = {2011}, abstract = {Background: The World Health Organization (WHO) has recommended guidelines for a HIV drug resistance (HIVDR) survey for resource-limited countries. Eligibility criteria for patients include age below 25 years in order to focus on the prevalence of transmitted HIVDR (tHIVDR) in newly-infected individuals. Most of the participating sites across Africa have so far reported tHIVDR prevalences of below 5\%. In this study we investigated whether the rate of HIVDR in patients ,25 years is representative for HIVDR in the rest of the therapy-naive population. Methods and Findings: HIVDR was determined in 88 sequentially enrolled ART-naive patients from Mwanza, Tanzania (mean age 35.4 years). Twenty patients were aged, 25 years and 68 patients were aged 25-63 years. The frequency of HIVDR in the study population was 14.8\% (95\%; CI 0.072-0.223) and independent of NVP-resistance induced by prevention of mother-to-child transmission programs. Patients .25 years had a significantly higher HIVDR frequency than younger patients (19.1\%; 95\% CI 0.095-0.28) versus 0\%, P = 0.0344). In 2 out of the 16 patients with HIVDR we found traces of antiretrovirals (ARVs) in plasma. Conclusions: ART-naive patients aged over 25 years exhibited significantly higher HIVDR than younger patients. Detection of traces of ARVs in individuals with HIVDR suggests that besides transmission, undisclosed misuse of ARVs may constitute a significant factor in the generation of the observed high HIVDR rate. The current WHO tHIVDR survey that is solely focused on the transmission of HIVDR and that excludes patients over 25 years of age may therefore result in substantial underestimation of the prevalence of HIVDR in the therapy-naive population. Similar studies should be performed also in other areas to test whether the so far reported optimistic picture of low HIVDR prevalence in young individuals is really representative for the rest of the ART-naive HIV-infected population.}, subject = {Tansania}, language = {en} } @article{KasangKalluvyaMajingeetal.2011, author = {Kasang, Christa and Kalluvya, Samuel and Majinge, Charles and Stich, August and Bodem, Jochen and Kongola, Gilbert and Jacobs, Graeme B. and Mlewa, Mathias and Mildner, Miriam and Hensel, Irina and Horn, Anne and Preiser, Wolfgang and van Zyl, Gert and Klinker, Hartwig and Koutsilieri, Eleni and Rethwilm, Axel and Scheller, Carsten and Weissbrich, Benedikt}, title = {HIV Drug Resistance (HIVDR) in Antiretroviral Therapy-Na{\"i}ve Patients in Tanzania Not Eligible for WHO Threshold HIVDR Survey Is Dramatically High}, series = {PLoS One}, volume = {6}, journal = {PLoS One}, number = {8}, doi = {10.1371/journal.pone.0023091}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137988}, pages = {e23091}, year = {2011}, abstract = {Background The World Health Organization (WHO) has recommended guidelines for a HIV drug resistance (HIVDR) survey for resource-limited countries. Eligibility criteria for patients include age below 25 years in order to focus on the prevalence of transmitted HIVDR (tHIVDR) in newly-infected individuals. Most of the participating sites across Africa have so far reported tHIVDR prevalences of below 5\%. In this study we investigated whether the rate of HIVDR in patients <25 years is representative for HIVDR in the rest of the therapy-na{\"i}ve population. Methods and Findings HIVDR was determined in 88 sequentially enrolled ART-na{\"i}ve patients from Mwanza, Tanzania (mean age 35.4 years). Twenty patients were aged <25 years and 68 patients were aged 25-63 years. The frequency of HIVDR in the study population was 14.8\% (95\%; CI 0.072-0.223) and independent of NVP-resistance induced by prevention of mother-to-child transmission programs. Patients >25 years had a significantly higher HIVDR frequency than younger patients (19.1\%; 95\% CI 0.095-0.28) versus 0\%, P = 0.0344). In 2 out of the 16 patients with HIVDR we found traces of antiretrovirals (ARVs) in plasma. Conclusions ART-na{\"i}ve patients aged over 25 years exhibited significantly higher HIVDR than younger patients. Detection of traces of ARVs in individuals with HIVDR suggests that besides transmission, undisclosed misuse of ARVs may constitute a significant factor in the generation of the observed high HIVDR rate. The current WHO tHIVDR survey that is solely focused on the transmission of HIVDR and that excludes patients over 25 years of age may therefore result in substantial underestimation of the prevalence of HIVDR in the therapy-na{\"i}ve population. Similar studies should be performed also in other areas to test whether the so far reported optimistic picture of low HIVDR prevalence in young individuals is really representative for the rest of the ART-na{\"i}ve HIV-infected population.