Ignacio G Bravo

IDIBELL Bellvitge Biomedical Research Institute, Barcino, Catalonia, Spain

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Publications (58)251.48 Total impact

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    ABSTRACT: In Catalonia, a screening protocol for cervical cancer including Human Papillomaviruses (HPVs) DNA testing using the Digene Hybrid Capture assay (HC2) was implemented in 2006. In order to monitor inter-laboratory reproducibility, a proficiency testing (PT) survey of the HPVs samples was launched in 2008. The aim of this study was to explore the repeatability of HC2 performance. Participant laboratories provided annually twenty samples, five randomly chosen samples from each of the following relative light units (RLU) intervals: <0.5; 0.5-0.99; 1-9.99; and ≥10. Kappa statistics was used to determine the agreement level between the original and the PT readings. The nature and origin of the discrepant results were calculated by bootstrapping. A total of 946 specimens were retested. Kappa values were 0.91 for positive/negative categorical classification and 0.79 for the four RLU intervals studied. Sample retesting yielded systematically lower RLU values than the original test (p<0.005), independently of the time elapsed between both determinations (median 53 days), possibly due to freeze-thaw cycles. The probability for a sample to show clinically discrepant results upon retesting was a function of the RLU value: samples with RLU in the 0.5-5 interval showed 10.80% probability to yield discrepant results (95% CI:7.86-14.33) compared to 0.85% probability for samples outside this interval (95% CI:0.17-1.69,). Globally, HC2 assay shows a high inter-laboratory concordance. We have identified differential confidence thresholds and suggested the guidelines for inter-laboratory PT in the future, as analytical quality assessment of the HPVs DNA detection remains a central component of the screening program for cervical cancer prevention.
    Journal of clinical microbiology 02/2014; · 4.16 Impact Factor
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    ABSTRACT: Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2 and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analysed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative Eptesicus isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E.serotinus and E.isabellinus) argues against strict host specificity. Finally, the description of a second non-coding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.
    Genome Biology and Evolution 01/2014; · 4.76 Impact Factor
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    ABSTRACT: Abstract BACKGROUND: Human papillomavirus (HPV) contribution in vulvar intraepithelial lesions (VIN) and invasive vulvar cancer (IVC) is not clearly established. This study provides novel data on HPV markers in a large series of VIN and IVC lesions. METHODS: Histologically confirmed VIN and IVC from 39 countries were assembled at the Catalan Institute of Oncology (ICO). HPV-DNA detection was done by polymerase chain reaction using SPF-10 broad-spectrum primers and genotyping by reverse hybridisation line probe assay (LiPA25) (version 1). IVC cases were tested for p16(INK4a) by immunohistochemistry (CINtec histology kit, ROCHE). An IVC was considered HPV driven if both HPV-DNA and p16(INK4a) overexpression were observed simultaneously. Data analyses included algorithms allocating multiple infections to calculate type-specific contribution and logistic regression models to estimate adjusted prevalence (AP) and its 95% confidence intervals (CI). RESULTS: Of 2296 cases, 587 were VIN and 1709 IVC. HPV-DNA was detected in 86.7% and 28.6% of the cases respectively. Amongst IVC cases, 25.1% were both HPV-DNA and p16(INK4a) positive. IVC cases were largely keratinising squamous cell carcinoma (KSCC) (N=1234). Overall prevalence of HPV related IVC cases was highest in younger women for any histological subtype. SCC with warty or basaloid features (SCC_WB) (N=326) were more likely to be HPV and p16(INK4a) positive (AP=69.5%, CI=63.6-74.8) versus KSCC (AP=11.5%, CI=9.7-13.5). HPV 16 was the commonest type (72.5%) followed by HPV 33 (6.5%) and HPV 18 (4.6%). Enrichment from VIN to IVC was significantly high for HPV 45 (8.5-fold). CONCLUSION: Combined data from HPV-DNA and p16(INK4a) testing are likely to represent a closer estimate of the real fraction of IVC induced by HPV. Our results indicate that HPV contribution in invasive vulvar cancer has probably been overestimated. HPV 16 remains the major player worldwide.
