Gabriella Scarlatti
e-mail: scarlatti.gabriella AT hsr.it
website: www.sanraffaele.org
affiliation: San Raffaele Scientific Institute
research area(s): Immunity And Infection, Experimental Medicine
Course:
Basic and Applied Immunology
University/Istitution: Università Vita-Salute San Raffaele
University/Istitution: Università Vita-Salute San Raffaele
Education and training
1980: Graduated at the German School, Milan, Italy.
1987: M.D., University of Medicine and Surgery, Milan.
1991: Specialist in Pediatrics, University of Milan.
1994: Ph.D., Microbiology and Tumorbiology Center, Karolinska Institutet, Stockholm, Sweden
Position and honors
1984-88: Internal membership at the First Clinical Department of Pediatrics of the University Hospital, Milan
1988-89: Internal membership at the Center for HIV-infected Children at the First Clinical Department of Pediatrics of the University Hospital, Milan
1990-94: Ph.D. at Microbiology and Tumorbiology Center, Karolinska Institutet, Stockholm, Sweden.
1994-2002: Researcher at the Laboratory of Immunobiology of HIV, DIBIT, San Raffaele Scientific Institute, Milan, Italy
since 2001: Associate Professor in Virology at the Microbiology and Tumorbiology Center, Karolinska Institutet.
since 2002: Head, Viral Evolution and Transmission Unit, DIBIT, San Raffaele Scientific Institute, Milan.
Publications
In international Journals 88 papers of which 60 original papers and 28 reviews and workshop-report papers, besides 37 proceedings of peer-reviewed conferences. 11 publications in non-indexed journals or books. (H index = 29 and an average of 140 citations/year).
Grants
Recipient of grants from the Italian AIDS program of the Ministry of Health since 1994; from European Commission during the Framework program 5 (1993-2000), 6 (2005-2011) and 7 (2008-2012); from Gates Foundation CAVD (2007-2012) and others (UNAIDS, NIH-office of AIDS research, Italian Ministry of Education, and occasional private sponsors).
Editorial/Referee duty
Editorial board member for J. New Microbiologica, J. Translational Medicine, J. International AIDS Society, Frontiers in Immunology, HIV AIDS.
Acting as referee for the granting agencies: ANRS, European Commission, the Dutch, Italian, Spanish and Swedish AIDS research funding agencies.
Member of
- University of Tor Vergata, post graduate training in Molecular Pediatrics and Applied Biotechnologies, Rome.
- PhD school of the EUROPRISE FP6 EU funded project on "Vaccine and microbicide" network of excellence.
Pedagogic activity
Since 1996 supervised 7 graduate students and 7 PhD students, and acted as opponent or examiner for 5 thesis defenses in Italy and abroad.
1980: Graduated at the German School, Milan, Italy.
1987: M.D., University of Medicine and Surgery, Milan.
1991: Specialist in Pediatrics, University of Milan.
1994: Ph.D., Microbiology and Tumorbiology Center, Karolinska Institutet, Stockholm, Sweden
Position and honors
1984-88: Internal membership at the First Clinical Department of Pediatrics of the University Hospital, Milan
1988-89: Internal membership at the Center for HIV-infected Children at the First Clinical Department of Pediatrics of the University Hospital, Milan
1990-94: Ph.D. at Microbiology and Tumorbiology Center, Karolinska Institutet, Stockholm, Sweden.
1994-2002: Researcher at the Laboratory of Immunobiology of HIV, DIBIT, San Raffaele Scientific Institute, Milan, Italy
since 2001: Associate Professor in Virology at the Microbiology and Tumorbiology Center, Karolinska Institutet.
since 2002: Head, Viral Evolution and Transmission Unit, DIBIT, San Raffaele Scientific Institute, Milan.
Publications
In international Journals 88 papers of which 60 original papers and 28 reviews and workshop-report papers, besides 37 proceedings of peer-reviewed conferences. 11 publications in non-indexed journals or books. (H index = 29 and an average of 140 citations/year).
