Lutz Gissmann

German Cancer Research Center, Heidelburg, Baden-Württemberg, Germany

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Publications (290)1185.92 Total impact

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    ABSTRACT: Cervical cancer is one of the most common gynecological cancers in the world but in India, it is the top most cancer among women. Persistent infection with high-risk human papillomaviruses (HR-HPVs) is the most important risk factor. The sequence variation(s) in the most common HRHPV i.e. HPV type 16 leads to altered biological functions with possible clinical significance in the different geographical locations. Sixteen major variants (V1-V16) in full length L1 gene of HPV-16 were identified following analysis of 250 prospectively collected cervical cancer tissue biopsies and their effect on immunogenicity was studied. The effect of these major variations on the epitopes were predicted by in silico methods and the immunogenicity of variants and respective reference DNA vaccine constructs were evaluated by administration of prepared DNA vaccine constructs in female BALB/c mice to evaluate antibody titer. In the present study, L500F (V16) variation showed a significant ~2.7 fold (p<0.002) increase in antibody titer, whereas T379P (V8) showed ~0.4 fold (p<0.328) decrease after final injection. These results showed a promising roadmap for the development of DNA based vaccine and for the generation of effective response, though there is a need to study more prevalent variants of HPV in the Indian population.
    Full-text · Article · Oct 2015 · Scientific Reports
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    ABSTRACT: The use of whole viruses as antigen scaffolds is a recent development in vaccination that improves immunogenicity without the need for additional adjuvants. Previous studies highlighted the potential of foamy viruses (FVs) in prophylactic vaccination and gene therapy. Replication-competent FVs can trigger immune signaling and integrate into the host genome, resulting in persistent antigen expression and a robust immune response. Here, we explored feline foamy virus (FFV) proteins as scaffolds for therapeutic B and T cell epitope delivery in vitro. Infection- and cancer-related B and T cell epitopes were grafted into FFV Gag, Env, or Bet by residue replacement, either at sites of high local sequence homology between the epitope and the host protein or in regions known to tolerate sequence alterations. Modified proviruses were evaluated in vitro for protein steady state levels, particle release, and virus titer in permissive cells. Modification of Gag and Env was mostly detrimental to their function. As anticipated, modification of Bet had no impact on virion release and affected virus titers of only some recombinants. Further evaluation of Bet as an epitope carrier was performed using T cell epitopes from the model antigen chicken ovalbumin (OVA), human tyrosinase-related protein 2 (TRP-2), and oncoprotein E7 of human papillomavirus type 16 (HPV16E7). Transfection of murine cells with constructs encoding Bet-epitope chimeric proteins led to efficient MHC-I-restricted epitope presentation as confirmed by interferon-gamma enzyme-linked immunospot assays using epitope-specific cytotoxic T lymphocyte (CTL) lines. FFV infection-mediated transduction of cells with epitope-carrying Bet also induced T-cell responses, albeit with reduced efficacy, in a process independent from the presence of free peptides. We show that primate FV Bet is also a promising T cell epitope carrier for clinical translation. The data demonstrate the utility of replication-competent and -attenuated FVs as antigen carriers in immunotherapy.
    Preview · Article · Sep 2015 · PLoS ONE
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    ABSTRACT: Cervical cancer precursor screening by HPV testing has a low positive predictive value for advanced lesion. HPV16 RNA patterns characteristic for HPV16-transformed cells but based on laborious, cost-intensive singleplex NASBA reactions promised high value in triaging HPV16 DNA-positive women. We developed two high-throughput reverse transcriptase quantitative (RT-q) PCR assays for the HPV16 transcripts E6*I, E1^E4 and E1C and the cellular transcript ubiquitin C and analysed RNA of 158 singly HPV16 DNA-positive cervical cell samples archived in PreservCyt buffer for presence of transformation-associated HPV16 RNA patterns, i.e. upregulation of E6*I relative to E1^E4 and/or presence of E1C. HPV16 RNA patterns analyses classified 85% of 58 samples diagnosed≤CIN1 (no cytologically and histologically detectable cervical lesion or CIN grade 1) as negative and 90% of 59 samples diagnosed as≥CIN3 (CIN grade 3 or invasive cancer) as positive. Among 41 CIN grade 2 samples representing an intermediate lesion group, 49% were HPV16 RNA patterns-positive. Interestingly, 3 of 4 HPV16 RNA patterns-positive lesions initially diagnosed as≤CIN1 at follow-up 5-24 months later had progressed to≥CIN2. We successfully developed and validated a second generation of HPV16 RNA patterns assay by rapid RT-qPCR as triage marker for HPV16 DNA-positive women offering clinical utility to distinguish between need for immediate colposcopy and continuing observation. Limited follow-up data suggests that HPV16 RNA patterns-positivity in≤CIN1 lesions can predict disease progression. Copyright © 2015. Published by Elsevier Inc.
