2014 “Towards an HIV Cure” symposiumMelbourne
Genetically Characterizing the Role of
Cell Proliferation in Maintaining Persistent HIV during Effective HIV Therapy
Sarah Palmer
Westmead Millennium Institute and University of Sydney
Background
•A diverse repertoire of naive and memory T cells is maintained to defend against new and previously encountered pathogens
•The level of peripheral T cells is closely regulated and is maintained by cellular proliferation and homeostatic proliferation which takes place within the T cell area of the spleen and lymph nodes
•However, T cell proliferation, differentiation and activation have poorly defined effects on the latent HIV reservoir during potent cART
Objectives of the Study
Patient 6Treated during chronic infection> 5 years of therapy
PlasmaPre-Therapy - 2004Pre-Therapy - 2005On-Therapy – Time Point 1On-Therapy – Time Point 2
GALT – Effector Memory
GALT – NaiveGALT – Central / Transitional Memory
On-therapy – First Time Point
Peripheral blood – Central / Transitional MemoryPeripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – All Memory
On-therapy – Second Time Point
Peripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – Central MemoryPeripheral blood – Transitional Memory
GALT – Effector Memory
GALT – NaiveGALT – Central / Transitional Memory
0.005
19 Identical Sequence Expansions2 Identical Sequence Expansions Include Pre-therapy
Identical Sequences Identical sequences during long-term
suppressive therapy>2 genetically identical sequences
Time Point 1 Time Point 2 Time Point 1 Time Point 2Naïve 33% 33% 0% 0%
Memory All 19% N/A N/A N/A
Central/Transitional Memory 18% N/A 27% 0%Central Memory N/A 11% N/A N/A
Transitional Memory N/A 6% N/A N/A
Effector Memory 33% 57% 8% 83%
Cell TypeBlood GALT
Time Point 1: EM vs CTM > 2-fold p = 0.3
Time Point 2: EM vs CM > 11-fold p = 0.001
EM vs TM > 20-fold p < 0.001
33% 57%
Patient 8Treated during chronic infection>8 years of therapy
PlasmaPre-Therapy - 2000Pre-Therapy - 2002
GALT – Effector Memory
GALT – NaiveGALT – Central / Transitional Memory
On-therapy – First Time Point
Peripheral blood – Central / Transitional MemoryPeripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – All Memory
On-therapy – Second Time Point
Peripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – Central MemoryPeripheral blood – Transitional Memory
GALT – Effector Memory
GALT – NaiveGALT – Central / Transitional Memory
Lymph node tissue – Effector Memory
Lymph node tissue – NaiveLymph node tissue – Central MemoryLymph node tissue – Transitional Memory
Identical Sequences
Identical sequences during long-term suppressive therapy
27 Identical Sequence Expansions1 Identical Sequence Expansion Includes Pre-therapy
0.01
Time Point 1: EM vs CTM > 2-fold p = 0.2
Time Point 2: EM vs CM > 20-fold p = 0.0001
EM vs TM 7-fold p = 0.01
Time Point 1 Time Point 2 Time Point 1 Time Point 2 Time Point 1 Time Point 2Naïve 24% 22% N/A N/A N/A 17%
Memory All 38% N/A N/A N/A N/A N/A
Central/Transitional Memory 53% N/A 30% 0% N/A N/A
Central Memory N/A 15% N/A N/A N/A 12%Transitional Memory N/A 35% N/A N/A N/A 26%
Effector Memory 73% 79% 6% 17% N/A 61%
Cell TypeBlood GALT LNT
73% 79% 61%
Time Point 2: EM vs CM > 11-fold p = 0.0003
EM vs TM > 4-fold p = 0.02
61%
Patient 7Treated during chronic infection> 9 years of therapy
PlasmaPre-Therapy - 2002
GALT – Effector Memory
GALT – NaiveGALT – Central / Transitional Memory
On-therapy – First Time Point
Peripheral blood – Central / Transitional MemoryPeripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – All Memory
On-therapy – Second Time Point
Peripheral blood – Effector Memory
Peripheral blood – NaivePeripheral blood – Central MemoryPeripheral blood – Transitional Memory
0.005
Identical Sequences
Identical sequences during long-term suppressive therapy
9 Identical Sequence ExpansionsNO Identical Sequence Expansions Include Pre-therapy
Time Point 1 Time Point 2 Time Point 1 Time Point 2Naïve 33% 0% N/A N/A
Memory All 70% N/A N/A N/A
Central/Transitional Memory 0% N/A 50% N/A
Central Memory N/A 57% N/A N/A
Transitional Memory N/A 12% N/A N/A
Effector Memory 82% 92% 19% N/A
Cell TypeBlood GALT
Time Point 1: EM vs CTM > 30-fold p < 0.0001
Time Point 2: EM vs CM 9-fold p = 0.002
EM vs TM > 86-fold p < 0.0001
82% 92%
0.005
SCOPE2013: Leukapheresis
46
37
100367
78
29
98
0.01
Leuka TCM
Leuka TTM
Leuka TEM
Leuka DN (X5-R6-)
Leuka R6 (X5-R6+)
Leuka X5 (X5+R6-)
Leuka DP (X5+R6+)
On-Therapy
Hypermutants
stop
Viable
Subset Hypermutant (%)
Leuka TCM 50.0 (5/10)
Leuka TTM 11.5 (3/26)
Leuka TEM 100 (24/24)
Leuka DN (X5-R6-) 90.9 (20/22)
Leuka X5-R6+ 90.5 (19/21)
Leuka X5+R6- 0.0
Leuka DP (X5+R6+) 0.0
Treated during chronic infection > 15 years of therapy
97
100
13
40
84
42
97
99
0.01
% APD: 1.4%
Subset % Identical sequences
Leuka TCM 50.0 (2/4)
Leuka TTM 52.2 (12/23)
Leuka DN (X5-R6-) 0.0 (0/2)
Leuka R6 (X5-R6+) 0.0 (0/2)
Leuka X5 (X5+R6-) 75.5 (3/4)
Leuka DP (X5+R6+) 50.0 (3/6)
Cellular Restriction Factors
Legend:
SLFN11: inhibits viral protein synthesis
Tetherin: blocks viral release
APOBEC3: Hypermutation; lethal mutations in viral DNA
MX2: blocks nuclear import of subviral complexes; blocks integration
Conclusions
A large percentage of intracellular sequences, not represented in pre-therapy plasma, are clonal in nature.
These identical sequences are enriched during therapy and in more differentiated cells ie: effector memory.
This suggests that HIV persistence during effective therapy is driven in large part by the proliferation, differentiation and expansion of cell populations with sustained and durable regenerative potential.
Acknowledgements
We acknowledge with gratitude the participation of all the patients in this study
Karolinska Institutet L. OdevallS. von Stockenström
VGTIN. Chomont
SAIC/NCIW. Shao
University of California, San FranciscoF. HechtE. SinclairP. BacchettiP. LewisP. HuntM. SomsoukH. HatanoS. DeeksL. EplingM. Kilian T. HoA. TanJ. CusterL. LoebR. HohL. PooleS. PillaiM. Abdel-MohsenA. Raposo
Westmead Millennium InstituteE. LeeB. HienerK. BartonM. LoganT. Cunningham
VRC/NIAIDD. DouekE. Boritz
Rega Institute, BelgiumN. FariaP. Lemey
Top Related