Grants
Recipient of grants from the Italian AIDS program of the Ministry of Health since 1994; from European Commission during the Framework program 5 (1993-2000), 6 (2005-2011) and 7 (2008-2012); from Gates Foundation CAVD (2007-2012) and others (UNAIDS, NIH-office of AIDS research, Italian Ministry of Education, and occasional private sponsors).
Editorial/Referee duty
Editorial board member for J. New Microbiologica, J. Translational Medicine, J. International AIDS Society, Frontiers in Immunology, HIV AIDS.
Acting as referee for the granting agencies: ANRS, European Commission, the Dutch, Italian, Spanish and Swedish AIDS research funding agencies.
Member of
- University of Tor Vergata, post graduate training in Molecular Pediatrics and Applied Biotechnologies, Rome.
- PhD school of the EUROPRISE FP6 EU funded project on "Vaccine and microbicide" network of excellence.
Pedagogic activity
Since 1996 supervised 7 graduate students and 7 PhD students, and acted as opponent or examiner for 5 thesis defenses in Italy and abroad.
Scientific research interests
She has been studying the pathogenic mechanisms of mother-to-child HIV-1 transmission and paediatric HIV/AIDS, introducing in the early 90ies the concept of virus phenotypic and genotypic evolution and selection during transmission.
The results of the FP5-EC sponsored "African-European Network on in utero HIV transmission" at which she participated (Lagaye, J Virol 2001; Menu, JID 1999) initiated a new research interest on alternative pathways of the virus (i.e. CD4 independent, Transcytosis), which she has now continued with a new research line investigating the role of the intestinal mucosa in delivering the virus and cross-talking with submucosal cells (Cavarelli, Retrovirology 2009). The group"s recent results support the hypothesis that dendritic cells (DCs) migrate and mediate HIV-1 transmission from the lumen through the intestinal mucosa (Cavarelli submitted). The mucosa (intestinal and vaginal), the main portal of entry of HIV-1 via all routes of transmission, is the site of major immune subversion early after infection and, thus can give important information on which B and T cell responses HIV-1 is targeting to evade. She has recently started to work on the topography, phenotype, regulation and function of the intestinal mucosal B lymphocytes; to define the compartmentalization of the humoral response in tissues compared to blood, and the distribution of Ig producing B cells and plasma cells in mucosal tissues. This interest has merged with her research line on neutralization of HIV-1 and fostered the question on the role of intestinal mucosal B cells in the response to the virus.
Indeed, viral neutralization mechanisms have been a hallmark of her research line, showing the emergence of escape in MTCT and pediatric HIV infection (Scarlatti JID 1993, Dispinseri submitted). Since 2002 she initiated an international effort NeutNet, an FP6 EC-funded project on the standardisation of HIV neutralisation assays to be used in vaccine research and clinical trials, which changed the worldwide perception on the assays to be used (Fenyo, PlosOne 2009; Polonis, Curr Opin HIV 2009; Polonis, Virology 2008). Together with WHO/UNAIDS technical working group on HIV isolation and characterization and the Gates Foundation-CAVD consortium-GHRC she leads courses and research on HIV biology and neutralization.
Since 2006 she coordinates a large effort, the Humoral Immunity Platform of the FP6-EC funded "Network of Excellence-EUROPRISE". The Network is composed of 58 partners representing more than 65 institutions from 13 European countries; it also includes three major pharmaceutical companies (GlaxoSmithKline, Novartis and Sanofi-Pasteur) involved in HIV microbicide and vaccine research. The research program covers the whole pipeline of vaccine and microbicide development from discovery to early clinical trials (Wahren, JTM 2010; Brinckman JTM 2011). The Humoral Immunity Platform coordinates 18 European partners involved in the study of humoral immune responses and the role in HIV pathogenesis. In the frame of this platform two workshop were organized in 2010 and 2011 dealing with B cell immunity and antibody responses.
