Contenuti

Infectious Causes of Human Cancer

8 April 2019. 
Harald zur Hausen, German Cancer Institute
, Heidelberg.

The 2018/19 M Fraccaro lecture will be given by Harald zur Hausen of the German Cancer Institute in Heidelberg in the main University lecture hall (Aula Magna) in Strada Nuova on the 8th of April at 5.00 pm and is entitled: Infectious Causes of Human Cancer. The lecture is organised on an annual basis jointly by Collegio A Volta and Collegio Cairoli where M Fraccaro served as a College Director for nearly 35 years. The poster of the lecture can be downloaded here. H zur Hausen made seminal contributions to the discovery of infectious agents causing human cancers through his pioneering work on Human Papilloma Viruses (HPV) and their roles as  causal agents of cervical cancer and several other types of tumours. H zur Hausen's work led to the development of an HPV vaccine which is widely and successfully used in order to prevent HPV infection and thus cancer.  For this work H zur Hausen was awarded the Nobel Prize for Physiology or Medicine in 2008.


Abstract

The growth, division, and death of living cells are regulated by their genes. If these functions are out of balance, tumors can form. One reason for this may be the incorporation of virus genes into the genes of host cells. Harald zur Hausen demonstrated in 1983 that cervical cancer in humans is caused by certain types of papilloma viruses (wart viruses), the genes from which are incorporated into the host cells' DNA. This discovery made it possible to develop a vaccine against cervical cancer, which had been the second most common tumor disease in women.

Biography
From Les Prix Nobel. The Nobel Prizes 2008, Editor Karl Grandin, [Nobel Foundation], Stockholm, 2009 (https://www.nobelprize.org/prizes/medicine/2008/hausen/biographical/)


Born in 1936, I experienced the Second World War as a child in the city of Gelsenkirchen-Buer. This area was heavily bombed, but fortunately all members of my family survived the war and post-war period. As a child I remember my own intensive interest in biology, birds, other animals and flowers and was determined at an early age to become a scientist. Since schools were closed due to the bombing raids in 1943, my elementary school training was full of gaps. When I entered “Gymnasium” at the age of 10 in 1946, during the first year these gaps were evident and created some difficulties for me. After the first year there, however, although not being the top pupil, I went to school without any major problems. In 1950 my parents moved to Northern Germany where I finished high school in 1955 with the “Abitur”.

After briefly considering whether to study biology or medicine, I opted for medicine and initiated my studies at the University of Bonn. The first two years were particularly hard, since I simultaneously decided to attend lectures and courses in biology as well. The first examination after 5 semesters (“Physikum”) was passed without any problems with remarkably good grades. This created some self-confidence for the forthcoming semesters, which I spent at the University of Hamburg for one year and the (at that time) Medical Academy in Düsseldorf. At the end of 1960 I graduated there in medicine and also finished my MD thesis.

Although I remained firmly determined to continue in science, I wanted to receive a licence to practice medicine. This required at that time two years of medical internship. It brought me for short periods of time into surgery, internal medicine and for the remaining time into gynaecology and obstetrics. The last part fascinated me tremendously, although it turned out to be physically highly demanding. When I left the hospital and started to work in Medical Microbiology and Immunology at the University of Düsseldorf, for the first and only time I had some doubts whether this was the correct decision. For a short while I considered returning to the life of a practising physician; after a couple of months, however, I became more fascinated by early experimental studies. Initially I started to work on virus-induced chromosomal modifications and at the same time received relatively solid training in diagnostic bacteriology and virology, both of them at that time in an early stage of development.

During my 3½ years in Düsseldorf, I became increasingly aware of the limitations in my scientific education and decided to search for a postdoctoral position elsewhere, preferably in the United States. I received an interesting offer from Werner and Gertrude Henle at the Children’s Hospital of Philadelphia, where Werner headed the Division of Virology. In 1964 I got married and our first son Jan Dirk arrived one year later. Within the same year we decided to accept the offer from Philadelphia; in the end of December 1965 I arrived there and started work at the beginning of 1966.

The Henle’s laboratory was deeply interested in the newly discovered Epstein-Barr virus (EBV), and the whole team was actively engaged in developing serological tests for this virus and in studying its epidemiology. They had noted early that Burkitt’s lymphoma patients developed high antibody titres against viral antigens. I felt very much compelled to work with this agent, but noted at the same time my lack of familiarity with the rapidly developing molecular biological methods. I urged Werner Henle to permit me to work with a different agent, namely adenovirus type 12, hoping that this relatively well established system would permit me to become acquainted with molecular methods. He reluctantly agreed. I started to work eagerly on the induction of specific chromosomal aberrations in adenovirus type 12-infected human cells, simultaneously studying a DNA-replication disturbance of individual chromosomes in human lymphoblastoid and lymphoma cell lines, and, to please my mentor, I demonstrated electron microscopically the presence of EBV particles directly in individual serologically antigen-positive Burkitt’s lymphoma cells. During my years in Philadelphia the immortalising function of EBV was demonstrated for human B-lymphocytes, and the role of this virus as a causative agent of infectious mononucleosis was conclusively established.

In 1968 I received an attractive offer from Eberhard Wecker, who headed the newly opened Institute for Virology at the University of Würzburg, Germany. He offered me the establishment of my own independent group and granted me his support for a quick start in the German academic system. I accepted this offer and moved with my family in March 1969 back to Germany. Here I decided to change my topics completely to EBV research. The intention was to prove that EBV DNA persists in every tumour cell of Burkitt’s lymphoma and does not establish a persistent infection there, as assumed at that time by a number of my former colleagues. With the aid of Werner Henle in Philadelphia and George Klein in Stockholm I received a large number of Burkitt’s lymphoma cell lines and tumour biopsies. The biopsies also included material from nasopharyngeal carcinomas, where serological assays also suggested an involvement of EBV infections.