    European Journal of Cancer 11/2013; 49(16):3450-61. · 5.06 Impact Factor
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    ABSTRACT: Genital warts (GWs) and Laryngeal Papillomatosis (LP) are two usually-benign pathologies related with Human Papillomaviruses (HPVs) infection, mainly HPV6 and HPV11. The aim of this work was to describe the genetic diversity of HPV6 and HPV11 isolates found in GWs and LPs, and to analyze the differential involvement of viral variants in either lesion. Two hundred thirty-one (231) samples diagnosed as GWs (198) or LP (33) and caused by HPV6 or HPV11 monoinfections were analyzed. The phylogenetic relationships of the retrieved viral sequences (170) were explored. We have identified the long control region and the intergenic E2-L2 region as the two most variable regions in both HPV6 and HPV11 genomes. We have generated new HPV6 (166) or HPV11 (65) partial sequences from GWs and LPs lesions spanning both regions and studied them in the context of all available sequences of both types (final n=412). Our results show a significant (p <0.01) differential presence of HPV6 variants among both pathologies, with HPV6 B variants being preferentially found in GW vs. LP samples. No differential involvement of HPV11 variants is observed. Our findings suggest that different HPV6 variants may either show differential tropism or have different potential to induce lesions in different epithelia. This article is protected by copyright. All rights reserved.
    Clinical Microbiology and Infection 10/2013; · 4.58 Impact Factor
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    ABSTRACT: Low-risk human papillomaviruses (LR-HPVs) have been associated occasionally with clinically and pathologically unusual anogenital malignancies. The relation between clinicopathologic features and any pathogenetic role of LR-HPV remains unclear. From a global study of 13,328 anogenital carcinomas, we identified 57 cases in which whole-tissue polymerase chain reaction using SPF10-LiPA25 showed single LR-HPV infection. In 43/46 (93.5%) available carcinomas, multiple polymerase chain reaction assays confirmed single detection of HPV6, 11, 42, 44, or 70 DNA. In 75% (n=32) of these, LR-HPV DNA was confirmed in tumor cells by laser capture microdissection. In 2 cases, including 1 adenocarcinoma, viral DNA was only found outside the tumor. All anogenital tumors with confirmed HPV6/11 showed a distinctive range of papillary, warty or warty-basaloid, squamous, or transitional histology with patchy or negative p16 expression. HPV6-associated cervical tumors occurred at a low median age. HPV42/70 was associated with typical squamous cell carcinoma showing diffuse p16 staining like high-risk HPV-related malignancies. HPV44 was found in malignant cells in 1 case. Viral taxonomy and theoretical analysis show that HPV6/11 belong to a different genus from HPV42/70 with E6/E7 gene products that would not bind pRb or p53, whereas HPV42/70 could bind pRb. Our data support the causal involvement of LR-HPVs in the carcinogenesis of <2% of anogenital malignancies of 2 distinct clinicopathologic patterns related to the genetic structure of the HPV types 6/11 and 70/42. HPV42/70 was associated with typical squamous carcinomas. Importantly all carcinomas associated with HPV6/11 globally showed verruco-papillary, well-differentiated, squamous, or transitional histology without p16 expression.
    The American journal of surgical pathology 09/2013; 37(9):1299-310. · 4.06 Impact Factor
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    ABSTRACT: High-risk (HR) HPV-associated carcinogenesis is mainly driven by the overexpression of E7 and E6 oncoproteins following the viral DNA integration and the concomitant loss of the E2 ORF However, integration of HR-HPV DNA is not systematically observed in cervical cancers. The E2 protein acts a transcription factor that governs viral oncogenes expression. Methylation of CpGs in the E2-binding sites (E2BS) in the viral long control region abrogates E2 binding, thus impairing the E2-mediated regulation of E7/E6 transcription. Here, a High Resolution Melting (HRM) PCR was developed to quantitatively analyze the methylation status of E2BS#1, E2BS#2 and Sp1-binding site in 119 HPV16-positive cervical smears. This is a rapid assay, suitable for the analysis of cervical samples. The proportion of cancer samples with methylated E2BS#1, E2BS#2 and Sp1 binding site CpGs was 47% whereas the vast majority of samples diagnosed as normal, LSIL or HSIL harbored unmethylated CpGs. Methylation levels varied widely since some cancer samples harbored up to 60% of methylated HPV16 genomes. A pyrosequencing approach was used as a confirmation test and highlighted that quantitative measurement of methylation can be achieved by HRM PCR. Its prognostic value deserves to be investigated alone or in association with other biomarkers. The reliability of this single-tube assay offers great opportunities for the investigation of HPV16 methylation in other HPV-related cancer such as head and neck cancers, a major public health burden.