Since 2008 she is coordinator of the FP7-EC project NGIN "Next generation immunogens inducing broadly reactivity neutralising antibodies": 15 European partners are devoted to develop new immunogens, adjuvants and delivery systems, to be used as vaccine against HIV-1. In specific, the strategy is based on the identification of envelopes that have successfully elicited broad Nabs in their natural hosts, which will be subjected to rational modifications with the aim of exposing cryptic conserved neutralization epitopes and permitting their efficient presentation to the immune system. As today screening for neutralising activity occurred in more than 500 subjects in early and chronic phase of the disease, and broad neutralizing activity was identified in approximately 25% of subjects. More than 1200 viral clones of these individuals were sequenced. This detailed and systematic approach gave rise to an informatic database containing genetic and functional information of the envelopes to determine the viral characteristics associated with induction of Nabs. Selected viral envelopes were expressed as trimeric soluble proteins and screened for their immunogenicity and antigenicity in mice and rabbits. These same proteins were administered in a prime boost combination with the adjuvant formulations pFlic and DDA/TDB in rabbits and recently forwarded to non human primates at CEA, Paris.
She has been studying the pathogenic mechanisms of mother-to-child HIV-1 transmission and paediatric HIV/AIDS, introducing in the early 90ies the concept of virus phenotypic and genotypic evolution and selection during transmission.
The results of the FP5-EC sponsored "African-European Network on in utero HIV transmission" at which she participated (Lagaye, J Virol 2001; Menu, JID 1999) initiated a new research interest on alternative pathways of the virus (i.e. CD4 independent, Transcytosis), which she has now continued with a new research line investigating the role of the intestinal mucosa in delivering the virus and cross-talking with submucosal cells (Cavarelli, Retrovirology 2009). The group"s recent results support the hypothesis that dendritic cells (DCs) migrate and mediate HIV-1 transmission from the lumen through the intestinal mucosa (Cavarelli submitted). The mucosa (intestinal and vaginal), the main portal of entry of HIV-1 via all routes of transmission, is the site of major immune subversion early after infection and, thus can give important information on which B and T cell responses HIV-1 is targeting to evade. She has recently started to work on the topography, phenotype, regulation and function of the intestinal mucosal B lymphocytes; to define the compartmentalization of the humoral response in tissues compared to blood, and the distribution of Ig producing B cells and plasma cells in mucosal tissues. This interest has merged with her research line on neutralization of HIV-1 and fostered the question on the role of intestinal mucosal B cells in the response to the virus.
Indeed, viral neutralization mechanisms have been a hallmark of her research line, showing the emergence of escape in MTCT and pediatric HIV infection (Scarlatti JID 1993, Dispinseri submitted). Since 2002 she initiated an international effort NeutNet, an FP6 EC-funded project on the standardisation of HIV neutralisation assays to be used in vaccine research and clinical trials, which changed the worldwide perception on the assays to be used (Fenyo, PlosOne 2009; Polonis, Curr Opin HIV 2009; Polonis, Virology 2008). Together with WHO/UNAIDS technical working group on HIV isolation and characterization and the Gates Foundation-CAVD consortium-GHRC she leads courses and research on HIV biology and neutralization.
Since 2006 she coordinates a large effort, the Humoral Immunity Platform of the FP6-EC funded "Network of Excellence-EUROPRISE". The Network is composed of 58 partners representing more than 65 institutions from 13 European countries; it also includes three major pharmaceutical companies (GlaxoSmithKline, Novartis and Sanofi-Pasteur) involved in HIV microbicide and vaccine research. The research program covers the whole pipeline of vaccine and microbicide development from discovery to early clinical trials (Wahren, JTM 2010; Brinckman JTM 2011). The Humoral Immunity Platform coordinates 18 European partners involved in the study of humoral immune responses and the role in HIV pathogenesis. In the frame of this platform two workshop were organized in 2010 and 2011 dealing with B cell immunity and antibody responses.
