Eradication of HIVBonaventura ClotetHospital Universitàri Germans Trias i PujolBadalona. Barcelona. Catalonia
HAART blocks viral replication but fails eradicating the HIV-1 infection once started
Vira
l Loa
d
Time after infectionStrain JID 2005
¿Es posible erradicar la infección?
Transient Increase in Episomal Viral cDNA after Intensification with Raltegravir
Buzon, Massanella et al. Nat Med 2010Llibre, Buzon, Massanella et al. Antiv Ther 2011
1-RAL will decrease the number of cells activelyproducing viruses 2-Homeostatic proliferation
Very Early Initiation of ART May Limit the HIV ReservoirDecay of integrated HIV DNA during ART by Fiebig
The frequency of PBMCs harbouring integrated HIV DNA decreases rapidly upon ART initiation in FII to FV individuals, whereas no decay is noted in subjects who started ART during chronic infection.Fiebig I remain below limit of detection.
Geometric mean with 95% CI
ART initiation
CD8-T cells are very important and have
implications for cure strategies and vaccine development
Bruce Walker. CROI 2016. Boston (USA)
How do HIV-specific CD8+ T cellslimit virus production?
Infected cell
More virus made, worse a person doesGoal: limit virus productionPreferentially infects CD4 cells, monocytes, macrophages
Infected cell
Viralproteins
HLA Class I
Infected cell
Infected cell
ViralPeptides
(epitopes)HLAClass Ialleles
CD8
Infected cell
HIV-specific CD8+ T cell(Cytotoxic T lymphocyte, CTL)
CD8
Infected cell
T cellReceptor
CD8receptor
CD8
CD8Antiviralcytokines
and chemokines
1. Require only one to a few viral peptide-HLA complexes for recognition
2. Can kill infected cells before progeny virions produced
Lytic granules
Question
• What are the characteristics of HIV-specific CD8+ T cells that contribute to immune control?
Infected cell
“Protective” and “Risk” HLA Alleles
HLAB*3503
HLAB*5701
Kaslow Nat Med 1996Gao NEJM 2001Migueles PNAS 2000Kiepiela Nature 2004Felay Science 2007Dalmasso Plos One 2008Limou JID 2009Pereyra Science 2010Pelak JID 2010Herbeck JID 2010
Infected cell
Viral Peptides Targeted
Viralpeptides
Klein JEM 1995Edwards JV 2002Novitsky JV 2003Masemola JV 2004Zuniga JV 2006Geldmacher JV 2007Kiepiela Nature 2007Pereyra JV 2014Migueles Ebio 2015
CD8
Day Nature 2006Trautmann Nat Med 2006Petrovas JEM 2006
HIV-specific CD8+ T cell exhaustion
PD-1
Continous exposure to viral antigenspromotes PD-1 expression
CD8Viral mutation/immune escape
Phillips Nature 1991Goulder Nat Med 1997Borrow Nat Med 1997Goulder Nature 2001Brockman JV 2007Kawashima Nature 2009Goonetilike JEM 2009Liu JCI 2013Carlson Science 2014Redebe AIDS 2015Roberts Nat Gen 2015
Immune Escape
Conclusions I1. HIV-specific CD8+ T cells can kill virus infected
cells before progeny virions are produced2. HLA and the viral peptides presented
influence viral load3. HIV-specific CD8+ T cells differ in antiviral
efficacy4. Viral mutations in CD8+ T cell epitopes lead to
immune escape5. Persistent viremia leads to dysfunction of
these cells
Latency reversing
agent (LRA)
Shan Immunity 2012Sung JID 2015
Latentlyinfected cell
CD8
Latency reversing
agent (LRA)
Shan Immunity 2012Sung JID 2015
Latentlyinfected cell
CD8
Latency reversing
agent (LRA)
Shan Immunity 2012Sung JID 2015
CD137: Activation marker
CD8+ T cells as biosensors to define effective
latency reversing agents in vitro
RB Jones, unpublished
Infected cell
LRA
CD8
Escape mutation
Deng et al, Nature, 2015
Target non-escaped epitopes
Deng et al, Nature, 2015
Infected cell
CD8
Escape mutation
Subdominant epitope
Subdominant CD8+ T cell response
Deng et al, Nature, 2015Hancock PLoS Path 2015Sung JID 2015
Conclusions III
• Early treatment of hyperacute HIV infection enhances therapeutic vaccine responses
• HIV cure strategies will likely require CD8+ T cell-mediated elimination of infected cells, through targeting of subdominant epitopes
• HIV-specific CD8+ T cells can contribute to HIV vaccine efficacy, in conjunction with other immune responses
Post-CROI 2015
Kick and Kill Strategy to EliminateReservoirs of Latent HIV
Modified ImmunoglobulinsHet IL15
IMMUNOTHERAPY
Mascola JR. CROI 2016, Boston MA. #15.