    Journal of clinical microbiology 07/2013; · 4.16 Impact Factor
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    ABSTRACT: Infection by papillomaviruses (PVs) has been linked to different types of neoplasias, in both human and non-human hosts. Knowledge about PV diversity is essential to reliably infer the evolutionary history of these pathogens and to elucidate the link between infection and disease. We cloned and sequenced the complete genome of a novel PV, EhelPV1, isolated from hair bulbs from a captive straw-colored fruit bat Eidolon helvum (Pteropodidae, Chiroptera). We also retrieved partial sequences of the E1 and L1 genes from hair bulbs from a captive Indian flying fox Pteropus giganteus (Pteropodidae, Chiroptera). The detected virus (PgigPV1) presumably corresponded to a novel type as well. Maximum likelihood phylogenetic analyses were conducted using a representative collection of 132 PVs. EhelPV1 belonged to the Lambda+Mu-PV crown group and was most closely related to another bat PV, MschPV2. Both fragments of PgigPV1 were placed alongside with EhelPV1. The novel PVs were phylogenetically distant from other previously described bat PVs, namely MrPV1, MschPV1 and RaPV1. We have further characterized the sequence patterns of the E2-binding sites occurring in the upstream regulatory region of Lambda+Mu-PVs. Common fingerprints within this region are shared by certain PVs. However, there is not a sharp correspondence between the repertoire of transcription factor binding sites in the viral regulatory region and host range, tissue tropism or viral life style. Our results reinforce the hypothesis that PVs have undergone an initial radiation prior to the divergence of the mammalian hosts, giving rise to the present-day PV crown groups.
    Veterinary Microbiology 02/2013; · 3.13 Impact Factor
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    ABSTRACT: Human papillomaviruses (HPVs) comprise a diverse group, and have different epithelial tropisms and life-cycle strategies. Many HPVs are classified as low-risk, as they are only very rarely associated with neoplasia or cancer in the general population. These HPVs typically cause inapparent/inconspicuous infections, or benign papillomas, which can persist for months or years, but which are eventually resolved by the host's immune system. Low-risk HPVs are difficult to manage in immunosuppressed people and in individuals with genetic predispositions, and can give rise to papillomatosis, and in rare instances, to cancer. The high-risk HPV types are, by contrast, a cause of several important human cancers, including almost all cases of cervical cancer, a large proportion of other anogenital cancers and a growing number of head and neck tumours. The high-risk HPV types constitute a subset of the genus Alphapapillomavirus that are prevalent in the general population, and in most individuals cause only inconspicuous oral and genital lesions. Cancer progression is associated with persistent high-risk HPV infection and with deregulated viral gene expression, which leads to excessive cell proliferation, deficient DNA repair, and the accumulation of genetic damage in the infected cell. Although their life-cycle organisation is broadly similar to that of the low-risk HPV types, the two groups differ significantly in their capacity to drive cell cycle entry and cell proliferation in the basal/parabasal cell layers. This is thought to be linked, at least in part, to different abilities of the high- and low-risk E6 proteins to modulate the activity of p53 and PDZ-domain proteins, and the differential ability of the E7 proteins to target the several different members of the retinoblastoma protein family. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.