Since 2008 she is coordinator of the FP7-EC project NGIN "Next generation immunogens inducing broadly reactivity neutralising antibodies": 15 European partners are devoted to develop new immunogens, adjuvants and delivery systems, to be used as vaccine against HIV-1. In specific, the strategy is based on the identification of envelopes that have successfully elicited broad Nabs in their natural hosts, which will be subjected to rational modifications with the aim of exposing cryptic conserved neutralization epitopes and permitting their efficient presentation to the immune system. As today screening for neutralising activity occurred in more than 500 subjects in early and chronic phase of the disease, and broad neutralizing activity was identified in approximately 25% of subjects. More than 1200 viral clones of these individuals were sequenced. This detailed and systematic approach gave rise to an informatic database containing genetic and functional information of the envelopes to determine the viral characteristics associated with induction of Nabs. Selected viral envelopes were expressed as trimeric soluble proteins and screened for their immunogenicity and antigenicity in mice and rabbits. These same proteins were administered in a prime boost combination with the adjuvant formulations pFlic and DDA/TDB in rabbits and recently forwarded to non human primates at CEA, Paris.
1. C.Sabin, D.Corti, V. Buzon, M.S. Seaman, D. Lutje Hulsik, A. Hinz, F. Vanzetta, G. Agatic, C. Silacci, L. Mainetti, G. Scarlatti, F. Sallusto, R.A. Weiss, A. Lanzavecchia and W. Weissenhorn. Crystal structure and size-dependent neutralization properties of HK20, a human monoclonal antibody binding to the highly conserved heptad repeat 1 of gp4. PLoS Pathogens 2010 Nov 18;6(11):e1001195.
2. Cavarelli M., Karlsson I., Ripamonti C., Plebani A., Fenyo EM., G. Scarlatti G. Flexible use of CCR5 in the absence of CXCR4 use explains the immune deficiency in HIV-1 infected children. AIDS. 2010 Oct 23;24(16):2527-33.
3. Baroni M, Matucci A, Scarlatti G, Soprana E, Rossolillo P, Lopalco L, Zipeto D, Siccardi AG, De Santis C. HLA-C is necessary for optimal human immunodeficiency virus type 1 infection of human peripheral blood CD4 lymphocytes. J Gen Virol. 2010 Jan;91(Pt 1):235-41. Epub 2009 Sep 23.
4. Pornprasert, S., Mary, J.-Y., Faye, A., Leechanachai, P., Limtrakul, A., Rugpao, S., Sirivatanapa, P., Gomuthbutra, V., Matanasaravoot, W., Le C"ur, S., Lallemant, M., Barré-Sinoussi, F., Menu, E., Ngo-Giang-Huong, N., Ayouba, A., Chailert, S., Chaouat, G., Derrien, M., Dolcini, G., Eteki, N., Kfutwah, A.J., Kouo, O., Lemen, B., Maldonado-Estrada, J., Nerrienet, E., Njinku, B., Scarlatti, G., Tejiokem, M., Téné, G. for the ANRS 1267 study team and HIV-1 PMTCT-PlaNet. Higher placental anti-inflammatory IL-10 cytokine expression in HIV-1 infected women receiving longer zidovudine prophylaxis associated with nevirapine. Curr HIV Res. 2009 Mar;7(2):211-7.
5. Fenyö EM, Heath A, Dispinseri S, Holmes H, Lusso P, Zolla-Pazner S, Donners H, Heyndrickx L, Alcami J, Bongertz V, Jassoy C, Malnati M, Montefiori D, Moog C, Morris L, Osmanov S, Polonis V, Sattentau Q, Schuitemaker H, Sutthent R, Wrin T, and Scarlatti G. International Network for Comparison of HIV Neutralization Assays: the NeutNet report. PLoS ONE 2009;4(2):e4505.
6. Ceballos A, Andreani G, Ripamonti C, Dilernia D, Mendez R, Rabinovich R.D., Coll Cardenas P, Zala C, Chan P, Scarlatti G, Martinesz Peralta L. Lack of viral selection in HIV-1 mother to child transmission with primary infection during late pregnancy and/or breastfeeding. J Gen Virol. 2008; 89:2773-82.