ABSTRACT 32LB
Passive administration of bnAbs (VRC01) prevents HIV-1 transmission in humanized mice, macaques.Transiently reduces plasma viral loads by ~1-3 logs in HIV infected humans
Results: Viral rebound
A5340
• Majority of participants rebounded by week 5• 2 participants with delayed rebound at 8, 11 weeks
• Time to rebound not associated with VRC01 level, age, nadir or entry CD4 ct, time on ARTBar KJ. CROI 2016, Boston, MA. #32LB.
Mascola JR. CROI 2016, Boston MA. #15.
Combined Antibodies:Improved Potency and
Breadth
Kong, Montefiori Korber et al. J. Virol (2015)
2 mAbs > 98% coverage
Highly potent multifunctional antibody-based molecules against Human Immunodeficiency Virus.
Julià Blanco, Jorge Carrillo, Bonaventura Clotet
Recombinant antibodies with enhanced antiviral activity: The eCD4-Ig molecule
Highly potent multifunctional antibody-based molecules against HIV
IC50 (ng/ml)NL43 BAL AC10 Description
MOLECULE-0 10,820 27,390 >100 1st GenerationMOLECULE-1 0,108 0,050 >100 REFERENCE (Farzan’s)MOLECULE-5 0,037 0,007 0,375MOLECULE-7 0,029 0,004 0,189MOLECULE-8 0,035 0,028 1,327
MOLECULE-10 0,793 2,924 >100MOLECULE-11 0,110 0,026 1,454
RATIO MOLECULE-7/ MOLECULE-1
x5 x12 >100
1) Antiviral activity
Recombinant antibodies: IrsiCaixa moleculesHighly potent multifunctional antibody-based molecules against HIV
AlbaJuna molecules
2) Antibody Dependent Cellular Cytotoxicity (ADCC)
Highly potent multifunctional antibody-based molecules against HIV
Recombinant antibodies: IrsiCaixa molecules
THERAPEUTIC VACCINE
Main obstacles to HIV vaccine and eradication research
Huge viral diversity around the world—rapid evolution
+
HIV destroys host’s immune system
+
HIV establishes a long-life reservoir very early in infection
in resting memory cells not accessible to drug/immune
system if not reactivated
Vaccinecandidate
Vectors(vehicles)
Immunogens (active component)
Need to be safeNot induce anti-vector immunity
Feasible to produce
Able to induce antibodies& cellular responses effective to contain with viral diversity
To design a focused immunogen sequence displaying the major viral targets for protective/beneficial HIV-1 specific T cell responses able to break immunodominance to
non-beneficial targets ensuring a broad HLA class I and class II coverage.
Immunogenicity data from >1,000 infected individuals screens for T cell responses to the entire HIV proteome yielded26 regions identified as “beneficial” (PR>1) in HIV-1 Gag, Pol, Vif and Nef proteins that were:
i) preferentially targeted by individuals with low viral loads, ii) turned out to be more conserved and iii) elicited responses of higher functional avidity and broader cross-reactivity
Mothe B et al, PLos One 2012Mothe B et al, JTM 2012
HIVACAT T-cell Immunogen design (HTI)3
0
2
4
6
8
2x pDNA 2x pDNA1 MVA
3x pDNA 3x pDNA1 MVA
# o
f IF
Ng
resp
on
ses
Ga
g-p
17
Ga
g-p
24
Ga
g-p
15
Po
l-P
rot
Po
l-R
T
Po
l-In
t
Vif
Ne
f0
250
500
750
1000
1250
IFN
g S
FC
/10
6sp
len
ocyte
s
MVApDNA: 100µg IM / dose MVA: 10^6pfu IM / dose
GagPolVifNef
3x pDNA + 1 MVA3x pDNA
CD4CD8
G ag P o l V if N ef0.00
0.25
0.50
Mean and SD is shown
% IF
Nγ+
CD
3+ s
plen
ocyt
es
6 out of 6 mice
Ga
g-p
17
Ga
g-p
24
Ga
g-p
15
Po
l-P
rot
Po
l-R
T
Po
l-In
t
Vif
Ne
f0
250
500
750
1000
1250
IFN
g S
FC
/10
6sp
len
ocyte
s
MVA boost increases responses broadly after 3 pDNA vaccinations
0
1000
2000
3000
4000
5000
# of
HIV
supr
otei
ns (n
=8)
with
IFN
g re
spon
seHIVACAT T-cell Immunogen design (HTI)
3
Two DNA immunizations only elicited responses in 3/5 animals.