    Vaccine 11/2012; 30 Suppl 5:F55-70. · 3.77 Impact Factor
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    ABSTRACT: BACKGROUND: Certain human papillomaviruses (HPVs) are the causative agents of cervical carcinomas in humans. The identification of the link between infection and cancer has resulted in the successful establishment of clinical strategies such as screening or vaccination programs, aiming to prevent this pathology. More than 150 different HPVs have been described and classified and the large majority of them are not related to cancer. The genus Alphapapillomavirus encompasses many PVs, some of which are identified in humans as oncogenic, according to the epidemiological connection between infection and cervical cancer. Variants of some of these "high-risk" HPVs may have an increased involvement in cervical cancer, although definitive data are still wanting. The aim of the present work was to analyze the presence of HPV33, HPV45 and HPV58 variants in cases of cervical cancer. METHODS: Samples from cervical lesions in the context of different cervical cancer surveys were analyzed for presence of HPV DNA. Samples positive for HPV33, HPV45 or HPV58 DNA were selected and the E6/E7 genes were amplified and sequenced. The phylogenetic relationships of these sequences were inferred using an evolutionary placement algorithm and accordingly classified at the variant level. RESULTS: All viral E6/E7 sequences were successfully placed in the classification schemes of the corresponding viruses. For HPV33 (n=23), 45 (n=61) or 58 (n=29), the distribution of variants found in cases of cervical cancer is not a random sample of the corresponding diversity. In all three HPVs, the respective A variants were more prevalent in the viral DNA-positive cases of cervical cancer analyzed. This is the first study trying to discern the phylogenetic connection between variants of the oncogenic HPV33, 45 and 58, and squamous cell carcinoma of the cervix.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 09/2012; · 3.22 Impact Factor
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    ABSTRACT: All amniotes are probably infected by specific papillomaviruses (PVs), but knowledge about PV diversity remains sparse. An insufficient taxon sampling, and a focus on humans as hosts, may perturb phylogenetic analyses leading to wrong conclusions about PV evolution. We performed a systematic approach to explore the diversity of PVs combining rolling circle amplification with the use of "universal" primers to search for the presence of novel PV sequences in animal samples. We communicate 12 sequences putatively corresponding to novel PVs gained from 10 host species in eight mammal families: Bovidae, Canidae, Cervidae, Equidae, Hominidae, Phocoenidae, Procyonidae and Pteropodidae. The phylogenetic position of the new sequences was inferred with an evolutionary placement algorithm under a Maximum Likelihood framework using a pre-computed, well-resolved tree constructed with the E1-E2-L1 gene sequences as a backbone. The new sequences were phylogenetically diverse and could be respectively placed with confidence within all four PV crown groups. The prevailing presence of sequences from the crown groups Alpha+Omikron-PVs and Beta+Xi-PVs may correspond to an increased viral diversity in these taxa, or rather reflect a combination of anthropocentric bias and preferential amplification from commonly used "universal" primers. Our results combined with literature data support the view that the number and diversity of animal PVs is overwhelmingly large.
    Molecular Phylogenetics and Evolution 08/2012; 65(3):883-91. · 4.07 Impact Factor
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    Carsten Münk, Anouk Willemsen, Ignacio G Bravo
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    ABSTRACT: BACKGROUND: The APOBEC3 (A3) genes play a key role in innate antiviral defense in mammals by introducing directed mutations in the DNA. The human genome encodes for seven A3 genes, with multiple splice alternatives. Different A3 proteins display different substrate specificity, but the very basic question on how discerning self from non-self still remains unresolved. Further, the expression of A3 activity/ies shapes the way both viral and host genomes evolve. RESULTS: We present here a detailed temporal analysis of the origin and expansion of the A3 repertoire in mammals. Our data support an evolutionary scenario where the genome of the mammalian ancestor encoded for at least one ancestral A3 gene, and where the genome of the ancestor of placental mammals (and possibly of the ancestor of all mammals) already encoded for an A3Z1-A3Z2-A3Z3 arrangement. Duplication events of the A3 genes have occurred independently in different lineages: humans, cats and horses. In all of them, gene duplication has resulted in changes in enzyme activity and/or substrate specificity, in a paradigmatic example of convergent adaptive evolution at the genomic level. Finally, our results show that evolutionary rates for the three A3Z1, A3Z2 and A3Z3 motifs have significantly decreased in the last 100 Mya. The analysis constitutes a textbook example of the evolution of a gene locus by duplication and sub/neofunctionalization in the context of virus-host arms race. CONCLUSIONS: Our results provide a time framework for identifying ancestral and derived genomic arrangements in the APOBEC loci, and to date the expansion of this gene family for different lineages through time, as a response to changes in viral/retroviral/retrotransposon pressure.