}, language = {en} } @article{KasangUlmerDonhauseretal.2012, author = {Kasang, Christa and Ulmer, Albrecht and Donhauser, Norbert and Schmidt, Barabara and Stich, August and Klinker, Hartwig and Kalluvya, Samuel and Koutsilieri, Eleni and Rethwilm, Axel and Scheller, Carsten}, title = {HIV patients treated with low-dose prednisolone exhibit lower immune activation than untreated patients}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75100}, year = {2012}, abstract = {Background: HIV-associated general immune activation is a strong predictor for HIV disease progression, suggesting that chronic immune activation may drive HIV pathogenesis. Consequently, immunomodulating agents may decelerate HIV disease progression. Methods: In an observational study, we determined immune activation in HIV patients receiving low-dose (5 mg/day) prednisolone with or without highly-active antiretroviral therapy (HAART) compared to patients without prednisolone treatment. Lymphocyte activation was determined by flow cytometry detecting expression of CD38 on CD8(+) T cells. The monocyte activation markers sCD14 and LPS binding protein (LBP) as well as inflammation markers soluble urokinase plasminogen activated receptor (suPAR) and sCD40L were determined from plasma by ELISA. Results: CD38-expression on CD8+ T lymphocytes was significantly lower in prednisolone-treated patients compared to untreated patients (median 55.40\% [percentile range 48.76-67.70] versus 73.34\% [65.21-78.92], p = 0.0011, Mann-Whitney test). Similarly, we detected lower levels of sCD14 (3.6 μg/ml [2.78-5.12] vs. 6.11 μg/ml [4.58-7.70]; p = 0.0048), LBP (2.18 ng/ml [1.59-2.87] vs. 3.45 ng/ml [1.84-5.03]; p = 0.0386), suPAR antigen (2.17 μg/ml [1.65-2.81] vs. 2.56 μg/ml [2.24-4.26]; p = 0.0351) and a trend towards lower levels of sCD40L (2.70 pg/ml [1.90-4.00] vs. 3.60 pg/ml [2.95-5.30]; p = 0.0782). Viral load in both groups was similar (0.8 × 105 ng/ml [0.2-42.4 × 105] vs. 1.1 × 105 [0.5-12.2 × 105]; p = 0.3806). No effects attributable to prednisolone were observed when patients receiving HAART in combination with prednisolone were compared to patients who received HAART alone. Conclusions: Patients treated with low-dose prednisolone display significantly lower general immune activation than untreated patients. Further longitudinal studies are required to assess whether treatment with low-dose prednisolone translates into differences in HIV disease progression.}, subject = {HIV}, language = {en} } @article{AguzziWagnerNetzeretal.1993, author = {Aguzzi, A. and Wagner, E. F. and Netzer, K. O. and Bothe, K. and Anhauser, I. and Rethwilm, Axel}, title = {Human foamy virus proteins accumulate in neurons and induce multinucleated giant cells in the brain of transgenic mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47356}, year = {1993}, abstract = {Humanfoamy virus (HFV) is a retrovirus encoding structural genes and, like human immunodeficiency virus and human T ceU leukemia virus I, several anciUary reading frames collectively termed the belgenes. We have previously shown that HFV transgenic mice develop an encephalopathy with neuronal loss in hippocampus and cerebral cortex. We have now raised and characterized rabbit antisera to various recombinant portions of gag, pot, env, and bel-I, the viraltransactivator. Immunoreactivity for gag and bel-I was observed in nuclei and processes of hippocampal and cortical neurons before the onset of morphological lesions and correlated with the appearance of HFV mRNA. Astrocyte-derived multinucleated giant ceUs containing HFV proteins were present in the brain oftransgenic mice coexpressingfuU- length HFV genes but not in mice expressing truncated gag and env, suggesting that these genes contain afusogenic domain. Expression of fuU-length structural genes decreased the life expectancy oftransgenic mice, implying an a4Juvant rolefor these proteins in HFV-induced brain damage. (Am] Pathol 1993, 142:1061-1072)}, subject = {Molekularpathologie}, language = {en} } @article{NetzerSchliephakeMaureretal.1993, author = {Netzer, Kai O. and Schliephake, Andreas and Maurer, Bernd and Watanabe, Rihito and Aguzzi, Adriano and Rethwilm, Axel}, title = {Identification of pol-related gene products of human foamy virus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61429}, year = {1993}, abstract = {Human foamy viruspol gene fragments were molecularly cloned into a procaryotic expression vector. The expression pattern of the cloned fragments and nucleotide sequence analysis of the 5' pol gene region revealed that in HFV the protease (PR) is located in the pol open reading frame. Purified recombinant proteins were used to generate antibodies in rats. ln immunoblot assay, using infected cells as antigen, a precursor protein with an apparent molecular mass (M,) of 127K was identified by antibodies directed against the reverse transcriptase (RT), RNaseH, or integrase (IN) domeins of pol. With concentrated virus as antigen, the RT and RNaseH antibodies recognized a protein of 80K, the IN antiserum recognized a protein of 40K, and the PR antiserum detected a protein of approximately 10K.}, subject = {Virologie}, language = {en} } @article{NetzerRethwilmMaureretal.1990, author = {Netzer, Kai O. and Rethwilm, Axel and Maurer, Bernd and ter Meulen, Volker}, title = {Identification of the major immunogenic structural proteins of human foamy virus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61477}, year = {1990}, abstract = {We have identified the major immunogenic structural proteins of the human foamy virus (HFV), a distinct member of the foamy virus subfamily of Retroviridae. Radiolabelied viral proteins were immunoprecipitated from HFV -infected cells by foamy virus antisera of human and non-human primate origin. Precipitated viral proteins were in the range of 31 K to 170K. Labelling of proteins with [\(^{14}\)C]glucosamine or with [\(^{35}\)S]methionine in the presence oftunicamycin, as well as endo-ß-N-acetylglycosaminidase Hand F treatment of [\(^{35}\)S]methionine-labelled proteins, revealed three viral glycoproteins of approximately 170K, 130K and 47K, most likely representing the env gene-encoded precursor, the surface glycoprotein and the transmembrane protein of HFV, respectively.}, subject = {Virologie}, language = {en} } @article{BrinkmannSchwinnMuelleretal.1993, author = {Brinkmann, R. and Schwinn, A. and M{\"u}ller, J. and Stahl-Hennig, C. and Coulibaly, C. and Hunsmann, G. and Czub, S. and Rethwilm, Axel and D{\"o}rries, R. and ter Meulen, Volker}, title = {In vitro and in vivo infection of rhesus monkey microglial cells by simian immunodeficiency virus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61415}, year = {1993}, abstract = {The observation that microglial cells in brain tissue are probably a major target for human immunodeficiency virus (HIV) infection has raised interest in the pathogenic role of this cell population for the development of neuro-AIOS. Since it is very difficult to obtain microglia from normal or diseased human brain we studied microglial cells isolated from fresh brain tissue of uninfected and simian immunodeficiency virus (SIV) infected rhesus monkeys (Macacca mulatta) in comparison to peripheral blood macrophages. Besides the characterization of the phenotypes of these two cell populations, we examined the replication of SIV in the cells in addition to the effect of viral infection on the expression of cell surface molecules. We found that microglia and macrophages support replication of the wild-type SIV\(_{mac25}\), strain as well as the infectious clone (SIV\(_239\)). Infectious viruswas produced and a CPE developed. Isolated microglial cells from SIV-infected monkeys were latently infected independent of the presence of neuropathological lesions and produced infectious virus after 20-25 days in culture. In situ hybridization revealed that only a small percentage of isolated microglial cells are productively infected in vivo, yet the majority of these expressed MHC class II molecules. This indicated a state of activation that is acquired in vivo. These findings indicate that microglia are a prime target cell for SIV infection in CNS tissue.