The major problem, the purification of sufficient quantities of EBV DNA from a low number of spontaneously virus-producing cells, was quickly solved. By the end of 1969 I had the first data available that the non-EBVproducing Burkitt’s lymphoma cell line Raji contained multiple copies per cell of EBV DNA. Shortly thereafter it was also possible to demonstrate EBV DNA in Burkitt’s lymphoma and nasopharyngeal cancer biopsies. It seems that this was the first demonstration of persistent tumour virus DNA in human malignancies.

In nasopharyngeal carcinomas, composed of a mixture of epithelial tumour cells and lymphocytic infiltrates, it was intensively discussed whether the EBV DNA might rest in the lymphocytic infiltrates. By using in-situ hybridisations, in 1973 we were able to document the presence of EBV DNA in the epithelial tumour cells.

In 1972 I was appointed chairman of the newly established Institute of Clinical Virology in Erlangen-Nürnberg. With the move to this city I planned to change my scientific direction. Cervical cancer had long been suspected of being caused by an infectious agent. In the late 1960s Herpes simplex type 2 (HSV-2) emerged as the prime suspect based on some seroepidemiological observations. Since our previous EBV work led to the identification of EBV DNA in specific human cancers, I had asked my colleague Heinrich Schulte-Holthausen to use the same technique to search for HSV-2 sequences in cervical cancer biopsies. All attempts, however, failed.

During the previous years I had studied a large number of anecdotal reports describing malignant conversion of genital warts into squamous cell carcinomas. Since genital warts had been shown to contain typical papilloma-virus particles, this triggered the suspicion that the genital wart virus might represent the causative agent for cervical cancer. Based on this hypothesis we initiated our papillomavirus programme in Erlangen. With the aid of the local Dermatology Hospital we received a large number of wart biopsies. Viral particles could be extracted from plantar warts and in 1974 we published our first report, demonstrating a cross-hybridisation of the plantar wart virus DNA with some warts, but by far not with all of them. Genital warts and cervical cancer biopsies were negative. This was our first hint that there exist different types of papillomaviruses. In the following years our group, as well as the group around Gérard Orth in Paris, were able to identify the plurality of the human papillomavirus family by isolating a steadily increasing number of novel types.

In 1977 I was appointed as chairman of the Institute of Virology of the University of Freiburg, Germany. Most members of my group in Erlangen joined me in moving to Freiburg. Here we continued intensively our studies on human papillomaviruses.Late in 1979 my co-workers Lutz Gissmann and Ethel-Michele de Villiers successfully isolated and cloned the first DNA from genital warts, HPV-6. It was initially disappointing not to detect this DNA in cervical cancer biopsies. HPV-6 DNA, however, turned out to be helpful in isolating another closely related genital wart papillomavirus, HPV-11, initially from a laryngeal papilloma. By using HPV-11 as a probe, one out of 24 cervical cancer biopsies turned out to be positive. In addition, in other biopsies some faint bands became visible, permitting the speculation that they might represent hints of the presence of related, but different HPV types in these cancers. Two of my former students; Mathias Dürst and Michael Boshart, were asked to clone these bands. Both of them were successful. In 1983 we were able to document the isolation of HPV-16, in 1984 the isolation of HPV-18 DNA. We noted from the beginning that HPV-16 DNA was present in about 50% of cervical cancer biopsies, HPV-18 in our early experiments in slightly more than 20%, including several cervical cancer cell lines, among them the HeLa line.

Within the first two years after isolating HPVs 16 and 18 it became clear that these viruses must play an important role in cervical cancer development: viral DNA was commonly found in an integrated state, indicating the clonality of the tumour. In addition, part of the viral genome frequently became deleted in the process of integration. Two viral genes, E6 and E7, were consistently transcribed in the cancer cells. Precursor lesions of cervical cancer also contained these viruses and expressed the respective genes. Early contacts with pharmaceutical companies for the development of HPV vaccines failed, in view of a market analysis conducted by one of them which indicated that there would be no market available. Fortunately, this changed in later years.

My period in Freiburg permitted me to also work on other aspects of tumour virology: I discovered the potent activity of some phorbol esters in inducing latent Epstein-Barr virus DNA. This procedure also proved to be successful for other persistent Herpes-type viruses. In addition, I isolated a novel lymphotropic polyomavirus from African Green Monkey lymphoblasts. Up to 20% of sera from human adults also revealed neutralising antibodies to this virus. Our attempts to isolate a human correlate, however, failed. I also identified a novel adeno-associated virus, now labelled AAV-5, from my own skin scrapings. In collaboration with my colleague Jörg Schlehofer, we were also able to demonstrate that herpes simplex virus, but also other herpes-, adeno-, and vaccinia virus infections of polyoma- or papillomavirus DNA harbouring cells, resulted in amplification of the DNA of the latter. The early hypothesis that cervical cancer was caused by papillomaviruses, the successful isolation and characterisation of the two most frequent HPV types in this cancer and the subsequent steps leading to a better understanding of the mechanism of HPV-mediated carcinogenesis and eventually to the development of a preventive vaccine were cited as the prime reasons for awarding one half of the Nobel Prize for Medicine or Physiology to me in 2008.