    BMC Evolutionary Biology 05/2012; 12(1):71. · 3.29 Impact Factor
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    ABSTRACT: One way of creating phenotypic diversity is through alternative splicing of precursor mRNAs. A gene that has evolved a hypervariable form is Down syndrome cell adhesion molecule (Dscam-hv), which in Drosophila melanogaster can produce thousands of isoforms via mutually exclusive alternative splicing. The extracellular region of this protein is encoded by three variable exon clusters, each containing multiple exon variants. The protein is vital for neuronal wiring where the extreme variability at the somatic level is required for axonal guidance, and it plays a role in immunity where the variability has been hypothesised to relate to recognition of different antigens. Dscam-hv has been found across the Pancrustacea. Additionally, three paralogous non-hypervariable Dscam-like genes have also been described for D. melanogaster. Here we took a bioinformatics approach, building profile Hidden Markov Models to search across species for putative orthologs to the Dscam genes and for hypervariable alternatively spliced exons, and inferring the phylogenetic relationships among them. Our aims were to examine whether Dscam orthologs exist outside the Bilateria, whether the origin of Dscam-hv could lie outside the Pancrustacea, when the Dscam-like orthologs arose, how many alternatively spliced exons of each exon cluster were present in the most common recent ancestor, and how these clusters evolved. Our results suggest that the origin of Dscam genes may lie after the split between the Cnidaria and the Bilateria and supports the hypothesis that Dscam-hv originated in the common ancestor of the Pancrustacea. Our phylogeny of Dscam gene family members shows six well-supported clades: five containing Dscam-like genes and one containing all the Dscam-hv genes, a seventh clade contains arachnid putative Dscam genes. Furthermore, the exon clusters appear to have experienced different evolutionary histories. Dscam genes have undergone independent duplication events in the insects and in an arachnid genome, which adds to the more well-known tandem duplications that have taken place within Dscam-hv genes. Therefore, two forms of gene expansion seem to be active within this gene family. The evolutionary history of this dynamic gene family will be further unfolded as genomes of species from more disparate groups become available.
    BMC Evolutionary Biology 04/2012; 12:53. · 3.29 Impact Factor
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    ABSTRACT: Squamous cell carcinoma (SCC) represents the most common genital malignant tumor in horses. Similar to humans, papillomaviruses (PVs) have been proposed as etiological agents and recently Equine papillomavirus type 2 (EcPV2) has been identified in a subset of genital SCCs. The goals of this study were (1) to determine the prevalence of EcPV2 DNA in tissue samples from equine genital SCCs, penile intraepithelial neoplasia (PIN) and penile papillomas, using EcPV2-specific PCR, (2) to examine the prevalence of latent EcPV2 infection in healthy genital mucosa and (3) to determine genetic variability within EcPV2 and to disentangle phylogenetic relationships of EcPV2 among PVs. EcPV2 DNA was detected in all but one penile SCC (15/16), in all PIN lesions (8/8) and penile papillomas (4/4). Additionally, EcPV2 DNA was demonstrated in one of two metastasized lymph nodes, one contact metastasis in the mouth, two vaginal and one anal lesion. In healthy horses, EcPV2 DNA was detected in 10% (4/39) of penile swabs but in none of vulvovaginal swabs (0/20). This study confirms the presence of EcPV2 DNA in equine genital SCCs and shows its involvement in anal lesions, a lymph node and contact metastases. Latent EcPV2 presence was also shown in normal male genital mucosa. We found that different EcPV2 variants cocirculate among horses and that EcPV2 is related to the Delta+Zeta PVs and is only a very distant relative of high-risk human PVs causing genital cancer. Thus, similar viral tropism and similar malignant outcome of the infection do not imply close evolutionary relationship.
    Veterinary Microbiology 02/2012; 158(1-2):33-41. · 3.13 Impact Factor
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    ABSTRACT: Certain Human Papillomaviruses (HPVs) are the infectious agents involved in cervical cancer development. Detection of HPVs DNA is part of the cervical cancer screening protocols and HPVs genotyping has been proposed for its inclusion in these preventive programs. The aim of this study was to evaluate three novel genotyping tests, namely Qiagen LQ, RH and PS, in clinical samples with and without abnormalities. For this, 305 cervical samples were processed and the results of the evaluated techniques were compared with those obtained in the HPVs diagnostic process in our lab, by using HC2 and Linear Array (LA) technologies. The concordances and kappa statistics (k) for each technique compared with HC2 were 98.69% (k = 0.94) for LQ, 98.03% (k = 0.91) for RH and 91.80% (k = 0.82) for PS. There was a very good agreement in HPVs type-specific concordance for the most prevalent types HPV16 (kappa range = 0.83-0.90), HPV18 (k.r.= 0.74-0.80) and HPV45 (k.r.= 0.82-0.90). The three tests showed an overall good concordance for HPVs detection when compared with HR-HC2 system. LQ and RH rendered lower detection rate for multiple infections than LA genotyping. However, our understanding of the clinical significance of multiple HPVs infections is still incomplete and therefore the relevance of the lower ability to detect multiple infections needs to be evaluated.