    No preview · Article · Jul 2015 · Gynecologic Oncology
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    ABSTRACT: The infection with high-risk human papillomavirus (HR-HPV) is the most important risk factor for development of cervical cancer. The intra-type variations of HPV have different biological and pathological consequences with respect to disease progression. In the present study, six major Indian variants were experimentally identified in E6 gene of HPV-16 and showed their impact on immunogenicity by in silico methods. Four different phylogenetic lineages were observed in sequences including European (E) prototype, European variant, Asian and American Asian variant classes and complete absence of African phylogenetic lineages. On the prediction of B- and T- cell epitopes, 18 & 23 potent epitopes for MHC-II alleles, 10 potent MHC-I and 15 B-cell epitopes in each reference and variant sequence were identified. Interestingly, the presence of variation H78Y and L83V result in creation of four new epitope for the HLA-DQA1*0101/DQB1*0501. Out of 15 B-cell predicted epitopes, three most potent epitopes were identified in both reference and variant sequence. Notably the amino acid stretch from amino acid 16 to 60 and 76 to 94 are very important for the immunological properties of E6 protein because these regions contain majority of the predicted epitopes. In future, this could control the cervical cancer by targeting these amino acid stretches for the development of HPV-16 vaccine. Copyright © 2015. Published by Elsevier B.V.
    Full-text · Article · Mar 2015 · Journal of virological methods
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    ABSTRACT: Eight HPV types (HPV26, 53, 66, 67, 68, 70, 73 and 82) that are phylogenetically closely related to 12 WHO-defined high-risk (HR-)HPV have been rarely but consistently identified as single HPV infections in about 3% of cervical cancer (CxCa) tissues. Due to lack of biological data, these types are referred to as probable/possible (p)HR-HPV. To analyze their biological activity in direct comparison to HR-HPV types, we selected 55 formalin-fixed paraffin-embedded (FFPE) CxCa tissues harboring single pHR-HPV infections (2-13 cases per type) and 266 tissues harboring single HR-HPV (7-40 cases per type) from a worldwide, retrospective, cross-sectional study. Single HPV infection was verified by two genotyping methods. Presence of type-specific spliced E6*I mRNA transcripts and expression of cellular proteins indicative of HPV transformation were assessed in all cases. In 55 CxCa tissues with pHR-HPV, E6*I mRNA expression was 100%, high p16INK4a, 98%; low pRb, 96%; low CyD1, 93% and low p53, 84%. Compared to HPV16 tissues as a reference, individual frequencies of these five markers did not differ significantly, either for any of the eight pHR-HPV and the 11 other HR-types individually, or for the groups of pHR- and HR-types without HPV16. We conclude that the eight pHR-HPV types, when present as a single infection in CxCa, are biologically active and affect the same cellular pathways as any of the fully-recognized carcinogenic HR-HPV types. Therefore we have provided molecular evidence of carcinogenicity for types currently classified as probably/possibly carcinogenic. Although this evidence is crucial for HPV type carcinogenicity classification, per se it is not sufficient for inclusion of these HPV types into population-wide primary and secondary prevention programs. Such decisions have to include careful estimation of effectiveness and cost-benefit analyses.
    Full-text · Article · Dec 2014 · The Journal of Pathology
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    Full-text · Article · Dec 2014 · Laryngo-Rhino-Otologie
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    ABSTRACT: Persistent infection with the high-risk Human Papillomavirus type 16 (HPV 16) is the causative event for the development of cervical cancer and other malignant tumors of the anogenital tract and of the head and neck. Despite many attempts to develop therapeutic vaccines no candidate has entered late clinical trials. An interesting approach is a DNA based vaccine encompassing the nucleotide sequence of the E6 and E7 viral oncoproteins. Because both proteins are consistently expressed in HPV infected cells they represent excellent targets for immune therapy. Here we report the development of 8 DNA vaccine candidates consisting of differently rearranged HPV-16 E6 and E7 sequences within one molecule providing all naturally occurring epitopes but supposedly lacking transforming activity. The HPV sequences were fused to the J-domain and the SV40 enhancer in order to increase immune responses. We demonstrate that one out of the 8 vaccine candidates induces very strong cellular E6- and E7- specific cellular immune responses in mice and, as shown in regression experiments, efficiently controls growth of HPV 16 positive syngeneic tumors. This data demonstrates the potential of this vaccine candidate to control persistent HPV 16 infection that may lead to malignant disease. It also suggests that different sequence rearrangements influence the immunogenecity by an as yet unknown mechanism.
