organisation - the Instituto Gulbenkian de Ciência

INFECTION
AND IMMUNITY
Michael Parkhouse Principal Investigator
PhD in Biochemistry, University of London
Head Immunology, Institute Animal Health, Pirbright, UK
Director, Centro Nacional de Biotechnologia, Madrid, Spain
Special Appointment-equivalent to University Professor, National Institute for Medical Research, Mill Hill, London
Principal Investigator at the IGC since 2000
The theme of the group is the reciprocal adaptation between an infectious
organism and its host. The necessity to recognise and destroy invading pathogens
has played a crucial role in the evolution of the immune system of both
vertebrates and invertebrates. At the same time, pathogens, in particular viruses,
have evolved strategies to manipulate the immune system. An efficient
immune system must select the immune effector mechanism most appropriate
to the biology of the pathogen. Thus, the study of how pathogens control immune
responses will offer novel approaches for the manipulation of the immune
responses in health and disease, with novel vaccines and strategies to
downregulate the immune system (e.g. inflammation) being the most obvious
possibilities. Therefore, we are identifying and characterising virus host evasion
genes directed towards subversion of cell biology and innate immunity. The two
viruses that we have selected are Herpesvirus and the African Swine Fever Virus.
EVALUATING AND CONTROLLING THE RISK OF AFRICAN SWINE FEVER (ASF)
IN THE EU
The aim is to provide new tools and strategies for the control of ASF in Africa and
reduce the risk of importation and/or spread of the disease in EU member states.
GROUP MEMBERS
Rute Nascimento (Post-doc, started in July )
Sílvia Correia (Post-doc)
Helena Costa (PhD student)
Sónia Ventura (PhD student)
Emanuel Costa (Research Technician)
COLLABORATORS
Sun Huaichang (College of Veterinary Medicine, Yangzhou University, China)
Alexandre Leitão (Faculdade de Medicina Veterinária, Universidade Técnica
de Lisboa, Portugal)
John Sinclair (University of Cambridge, UK)
Steve Goodbourn (St. George's Hospital, University of London, UK)
FUNDING
Framework Programme 7 (FP7), European Commission
Fundação para a Ciência e a Tecnologia (FCT), Portugal
We produced B602L, p54, A104R and K205R recombinant proteins which have
been used as antigens to field test ASFV isolates in new recombinant ELISAs by
Dr Carmina Gallardo, CISA-INIA. As the K205R protein revealed high IgM titres,
it has been produced and sent to Dr Carmen Vela, INGENASA, to develop a new
commercial kit able to detect recently ASFV infected animals. An additional ASFV
Interferon evasion gene has been identified using luciferase reporter assays.
INHIBITION OF THE RESPONSE OF THE AFRICAN SWINE FEVER VIRUS AGAINST
HOST INTERFERON
Our objective is to determine the mechanisms and consequences of three nonhomologous
host evasion genes (I329L, K205R and A276R) of the economically
important, frequently fatal African Swine Fever Virus (ASFV). All three genes
inhibit a major component of innate immunity, the Interferon (IFN) response,
and may have practical application through the development of novel pharmaceuticals
that manipulate IFN responses and through the construction of an
attenuated gene deletion ASFV vaccine.
We identified the I329L gene as an inhibitor of TLR3 signalling pathway through
targeting of TRIF (Ventura et al. 2012, in prep). The K205R gene was identified
as an interacting partner of STAT2, therefore inhibits the host antiviral response
by inhibiting the expression of interferon stimulating genes (ISGs) (Correia et al
2012, in prep). Definition of their cellular targets and impact on cellular processes
is a necessary step prior to the construction of a deletion mutant virus vaccine.
MECHANISM AND CONSEQUENCES OF AN IL-8 INDUCING HERPESVIRUS GENE
The project builds on our own observations and experience with UL76 gene
from Human Cytomegalovirus (HCMV), a novel virus host evasion gene previously
lacking a function and, with the exception of the herpesviruses, still without
any homologue in the database. The main objective of this project is to define
the mechanisms employed by UL76 to induce IL-8 expression and G2/M cell
cycle arrest. Understanding this virus strategy for manipulating cell division and
stimulating IL-8 expression may be exploitable for the rational control of these
important infections in humans, for example, the construction of attenuated
herpes virus vaccines, and the development of possible novel approaches for
the manipulation of host cell biology in health and disease.
We demonstrated that UL76 induces IL-8 expression through NF-kB activation
using deletion mutants of IL-8 promoter luciferase reporter. The activation of
NF-kB by UL76 is dependent of IKK-beta and the degradation of IKB-alpha proteins.
Moreover, expression of UL76 results in p65 translocation to the nucleus
and in increased binding of p65 to the IL-8 promoter region as shown by chromatin
immunoprecipitation.
IGC ANNUAL REPORT ‘11
RESEARCH GROUPS
54