}, subject = {Virologie}, language = {en} } @article{RethwilmBaunachNetzeretal.1990, author = {Rethwilm, Axel and Baunach, Gerald and Netzer, Kai O. and Maurer, Bernd and Borisch, Bettina and ter Meulen, V.olker}, title = {Infectious DNA of the human spumaretrovirus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61495}, year = {1990}, abstract = {An infectious molecular clone (pHSRV) of the human Spumaretrovirus (HSRV) was constructed using viral DNA and cDNA clones. The infectivity of pHSRV was proven by transfection of cell cultures and subsequent infection of susceptible cultures with cell free transfection derlved virus. pHSRV derived virus produced foamy virus typical cytopathic effects in susceptible cultures. lnfected cells could be stained specifically with foamy virus antisera by means of indirect immunofluorescence. Radiolmmunoprecipltatlon revealed the presence of characteristic HSRV structural proteins in pHSRV infected cultures. By cotransfection of pHSRV and an indicator plasmid it was found that pHSRV is able to transactivate the viral L TR. Viral transcripts were found to be approximately 200 bases Ionger in pHSRV infected cultures compared to wildtype infected cultures. This difference is most likely due to an Insertion of DNA of non-viral origin ln the U3 region of the 3'L TR of the infectious clone.}, subject = {Virologie}, language = {en} } @article{RethwilmDaraiRoesenetal.1987, author = {Rethwilm, Axel and Darai, G. and R{\"o}sen, A. and Maurer, Bernd and Fl{\"u}gel, Rolf M.}, title = {Molecular cloning of the genome of human spumaretrovirus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61518}, year = {1987}, abstract = {DNA ofhuman spumaretrovirus (HSRV) was cloned from both cDNA and from viral DNA into phage A and bacterial plasmid vectors. The recombinant plasm.ids harboring viral DNA were characterized by Southern blot hybridization and restriction mapping. Physical maps were constructed from cDNA and found to be colinear with the restriction maps obtained from viral DNA. The recombinant clones isolated contained viral DNA inserts which rangein size from 2.2 kb to 15.4 kb. The recombinant clones allowed to construct a physical map of the complete HSRV provirus of 12.2 kb.}, subject = {Virologie}, language = {en} } @article{KincaidChenCoxetal.2014, author = {Kincaid, Rodney P. and Chen, Yating and Cox, Jennifer E. and Rethwilm, Axel and Sullivan, Christopher S.}, title = {Noncanonical MicroRNA (miRNA) Biogenesis Gives Rise to Retroviral Mimics of Lymphoproliferative and Immunosuppressive Host miRNAs}, series = {mBio}, volume = {5}, journal = {mBio}, number = {2}, issn = {2150-7511}, doi = {10.1128/mBio.00074-14}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117216}, pages = {e00074-14}, year = {2014}, abstract = {MicroRNAs (miRNAs) play regulatory roles in diverse processes in both eukaryotic hosts and their viruses, yet fundamental questions remain about which viruses code for miRNAs and the functions that they serve. Simian foamy viruses (SFVs) of Old World monkeys and apes can zoonotically infect humans and, by ill-defined mechanisms, take up lifelong infections in their hosts. Here, we report that SFVs encode multiple miRNAs via a noncanonical mode of biogenesis. The primary SFV miRNA transcripts (pri-miRNAs) are transcribed by RNA polymerase III (RNAP III) and take multiple forms, including some that are cleaved by Drosha. However, these miRNAs are generated in a context-dependent fashion, as longer RNAP II transcripts spanning this region are resistant to Drosha cleavage. This suggests that the virus may avoid any fitness penalty that could be associated with viral genome/transcript cleavage. Two SFV miRNAs share sequence similarity and functionality with notable host miRNAs, the lymphoproliferative miRNA miR-155 and the innate immunity suppressor miR-132. These results have important implications regarding foamy virus biology, viral miRNAs, and the development of retroviral-based vectors. IMPORTANCE Fundamental questions remain about which viruses encode miRNAs and their associated functions. Currently, few natural viruses with RNA genomes have been reported to encode miRNAs. Simian foamy viruses are retroviruses that are prevalent in nonhuman host populations, and some can zoonotically infect humans who hunt primates or work as animal caretakers. We identify a cluster of miRNAs encoded by SFV. Characterization of these miRNAs reveals evolutionarily conserved, unconventional mechanisms to generate small RNAs. Several SFV miRNAs share sequence similarity and functionality with host miRNAs, including the oncogenic miRNA miR-155 and innate immunity suppressor miR-132. Strikingly, unrelated herpesviruses also tap into one or both of these same regulatory pathways, implying relevance to a broad range of viruses. These findings provide new insights with respect to foamy virus biology and vectorology.