    Full-text · Article · Nov 2014 · PLoS ONE
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    ABSTRACT: Infection with different species of cutaneous human papillomaviruses (cHPV) of genus alpha (cαHPVs) and associated skin disease are highly prevalent in solid organ transplant recipients (OTR), documenting the importance of the immunological control of HPV infection.Objectives To investigate the natural course of cαHPV-specific cellular and humoral immune responses during systemic long-term immunosuppression.Methods Integrating bead-based multiplex serology and flow cytometry we analyzed natural cαHPV-specific antibodies and TH cell responses against the major capsid protein L1 of HPV types 2, 27, 57 (species 4) and 3, 10 and 77 (species 2) in sera and blood of OTR before and after initiation of iatrogenic immunosuppression and in comparison to immunocompetent individuals (IC).ResultsAmong OTR we observed an overall 42% decrease in humoral L1-specific immune responses during the course of iatrogenic immunosuppression, comparing median values 30d before and 30d after initiation of immunosuppressive therapy (p < 0.05). This difference disappeared after long-term (>1 year) immunosuppression. The predominant cellular L1-specific immune response was of type TH1 (CD4+CD40L+IL-2+IFN-γ+). Consistent with the detected L1-specific antibody titres, L1-specific TH1 responses were unchanged in long-term immunosuppressed OTR compared to IC. Notably, cαHPV-L1-specific IL-2+/CD40L+CD4+ or IFN-γ+/CD40L+ CD4+ TH cell responses against any of the cαHPV-L1 types were significantly higher in OTR with clinically apparent common warts.Conclusion The systemic humoral immune response against cαHPV may reflect the individual degree of iatrogenic immunosuppression indicating a higher susceptibility for cαHPV infection among OTR during the early phase after organ transplantation. Humoral cαHPV-specific immune responses may show a reconstitution to pre-transplantation levels despite continuous potent immunosuppression.
    Full-text · Article · Nov 2014 · Journal of Dermatological Science
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    ABSTRACT: Helicobacter pylori infection that is usually acquired in childhood and lasts for lifetime is mostly asymptomatic but associated with severe gastrointestinal disease including cancer. During chronic infection, the gastric mucosa is histologically changing. This forces H. pylori to permanent adaptation in its gastric habitat by expression of different proteins which might be reflected in distinctive antibody patterns. To characterize dynamics of the immune response to H. pylori we analysed 1797 sera of a cross-sectional study representative for the German population (age range 1-82 years) with multiplex serology, a fluorescent bead-based antibody binding assay that allows simultaneous and quantitative detection of antibodies. Fifteen recombinant, affinity-purified H. pylori proteins (UreA, GroEL, Catalase, NapA, CagA, CagM, Cagδ, HP0231, VacA, HpaA, Cad, HyuA, Omp, HcpC and HP0305) were used as antigens. H. pylori seroprevalence (positivity for at least three antigens) was 48% and increased with age from 12% in children <15 years to 69% in females and 90% in males >65 years. Prevalences were highest (>83%) for Omp, VacA and GroEL. For 11 proteins, seroprevalence was higher in males than females (P < 0.05) from age 55 onwards. For all antigens, the median prevalence increase per age decade was stronger in males (8.4%, range 3.8-12.9%) than females (6.1%, range 3.4-10.8%). However, among seropositives the median number of antigens recognized increased from children <15 years to individuals >65 years stronger in females (P = 0.02). Antibody reactivities to GroEL, HyuA, CagM, Catalase, NapA and UreA also increased stronger in females (average 1.7-fold/decade, SD 0.5) than in males (1.5-fold/decade, SD 0.4). H. pylori antibody response accumulates qualitatively and quantitatively with age. This may reflect a lifelong stimulation of the immune response by chronically active infection.
