Induction and Clearance of Latent HIV Infection:

Transcription

1 214 Towards an HIV Cure symposium Melbourne Induction and Clearance of Latent HIV Infection: an Ex-Vivo Assessment of Immune Effectors using Cells from ART-treated Patients DM Margolis 1, C Garrido 1, JM Sung 1, S Lam 2, R Bateson 1, B Allard 1, N Dahl 1, CR Cruz 2, P Castillo-Caro 3, MT Ngo 3, J Kuruc 1, A Crooks 1, CM Rooney 3, CM Bollard 2, and NM Archin 1 1 University of North Carolina Chapel Hill, NC; 2 Children s National Medical Center, Washington, DC; 3 Baylor College of Medicine, Houston, Texas

2 Model systems to assess clearance Primary cell systems Cytotoxic T cells NK cells o ADCC antibodies o Immunotoxins o Selective apoptosis inducers

3 Why Ex-vivo Expanded CTLs Bypasses impaired immune response Precisely controlled quantity & timing of administration CTLs can persist Safe and effective for treatment of viral infections in oncology patients AM Leen, et al. Nat Med. 26 Bollard, et al. Blood. 27

4 Ex vivo Expansion of HIV-specific T cells T cell ART to prevent In vitro spread ++ HIV-CTLs HXTCs freeze PBMC IL-7 IL-15 IL-2 IL-12 IL-15 Immature DC Cath Bollard, DC Children s Clio Rooney, Baylor and PACT Mature DC + gag/ pol/ nef PHAblast CD32 + K562 CD8/86 4-1BBL

5 HXTCs are a Mixture of Phenotypes % CD8+ T cells 19% CD4+ T cells 8% EM T cells 13% CM T cells 8 7 %Lymphocytes IFN Release to Cognate Peptides

6 HXTCs Inhibit Productively Infected Cells CD8 deplete patient PBMCs Activate 2-3 days wash Superinfect w/ virus via spinoculation Plate in triplicate HIV- CTLs + autologous unexpanded CD8 or expanded HIV-CTLs (or no effector control) Co-culture x 7 days Media change q3-4 days Supernatant harvested for p24 ELISA Yang, et al. JID 212 Freel, et al. J Virol. 212

7 HXTCs Inhibit Autologous Reservoir Virus HIV p24 (% of no effector at day 7) Patient Patient 492 No effectors 1:1 1:1 E:T No effectors 1:1 E:T Patient No effectors 1:1 1:1 E:T Patient No effectors 1:1 E:T No Effectors CD8 HXTC

8 Ex-Vivo Latency Clearance Assay: A modified quantitative viral outgrowth Assay CD8 negative selection CTL Expansion PBMCs Resting CD4 Negative selection CD8, CD14, CD16, CD19, CD56, glycophorin A CD8 or HXTCs or No Effectors Cx with ARVs 24H wash Induction PHA/IL2 or VOR wash Add CTLs Co Cx 24H Add Allo Feeders CoCx x2 Media changes q3-4 days Measure p24 at Day 15 Plate:.5-1x1 6 /well, 12 wells group

9 HXTCs Clear Infected Cells Emerging from Latency PHA Stimulation VOR Induction 8 Et 1:1 12 Et 1: #wells positive (out of 12 total) % viral recovery No Effectors CD8 HXTC p <.3 Wilcoxon signed rank p <.2 t test

10 VOR does not Impair CD8 Antiviral Activity at Physiogically Relevant Exposures HIV p24 (ng/ml) B Viral inhibition assay at E:T ratio 1:1 No CD8 Control No VOR 335nM 5nM 1nM Patient 532 Control hours

11 Why NKs to target residual HIV Crucial innate immune effectors against viral infections Do not recognize specific antigens nor require prior antigen sensitization Function is balanced by inhibitory and activating receptors Kill cells by release of granzymes and perforins, which causes apoptosis NK cells may help control HIV-1 infection Memory NK cells may also provide a more effective antiviral response NK function may be augmented by clinically applicable cytokines

12 VIRAL INHIBITION ASSAY PBMCs Negative isolation NK cells Unstimulated NKs IL-2 /IL-15 stimulated NKs No effectors Negative isolation CD4 + T cells PHA 24h Superinfection (autologous reservoir virus) HIV-CD4 + cells +/- effectors 7 days E:T ratios HIV-p24

13 VIRAL INHIBITION ASSAY % HIV replication Day 7 autologous virus CD4+ 1:1 1:1 1:1 1:1 1:1 1:1 1:1 1:1 1:1 Targets NK resting cells 1 U/mL 25 ng/ml IL2-stimulated NK cells IL15-stimulated NK cells only TARGETS ALONE NK NK + IL2 NK + IL-15 : p <.1

14 LATENCY CLEARANCE ASSAY PBMCs Negative isolation NK cells Unstimulated NKs IL-2 stimulated NKs No effectors Negative isolation Resting CD4+T cells ARV 24h Stimulation 24h CD4+T cells +/- effectors Compare number of positive wells with/without effectors 24 h Add feeders Measure number of positive wells for p24 at day 15

15 LATENCY CLEARANCE ASSAY PHA reactivation VOR reactivation Positive trends but more assays needed

16 IMPACT OF VOR ON NK FUNCTION - NKs were treated with or without 335 nm VOR overnight - For degranulation cells 4 hours in the presence of K562 cell targets Viral inhbition assays NK resting NK + SAHA VO (335 nm) R Targets alone 1:1 1:1 1: %CD56+CD17a NK resting NK+SAHA Degranulation VOR did not impair NK cytotoxicity or antiviral activity

17 Summary Polyclonal HXTCs with activity against multiple peptides can be generated in clinically relevant numbers HXTCs and cytokine-treated NK cells show enhanced antiviral activity Using both lab strain JR-CSF virus and autologous reservoir virus NK cells and HXTCs reduce viral recovery from resting CD4 cells reactivated with PHA/IL-2, demonstrating a potential to clear latent HIV infection ex-vivo Preliminary results also show reduction in viral recovery from resting CD4 cells reactivated with VOR, and no adverse effect on function at relevant VOR exposures

18 Juila Sung MD Carolina Garrido Pavon, PhD Natalia Soriano, PhD Nancie Archin, PhD Noelle Dahl Rosalie Bateson Brigette Allard Joann Kuruc, MSN RN Amanda Crooks Cynthia Gay, MD, MPH Children s National Medical Center Catherine Bollard, MD Sharon Lam Special thanks to the HIV+ volunteers