In 1983 I was appointed as the Scientific Director of the German Cancer Research Centre (Deutsches Krebsforschungszentrum) in Heidelberg, a national research centre. Besides the major task of reorganising this research centre, I tried to maintain some time for laboratory research and continued jointly with Frank Rösl to analyse intracellular and extracellular control mechanisms preventing the activity of viral oncogenes in proliferating epithelial cells. In 2003, after 20 years, I retired from the scientific directorship of the German Cancer Research Centre. Subsequently, I kept a laboratory in the virus building of the Cancer Centre and continue up to now to act as Editor-in-Chief of the International Journal of Cancer. I started this commitment at the beginning of 2000. In retrospect, I have devoted my scientific life mainly to the question to what extent infectious agents contribute to human cancer, trusting that this will contribute to novel modes of cancer prevention, diagnosis and hopefully later on also to cancer therapy. I am of course pleased to see that at least part of this programme has been successful. I am grateful to a large number of my former co-workers, who skilfully contributed to the programme. In addition, I most gratefully acknowledge the contributions of my wife, Ethel-Michele de Villiers, who is also a scientist and tumour virologist, for her never-ending support.

Image
Cells from the uterine cervix of a patient with severe dysplasia. Image courtesy of the University of Copenhagen.

 

The Hiv-1 Tat Vaccine

11th April 2019.  
Barbara Ensoli, Istituto Superiore di Sanità, Rome

On the 11th of April 2019 Barbara Ensoli, of the Istituto Superiore di Sanità, will give a seminar entitled Vaccines: The Hiv-1 Tat Vaccine at 10.30 am in Lecture Theatre 7 of Polo didattico di Ingegneria.  In her talk B Ensoli will review the history and challenges of Hiv-1 vaccine research and will focus on her own work on the development of a therapeutic vaccine targeting Hiv-1 Tat. The poster of the lecture can be downloaded here. All College students are warmly invited to participate.

Abstract
Although antiretroviral therapy (ART) has radically changed the quality and expectancy of life of HIV-infected individuals, it is unable to fully restore the immune system and is ineffective on the viral reservoirs. Moreover, even under fully successful therapy, viral gene products are still produced. As a result, chronic inflammation and immune dysregulation persist, leading to a much higher risk of co-morbidities and death as compared to the general population, particularly in patients starting ART with very low CD4+ T-cell counts or poorly compliant to therapy. Furthermore, cumulative effects of drug toxicity cannot be mitigated through structured drug-free periods, in fact, virus rebound occurs within few weeks upon therapy interruption owing to persistency of viral reservoirs during ART. There is, therefore, a great need of novel HIV/AIDS treatments to offset ART shortfalls and to intensify treatment outcomes. A therapeutic HIV vaccine, in conjunction with existing strategies, may represent a relevant, cost-effective contribution to increase ART effectiveness by i) attaining a faster/more effective response to therapy (ART intensification), ii) mitigating the effect of poor adherence to ART, and by iii) reducing virus reservoirs. Targeting Tat represents a pathogenetic intervention against a viral product that plays major roles in virus replication, reactivation and immune dysregulation. In fact, Tat is produced very early upon infection, is released extracellularly and accumulates in tissues where it exerts effects on both the virus and the immune system making it an optimal candidate for therapeutic immunization and ART intensification. In particular, extracellular Tat activates virus and cellular gene expression and replication, contributing to disease maintenance under ART (1). Furthermore, Tat is key for virus reservoirs maintenance. In fact, by binding Env spikes on virus particles, Tat, which is produced also under ART, shields Env from neutralizing antibodies (Abs), while favouring integrin-mediated virus entry and infection of dendritic cells (DC) and T cells, key virus reservoirs. Notably anti-Tat Abs, which are infrequently produced upon natural infection, restore HIV neutralization (2). Intriguingly, epidemiological evidence indicates that the presence of naturally occurring anti-Tat Abs correlates with no or slow progression to disease (3, 4). Based on this evidence, preclinical studies in small animals and nonhuman primates were conducted, showing that the Tat protein, adjuvanted or given alone, is safe, immunogenic and effective at protecting from overt infection or disease progression macaques upon experimental infection with a pathogenic SHIV, a Simian Immunodeficiency Virus (SIV) carrying HIV-1 Tat (5, 6). Then, after approval for human use by the regulatory agencies, the Tat vaccine moved forward to clinical testing. After the successful completion of randomized, placebo-controlled, phase I trials with the biologically active HIV-1 Tat protein (7-9), an “exploratory” multicenter, randomized, open