    Infectious Agents and Cancer 11/2011; 6:23.
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    ABSTRACT: Cutaneous human papillomaviruses (HPVs) are a heterogeneous, nonmonophyletic assembly, comprising about 50 characterized types and at least 133 isolates putatively representing new types. Their natural history of infection and potential association with nonmelanoma skin cancer are not well understood. Several PCR systems have been developed that amplify a broad spectrum of cutaneous HPVs. However, amplicon genotyping by sequencing or reverse line blot assays are complex and not well suited for high-throughput analyses. We developed a novel multiplex cutaneous papillomavirus genotyping (McPG) assay for 38 defined and 20 putative cutaneous HPVs of the beta, gamma, mu, and nu genera. Viral DNA was amplified by the use of a modified single-tube nested "hanging-droplet" FAP PCR. The amplifiable papillomavirus (PV) spectrum was enlarged by the use of 9 outer and 13 inner primers. Biotinylated PCR products were hybridized to type-specific oligonucleotide probes coupled to fluorescence-labeled polystyrene beads and analyzed using Luminex technology. Analytical sensitivity was analyzed for 38 defined HPVs and was ≤100 genome copies for all types. Integrated β-globin primers allow for simultaneous DNA quality control. McPG is characterized by high reproducibility (κ= 0.84, 95% confidence interval = 0.79 to 0.88), good concordance with the original nested FAP PCR, followed by sequencing (70.2% complete or partial agreement) when 322 skin biopsy DNA samples were analyzed, and improved ability to detect multiple infections (on average 2.5 HPV types per HPV-positive sample compared to 1.7 HPV types with nested FAP-PCR). In conclusion, McPG is a powerful tool for genotyping multiple cutaneous HPVs in a high-throughput format and is thus suitable for large-scale epidemiological studies.
    Journal of clinical microbiology 08/2011; 49(10):3560-7. · 4.16 Impact Factor
  • Radiotherapy and Oncology 02/2011; 98:S25. · 4.52 Impact Factor
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    ABSTRACT: 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 analyzed human and porcine APOBEC3 (A3) proteins. This multigene family of cytidine deaminases contributes to the cellular intrinsic immunity and act as potent inhibitors of retroviruses and retrotransposons. Our data show that the porcine A3 gene locus on chromosome 5 consists of the two single-domain genes A3Z2 and A3Z3. The evolutionary relationships of the A3Z3 genes reflect the evolutionary history of mammals. The two A3 genes encode at least four different mRNAs: A3Z2, A3Z3, A3Z2-Z3, and A3Z2-Z3 splice variant A (SVA). Porcine and human A3s have been tested toward their antiretroviral activity against PERV and murine leukemia virus (MuLV) using novel single-round reporter viruses. The porcine A3Z2, A3Z3 and A3Z2-Z3 were packaged into PERV particles and inhibited PERV replication in a dose-dependent manner. The antiretroviral effect correlated with editing by the porcine A3s with a trinucleotide preference for 5' TGC for A3Z2 and A3Z2-Z3 and 5' CAC for A3Z3. These results strongly imply that human and porcine A3s could inhibit PERV replication in vivo, thereby reducing the risk of infection of human cells by PERV in the context of pig-to-human xenotransplantation.