}, language = {en} } @article{SchliephakeRethwilm1994, author = {Schliephake, Andreas W. and Rethwilm, Axel}, title = {Nuclear Localization of Foamy Virus Gag Precursor Protein}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61371}, year = {1994}, abstract = {All foamy viruses give rise to a strong nuclear staining when infected cells are reacted with sera from infected hosts. This nuclear ftuorescence distinguishes foamy viruses from all other retroviruses. The experiments reported here indicate that the foamy virus Gag precursor protein is transiently located in the nuclei of infected cells and this is the likely reason for the typical foamy virus nuclear fluorescence. By using the vaccinia virus expression system, a conserved basic sequence motif in the nucleocapsid domain of foamy virus Cag proteins was identified to be responsible for the nuclear transport of the gag precursor molecule. Tbis motif was also found to be able to direct a heterologous protein, the Gag protein of human immunodeficiency virus, into the nucleus.}, subject = {Virologie}, language = {en} } @article{FluegelMaurerBannertetal.1987, author = {Fl{\"u}gel, Rolf M. and Maurer, Bernd and Bannert, Helmut and Rethwilm, Axel and Schnitzler, Paul and Darai, Gholamreza}, title = {Nucleotide sequence analysis of a cloned DNA fragment from human cells reveals homology to retrotransposons}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61525}, year = {1987}, abstract = {During molecular cloning of proviral DNA of human. spumaretroVirus, various recombinant clones were estabUshed and analyzed. Blot hybridization revealed that one of the recoinbinant plasmids bad the characteristic features of a member of the long interspersed repetitive sequences famlly. The DNA element was analyzed by restrictioil mapping and nuelootide sequencing. It showed a high degree of amino acid sequence homology of 54.3\% when conipared with the 5'-terminal part of the pol gelie product of the murine retrotransposon LIMd. The 3' region of the cloned DNA element encodes proteins witb an even higher degree of homology of 67.4\% in comparison to the corresponding parts of a member of the primate Kpnl sequence family.}, subject = {Virologie}, language = {en} } @article{FluegelRethwilmMaureretal.1987, author = {Fl{\"u}gel, Rolf M. and Rethwilm, Axel and Maurer, Bernd and Darai, Gholamreza}, title = {Nucleotide sequence analysis of the env gene and its flanking regions of the human spumaretrovirus reveals two novel genes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61509}, year = {1987}, abstract = {Recombinant clonesthat represent the 3' part ofthe genome of the human spumaretrovirus (foamy virus) were established from viral DNA and from DNA complementary to viral RNA. The recombinant clones were characterized by blot hybridizations and nucleotide sequence analysis. The deduced protein sequence of the clones at their 5' ends was found to be homologous to the 3' domain of retroviral reverse transcriptases. Downstream of a small intergerne pol-env region a long open reading frame of 985 amino acid residues was identified that according to its genomic location, size, glycosylation signals, and hydrophobicity protile closely resembles the lentiviral env genes. The spumaretroviral env gene is followed by two open reading frames, termed bel-l and bel-2 which are located between env and the long terminal repeat region. The long terminal repeat of 1259 nucleotides is preceded by a polypurine tract and contains the canonical signal sequences characteristic for transcriptional regulation of retroviruses. The provisional classitication of the spumaretrovirus subfamily is discussed.