    Preview · Article · Apr 2014 · Gut Pathogens
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    ABSTRACT: The genus beta human papillomavirus 8 (HPV8) is involved in the development of cutaneous squamous cell carcinomas (SCCs) in individuals with epidermodysplasia verruciformis. Immunosuppressed transplant recipients are prone to harbor particularly high betapapillomavirus DNA loads, which may contribute to their highly increased risk of SCC. Tumor induction in HPV8 transgenic mice correlates with increased expression of viral oncogenes E6 and E2. In an attempt to prevent skin tumor development, we evaluated an HPV8-E6-DNA vaccine, which was able to stimulate a detectable HPV8-E6-specific cell-mediated immune response in 8/15 immunized mice. When skin of HPV8 transgenic mice was grafted onto non-transgenic littermates, the grafted HPV8 transgenic tissue was not rejected and papillomas started to grow within 14 days all over the transplant of 9/9 non-vaccinated and 7/15 not successfully vaccinated mice. In contrast, no papillomas developed in 6/8 successfully vaccinated mice. In the other two of these eight mice, a large ulcerative lesion developed within the initial papilloma growth or papilloma development was highly delayed. As the vaccine completely or partially prevented papilloma development without rejecting the transplanted HPV8 positive skin, the immune system appears to attack only keratinocytes with increased levels of E6 protein, which would give rise to papillomas.
    No preview · Article · Jan 2014 · Medical Microbiology and Immunology
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    ABSTRACT: Judging the carcinogenicity of human papillomavirus (HPV) types rarely found in cervical cancer (CxCa) is hindered by lack of studies of their biological activity in cancer tissues. To asses transcriptional activity of HPV types, we have developed ultra-short amplimer, splice-site specific, E6*I mRNA RT-PCR assays for 12 high-risk (HR)-HPV (IARC Group 1) and eight probable/possible high-risk (pHR)-HPV types (IARC Group 2A/B carcinogens). Previously unreported E6*I splice sites of the six pHR-HPV types 26, 53, 67, 70, 73 and 82 were identified by cloning and sequencing. We analyzed 97 formalin-fixed paraffin-embedded (FFPE) Mongolian CxCa biopsies for presence of HPV DNA by two sensitive genotyping assays, for E6*I transcripts of all HR-/pHR-HPV types identified and for expression of HPV surrogate markers p16(INK4a) , pRb and p53. E6*I of at least one HR-/pHR-HPV was expressed in 94 (98%) of cancer tissues including seven with pHR-HPV types 26, 66, 70 or 82 as single transcribed types. Fifty-eight of E6*I mRNA transcribing cases were analyzable by immunohistochemistry and displayed p16(INK4a) overexpression in 57 (98%), pRb downregulation in 56 (97%) and p53 downregulation in 36 (62%) tissues. The newly developed E6*I mRNA RT-PCR assays appeared to be highly sensitive method to analyze HPV transcription in FFPE materials. Our finding of viral oncogene transcription of pHR-HPV types 26, 66, 70 and 82 in cervical tumors, in the absence of any other transcriptionally active HR-type and with p16(INK4a) overexpression and pRb downregulation, may support a reassessment of the carcinogenicity classification of these pHR-HPV types.
    Full-text · Article · Jan 2013 · International Journal of Cancer
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    ABSTRACT: Many findings support a possible involvement of a subgroup of human papillomaviruses (HPVs), called cutaneous beta HPV types, in the development of non-melanoma skin cancer (NMSC). The skin of transgenic (Tg) mice expressing viral oncoproteins E6 and E7 from different cutaneous beta HPV types, including HPV38, showed an increased susceptibility to UV-induced and/or chemically induced skin carcinogenesis compared with wild-type animals. In this study, we show that beta HPV38 E6 and E7 oncoproteins act as promoter and progression factors in multi-stage skin carcinogenesis, strongly cooperating with the initiator and DNA damage agent 7,12-dimethylbenz[a]anthracene (DMBA). In contrast, exposure of HPV38 E6/E7 Tg mice to the promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) did not significantly result in the development of skin lesions. These findings further support the role of beta HPV types in skin carcinogenesis, providing additional insight into their precise contribution to the multi-step process.