7. Cavarelli M, Karlsson I, Zanchetta M, Antonsson L, Plebani A, Giaquinto C, Fenyö EM, De Rossi A, Scarlatti G. HIV-1 with multiple CCR5/CXCR4 chimeric receptor use is predictive of immunological failure in infected children. PLoS ONE. 2008; 3(9): e3292.
8. Malnati MS / Scarlatti G, Gatto F, Salvatori F, Cassina G, Rutigliano T, Volpi R, Lusso P. A universal real-time PCR assay for the quantification of group-M HIV-1 proviral load. Nat Protoc. 2008; 3(7): 1240-8.
9. V. Polonis, BK Brown, A Rosa Borges, S Zolla-Pazner, D S Dimitrov, M-Y Zhang, S W Barnett, R M Reprecht, G Scarlatti, E-M Fenyo, D C Montefiori, F E McCutchan, N L Michael. Recent Advances in the Characterization of HIV-1 Neutralization Assays for Standardized Evaluation of the Antibody Response to Infection and Vaccination. Virology 2008; 375(2): 315-20
10. 13. C. Ripamonti, T. Leitner, A. Laurén, I. Karlsson, A. Pastore, M. Cavarelli, L. Antonsson, A. Plebani, EM. Fenyö and G. Scarlatti. Biological and genetic evolution of HIV-1 in two siblings with different patterns of disease progression. AIDS Res and Human Retrov 2007; 23 (12): 1531-40.
REVIEWS:
1. Brinckmann S, da Costa K, van Gils MJ, Hallengärd D, Klein K, Madeira L, Mainetti L, Palma P, Raue K, Reinhart D, Reudelsterz M, Ruffin N, Seifried J, Schäfer K, Sheik-Khalil E, Sköld A, Uchtenhagen H, Vabret N, Ziglio S, Scarlatti G, Shattock R, Wahren B, Gotch F.Rational Design of HIV Vaccine and Microbicides: Report of the EUROPRISE Network Annual Conference 2010. J Translational Medicine 2011, 9:40.
2. M. Cavarelli and G. Scarlatti. HIV-1 co-receptor usage:influence on mother-to-child transmission and pediatric infection. J Translational Medicine 2011 Volume 9 Supplement 1. doi:10.1186/1479-5876-9-S1-S10.
3. A. McMichael and F. McCutchan on behalf of a Working Group convened by the Global HIV Vaccine Enterprise:Host Genetics and Viral Diversity: Report from a Global HIV Vaccine Enterprise Working Group. Nature Precedings doi:10.1038/npre.2010.4797.2.
4. B.Wahren, P. Biswas, M. Borggren, A. Coleman, K. da Costa, W. De Haes, T. Dieltjens, S. Dispinseri, K. Grupping, J. Seifried, P. Selhorst, A. Skold, H. Uchtenhagen, M. J. van Gils, C. Weber, R. Shattock and G. Scarlatti. Rational Design of HIV Vaccine and Microbicides: Report of the EUROPRISE Annual Conference. J Transl Med 2010 26;8:72.
6. A.L. Ross, A. Brave, G. Scarlatti, A. Manrique and L. Buonaguro. Progress towards development of an HIV Vaccine: a report of the AIDS Vaccine 2009 Conference. The Lancet infectious Disease 2010; 10(5): 305-316.
7. Polonis VR, Schuitemaker H, Bunnik EM, Brown BK, Scarlatti G. Impact of host cells on neutralization of HIV-1 in vitro. Curr Opin HIV AIDS. 2009;4(5):400-7.
2. Cavarelli M., Karlsson I., Ripamonti C., Plebani A., Fenyo EM., G. Scarlatti G. Flexible use of CCR5 in the absence of CXCR4 use explains the immune deficiency in HIV-1 infected children. AIDS. 2010 Oct 23;24(16):2527-33.
3. Baroni M, Matucci A, Scarlatti G, Soprana E, Rossolillo P, Lopalco L, Zipeto D, Siccardi AG, De Santis C. HLA-C is necessary for optimal human immunodeficiency virus type 1 infection of human peripheral blood CD4 lymphocytes. J Gen Virol. 2010 Jan;91(Pt 1):235-41. Epub 2009 Sep 23.