    Journal of Virology 02/2011; 85(8):3842-57. · 5.08 Impact Factor
  • Trends in Microbiology 02/2011; 19(2):50-1. · 8.43 Impact Factor
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    ABSTRACT: Squamous cell carcinoma (SCC) represents the most common malignant tumour of the eye and external genitals in horses. Comparable to humans, papillomaviruses (PV) have been proposed as etiological agents of cancer in horses and recently, Equine papillomavirus type 2 (EcPV2) has been identified in genital SCCs. Hitherto it had never been demonstrated in ocular SCCs. The first goal of this study was to determine the prevalence of EcPV2 DNA in tissue samples from equine genital and ocular SCCs, genital papillomas and penile intraepithelial neoplasia (PIN) lesions, using EcPV2-specific PCR. The second goal was to investigate the possibility of latent EcPV2 infection in the genital and ocular mucosa of healthy horses on swabs obtained from the eye, penis, vulvovaginal region and cervix. EcPV2 DNA was detected in all genital SCCs (17/17), genital papillomas (8/8), PIN lesions (11/11) and ocular SCCs (9/9). In healthy horses, EcPV2 DNA was detected in 43% (17/40) of penile swabs, 53% (9/17) of vulvovaginal swabs, 47% (8/17) of cervical swabs and 57% (32/56) of ocular swabs. This study confirms the presence of EcPV2 DNA in equine genital SCCs. Moreover, we demonstrate for the first time its involvement in other genital lesions and in ocular SCCs and latent EcPV2 infections in normal genital (including cervical) and ocular equine mucosa. The close relatives of EcPV2 are associated to cutaneous lesions, and this virus is not related to high-risk human papillomaviruses causing cervical cancer. Thus, similar viral tropism does not imply close evolutionary relationship.
    Veterinary Microbiology 01/2011; 147(3-4):292-9. · 3.13 Impact Factor
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    ABSTRACT: The associations between pathogens and their hosts are complex and can result from a variety of evolutionary processes including codivergence, lateral transfer, or duplication. Papillomaviruses (PVs) are double-stranded DNA viruses ubiquitously present in mammals and are a suitable target for rigorous statistical tests of potential virus-host codivergence. We analyze the evolutionary dynamics of PV diversification by comparing robust phylogenies of PVs and their respective hosts using different statistical approaches to assess topological and branch-length congruence. Mammalian PVs segregated into four diverse major clades that overlapped to varying degrees in terms of their mammalian host lineages. The hypothesis that PVs and hosts evolved independently was globally rejected (P = 0.0001), although only 90 of 207 virus-host associations (43%) were significant in individual tests. Virus-host codivergence accounted roughly for one-third of the evolutionary events required to reconcile PV-host evolutionary histories. When virus-host associations were analyzed locally within each of the four viral clades, numerous independent topological congruencies were identified that were incompatible with respect to the global trees. These results support an evolutionary scenario in which early PV radiation was followed by independent codivergence between viruses within each of the major clades and their hosts. Moreover, heterogeneous groups of closely related PVs infecting non-related hosts suggest several interspecies transmission events. Our results argue thus for the importance of alternative events in PV evolution, in contrast to the prevailing opinion that these viruses show a high degree of host specificity and codivergence.
    Molecular Biology and Evolution 01/2011; 28(7):2101-13. · 10.35 Impact Factor

Publication Stats

807 Citations
251.48 Total Impact Points

Institutions

  • 2012–2013
    • IDIBELL Bellvitge Biomedical Research Institute
      Barcino, Catalonia, Spain
    • Catalan Institute of Oncology
      • Infections and Cancer Unit
      Badalona, Catalonia, Spain
  • 2008–2012
    • University of Münster
      • Institute for Evolution and Biodiversity
      Münster, North Rhine-Westphalia, Germany
    • Cancer Research UK
      Londinium, England, United Kingdom
  • 2011
    • Ludwig-Maximilian-University of Munich
      • Department of Biology II
      München, Bavaria, Germany
    • University of Veterinary Medicine Hannover
      Hanover, Lower Saxony, Germany
  • 2010
    • Centro Superior de Investigación en Salud Pública (CSISP)
      Valenza, Valencia, Spain
    • Hospital la Magdalena
      Castellón, Valencia, Spain
  • 2004–2010
    • German Cancer Research Center
      Heidelburg, Baden-Württemberg, Germany
  • 2009
    • Heinrich-Heine-Universität Düsseldorf
      • Klinik für Gastroenterologie, Hepatologie und Infektiologie
      Düsseldorf, North Rhine-Westphalia, Germany
  • 2007
    • Charité Universitätsmedizin Berlin
      • Department of Dermatology, Venerology and Allergology
      Berlin, Land Berlin, Germany
  • 2005–2006
    • Universitat Rovira i Virgili
      • Department of Biochemistry and Biotechnology
      Tarragona, Catalonia, Spain
  • 2002
    • Universidad de León
      • Departamento de Biología Molecular
      León, Castile and Leon, Spain