}, subject = {Virologie}, language = {en} } @article{BotheAguzziLassmannetal.1991, author = {Bothe, Katrin and Aguzzi, Adriano and Lassmann, Hans and Rethwilm, Axel and Horak, Ivan}, title = {Progressive encephalopathy and myopathy in transgenic mice expressing human foamy virus genes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61453}, year = {1991}, abstract = {Transgenie mice carrying the bel region of human foamy retrovirus (HFV) under transcriptional control of its own long terminal repeat expressed tbe transgene in their centrat nervous systems and in smootb and striated muscle tissues. The animals developed a progressive degenerative disease of tbe centrat nervous system and of the striated muscle. Because expression of tbe transgene was dosely correlated witb the appearance of structural damage and inflammatory reactions were scanty, the disease is likely to be caused directly by tbe HFV proteins. These unexpected findings call for a reevaluation of tbe patbogenic potential of HFV in humans.}, subject = {Virologie}, language = {en} } @article{HahnBaunachBraeutigametal.1994, author = {Hahn, Heidi and Baunach, Gerald and Br{\"a}utigam, Sandra and Mergia, Ayalew and Neumann-Haefelin, Dieter and Daniel, Muthiah D. and McClure, Myra O. and Rethwilm, Axel}, title = {Reactivity of primate sera to foamy virus Gag and Bet proteins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61366}, year = {1994}, abstract = {In order to establish criteria for the Serodiagnosis of foamy virus infections we investigated the extent to which sera from iofected individuals of human and primate origin react with structural and non-structural virus proteins in immunoblot assays. Using lysates from infected cells as the source of virus antigen, antibodies were preferentially detected against the Gag proteins and the non-structural Bet protein. Both the Gag precursor molecules of 70 and 74K apparent M\(_r\) and the cytoplasmic 60K M\(_r\) Bet protein were found to be phosphorylated, the latter being synthesized in large amounts in infected cells. Rahbit antiserum raised against recombinant human foamy virus (HFV) Gag major capsid protein cross-reacted with foamy viruses of chimpanzee, gorilla, orang-utan, rhesus monkey and Mrican green monkey origin. This was reßected by a broad cross-reactivity of the respective monkey sera to the Gag proteins of the various foamy virus isolates. Cross-reactivity of antisera against the Bet protein was restricted to viruses from man and the great apes. Recombinant Gag and Bet proteins expressed in prokaryotes or in insect cells were readily recognized by foamy virus-positive primate sera. Screening serum samples from chimpanzees with HFV Gag and Bet proteins expressed by recombinant baculoviruses revealed that 18 out of 35 (52\%) were positive for Gag antibodies. Of these, 13 (72 o/o) showed antiborlies against the Bet protein, indicating that Bet antigen is of value in sero1ogical screening for foamy virus infections.}, subject = {Virologie}, language = {en} } @article{HartlBodemJochheimetal.2011, author = {Hartl, Maximilian J. and Bodem, Jochen and Jochheim, Fabian and Rethwilm, Axel and R{\"o}sch, Paul and W{\"o}hrl, Birgitta M.}, title = {Regulation of foamy virus protease activity by viral RNA}, series = {Retrovirology}, volume = {8}, journal = {Retrovirology}, number = {Suppl. 1}, doi = {10.1186/1742-4690-8-S1-A228}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-142248}, pages = {A228}, year = {2011}, abstract = {No abstract available.}, language = {en} } @inproceedings{MoriRethwilmSchwinnetal.1990, author = {Mori, Kazuyasu and Rethwilm, Axel and Schwinn, Andreas and Horak, Ivan}, title = {Replication of human immunodeficiency virus type 1 in human t-cells expressing antisense RNA}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86426}, year = {1990}, abstract = {No abstract available.}, subject = {HIV}, language = {en} } @article{JocherRethwilmKapposetal.1990, author = {Jocher, R. and Rethwilm, Axel and Kappos, L. and ter Meulen, Volker}, title = {Search for retroviral sequences in peripheral blood mononuclear cells and brain tissue of multiple sclerosis patients}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61462}, year = {1990}, abstract = {DNAs from peripheral blood mononuclear cells (PBMCs) of 21 patients with multiple sclerosis (MS), 1 patient with tropical spastic paraparesis (TSP) as well as DNAs from brain and spinal cord of 5 MS cases and 3 controls were examined for human T-cell lymphotropic virus (HTLV)-related sequences by polymerase chain reaction. The primers used were derived from the HTLV-1 gag, env and tax genes. Amplified products were separated on agarase gels, blotted onto nylon membranes and hybridized to specific radiolabelled oligonucleotides. The sensitivity of amplification and hybridization was one copy of target DNA in 10\8^5\) cellular genomes. None of the specimens was positive for HTLV-1 sequences except the TSP probe. These negative data are all the more significant because brain -material from MS patients was used in these studies. Our studies thus fail to support speculations that HTLV-I is involved in the aetiology of multiple sclerosis.