    Full-text · Article · Dec 2012 · Journal of General Virology
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    Andreas M Kaufmann · Lutz Gissmann · Achim Schneider

    Full-text · Article · Sep 2012 · Cancer Epidemiology Biomarkers & Prevention
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    ABSTRACT: The human papillomavirus (HPV) minor capsid protein L2 is a promising candidate for a broadly protective HPV vaccine yet the titers obtained in most experimental systems are rather low. Here we examine the potential of empty AAV2 particles (AAVLPs), assembled from VP3 alone, for display of L2 epitopes to enhance their immunogenicity. Insertion of a neutralizing epitope (amino acids 17-36) from L2 of HPV16 and HPV31 into VP3 at positions 587 and 453, respectively, permitted assembly into empty AAV particles (AAVLP(HPV16/31L2)). Intramuscularly vaccination of mice and rabbits with AAVLP(HPV16/31L2)s in montanide adjuvant, induced high titers of HPV16 L2 antibodies as measured by ELISA. Sera obtained from animals vaccinated with the AAVLP(HPV16/31L2)s neutralized infections with several HPV types in a pseudovirion infection assay. Lyophilized AAVLP(HPV16/31L2) particles retained their immunogenicity upon reconstitution. Interestingly, vaccination of animals that were pre-immunized with AAV2--simulating the high prevalence of AAV2 antibodies in the population--even increased cross neutralization against HPV31, 45 and 58 types. Finally, passive transfer of rabbit antisera directed against AAVLP(HPV16/31L2)s protected naïve mice from vaginal challenge with HPV16 pseudovirions. In conclusion, AAVLP(HPV16/31L2) particles have the potential as a broadly protective vaccine candidate regardless of prior exposure to AAV.
    Full-text · Article · Jun 2012 · PLoS ONE
  • Lutz Gissmann
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    ABSTRACT: Transmission of papillomaviruses typically occurs by direct skin-to-skin contact, and in the anogenital tract mostly by sexual intercourse. Infections often remain without symptoms and are in most instances transient depending on the human papillomavirus (HPV) type. Persistent infections with the high-risk (HR) types are the precondition for the development of a high-grade lesion and subsequently cancer, whereat the ‘transforming potential’ of HPV16, 18 and 45 is clearly distinct from the 10 other HR types. Almost all of the worldwide occurring cases of cervical cancer are related to HPV, yet in comparison to the incidence of infection, it occurs rarely and late after exposure. Other carcinomas of the anogenital tract and of the head and neck are also related to HPV (mostly HPV16), yet the fraction of positive cases is smaller.
    No preview · Chapter · Apr 2012
  • Andreas M. Kaufmann · Lutz Gissmann
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    ABSTRACT: Primary prevention by vaccination against infectious diseases and in particular viral infections has been one of the greatest successes in medicine. The two currently available prophylactic vaccines against human papillomaviruses (HPVs) consist of virus-like particles (VLPs) produced by recombinant DNA technology. Both products contain VLPs of the viruses (HPV16 and 18) that induce about 70% of the worldwide occurring cases of cervical cancer as well as a substantial fraction of malignant tumors of the vulva, penis, perianal area and oropharynx. For both vaccines, an efficacy of almost 100% against persistent infection by HPV16 and 18 and high-grade intraepithelial lesions (CIN, VIN, VaIN) was demonstrated in clinical trials with up to 8.4 years of follow-up. One of the vaccines also contains VLPs of HPV6 and 11 (‘quadrivalent vaccine’) for the prevention of genital warts (condylomata acuminata). Protection against lesions that are induced by genetically related nonvaccine types was reported most likely due to cross-neutralizing antibodies. While the natural immunity is weak and only transient, vaccination has shown to induce a sustained high immune response. Prevention of cervical cancer cases will only be seen in population-based surveys at the earliest 10 years after introduction of the vaccine. In Australia, a first success of a vaccination campaign became obvious by reduction of the incidence of genital warts. Vaccinating males is a reasonable means to reduce the risk of infection in women but it also provides them with a direct benefit through the recently documented efficacy of the quadrivalent vaccine against genital warts.
    No preview · Article · Apr 2012
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    ABSTRACT: Cervical cancer is the second most common cancer in women worldwide. Persistent high-risk human papillomavirus (HPV) infection has been identified as the causative event for the development of this type of cancer. Recombinant adeno-associated viruses (rAAVs) are currently being developed and evaluated as vaccine vector. In previous work, we demonstrated that rAAVs administered intranasally in mice induced high titers and long-lasting neutralizing antibodies against HPV type 16 (HPV16). To extend this approach to a more human-related species, we immunized rhesus macaques (Macaca mulatta) with AAVs expressing an HPV16 L1 protein using rAAV5 and 9 vectors in an intranasal prophylactic setting. An rAAV5-L1 vector followed by a boost with rAAV9-L1 induced higher titers of L1-specific serum antibodies than a single rAAV5-L1 immunization. L1-specific antibodies elicited by AAV9 vector neutralized HPV16 pseudovirions and persisted for at least 7 months post immunization. Interestingly, nasal application of rAAV9 was immunogenic even in the presence of high AAV9 antibody titers, allowing reimmunization with the same serotype without prevention of the transgene expression. Two of six animals did not respond to AAV-mediated intranasal vaccination, although they were not tolerant, as both developed antibodies after intramuscular vaccination with HPV16 virus-like particles. These data clearly show the efficacy of an intranasal immunization using rAAV9-L1 vectors without the need of an adjuvant. We conclude from our results that rAAV9 vector is a promising candidate for a noninvasive nasal vaccination strategy.