Interestingly, MVA-HTI vaccine was able to boost responses (both in breadth and magnitude,) in the two groups analyzed, with significantly increased magnitudes of responses in the group that obtained 3 doses of pDNA-HTI
(median total IFNg positive responses of 777 vs 2865 SFC/million splenocytes after 3xpDNA and 3xpDNA followed by 1xMVA respectively, p= 0.0087).
MVA-HIVACAT vaccine Elicits CD8 effector memory response (which has been associated with HIV control in Elite Controllers and in the animal model(Picker et al. Nature 2011)
Journal of Translational Medicine. Bea Mothe et al 2015
HIVACAT T-cell Immunogen design (HTI)
Currently the 3 most interesting clinical trials for HIV eradication combining vaccine and HDACs are:
1-REDUC (Vax4x + RMD) chronically infected HIV patients (Danish group)2-RIVER (HIVconsv + SAHA) early treated does not include stop of ARVs (Londres/Oxford)3-BCN02-Romi (HIVconsv + RMD) early treated includes Stop of ARVS (irsicaixa-Hivacat/Barcelona)
ABSTRACT 26LB
VACC-4
• Vacc-4x consist of 4 peptides (20-27aa each one) corresponding to conserved regions on the p24 protein slightly modified to optimize HLA presentation.
• The vaccine is administered with GM-CSF as adjuvant for DCs.
• The vaccine is intended to induce, sustain or recover CD4+ and CD8+ T cell responses to p24, so that the immune cells recognize and remove infected cells presenting the native versions of such p24 peptides
ABSTRACT 26LB
ABSTRACT 26LB
ABSTRACT 26LB
ABSTRACT 26LB
ABSTRACT 26LB
REDUC TRIAL (1)• The latent HIV reservoir was significantly reduced by 40%
Total HIV DNA and qVOA (quantitative viral outgrowth assay). The impact on proviral DNA after RMD could have been mediated by NK or ADCC???
• 8 out of 17 (47%) had detectable VL (but low levels < 100 c/ml) during RMD infusion
• Reactivation of the latent HIV reservoir was confirmed by increases in histone acetylation levels and viral expressions.
• After ARV treatment interruption median time to viral rebound > 50c/ml, 14 days
• The combination of Vacc-4x and RMD was safe and well tolerated
REDUC TRIAL (2)
• The possible explanation for not impacting the viral rebound could be:1-The DNA decay observed was low (0.5 log) in a
group of patients that started therapy at chronic stages with high proviral DNA at BL (1000 c/Milion of CD4s). Despite the decay achieved still quite high viral reservoir was present at the time of ATI. As a reference point in elite or post-treatment controllers viral reservoir is usually much lower (
REDUC TRIAL (3)
• The possible explanation for not impacting the viral rebound could be:2-This vaccine did not induce specific CD8 responses3-In vitro studies has not shown suppressor activity4-Even in the phase II study showing 0,5 lower viral set
point after ATI (Pollard Lancet Infect Dis), there was not delay in the viral rebound
5-Timing of vaccine and RMD and ATI (between last vaccination and ATI-14 weeks) was not the optimal and if any response was achieved, it was light and could have disappeared
REDUC TRIAL (4)• How to overcome the problem:• A better vaccine stimulating significantly and
long-lasting the CD8 could impact the rebound and delay it
• There is a need to achieve lower levels of the viral reservoir before ATI in all vaccine trials (select very early treated patients or use more potent vaccine+LRA or use more shoots of LRA but with lower doses?)
• These suggestions need to be assessed in the upcoming clinical trials
B CELL FOLLICLE SANCTUARY
CD8 can not enter into the B-cell follicle
• Lymphocyte expansion and differentiation
• Enhanced activation and cytotoxicity
• Migration via increase of CXCR5
259LB Increased Effector CD8 Lymphocyte Trafficking to Lymph Nodes Induced by hetIL-15 (heterodimeric IL-15)
259LB Increased Effector CD8 Lymphocyte Trafficking to Lymph Nodes Induced by hetIL-15 Conclusions: We explore the potential of IL-15 as a viral reservoir reducing agent in ART-treated SIV infected macaques. hetIL-15 treatment enhances the number, activation and cytotolytic potential of CD8 cells in LN and germinal centers, a known site of virus persistence. hetIL-15 treatment in combination with pDNA vaccine targeting the “Achilles’ heel” of the virus, i.e., the highly conserved regions (CE), in virus sanctuary areas (germinal centers) is a promising HIV eradication strategy.