4. Pornprasert, S., Mary, J.-Y., Faye, A., Leechanachai, P., Limtrakul, A., Rugpao, S., Sirivatanapa, P., Gomuthbutra, V., Matanasaravoot, W., Le C"ur, S., Lallemant, M., Barré-Sinoussi, F., Menu, E., Ngo-Giang-Huong, N., Ayouba, A., Chailert, S., Chaouat, G., Derrien, M., Dolcini, G., Eteki, N., Kfutwah, A.J., Kouo, O., Lemen, B., Maldonado-Estrada, J., Nerrienet, E., Njinku, B., Scarlatti, G., Tejiokem, M., Téné, G. for the ANRS 1267 study team and HIV-1 PMTCT-PlaNet. Higher placental anti-inflammatory IL-10 cytokine expression in HIV-1 infected women receiving longer zidovudine prophylaxis associated with nevirapine. Curr HIV Res. 2009 Mar;7(2):211-7.
5. Fenyö EM, Heath A, Dispinseri S, Holmes H, Lusso P, Zolla-Pazner S, Donners H, Heyndrickx L, Alcami J, Bongertz V, Jassoy C, Malnati M, Montefiori D, Moog C, Morris L, Osmanov S, Polonis V, Sattentau Q, Schuitemaker H, Sutthent R, Wrin T, and Scarlatti G. International Network for Comparison of HIV Neutralization Assays: the NeutNet report. PLoS ONE 2009;4(2):e4505.
6. Ceballos A, Andreani G, Ripamonti C, Dilernia D, Mendez R, Rabinovich R.D., Coll Cardenas P, Zala C, Chan P, Scarlatti G, Martinesz Peralta L. Lack of viral selection in HIV-1 mother to child transmission with primary infection during late pregnancy and/or breastfeeding. J Gen Virol. 2008; 89:2773-82.
7. Cavarelli M, Karlsson I, Zanchetta M, Antonsson L, Plebani A, Giaquinto C, Fenyö EM, De Rossi A, Scarlatti G. HIV-1 with multiple CCR5/CXCR4 chimeric receptor use is predictive of immunological failure in infected children. PLoS ONE. 2008; 3(9): e3292.
8. Malnati MS / Scarlatti G, Gatto F, Salvatori F, Cassina G, Rutigliano T, Volpi R, Lusso P. A universal real-time PCR assay for the quantification of group-M HIV-1 proviral load. Nat Protoc. 2008; 3(7): 1240-8.
9. V. Polonis, BK Brown, A Rosa Borges, S Zolla-Pazner, D S Dimitrov, M-Y Zhang, S W Barnett, R M Reprecht, G Scarlatti, E-M Fenyo, D C Montefiori, F E McCutchan, N L Michael. Recent Advances in the Characterization of HIV-1 Neutralization Assays for Standardized Evaluation of the Antibody Response to Infection and Vaccination. Virology 2008; 375(2): 315-20
10. 13. C. Ripamonti, T. Leitner, A. Laurén, I. Karlsson, A. Pastore, M. Cavarelli, L. Antonsson, A. Plebani, EM. Fenyö and G. Scarlatti. Biological and genetic evolution of HIV-1 in two siblings with different patterns of disease progression. AIDS Res and Human Retrov 2007; 23 (12): 1531-40.
REVIEWS:
1. Brinckmann S, da Costa K, van Gils MJ, Hallengärd D, Klein K, Madeira L, Mainetti L, Palma P, Raue K, Reinhart D, Reudelsterz M, Ruffin N, Seifried J, Schäfer K, Sheik-Khalil E, Sköld A, Uchtenhagen H, Vabret N, Ziglio S, Scarlatti G, Shattock R, Wahren B, Gotch F.Rational Design of HIV Vaccine and Microbicides: Report of the EUROPRISE Network Annual Conference 2010. J Translational Medicine 2011, 9:40.