}, subject = {Virologie}, language = {en} } @article{GowSimpsonSchliephakeetal.1992, author = {Gow, J. W. and Simpson, K. and Schliephake, Andreas and Behan, W. M. and Morrison, L. J. and Cavanagh, H. and Rethwilm, Axel and Behan, P. O.}, title = {Search for retrovirus in the chronic fatigue syndrome}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61436}, year = {1992}, abstract = {Aim: To examine peripheral blood and skeletal muscle from patients with chronic fadgue syndrome for exogenous retrovirus. Methods: Blood samples from 30 patients and muscle biopsy specimens of 15 patients were examined for retroviral sequences by DNA extraction, polymerase chain reacdon (PCR), and Southern blotting hybridisation. Sera were examined for human foamy virus by western immunoblotting and indirect immunofluorescence techniques. Results: No difference between the padent and control populations was found for any of the PCR primer sets used (gag, pol, env, and tax regions of HTLV VII). An endogenous gag band was observed in both the padent and control groups. All sera were negative for antibody to human foamy virus. Conclusion: The results indicate that there is no evidence of retroviral involvement in the chronic fatigue syndrome.}, subject = {Virologie}, language = {en} } @article{SpannausHartlWoehrletal.2012, author = {Spannaus, Ralf and Hartl, Maximilian J. and W{\"o}hrl, Birgitta M. and Rethwilm, Axel and Bodem, Jochen}, title = {The prototype foamy virus protease is active independently of the integrase domain}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75370}, year = {2012}, abstract = {Background: Recently, contradictory results on foamy virus protease activity were published. While our own results indicated that protease activity is regulated by the viral RNA, others suggested that the integrase is involved in the regulation of the protease. Results: To solve this discrepancy we performed additional experiments showing that the protease-reverse transcriptase (PR-RT) exhibits protease activity in vitro and in vivo, which is independent of the integrase domain. In contrast, Pol incorporation, and therefore PR activity in the viral context, is dependent on the integrase domain. To further analyse the regulation of the protease, we incorporated Pol in viruses by expressing a GagPol fusion protein, which supported near wild-type like infectivity. A GagPR-RT fusion, lacking the integrase domain, also resulted in wild-type like Gag processing, indicating that the integrase is dispensable for viral Gag maturation. Furthermore, we demonstrate with a trans-complementation assays that the PR in the context of the PR-RT protein supports in trans both, viral maturation and infectivity. Conclusion: We provide evidence that the FV integrase is required for Pol encapsidation and that the FV PR activity is integrase independent. We show that an active PR can be encapsidated in trans as a GagPR-RT fusion protein.}, subject = {Medizin}, language = {en} } @article{MuellerKrennCzubetal.1993, author = {M{\"u}ller, J. and Krenn, V. and Czub, S. and Schindler, C. and Kneitz, C. and Kerkau, T. and Stahl-Henning, C. and Coulibaly, C. and Hunsmann, G. and Rethwilm, Axel and ter Meulen, Volker and M{\"u}ller-Hermelink, H. K.}, title = {The thymus in SIV infection}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-80265}, year = {1993}, abstract = {no abstract available}, subject = {HIV-Infektion}, language = {en} } @article{RethwilmErlweinBaunachetal.1991, author = {Rethwilm, Axel and Erlwein, Otto and Baunach, Gerald and Mauerer, Bernd and ter Meulen, Volker}, title = {The transcriptional transactivator of human foamy virus maps to the bel 1 genomic region}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47342}, year = {1991}, abstract = {The human foamy virus (HFV) genome possesses three open reading frames (bel I, 2, and 3) located between env and the 3' long terminal repeat. By analogy to other human retroviruses this region was selected as the most Iikely candidate to encode the viral transactivator. ResuIts presented here