@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} } @article{HongBraeutigamRethwilm1993, author = {Hong, Liu and Br{\"a}utigam, Sandra and Rethwilm, Axel}, title = {Expression of the human foamy virus bel-1 transactivator in insect cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61383}, year = {1993}, abstract = {The human foamy virus (HFV) bel-l transactivator protein was expressed in insect cells by a recombinant baculovirus. For the generation of the recombinant baculovirus, Acbel-1, the bel-l gene of an HFV mutant was used, that bears truncations in the bel-l overlapping bel-2 open reading frame. Acbel-1 infected Sf9 cells produced high amounts of recombinant protein of the same electrophoretic mobility (36 kD) as bel-l expressed in mammalian cells. The baculovirus expressed bel-l proteinwas readily identified by a polyclonal rabbit serum directed against bel-1 in immunoblot assay. As in mammalian cells, bel-l was predominantly localized to the nucleus of Acbel-1 infected insect cells. The baculovirus expressed bel-1 proteinwill be of use to determine the action of this novel viral transactivator more precisely.}, subject = {Virologie}, language = {en} } @article{JacobsBockSchuchetal.2012, author = {Jacobs, Graeme and Bock, Stefanie and Schuch, Anita and Moschall, Rebecca and Schrom, Eva-Maria and Zahn, Juliane and Reuter, Christian and Preiser, Wolfgang and Rethwilm, Axel and Engelbrecht, Susan and Krekau, Thomas and Bodem, Jochen}, title = {Construction of a high titer Infectious HIV-1 subtype C proviral clone from South Africa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76340}, year = {2012}, abstract = {The Human Immunodeficiency Virus type 1 (HIV-1) subtype C is currently the predominant subtype worldwide. Cell culture studies of Sub-Saharan African subtype C proviral plasmids are hampered by the low replication capacity of the resulting viruses, although viral loads in subtype C infected patients are as high as those from patients with subtype B. Here, we describe the sequencing and construction of a new HIV-1 subtype C proviral clone (pZAC), replicating more than one order of magnitude better than the previous subtype C plasmids. We identify the env-region for being the determinant for the higher viral titers and the pZAC Env to be M-tropic. This higher replication capacity does not lead to a higher cytotoxicity compared to previously described subtype C viruses. In addition, the pZAC Vpu is also shown to be able to down-regulate CD4, but fails to fully counteract CD317.}, 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{KasangKalluvyaMajingeetal.2016, author = {Kasang, Christa and Kalluvya, Samuel and Majinge, Charles and Kongola, Gilbert and Mlewa, Mathias and Massawe, Irene and Kabyemera, Rogatus and Magambo, Kinanga and Ulmer, Albrecht and Klinker, Hartwig and Gschmack, Eva and Horn, Anne and Koutsilieri, Eleni and Preiser, Wolfgang and Hofmann, Daniela and Hain, Johannes and M{\"u}ller, Andreas and D{\"o}lken, Lars and Weissbrich, Benedikt and Rethwilm, Axel and Stich, August and Scheller, Carsten}, title = {Effects of Prednisolone on Disease Progression in Antiretroviral-Untreated HIV Infection: A 2-Year Randomized, Double-Blind Placebo-Controlled Clinical Trial}, series = {PLoS One}, volume = {11}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0146678}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146479}, pages = {e0146678}, year = {2016}, abstract = {Background HIV-disease progression correlates with immune activation. Here we investigated whether corticosteroid treatment can attenuate HIV disease progression in antiretroviral-untreated patients. Methods Double-blind, placebo-controlled randomized clinical trial including 326 HIV-patients in a resource-limited setting in Tanzania (clinicaltrials.gov NCT01299948). Inclusion criteria were a CD4 count above 300 cells/μl, the absence of AIDS-defining symptoms and an ART-na{\"i}ve therapy status. Study participants received 5 mg prednisolone per day or placebo for 2 years. Primary endpoint was time to progression to an AIDS-defining condition or to a CD4-count below 200 cells/μl. Results No significant change in progression towards the primary endpoint was observed in the intent-to-treat (ITT) analysis (19 cases with prednisolone versus 28 cases with placebo, p = 0.1407). In a per-protocol (PP)-analysis, 13 versus 24 study participants progressed to the primary study endpoint (p = 0.0741). Secondary endpoints: Prednisolone-treatment decreased immune activation (sCD14, suPAR, CD38/HLA-DR/CD8+) and increased CD4-counts (+77.42 ± 5.70 cells/μl compared to -37.42 ± 10.77 cells/μl under placebo, p < 0.0001). Treatment with prednisolone was associated with a 3.2-fold increase in HIV viral load (p < 0.0001). In a post-hoc analysis stratifying for sex, females treated with prednisolone progressed significantly slower to the primary study endpoint than females treated with placebo (ITT-analysis: 11 versus 21 cases, p = 0.0567; PP-analysis: 5 versus 18 cases, p = 0.0051): No changes in disease progression were observed in men. Conclusions This study could not detect any significant effects of prednisolone on disease progression in antiretroviral-untreated HIV infection within the intent-to-treat population. However, significant effects were observed on CD4 counts, immune activation and HIV viral load. This study contributes to a better understanding of the role of immune activation in the pathogenesis of HIV infection.}, 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{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{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{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} }