2. M. Cavarelli and G. Scarlatti. HIV-1 co-receptor usage:influence on mother-to-child transmission and pediatric infection. J Translational Medicine 2011 Volume 9 Supplement 1. doi:10.1186/1479-5876-9-S1-S10.
3. A. McMichael and F. McCutchan on behalf of a Working Group convened by the Global HIV Vaccine Enterprise:Host Genetics and Viral Diversity: Report from a Global HIV Vaccine Enterprise Working Group. Nature Precedings doi:10.1038/npre.2010.4797.2.
4. B.Wahren, P. Biswas, M. Borggren, A. Coleman, K. da Costa, W. De Haes, T. Dieltjens, S. Dispinseri, K. Grupping, J. Seifried, P. Selhorst, A. Skold, H. Uchtenhagen, M. J. van Gils, C. Weber, R. Shattock and G. Scarlatti. Rational Design of HIV Vaccine and Microbicides: Report of the EUROPRISE Annual Conference. J Transl Med 2010 26;8:72.
6. A.L. Ross, A. Brave, G. Scarlatti, A. Manrique and L. Buonaguro. Progress towards development of an HIV Vaccine: a report of the AIDS Vaccine 2009 Conference. The Lancet infectious Disease 2010; 10(5): 305-316.
7. Polonis VR, Schuitemaker H, Bunnik EM, Brown BK, Scarlatti G. Impact of host cells on neutralization of HIV-1 in vitro. Curr Opin HIV AIDS. 2009;4(5):400-7.
Project Title:
Project Title:
Mucosal B cell immunity characterization and triggering in HIV-1 infection
The development of a safe and effective HIV-1 vaccine is a global health priority and the elicitation of broadly neutralising antibodies remains the most challenging goal in vaccine development. During HIV-1 infection B cells of the peripheral blood undergo several defects including polyclonal hypergammaglobulinemia, and poor response to specific and vaccination-recall antigens. Little is known on the relevant early B cell subversions occurring at mucosal sites, which are the first portal of HIV-1 entry.
The overall aim of this proposal is to define phenotypic features and functions of relevant B cell populations at mucosal intestinal sites, and thus pursue the second goal: to produce efficient neutralizing monoclonal antibodies (mab) able to limit HIV-1 invasion from the early moments of the infection.
Blood and mucosal intestinal tissue will be obtained from HIV-1 infected individuals (collaboration with the Department of Infectious Diseases) at different stages of diseases and from healthy controls (Dept. Gastroenterology). B cell phenotype will be analyzed with flowcytometry or immunohistochemistry as to define the subpopulations, such as immature/transitional, naïve, memory, resting or activated memory, tissue-like memory, and plasma cells, involved in the mucosal immune response. To produce mabs, relevant B cells will be sorted to obtain single cells. The heavy and light chain of the immunoglobulins will be amplified through Polymerase Chain Reaction. Thereafter the neutralizing activity, epitope specificity and affinity of such antibodies will be analyzed.
This proposal wants to shed light on the mucosal B cell immunity during HIV-1 infection. The knowledge on the population of B cells involved in the early control of the infection and the relevant antibodies produced will be a basis of the future objective of developing a new-concept vaccine able to block the entrance and the subsequent spreading of the virus from the very early phases of exposition.
The overall aim of this proposal is to define phenotypic features and functions of relevant B cell populations at mucosal intestinal sites, and thus pursue the second goal: to produce efficient neutralizing monoclonal antibodies (mab) able to limit HIV-1 invasion from the early moments of the infection.
Blood and mucosal intestinal tissue will be obtained from HIV-1 infected individuals (collaboration with the Department of Infectious Diseases) at different stages of diseases and from healthy controls (Dept. Gastroenterology). B cell phenotype will be analyzed with flowcytometry or immunohistochemistry as to define the subpopulations, such as immature/transitional, naïve, memory, resting or activated memory, tissue-like memory, and plasma cells, involved in the mucosal immune response. To produce mabs, relevant B cells will be sorted to obtain single cells. The heavy and light chain of the immunoglobulins will be amplified through Polymerase Chain Reaction. Thereafter the neutralizing activity, epitope specificity and affinity of such antibodies will be analyzed.