    No preview · Article · Mar 2012 · Human gene therapy

  • No preview · Conference Paper · Mar 2012
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    Preview · Article · Feb 2012 · Future Virology
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    ABSTRACT: The 27th International Papillomavirus Conference and Clinical Workshop, held in Berlin (17-22 September 2011), brought together more than 2000 scientists, clinicians and public health experts who shared new findings in the knowledge of the HPV and the prevention and treatment of HPV-related disease. In this second of three reports of the conference, the applied clinical science sessions are summarized, which focused on immunology, new HPV tests, benign HPV infections, noncervical HPV-related disease, primary and secondary prevention of cervical cancer by HPV-based screening and prophylactic HPV vaccination and treatment of HPV-induced disease. The clinical workshops discussed possible alternative schedules of prophylactic HPV vaccination, prevention of anal cancer and anal precancer, validation of HPV genotyping assays, establishment of standards and laboratory proficiency in testing for HPV DNA and anti-HPV antibodies through the WHO LabNet, and currently heavily debated questions on the role of colpo
    Preview · Article · Jan 2012 · Future Virology

Publication Stats

18k Citations
1,185.92 Total Impact Points

Institutions

  • 1985-2015
    • German Cancer Research Center
      • • Division of Genome Modifications and Carcinogenesis
      • • Research Program Infection and Cancer
      Heidelburg, Baden-Württemberg, Germany
  • 2009-2014
    • King Saud University
      • Department of Botany and Microbiology
      Ar Riyāḑ, Ar Riyāḑ, Saudi Arabia
  • 1999-2009
    • Universität Heidelberg
      Heidelburg, Baden-Württemberg, Germany
    • Friedrich Schiller University Jena
      • Clinic of Obstetrics and Gynecology
      Jena, Thuringia, Germany
  • 2006
    • Deutsches Zentrum für Infektionsforschung DZIF
      Brunswyck, Lower Saxony, Germany
  • 1994-2000
    • Loyola University Medical Center
      • Department of Obstetrics and Gynecology
      Maywood, Illinois, United States
  • 1998
    • Mexican Institute of Social Security
      Ciudad de México, The Federal District, Mexico
  • 1997
    • Loyola University Chicago
      • Department of Microbiology and Immunology
      Chicago, Illinois, United States
  • 1996
    • Loyola University
      New Orleans, Louisiana, United States
  • 1995
    • University of Texas MD Anderson Cancer Center
      • Department of Thoracic Cardiovascular Surgery
      Houston, Texas, United States
  • 1993
    • Sinai Hospital
      Detroit, Michigan, United States
    • Leiden University Medical Centre
      • Department of Dermatology
      Leiden, South Holland, Netherlands
  • 1992
    • Freie Universität Berlin
      Berlín, Berlin, Germany
  • 1991
    • Aarhus University
      Aarhus, Central Jutland, Denmark
  • 1989
    • University of Sydney
      Sydney, New South Wales, Australia
  • 1987-1989
    • Universität Ulm
      • Clinic of Gynecology and Obstetrics
      Ulm, Baden-Württemberg, Germany
  • 1986
    • National Cancer Center, Japan
      Edo, Tōkyō, Japan
    • Beatson Institute for Cancer Research
      Glasgow, Scotland, United Kingdom
  • 1979-1985
    • University of Freiburg
      • Institute of Hydrology (IHF)
      Freiburg, Baden-Württemberg, Germany
    • University of Queensland
      Brisbane, Queensland, Australia
  • 1982
    • Hannover Medical School
      Hanover, Lower Saxony, Germany
  • 1978
    • Justus-Liebig-Universität Gießen
      • Institut für Virologie
      Giessen, Hesse, Germany