label phase II therapeutic trial was conducted in Italy in 168 anti-Tat Ab negative, virologically suppressed ART-treated patients (ISS T-002, Clinicaltrials.gov NCT00751595) to evaluate the immunogenicity (primary endpoint) and safety (secondary endpoint) of two Tat protein doses (7.5 or 30 µg) administered intradermally 3 times (3x) or 5x, one month apart (10, 11). All four vaccine regimens were safe and well-tolerated, and induced anti-Tat Abs in most patients (79%), with the highest frequency, titers, breath and durability in the Tat 30 μg groups (89% responders), particularly when given 3 times (92% responders). Most importantly, Tat immunization promoted a durable and significant increase of T, B, natural killer (NK) cells, CD4+ and CD8+ central memory subsets and of adaptive T-cell responses, with a decrease of immune activation and effector memory T-cell subsets. Moreover, a significant increase of NK cells and CD38+HLA-DR+CD8+ T cells, a phenotype associated with increased killing activity in elite controllers, was observed in the 30 μg, 3x group. Of note, therapeutic effects were greater in immune-compromised individuals. Finally, a reduction of proviral DNA was seen after week 72, particularly under HIV protease inhibitors (PI)-based regimens and with Tat 30 μg given 3 times (30 μg, 3x). This decay was significantly associated with anti-Tat Ab titers and neutralization of Tat-mediated entry of oligomeric Env in DC, which predicted at 48 weeks the significant HIV-1 DNA reduction observed since year 3 post-vaccination. None of these changes were observed in subjects on effective cART enrolled in a parallel observational study (ISS OBS T-002) used as reference control group (ClinicalTrials.gov NCT01024556). A randomized, double-blind, placebo-controlled phase II clinical trial conducted in South Africa confirmed the previous phase II exploratory study conducted in Italy in terms of safety, and induction of durable, high titers anti-Tat Abs of different classes capable of cross-clade recognition and neutralization (12). The study results also confirmed the significant increases of CD4+ T cells, above cART therapeutic levels, particularly in subjects with low CD4+ T-cell counts at baseline (low immunological responders), while proviral DNA is currently under analysis in a follow-up study. The ISS T-002 clinical trial in Italy was completed at 48 weeks; however, at study closure follow-up data were available up to 96 weeks for 76 volunteers, and up to 144 weeks for 45 volunteers. To further extend the follow-up, an observational study (ISS T-002 EF-UP, ClinicalTrials.gov NCT02118168) was conducted in 92 volunteers to evaluate the persistence of anti-Tat immune response and to monitor immunological and virological parameters, including CD4+ T-cell counts and HIV proviral DNA load in vaccinees (13). The results of the 8-year extended follow-up study confirms the durability of specific humoral responses, which were still detectable after 8 years in about 50% of the vaccinees in the Tat 30 µg regimens, and shows a long-lasting (up to 8 years) stabilization of CD4+ T-cell increases, with a net average gain of about 100 cells/μL. Of note, CD4+ T-cell count restoration occurred even in subjects with a CD4+ T-cell nadir ≤250 cells/µL and even in poor immunological responders to ART (i.e. <500 CD4+ T-cells/µL at baseline), who are known to experience disease progression and comorbidities.
A striking finding of this study is represented by the continued HIV DNA decay that, in vaccinees of the 30 μg 3x regimen, was reduced by 90% after 8 years from vaccination. This, in fact, conflicts with the known stabilization after about 4 years of ART of HIV DNA into a residual, steady reservoir core, as also observed by us in the reference control group of our trial. Notably, the rate kinetics of HIV DNA decay in Tat vaccinees appeared to be generally much faster (3 years) as compared to patients on effective ART for comparable period of times (7-19 years). These data suggest that Tat immunization accelerates latent HIV reservoir decay in ART-treated patients.  The Tat vaccinees also experienced an increase of the CD4+/CD8+ T-cell ratio, an important marker of immune reconstitution in virologically suppressed ART-treated patients reported to correlate inversely with the size of virus reservoir. In their whole, these data suggest that anti-Tat immune responses can compensate for ART shortfalls and promote return to immune homeostasis, which likely contributes to restoration of effective antiviral responses that, together with anti-Tat immunity, are capable of attacking ART-resistant virus reservoirs. Thus, Tat immunization represents a promising pathogenesis-driven intervention to intensify ART efficacy while renewing perspectives for a functional cure. Future therapy interruption studies will provide proof-of-concept that Tat vaccine recipients may be able to stay off therapy safely for periods of time to be determined in ad hoc trials in Italy. At the same time phase III studies have been planned in South Africa for vaccine registration in patients just initiated to therapy as well as in poor immunological responders therapy.