confirmed this and showed further that a deletion introduced only into the bell open reading frame of a plasmid derived from an infectious molecular clone of HFV abolished transactivation. In contrast, deletions in bel 2 and bel 3 had only minor effects on the ability to transactivate. The role of the bel I genomic region as a transactivator was further investigated by eukaryotic expression of a genome fragment of HFV spanning the bel I open reading frame. A construct expressing bell under control of a heterologous promoter was found to transactivate the HFV long terminal repeat in a dose-dependent fashion. Furthermore, it is shown that the U3 region of the HFV long terminal repeat is sufficient to respond to the HFV transactivator.}, subject = {Virologie}, language = {en} } @article{RethwilmMoriMaureretal.1990, author = {Rethwilm, Axel and Mori, Kazuyasu and Maurer, Bernd and ter Meulen, Volker}, title = {Transacting transcriptional activation of human spumaretrovirus LTR in infected cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61488}, year = {1990}, abstract = {The long terminal repeat (LTR) of the human spumaretrovirus (HSRV) was examined with respect to its ability to function as transcriptional promotor in virus-infected and uninfected cells. Transient transfections using a plasmid in which the 3' L TR of HSRV was coupled to the bacterial chloramphenicol cetyltransferase (cat) gene revealed that the Ievei of HSRV LTR-directed cat gene expression was markedly increased in HSRV-infected cells compared to uninfected cells. Northern blot analysis of cat mRNA from transfected cultures suggests that transactivation of HSRVdirected gene expression occurs at the transcriptionallevel.}, subject = {Virologie}, language = {en} } @inproceedings{RethwilmBaunachMorietal.1990, author = {Rethwilm, Axel and Baunach, Gerald and Mori, Kazuyasu and ter Meulen, Volker}, title = {Transactivation of HIV by human spumaretrovirus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86436}, year = {1990}, abstract = {To study the activation of HIV by human spumaretrovirus (HSRV) the long terminal repeats (LTRs) of HSRV, HIVl and HIV2 were examined with respect to their ability to function as transcriptional promoters in virus infected and uninfected cells. Transient transfections using plasmids in which the L TRs of the three viruses were coupled to the bacterial chloramphenicol acetyltransferase (CA T) gene revealed (i) the level of cat gene expression directed by the HSRV LTR was markedly increased in HSRV infected cells compared to uninfected cells, (ii) cat gene expression driven by the HIV1 LTR, but not by the HIV2 LTR could be enhanced upon HSRV infection, whereas (iii) neither in HIV1 nor in HIV2 infected cells an effect on HSRV LTR driven cat geneexpression was detected.}, subject = {HIV}, language = {en} } @article{MaurerSerflingterMeulenetal.1991, author = {Maurer, Bernd and Serfling, Edgar and ter Meulen, Volker and Rethwilm, Axel}, title = {Transcription factor AP-1 modulates the activity of the human foamy virus long terminal repeat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61444}, year = {1991}, abstract = {The human foamy virus (HFV) contains within the UJ region of its long terminal repeat (L TR) three perfect consensus sequences for the binding of the inducible transcription factor AP-1. Results of DNase I footprint protection and gel retardation assays demonstrated that proteins in extracts of HeLa and BHK-21 cells as weil as bacterially expressed Jun and Fos proteins bind to these AP-1 sites. By conducting transient expression assays using chloramphenicol acetyltransferase plasmids carrying LTR sequences with point-mutated AP-1 sites it was found that the three AP-1 sites contribute to the optimal activity ofthe HFV promoter. It is shown that lnduction of the HFV L TR by 12-O-tetradecanoylphorbol-13-acetate (TPA) and serum factors is mediated through the AP-1 sites.}, subject = {Virologie}, language = {en} } @article{SiwkaSchwinnBaczkoetal.1994, author = {Siwka, Wieslaw and Schwinn, Andreas and Baczko, Knut and Pardowitz, Iancu and Mhalu, Fred and Shao, John and Rethwilm, Axel and ter Meulen, Volker}, title = {vpu and env sequence variability of HIV-1 isolates from Tanzania}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61355}, year = {1994}, abstract = {No abstract available}, subject = {Virologie}, language = {en} }