Genetic and Immunological Studies of European and African HIV-1+
Long Term Non-Progressors
Keywords: HIV-1, LTNP, Genetics, post-genomic, SNP, NK, gamma-delta, T cell, cohort,
database
Summary:
A minority (<5%) of hiv-1 infected individuals maintains exceptionally
prolonged survival in the absence of clinical symptoms and without
antiretroviral therapy; these individuals have been defined here as long term
non-progressors (ltnp).
Several cohorts of LTNP have been identified in Europe and elsewhere, and
national networks have been formed in France and Italy to better study their
particular features. GISHEAL is the first collaborative European consortium
aimed at investigating the precise nature of the LTNP state, with particular
regard to the host genetic background and gene expression profiling, and to
the adaptive and innate immunological responses to the infection. After
identification of LTNP by all participants, the GISHEAL common database will
be prepared representing the merger of two national (French, Italian)
databases together with individual data collected from the UK and Uganda.
A genome-wide approach based on screening of 500,000 single-nucleotide
polymorphisms (SNP) followed by validation steps,
will lead to the potential discovery of novel
genetic polymorphisms linked to the LTNP
condition, in addition to those already
described.
Their effect in terms of gene
expression will be studied in
different populations of peripheral
blood leukocytes (CD4, CD8,
monocytes, NK and γδ T cells)
using a microfluidic card approach
based on multi-parametric real-time
PCR (TaqMan) in selected LTNP and
chronic progressors (CP) as controls.
The adaptive CD4 and CD8 T
lymphocyte immune responses of LTNP to
HIV-1 will be studied, in comparison to those
of viraemic CP. In parallel, the NK cell and γδ T
cell responses of LTNP and CP will be investigated. The functional
consequences of the potentially novel genetic correlates of LTNP will be also
investigated in these immune cells. A multivariate analysis will allow definition
of the best correlates of non-progression.
Background:
Although some LTNP show later evidence of disease evolution (usually, a drop
of CD4+ T-cell numbers <500 cells/μl blood) and/or have started an
antiretroviral regimen, therefore losing their ltnp status, a substantial fraction
of them have remained ltnp, providing unique examples of natural control of
hiv-1 infection (in some cases exceeding 20 years of infection!). both the
genetic and gene expression profile of the host along with his/her innate and
adaptive immune responses likely contribute significantly to the establishment
and maintenance of the ltnp condition. a central limitation of studies focusing
on ltnp consists of their paucity in individual cohorts. a second limitation is
the heterogeneity in the evaluation of inclusion and follow-up criteria as well
as technical/technological differences among different investigators and
centres.
Aim:
The cohorts participating to GISHEAL have been established in 1994-1996 by
including individuals who already fitted the original definition of LTNP. Central
aim of this project is the creation of the first database encompassing European
and African LTNP Cohorts pooling the information already existing at national
(France, Italy) and individual Centres in UK and Uganda. This will be the basis
for an unprecedented retrospective analysis of correlates of non-progression
in the absence of antiretroviral therapy. Given the existence of biorepositories
in most of the participating institutions, it will be possible to analyse hostrelated
correlates of non-progression regarding the innate and adaptive
immune responses and the host genetic and post-genomic backgrounds.
Expected results:
One of the first results of GISHEAL will be the redefinition of the main
immunologic and virological parameters correlated to the LTNP condition by
the retrospective analysis of the pooled cohorts of the participating members.
In addition, the broad genomic and post-genomic approaches will allow the
validation and, hopefully, the discovery of novel genetic and epigenetic
determinants of nonprogression in HIV-1 disease, while the analysis of the
immune response will provide relevant information on the profiles of classical
adaptive cell-mediated and innate NK cell and γδ T cell-mediated immune
responses of LTNP.
Potential applications:
Identification of genetic, post-genomic and immunological correlates of the
LTNP condition will be of great relevance by providing "golden standards"
for assessing ongoing vaccine trials as well as for the rationale planning of
novel preventive strategies. In addition, they will serve as potential parameters
of immunologic reconstitution in therapeutic trials based on both antiretroviral
agents and immune-based therapies.
Partners:
| Nº |
Principal
Scientific
Participants |
Official Address |
Other Information |
| 2 | Brigitte Autran, M.D. |
Universite Pierre et Marie Curie, Paris-6
Laboratoire d'Immunologie Cellulaire et
Tissulaire, Hpital Piti-Salptrire
83 Bd de l'Hpital, 75013, Paris France
| Tel: 33-1-4217-7481
Fax: 33-1-4217-7490
E-mail: brigitte.autran@psl.aphp.fr |
| 3 | Claudio Casoli |
Department of Clinical
Medicine, Nephrology, and Health
Sciences, University of Parma
via Gramsci 14, 43100 Parma, Italy.
| Tel/Fax: 39-0521-033-261
E-mail: claudio.casoli@unipr.it
Website: www.unipr.it |
| 4 | Dominique Costagliola
Directeur de l'U720 |
INSERM
et Universite Pierre et Marie Curie
Epidemiologie clinique et therapeutique
de l'infection a VIH
56 Bd. V. Auriol, BP 335, 75625, Paris
Cedex 13, France
| Tel: 33-1-4216-4282
Fax: 33-1-4216-4261
E-mail: dcostagliola@ccde.chups.jussieu.fr
Website: www.ccde.fr |
| 5 | Massimo Galli |
Department of Clinical Sciences,
State University of Milano, Az. Osp. Polo
Universitario Luigi Sacco
Via G.B. Grassi n. 74
20157 Milano, Italy
| Tel: 39-02-5031.9763
Fax: 39-02-5031.9758
E-mail: massimo.galli@unimi.it |
| 6 | Frances Gotch |
Department of Immunology,
Imperial College of Science Technology
& Medicine at Chelsea and Westminister
Hospital, 369 Fulham Road London
SW10 9NH, UK
| Tel: 44-(0)-20874-68257
Fax: 44-(0)-20874-65997
E-mail: f.gotch@imperial.ac.uk
Website: www3.imperial.ac.uk/ |
| 7 | Pontiano Kaleebu |
MRC/UVRI
Uganda Research Unit on AIDS c/o Virus
Research Institute
P.O. Box 49, Entebbe Uganda
| Tel: 256-041-320-042
Fax: 256-041-321-137
E-mail: mrc@mrcuganda.org |
| 8 | Fabrizio Poccia |
Immunopatology Laboratory,
Padiglione Del Vecchio I.N.M.I. National
Institute for Infectious Diseases Lazzaro
Spallanzani
Via Portuense 292, 00149 Roma
Italy
| Tel/Fax: 39-06-5517-0904
E-mail: poccia@inmi.it |
| 9 | Ioannis Theodorou M.D. Ph.D. |
Laboratoire Central d'Immunologie
Cellulaire et Tissulaire. Hpital Piti
Salpetrire et INSERM UR543 Btiment
CERVI. 83 Bd de l'Hpital 75013, Paris
France
| Tel: 33-1-4217-7511
Fax: 33-1-4217-7490
E-mail:
ioannis.theodorou@psl.ap-hop-paris.fr |