Biography
Barbara Ensoli is Director of the National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy  She graduated in Medicine and Surgery and specialized in Clinical Immunology and Allergy at the University of Rome La Sapienza, Italy. She then spent more than 10 years at the National Institute of Health (Bethesda, Maryland, USA), working at the National Cancer Institute. During those years she elucidated the role of the HIV-1 Tat protein in HIV pathogenesis and AIDS-associated tumors. Her current research interests are HIV pathogenesis and the development of HIV/AIDS preventative and therapeutic vaccines, which are currently in advanced clinical phase. She has coordinated several international and national research programs in Europe and Developing countries. Among them, the EU-funded "AIDS Vaccine Integrated Project" (AVIP) and the “Program to support the Ministry of Health of South Africa in the implementation of a national program of global response to HIV & AIDS” (Italian Ministry of Foreign Affairs). She is a member of the European Molecular Biology Organisation (EMBO) and of the Editorial Board of the Health Status Report. She has been member of the WHO-UNAIDS Vaccine Advisory Committee, Vice-President of the National AIDS Committee of the Italian Ministry of Health (2006-2015) and of the ERC Scientific Council (2013-2016). She has received many national and international awards and authored more than 340 publications in peer-reviewed journals. She is named as an inventor in 7 patents.

Reference
[01].    Cafaro, A., Sgadari, C., Picconi, O., Tripiciano, A., Moretti, S., Francavilla, V., et al. (2017). "cART intensification by the HIV-1 Tat B clade vaccine: progress to phase III efficacy studies". Expert Review of Vaccines, 1–12. http://doi.org/10.1080/14760584.2018.1418666

[02].    Monini, P., Cafaro, A., Srivastava, I. K., Moretti, S., Sharma, V. A., Andreini, C., et al. (2012). HIV-1 Tat Promotes Integrin-Mediated HIV Transmission to Dendritic Cells by Binding Env Spikes and Competes Neutralization by Anti-HIV Antibodies. PLoS ONE, 7(11), e48781. http://doi.org/10.1371/journal.pone.0048781

[03].    Rezza, G., Fiorelli, V., Dorrucci, M., Ciccozzi, M., Tripiciano, A., Scoglio, A., et al. (2005). The presence of anti-Tat antibodies is predictive of long-term nonprogression to AIDS or severe immunodeficiency: findings in a cohort of HIV-1 seroconverters. The Journal of Infectious Diseases, 191(8), 1321–1324. http://doi.org/10.1086/428909

[04].    Bellino, S., Tripiciano, A., Picconi, O., Francavilla, V., Longo, O., Sgadari, C., et al. (2014). The presence of anti-Tat antibodies in HIV-infected individuals is associated with containment of CD4+ T-cell decay and viral load, and with delay of disease progression: results of a 3-year cohort study. Retrovirology, 11, 49. http://doi.org/10.1186/1742-4690-11-49

[05].    Cafaro, A., Caputo, A., Fracasso, C., Maggiorella, M. T., Goletti, D., Baroncelli, S., et al. (1999). Control of SHIV-89.6P-infection of cynomolgus monkeys by HIV-1 Tat protein vaccine. Nature Medicine, 5(6), 643–650. http://doi.org/10.1038/9488

[06].    Cafaro, A., Bellino, S., Titti, F., Maggiorella, M. T., Sernicola, L., Wiseman, R. W., et al. (2010). Impact of viral dose and major histocompatibility complex class IB haplotype on viral outcome in mauritian cynomolgus monkeys vaccinated with Tat upon challenge with simian/human immunodeficiency virus SHIV89.6P. Journal of Virology, 84(17), 8953–8958. http://doi.org/10.1128/JVI.00377-10

[07].    Ensoli, B., Fiorelli, V., Ensoli, F., Lazzarin, A., Visintini, R., Narciso, P., et al. (2008). The therapeutic phase I trial of the recombinant native HIV-1 Tat protein. AIDS (London, England), 22(16), 2207–2209. http://doi.org/10.1097/QAD.0b013e32831392d4

[08].    Longo, O., Tripiciano, A., Fiorelli, V., Bellino, S., Scoglio, A., Collacchi, B., et al. (2009). Phase I therapeutic trial of the HIV-1 Tat protein and long term follow-up. Vaccine, 27(25-26), 3306–3312. http://doi.org/10.1016/j.vaccine.2009.01.090

[09].    Ensoli, B., Fiorelli, V., Ensoli, F., Lazzarin, A., Visintini, R., Narciso, P., et al. (2009). The preventive phase I trial with the HIV-1 Tat-based vaccine. Vaccine, 28(2), 371–378. http://doi.org/10.1016/j.vaccine.2009.10.038

[10].    Ensoli, B., Bellino, S., Tripiciano, A., Longo, O., Francavilla, V., Marcotullio, S., et al. (2010). Therapeutic immunization with HIV-1 Tat reduces immune activation and loss of regulatory T-cells and improves immune function in subjects on HAART. PLoS ONE, 5(11), e13540. http://doi.org/10.1371/journal.pone.0013540

[11].    Ensoli, F., Cafaro, A., Casabianca, A., Tripiciano, A., Bellino, S., Longo, O., et al. (2015). HIV-1 Tat immunization restores immune homeostasis and attacks the HAART-resistant blood HIV DNA: results of a randomized phase II exploratory clinical trial. Retrovirology, 12, 33. http://doi.org/DOI 10.1186/s12977-015-0151-y

[12].    Ensoli, B., Nchabeleng, M., Ensoli, F., Tripiciano, A., Bellino, S., Picconi, O., et al. (2016). HIV-Tat immunization induces cross-clade neutralizing antibodies and CD4+ T cell increases in antiretroviral-treated South African volunteers: a randomized phase II clinical trial. Retrovirology, 13(1), 1250. http://doi.org/10.1186/s12977-016-0261-1

[13].    Sgadari, C., Monini, P., Tripiciano, A., Picconi, O., Casabianca, A., Orlandi, C., et al. (2019). Continued Decay of HIV Proviral DNA Upon Vaccination With HIV-1 Tat of Subjects on Long-Term ART: An 8-Year Follow-Up Study. Frontiers in Immunology, 10, 233. http://doi.org/10.3389/fimmu.2019.00233



 

Vaccines: Are they worth a shot

26th March 2019.  
Andrea Grignolio, San Raffaele University, Milan and ITB-CNR, Rome

On the 26th of March 2019 Andrea Grignolio, of Università San Raffaele, will give a seminar entitled Vaccines: Are they worth a shot at 3.00 pm in Lecture Theatre 7 of Polo didattico di Ingegneria.  In his talk A Grignolio will highlight that vaccine controversies are as old as vaccines themselves and will discuss the factors that have widened and deepened current skepticism about vaccines in large sections of the western world.  Most importantly, A Grignolio will put forward his views on how to search for common ground and a common language between scientists and skeptics thus overcoming the current vaccine crisis. The poster of the lecture can be downloaded here. All College students are warmly invited to participate.

Abstract
The dangerous decline in vaccinations in many developed countries is at the heart of a lively debate that confirms how important the subject is today. Vaccinations are among mankind’s most important scientific discoveries, yet they continue to be viewed with suspicion by part of the public – the victims of disinformation campaigns, instrumentalization and unfounded fears. There is, however, also an evolutionary explanation for these irrational beliefs, and countering the growing social opposition will be extremely difficult without grasping it. This book, which sheds new light on the safety and importance of vaccinations, is intended both for parents and those readers who want to understand the role of vaccinations in contemporary society, where the ease of access to knowledge is both a great opportunity and a great responsibility. The chapters follow a historical progression and conclude with a discussion of the most recent cognitive theories on how to overcome this opposition to vaccinations.

