IAS 25 Towards an HIV Cure symposium Vancouver Distinct HIV Genetic Populations in Effector Memory T Cells after Prolonged Therapy
Questions about long-lived HIV reservoirs Effective ART Memory CD4+ T cell subsets Effect of very prolonged ART (>5 years) on the genetic composition of HIV-DNA? HIV transcripts Full stimulation Relationship between the genetic composition of HIV-DNA and the level of HIV-RNA transcripts? Active viral transcription
Method Overview UCSF: 6 Participants on very prolonged ART >5 years: 4 initiated ART during chronic infection (PT-4) 2 initiated ART during early infection (PT5-6) Leukapheresis Rectal biopsies VGTI: o CD4+ Naïve T cells (T N ) o CD4+ Stem Cell Memory T cells (T SCM ) o CD4+ Central memory T cells (T CM ) o CD4+ Transitional memory T cells (T TM ) o CD4+ Effector memory T cells (T EM ) CD4+ Homing subsets: CXCR5+CCR6- (X5+) CXCR5-CCR6+ (R6+) CXCR5+CCR6+ (X5+R6+) CXCR5-CCR6- (X5-R6-) CD4+ T cells CD8+ T cells CD- T cells CD4-CD8- T cells TILDA (tat/rev induced limiting dilution assay) WMI: DNA sequencing by Single-Proviral Sequencing Gag-pol (p6-rt) sequences
T EM contains clonal HIV-DNA Overall % clonal HIV-DNA T EM was highly enriched with clonally expanded identical HIV-DNA when compared to other cellular subsets PT PT 2 PT PT 4 Overall of 4-66% clonally expanded HIV-DNA in participants treated during chronic infection
2 Mechanisms of Cellular Proliferation Memory CD4+ T cell Antigen specific response Stable pool of CD4+ memory T cells IL-7 IL-2 Large phylogenetic group containing clonally expanded HIV-DNA Small phylogenetic groups containing clonally expanded HIV-DNA
9 9 Cellular proliferation by by antigen-specific homeostatic response.5.2 67. 7 5. 87 89 6 4 59 78 7 5 74 89 82 56 72 6 5 25 8 79 6 29 4 67 7 46 8 PT PT 55 69 4 66 5 6 26 52 7 58 58 44 59 4 4 7 6 49 62 9 96 5 42 7 62 94 2 8 9 2 4 2 PT2 PT4 79 4 49 6 96 25 4 96 4 65 4 95 74 54 5 84 8 8 4 4 62 74 8 4 69 9 86 75 5
Effector memory contain 82% clonal hypermutated HIV-DNA 62. 8 67 6 29 79 72 % Hypermutants in T EM 6 5 56 4 T EM contained 82% clonal hypermutants 25 8 55 7 46 4
Effector memory contain % clonal wild-type HIV-DNA 9 59 74 8 9 4. 5 4 7 4 44 6 69 5 6 7 % of HIV-DNA in T EM were clonal wild-type 54 66 4 7 2 49 25 95 6 94 9 79 4 96 5
Effector memory contain 5% clonal drug resistant HIV-DNA 82.5 87 5% HIV-DNA in T EM clonal HIV-DNA carrying DRMs
6 5 5 7 25 5 4 44 6 Enrichment of hypermutants in T EM (treatment during early infection) 22 29 2.. 6 4 24 7 66 49 2 46 5 2 59 6 9 5 2 6 Hypermutants 45 62 PT5 % Diversity=.7% 52 46 8 6 PT6 % Diversity= 2.5% 49 65 7 9 2 66 Premature stops
Inducible HIV transcripts in CD4+ memory subsets T CM, T TM and T EM subsets derived from all participants produced multiply spliced HIV transcripts upon full stimulation
Conclusions The distribution of HIV- genetic material among memory subsets varied dramatically across the cohort after prolonged ART. Clonal expansions of HIV-DNA can be driven by random antigen-driven cellular proliferation and/or homeostatic response. T EM are marked by clonal expansions with distinctive HIV-DNA genetic populations which reflects cellular proliferation induced by antigen-specific response. Genetic analysis reveals that proliferative bursts can be attenuated by cellular restriction factors and/or by death of cells expressing replication competent virus. The amount of inducible viral transcripts is lower in T EM from an individual with expanded hypermutant populations.
Acknowledgements Palmer lab WMI: Centre for Virus Research/Karolinska Associate Professor S. Palmer K. Barton J-S Eden B. Hiener S. von Stockenstrӧm A. Winckelmann WMI: Centre for Virus Research Professor T. Cunningham A. Harman N. Nasr M. Kim K. Sandgren Rachel, Kirstie, Ani, Naomi, Daisy, Abdullah, Joey AGRF Bhawana Nain and her team VGTIFL/Montreal N.Chomont R.Fromentin Department of Epidemiology and Biostatics UCSF P. Bacchetti Leidos Biomedical Research Inc. Frederick National Laboratory for Cancer Research W. Shao Immunology Laboratory, Vaccine Research Centre, NIH E. Boritz D. Douek Department of Medicine UCSF F. M. Hecht S. G. Deeks M. Somsouk P. Hunt D. Douek E. Sinclair P. Lewis H. Hatano L. Epling M. Kilian T. Ho A. Tan J. Custer L. Loeb R. Hoh L. Poole We acknowledge with gratitude the participants of this study