This proposal wants to shed light on the mucosal B cell immunity during HIV-1 infection. The knowledge on the population of B cells involved in the early control of the infection and the relevant antibodies produced will be a basis of the future objective of developing a new-concept vaccine able to block the entrance and the subsequent spreading of the virus from the very early phases of exposition.
Project Title:
Role of dendritic cells and Treg interplay in HIV-1 pathogenesis in the mucosa
HIV-1 transmission occurs mainly via mucosal routes, and is at gut level characterized by an irreversible depletion CD4+ T-cells. Mucosal immune responses to the infection are insufficient to prevent further spreading, however the underlying mechanism remains still elusive.
The aim of the project is to shed light on HIV-1 pathogenesis at mucosal surfaces, Our hypothesis is that �mucosal� DCs, pulsed with HIV-1, do not fully or appropriately mature and thus, induce expansion of T regulatory cells with a specific HIV immune-suppressive function.
Both an in vitro human culture system that mimics the spatial distribution of epithelial and immune cells (established in our laboratory), and ex vivo intestinal tissue samples obtained from HIV-1 infected subjects and healthy donors (from Department of Infectious Diseases and Gastroenterology at HSR) will be used to test our hypothesis. The specific approaches will be: 1. Dissect ex vivo DC and T cell subset profile in the intestinal mucosa of HIV infected patients compared to healthy controls. Phenotype and frequency of CD11c+CD103+ lamina propria DCs and of CD4+CD25+ Treg cells in both mucosal tissues and pheripheral blood will be analyzed by cytofluorimetry and microscopy. 2. Unravel in vitro the HIV-1 induced gut DC-T cell networking. The capacity of DCs (both monocyte-derived and gut purified) to sustain HIV-1 infection and to support viral transfer to CD4+ T cells or Treg cells will be evaluated. 3. Assess if Treg cells specifically suppress anti-HIV-1 specific T cell responses. Treg cells isolated from intestinal tissues or in vitro-induced by DCs, will be stimulated with specific HIV-antigens and co-cultured with autologous T cells. Their response evaluated through evaluation of cytokine/chemokine secretions.
The study will provide relevant information on the mechanisms of mucosal immune dysfunction characteristic of HIV-1 infection, and will permit to identify new relevant targets for the development of future vaccines.
The aim of the project is to shed light on HIV-1 pathogenesis at mucosal surfaces, Our hypothesis is that �mucosal� DCs, pulsed with HIV-1, do not fully or appropriately mature and thus, induce expansion of T regulatory cells with a specific HIV immune-suppressive function.
Both an in vitro human culture system that mimics the spatial distribution of epithelial and immune cells (established in our laboratory), and ex vivo intestinal tissue samples obtained from HIV-1 infected subjects and healthy donors (from Department of Infectious Diseases and Gastroenterology at HSR) will be used to test our hypothesis. The specific approaches will be: 1. Dissect ex vivo DC and T cell subset profile in the intestinal mucosa of HIV infected patients compared to healthy controls. Phenotype and frequency of CD11c+CD103+ lamina propria DCs and of CD4+CD25+ Treg cells in both mucosal tissues and pheripheral blood will be analyzed by cytofluorimetry and microscopy. 2. Unravel in vitro the HIV-1 induced gut DC-T cell networking. The capacity of DCs (both monocyte-derived and gut purified) to sustain HIV-1 infection and to support viral transfer to CD4+ T cells or Treg cells will be evaluated. 3. Assess if Treg cells specifically suppress anti-HIV-1 specific T cell responses. Treg cells isolated from intestinal tissues or in vitro-induced by DCs, will be stimulated with specific HIV-antigens and co-cultured with autologous T cells. Their response evaluated through evaluation of cytokine/chemokine secretions.
The study will provide relevant information on the mechanisms of mucosal immune dysfunction characteristic of HIV-1 infection, and will permit to identify new relevant targets for the development of future vaccines.