Biography
Andrea Grignolio
, holds a PhD in History of Science and teaches History of Medicine and Bioethics at Vita-Salute S Raffaele University of Milan and at ITB-CNR. He studied at the Centre Cavaillès of École Normale Supérieure in Paris (2004), was a post-doctoral fellowship at the Center for Philosophy and History of Science at Boston University (2006-2007), visiting scholar at the Office for History of Science and Technology at UC Berkeley (2009), and ARD2020 Research Fellow at the University François-Rabelais of Tours, France (2016-17). He is the author of papers appeared on international journals and his book Vaccines: Are they Worth a Shot ? (Springer 2018), translated in 4 languages, reached the final selection of the two most important Italian prizes for Public awareness of science. Public understanding of science remains one of his favourite subjects. He writes for the Italian newspaper La Repubblica.

Reference
[1] A Grignolio. Vaccines: Are they worth a shot. Springer Copernicus (2018)

Photography

A basic photography course is offered to College students starting from 2018/19.  Photography is not only one of man's most effective way to capture the world that surrounds us, it is also a true art form that can convey extraordinary feelings and in depth knowledge.  The photography course will be offered by the local Photography Society in Pavia, a body that collects first class photographers with an outstanding artistic record.

 Image courtesy: https://www.webindia123.com/

 

Art

A basic drawing and painting course is offered to College students starting from 2018/19.  The College is well aware that much of its work is directed to the sciences, engineering and medicine and that, as a result, active steps should be taken in order to encourage the pursue of art, music, the humanities and social sciences in College.  The art course, together with a new photography course constitute initial steps in the process of bridging the 'two cultures' at Volta.

 

 

 

Italian

In the academic year 2018/19 the College introduced the first Italian language course. This course had been long in the making because College is aware that  the University Centro linguistico offers a range of courses in Italian language.  However, a number of foreign students living and working in College have explained that the time and cost of the official courses offered bby Centro linguistico do not allow a number of them to participate, hence the College decision to offer a course of Italian language (B1 level) and culture. 

 

 

 

The 'Idea' Centre

A two-day colloquium promoted by Collegio A Volta, the University of Pavia and Scuola Normale in Pisa  will take place on the 6th and 7th of February in the College lecture theatre and will highlight a series of new research projects in the areas of Drug Discovery and Protein Engineering to be carried out under the mandate of a new Collaborative Research Centre named Idea.

The development of new therapeutics - whether small molecules or proteins  - is a complex and multistage process that involves expertises in biology, chemistry, biophysics, etc. Further, it requires considerable financial investment in order to enable adequate characterisation of the therapeutic target, screening and selection processes of the primary drug candidate, optimisation of key properties such as affinity and specificity ensuring adequate therapeutic, extensive pre-clinical testing and, finally, clinical trials in humans assessing safety and efficacy.

Both the University of Pavia and Scuola Normale in Pisa have considerable expertises in several of the above areas and have strengthened their research potential by building new research facilities and acquiring new and powerful instrumentation essential for research in Drug Discovery and Protein Engineering, These new facilities and this new nstrumentation includes high-speed compuiter clusters, both in Pavia and Pisa, extensive facilities for cell biological research (super resolution microscopes, cell analysers and cell sorters), electron microscopes for both cell and tissue analysis and for structural studies, mass and nuclear magnetic resonance spectrometers and instruments for in vivo imaging (both magnetic resonance imaging and micro computer tomography).

The colloquium will discuss ongoing and new research projects and will offer the opportunity to frame new collaborative projects in these areas between the Univetrsity of Pavia and Scuola Normale in Pisa in years to come. The poster of the colloquium can be downloaded here and all College students are warmly invited to participate. 

Image: the first crystal structure of an important class of therapeutic proteins: a monoclonal antibody (PDB accession 1IGT). 

High Mobility Group Box 1 protein orchestrates tissue regeneration via CXCR4

10th December 2018.  
Marco Bianchi, San Raffaele University, Milan

On the 10th of December 2018 Marco Bianchi, of Università San Raffaele, will give a seminar entitled High Mobility Group Box 1 protein orchestrates tissue regeneration via CXCR4 at 5.00 pm in the College lecture theatre.  In his talk ME Bianchi will discuss the signaling role of HMGB1 (High Mobility Group Box 1) protein as Damage Associated Molecular Pattern (DMAP) protein. DAMPs are molecules that are normally present inside cells, and whose extracellular presence signals that some cell has died or risks doing so. HMGB1, as the prototypical DAMP, signals tissue damage and triggers inflammation. This is a major area of research in cancer biology, crucial for understanding the somatic evolution of cancer. All College students are invited to attend, especially those reading Medicine, Biology, Biotechnology and Pharmaceutical Sciences. The poster of the lecture can be downloaded here.