COMBINATION OF STRATEGIES TO ACHIEVE THE CURE OF HIV
Infectedcell
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
Vaccine (HTI)
T
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
DC (SIGLEC-1) DeliveredHDAC Inhibitors,TLR-7;
Anti-PD1 boosting?
Vaccine (HTI)
Infectedcell
T
Virus inactivationVirus
Neutralizationby AJ-Mabs
New infections protection
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
IgGsAlbaJunaMabs (AJ-Mabs)
(IgG+CCR5+CD4+FX)
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
Anti-PD1 boosting?
AJ-Mabs
XVaccine (HTI)
NK
Infectedcell
T
Virus inactivationVirus
Neutralizationby AJ-Mabs
New infections protection
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
IgGsAlbaJunaMabs (AJ-Mabs)
(IgG+CCR5+CD4+FX)
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
Anti-PD1 boosting?
AJ-Mabs
AJ-Mabs
XVaccine (HTI)
NK
Infectedcell
T
Virus inactivationVirus
Neutralizationby AJ-Mabs
New infections protection
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
IgGsAlbaJunaMabs (AJ-Mabs)
(IgG+CCR5+CD4+FX)
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
DC (SIGLEC-1) DeliveredHDAC Inhibitors,TLR-7,hetIL-15
Anti-PD1 boosting?
AJ-Mabs
AJ-Mabs
XVaccine (HTI)
NK
Infectedcell
T
Virus inactivationVirus
Neutralizationby AJ-Mabs
New infections protection
Infected celldestruction
HIV-1 infected patient HIV-1 free individual
IgGsAlbaJunaMabs (AJ-Mabs)
(IgG+CCR5+CD4+FX)
Multiple strategies for eradication
Vaccine (HTI)
CTLCTL
DC (SIGLEC-1) DeliveredHDAC Inhibitors,TLR-7hetIL-15
Anti-PD1 boosting?
•Therapeutic Vaccine (HTI)•HDACs inhibitors delivered through Siglec-1
mechanism; TLR7; Heterodimeric IL-15•Anti-PD-1 as CD8 and vaccine boosters?•Recombinant proteins (AlbaMab/JunaMab)•Microbiome
AJ-Mabs
AJ-Mabs
XVaccine (HTI)
THANK YOU VERY MUCH
Special thanks to Bruce Walker and to my colleagues Julià BlancoJavier Martinez-Picado, Bea Mothe& Roger Paredes
Dianummer 1Dianummer 2¿Es posible erradicar la infección?Dianummer 4Transient Increase in Episomal Viral cDNA after Intensification with RaltegravirDianummer 6Very Early Initiation of ART May Limit the HIV Reservoir�Decay of integrated HIV DNA during ART by Fiebig CD8-T cells �are very important and have implications for cure strategies and vaccine development� �Bruce Walker. CROI 2016. Boston (USA)�Dianummer 9Dianummer 10Dianummer 11Dianummer 12Dianummer 13Dianummer 14Dianummer 15Dianummer 16Dianummer 17QuestionDianummer 19Dianummer 20Dianummer 21Dianummer 22Conclusions IDianummer 24Dianummer 25Dianummer 26CD8+ T cells as biosensors to define effective �latency reversing agents in vitroDianummer 28Target non-escaped epitopes�Dianummer 30Conclusions IIIDianummer 32Dianummer 33Dianummer 34Dianummer 35Dianummer 36Results: Viral reboundDianummer 38Dianummer 39Dianummer 40Dianummer 41Dianummer 42Dianummer 43Dianummer 44Dianummer 45Dianummer 46Dianummer 47Dianummer 48Dianummer 49Dianummer 50VACC-4Dianummer 52Dianummer 53Dianummer 54Dianummer 55Dianummer 56REDUC TRIAL (1)REDUC TRIAL (2)REDUC TRIAL (3)REDUC TRIAL (4)Dianummer 61Dianummer 62Dianummer 63Dianummer 64Dianummer 65Dianummer 66Dianummer 67Dianummer 68Dianummer 69Dianummer 70Dianummer 71Dianummer 72Dianummer 73Dianummer 74Dianummer 75
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