Krawczak, Michael

[["dc.bibliographiccitation.artnumber","e0224082"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","PLoS One"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Winkler, Michael"],["dc.contributor.author","Gärtner, Sabine"],["dc.contributor.author","Markus, Lara"],["dc.contributor.author","Hoffmann, Markus"],["dc.contributor.author","Nehlmeier, Inga"],["dc.contributor.author","Krawczak, Michael"],["dc.contributor.author","Sauermann, Ulrike"],["dc.contributor.author","Pöhlmann, Stefan"],["dc.date.accessioned","2019-11-05T08:51:28Z"],["dc.date.accessioned","2021-10-27T13:13:08Z"],["dc.date.available","2019-11-05T08:51:28Z"],["dc.date.available","2021-10-27T13:13:08Z"],["dc.date.issued","2019"],["dc.description.abstract","The experimental infection of rhesus macaques (rh) with simian immunodeficiency virus (SIV) is an important model for human immunodeficiency virus (HIV) infection of humans. The interferon-induced transmembrane protein 3 (IFITM3) inhibits HIV and SIV infection at the stage of host cell entry. However, it is still unclear to what extent the antiviral activity of IFITM3 observed in cell culture translates into inhibition of HIV/SIV spread in the infected host. We have shown previously that although rhIFITM3 inhibits SIV entry into cultured cells, polymorphisms in the rhIFITM3 gene are not strongly associated with viral load or disease progression in SIV infected macaques. Here, we examined whether rhIFITM3(2), which is closely related to rhIFITM3 at the sequence level, exerts antiviral activity and whether polymorphisms in the rhIFITM3(2) gene impact the course of SIV infection. We show that expression of rhIFITM3(2) is interferon-inducible and inhibits SIV entry into cells, although with reduced efficiency as compared to rhIFITM3. We further report the identification of 19 polymorphisms in the rhIFITM3(2) gene. However, analysis of a well characterized cohort of SIV infected macaques revealed that none of the polymorphisms had a significant impact upon the course of SIV infection. These results and our previous work suggest that polymorphisms in the rhIFITM3 and rhIFITM3(2) genes do not strongly modulate the course of SIV infection in macaques."],["dc.identifier.doi","10.1371/journal.pone.0224082"],["dc.identifier.pmid","31682595"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16596"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/91754"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.relation.eissn","1932-6203"],["dc.relation.issn","1932-6203"],["dc.relation.orgunit","Deutsches Primatenzentrum"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","599"],["dc.title","Role of rhesus macaque IFITM3(2) in simian immunodeficiency virus infection of macaques"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e25474"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","PLoS ONE"],["dc.bibliographiccitation.volume","6"],["dc.contributor.author","Siddiqui, Roman A."],["dc.contributor.author","Krawczak, Michael"],["dc.contributor.author","Platzer, Matthias"],["dc.contributor.author","Sauermann, Ulrike"],["dc.date.accessioned","2019-07-09T11:54:02Z"],["dc.date.available","2019-07-09T11:54:02Z"],["dc.date.issued","2011-10-13"],["dc.description.abstract","In HIV infection, TLR7-triggered IFN-a production exerts a direct antiviral effect through the inhibition of viral replication, but may also be involved in immune pathogenesis leading to AIDS. TLR7 could also be an important mediator of vaccine efficacy. In this study, we analyzed polymorphisms in the X-linked TLR7 gene in the rhesus macaque model of AIDS. Upon resequencing of the TLR7 gene in 36 rhesus macaques of Indian origin, 12 polymorphic sites were detected. Next, we identified three tightly linked single nucleotide polymorphisms (SNP) as being associated with survival time. Genotyping of 119 untreated, simian immunodeficiency virus (SIV)-infected male rhesus macaques, including an ‘MHC adjusted’ subset, revealed that the three TLR7 SNPs are also significantly associated with set-point viral load. Surprisingly, this effect was not observed in 72 immunized SIV-infected male monkeys. We hypothesize (i) that SNP c.13G.A in the leader peptide is causative for the observed genotype-phenotype association and that (ii) the underlying mechanism is related to RNA secondary structure formation. Therefore, we investigated a fourth SNP (c.-17C.T), located 17 bp upstream of the ATG translation initiation codon, that is also potentially capable of influencing RNA structure. In c.13A carriers, neither set-point viral load nor survival time were related to the c.-17C.T genotype. In c.13G carriers, by contrast, the c.-17C allele was significantly associated with prolonged survival. Again, no such association was detected among immunized SIV-infected macaques. Our results highlight the dual role of TLR7 in immunodeficiency virus infection and vaccination and imply that it may be important to control human AIDS vaccine trials, not only for MHC genotype, but also for TLR7 genotype."],["dc.format.extent","10"],["dc.identifier.doi","10.1371/journal.pone.0025474"],["dc.identifier.pmid","22022401"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8344"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60554"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 2.5"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.5"],["dc.title","Association of TLR7 Variants with AIDS-Like Disease and AIDS Vaccine Efficacy in Rhesus Macaques"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0172847"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","PLOS ONE"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Winkler, Michael"],["dc.contributor.author","Gärtner, Sabine"],["dc.contributor.author","Wrensch, Florian"],["dc.contributor.author","Krawczak, Michael"],["dc.contributor.author","Sauermann, Ulrike"],["dc.contributor.author","Pöhlmann, Stefan"],["dc.date.accessioned","2019-07-09T11:43:17Z"],["dc.date.available","2019-07-09T11:43:17Z"],["dc.date.issued","2017"],["dc.description.abstract","nterferon-induced transmembrane proteins (IFITMs) have been recognized as important antiviral effectors of the innate immune system, both in cell culture and in infected humans. In particular, polymorphisms of the human IFITM3 gene have been shown to affect disease severity and progression in influenza A virus (FLUAV) and human immunodeficiency virus (HIV) infection, respectively. Rhesus macaques (Macaca mulatta) are commonly used to model human infections and the experimental inoculation of these animals with simian immunodeficiency virus (SIV) is one of the best models for HIV/AIDS in humans. However, information on the role of IFITM3 in SIV infection of rhesus macaques is currently lacking. We show that rhesus macaque (rh) IFITM3 inhibits SIV and FLUAV entry in cell culture, although with moderately reduced efficiency as compared to its human counterpart. We further report the identification of 16 polymorphisms in the rhIFITM3 gene, three of which were exonic and synonymous while the remainder was located in non-coding regions. Employing previously characterized samples from two cohorts of SIV-infected rhesus macaques, we investigated the relationship between these rhIFITM3 polymorphisms and both AIDS-free survival time and virus load. In cohort 1, several intronic polymorphisms were significantly associated with virus load or survival. However, an association with both parameters was not observed and significance was lost in most cases when animals were stratified for the presence of MHC allele Mamu-A1 001. Moreover, no significant genotype-phenotype associations were detected in cohort 2. These results suggest that, although IFITM3 can inhibit SIV infection in cell culture, genetic variation in rhIFITM3 might have only a minor impact on the course of SIV infection in experimentally infected animals."],["dc.identifier.doi","10.1371/journal.pone.0172847"],["dc.identifier.pmid","28257482"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14379"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58850"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Rhesus macaque IFITM3 gene polymorphisms and SIV infection"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]