Abstract
Inflammation and tissue regeneration follow tissue damage, but little is known about how these processes are coordinated.High Mobility Group Box 1 (HMGB1) is a nuclear protein that, when released on injury, triggers inflammation. Remarkably, extracellular HMGB1 recruits inflammatory cells when it is fully reduced, and activates them when a disulfide bond forms between two cysteines. We have now found that fully reduced HMGB1 is also involved in tissue regeneration: it orchestrates muscle and liver regeneration via CXCR4 receptor, whereas disulfideHMGB1 and its receptors TLR4/MD-2 and RAGE (receptor for advanced glycation end products) are not involved. Injection of HMGB1 accelerates tissue repair by acting on resident muscle stem cells, hepatocytes, and infiltrating cells. The nonoxidizable HMGB1 mutant 3S, in which serines replace cysteines, promotes muscle and liver regeneration more efficiently than the wildtype protein and without exacerbating inflammation, by selectively interacting with CXCR4. Overall, our results show that the reduced form of HMGB1 coordinates tissue regeneration and suggest that 3S may be used to safely accelerate healing after injury in diverse clinical contexts.

Biography
ME Bianchi graduated in Biology at the Università di Milano in 1980, and soon after moved to Yale University, joining the Radding lab and studying molecular aspects of recombination catalyzed by RecA, a bacterial protein. On returning to the Università di Milano in 1983, he started looking for equivalent proteins in eukaryotes. This work blossomed when he moved in 1986 to the EMBL in Heidelberg, as an independent Staff Scientist: he isolated a protein that bound Holliday junctions, recombination intermediates formed by DNA molecules swapping helices. After joining the University of Pavia as an Associate Professor in 1989, he showed that this protein, HMGB1, was the founding member of so called “architectural proteins” that distort and bend DNA as chaperone to promote the assembly of multiprotein-DNA complexes. Since 1992 he is at San Raffaele, where he is currently a Professor of Molecular Biology, and where he identified HMGB1 as the first DAMP, a class of molecules that had been predicted by the dogma-changing “Danger Theory” of immunology.

Reference
[1] Tirone M, Tran NL, Ceriotti C, Gorzanelli A, Canepari M, Bottinelli R, Raucci A, Di Maggio S, Santiago C, Mellado M, Saclier M, François S, Careccia G, He M, De Marchis F, Conti V, Ben Larbi S, Cuvellier S, Casalgrandi M, Preti A, Chazaud B, Al-Abed Y, Messina G, Sitia G, Brunelli S, Bianchi ME* and Vénéreau E* (2018) High Mobility Group Box 1 orchestrates tissue regeneration via CXCR4. J Exp Med 215: 303-18.  doi: 10.1084/jem.20160217.
[2] Bianchi ME, Crippa MP, Manfredi AA, Mezzapelle R, Rovere Querini P and Venereau E (2017) High Mobility Group Box 1 protein orchestrates responses to tissue damage via inflammation, innate and adaptive immunity, and tissue repair. Immunol Rev 280: 74-82. doi: 10.11

Image
Immunofluorescence of skeletal muscle, one of the targets of the HMGB1-CXCR4 signalling pathway.

MYC-dependent dynamics of transcriptional regulation

26th November 2018.  
Mattia Pelizzola, Italian Institute of Technology, Milan

On the 26th of November 2018 Mattia Pelizzola of the Italian Institute of Technology branch in Milan will give a seminar entitled MYC-dependent dynamics of transcriptional regulation at 2.00 pm in the College lecture theatre.  In his talk M Pelizzola will discuss extensive studies from his laboratory that have enabled in depth understanding of the complex gene dynamics and regulation enabled by the transcription factor Myc, the product of the MYC proto-oncogene and a master regulator of cell proliferation.  All College students are invited to attend, especially those reading Medicine, Biology, Biotechnology and Pharmaceutical Sciences. The poster of the lecture can be downloaded here.

Abstract
Overexpression of the MYC transcription factor causes its widespread interaction with regulatory elements in the genome but leads to the up- and down-regulation of discrete sets of genes. The molecular determinants of these selective transcriptional responses remain elusive. Here, we present an integrated time-course analysis of RNA and RNAPII dynamics following MYC activation in proliferating mouse fibroblasts, based on chromatin immunoprecipitation, metabolic labeling of newly synthesized RNA, extensive sequencing, and mathematical modeling. Altogether, our results shed light on how overexpressed MYC alters the various phases of the RNAPII cycle, and leads to pervasive post-transcriptional regulation.

Biography
Mattia Pelizzola graduated in Biotechnology in 2001 at the Milano-Bicocca University. Following a PhD in computational biology, he spent 4 years in the States for two postdocs, first at the Yale University, and later on at the Salk Institute. In 2011 he moved back to Milan to start his own group at the Center for Genomic Science of the Italian Institute of Technology, located within the IFOM-IEO campus. His research currently focuses on the characterization of epigenomics and epitranscriptional determinants of RNA dynamics, and how these are altered in disease conditions. His group employes an interdisciplinary approach, which combines experimental and computational methods, including metabolic labelling of nascent RNA, epitranscriptome profiling and their integrative analysis through mathematical modelling.

Reference
[1] De Pretis et al. Genome Res 27:1658 (2017).

Image
Fluorescence in situ hybridisation with a Myc gene probe demonstrates amplification of the Myc gene in cancer cells.

Metabolic modulation of haematopoietic stem cells

22th November 2018.  
Nicola Vannini, Ludwig Institute, Lausanne, Switzerland

On the 22nd of November 2018 Nicola Vannini of the Ludwig Institute for Cancer Research at Lausanne will give a seminar entitled Metabolic modulation of hematopoietic stem cells at 2.00 pm in the College lecture theatre.  In his talk N Vannini will discuss new data demonstrating how metabolic modulation of haematopoietic stem cells impact on their functions. This is a newly uncovered and potentially important level of regulation of stem cells behaviour.  All College students are invited to attend, especially those reading Medicine, Biology, Biotechnology and Pharmaceutical Sciences. The poster of the lecture can be downloaded here.

Abstract
Cellular metabolism is recently emerging as a potential regulator of stem cell fate (Sahin and Depinho 2010, Suda, Takubo et al. 2011, Zhang, Khvorostov et al. 2011), constituting a crucial regulator of the HSC pool (Gan, Hu et al. 2010, Gurumurthy, Xie et al. 2010, Nakada, Saunders et al. 2010). The energy demand of quiescent HSCs relies on anaerobic glycolisis, which has to be rapidly switched to oxidative phosphorylation to enable hematopoietic differentiation (Takubo, Nagamatsu et al. 2013, Yu, Liu et al. 2013). Consistently, hematopoietic stem and progenitor cells belong to a 6-9% population of the entire bone marrow (BM), characterized by low mitochondrial activity,(Simsek, Kocabas et al. 2010) and their metabolic profiles have been associated with their localization in hypoxic regions of the BM(Parmar, Mauch et al. 2007, Simsek, Kocabas et al. 2010). Here we show that mitochondrial activity is a functional predictor of HSC engraftment both in vivo and in vitro and its modulation is capable to displace the LT-HSC/ST-HSC equilibrium in vivo by maintaining LT-HSC and increasing ST-HSC pools. Distinct hematopoietic compartments show specific increases in mitochondrial activity during commitment. Furthermore, mitochondrial activity resolves the function of stem and progenitor cells. In LKS cells (lin-cKit+Sca1+) efficient long term engraftment is retained in a subpopulation with low mitochondrial activity (TMRM low). Similarly, long and short term engraftment potential is restricted to TMRM low LKS-CD150+CD34- and LKS-CD150+CD34+ populations respectively. Considerably low mitochondrial activity discriminates HSCs retaining engraftment potential after in vitro culture. Modulation of mitochondrial metabolism in mice, supplemented with the metabolic modulator nicotinamide riboside (NR)(Canto, Houtkooper et al. 2012), increases the ST-HSC compartment which is critical in driving hematopoiesis during the short post-transplant period via mitophagy induction.  Accordingly, limiting BM transplant shows a dramatic improvement of survival in mice treated with NR compared to untreated ones, as predicted by faster platelet and neutrophil recoveries. Thus mitochondrial metabolism is a critical functional marker for LT-HSC, ST-HSC and in vitro cultured cells, and it reveals novel strategies to modulate the balance between hematopoietic compartments with possible significant clinical impact.

Biography
Nicola Vannini after his MSc degree in Biological Sciences obtained at the University of Parma, moved to La Jolla (CA) where he worked for two years at the Burnham Institute in the laboratory of Prof. John C. Reed and Prof. Giovanni Paternostro studying the metabolic basis of cardiac aging. Afterwards he moved back to Italy in order to complete his doctoral studies. In that period he worked at the National Institute for Cancer Research in Genova under the supervision of Dr. Adriana Albini and Prof. Douglas Noonan. His research topic was on the development of nutritional interventions as strategy to prevent tumor progression and angiogenesis, with particular focus on anti-inflammatory processes. After his studies Nicola Vannini has worked in the laboratory of stem cell bioengineering directed by Prof. Matthias Lütolf at the EPFL as postdoctoral fellow. There he developed a semi-automated system to analyze hematopoietic stem cell (HSC) fate at single cell level and, most recently, discovered important metabolic features regulating HSC function. In 2014 he continued his work in the laboratory of Prof. Olaia Naveiras and in collaboration with Prof. Johan Auwerx at the EPFL, where he developed targeted metabolic interventions capable to manipulate HSC fate. Since March 2016 Nicola Vannini is project leader at the Ludwig Center for Cancer Research (Lausanne branch) within the group of Prof. George Coukos. His primary research goals are the understanding of metabolic changes occurring during aging in the hematopoietic and immune compartments. Lastly he is currently developing targeted therapies that can prevent/revert the aging processes and consequently improve tumor immunotherapy and immunosurveillance. Specific interests include metabolic treatment for immunotherapy non-responders, metabolic reprogramming of myeloid biased HSC in aged and chemotherapy-treated patients, development of novel methods to boost blood reconstitution in transplanted patients and understanding the metabolic features of T cell exhaustion.

References
[1] Vannini N*, Campos V, Girotra M, Trachshel V, Rojas-Sutterlin S, Tratwal J, Ragusa S, Stefanidis E, Ryu D, Rainer PY, Nikitin G, Giger S, Semilietof A , Yersin Y, Cheng WC, Tauzin L, Pirinen E, Ratajczak J, Canto C, Sizzano F, Palini A, Petrova TV, Vanhecke D, Nahimana A, Duchosal MA, Ho PC, Deplanke B, Coukos G, Auwerx J, Lutolf MP and Naveiras O*. The NAD-booster nicotinamide riboside potently stimulates hematopoiesis through increased mitochondrial clearance. Cell Stem Cell, Under final revisions
[2] Roch A, Giger S, Girotra M, Campos V, Vannini N, Naveiras O, Gobaa S, Lutolf MP. Identification of functional artificial niches by single hematopoietic stem cell fate analyses. Nat Commun. 2017
[3] Vannini N, Girotra M, Naveiras O, Nikitin G, Campos V, Giger S, Roch A, Auwerx J, Lutolf MP. Specification of haematopoietic stem cell fate via modulation of mitochondrial activity. Nat Commun. 2016
[4] Vannini N, Roch A, Naveiras O, Griffa A, Kobel S, Lutolf MP. Identification of in vitro HSC fate regulators by differential lipid raft clustering. Cell Cycle. 2012

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