HIV Antibody Characterization for Reservoir and Eradication Studies. Michael Busch, Sheila Keating, Chris Pilcher, Steve Deeks

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1 HIV Antibody Characterization for Reservoir and Eradication Studies Michael Busch, Sheila Keating, Chris Pilcher, Steve Deeks Blood Systems Research Institute University of California San Francisco, CA

2 OVERVIEW Background and current field of HIV staging and recency/incidence testing Preliminary studies to investigate repurposing of incidence assays for HIV reservoir measurement and cure research Planned studies to advance development and validation of Ab characterization for blood HIV reservoir analyses funded by DARE & BMGF

3 HIV diagnostics and staging during early infection

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7 Challenges to Using Antibody Maturation to Identify Recent Infection Variable immune response among individuals Antibody response related to viral level Variability by HIV-1 subtypes False-recent status (long-term specificity) Elite controllers (low viral levels) ART use (low viral levels) Advanced HIV disease (AIDS)

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9 Mean Durations of Recent Infection and False Recent Rates Number of patients [number of data points] MDRI (days) 95% CI (days) *FRR (%) Lag (1.5 Odn) 400 [1032] BED (0.8 Odn) 400 [1032] LS-Vitros (20 S/C) 400 [1032] Vitros Avidity (AI 60 ) 400 [1032] Bio-Rad GS PLUS O Avidity (AI 40) 400 [1032] *Excluding specimens from identified elite controllers and subjects with treatment exposure

10 Current Issues in Measuring HIV Reservoir No gold standard for measuring HIV reservoir HIV reservoir is much larger in tissue (lymph nodes) than blood How will we measure the success of HIV cure treatments if no gold standard assay exists? Most HIV measures are virologic assays, not cell-based assays Erikkson PLoS Pathogens 2013, Ho Cell 2013, Yukl JID 2010

11 Current Issues in Measuring HIV Reservoir No gold standard for measuring HIV reservoir HIV reservoir is much larger in tissue (lymph nodes) than blood How will we measure the success of HIV cure treatments if no gold standard assay exists? Most HIV measures are virologic assays, not cell-based assays Can the host humoral immune response against HIV proteins provide a surrogate for the systemic HIV reservoir?

12 Using Seroreversion as a Marker of Viral Suppression

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14 Limited Seroconversion Following Early ART Based on Vitros LS and Avidity Assays

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16 Reduction in HIV Ab reactivity in EC and Following ART in CEPHIA Keating et al. CROI 2014

17 The Berlin Patient: HIV Eradication Yukl et al. Plos Pathogens 2013

18 Stem Cell Transplant during HIV-Treatment Changes in HIV Ab levels following allogeneic (CCR5-expressing) HSC transplant in 2 HIV+ pts who had absence of HIV RNA and DNA detection post-transplant (on HAART during and after HSC transplant) LAg Assay Treatment LS-VITROS Assay Timothy Henrich & Daniel Kuritzkes, IAS 2012&IAS 2013 Journal of Infectious Diseases 2013

19 Early and Late ART Treated Cohort ELT: 60 Options patients; 5 serial plasma samples. 30 were treated during acute and 30 during chronic infection.

20 Early and Late Treated ART Cohort ELT: 60 Options patients; 5 serial plasma samples. 30 were treated during acute and 30 during chronic infection.

21 HIV Ab Luminex Assay Kelly Curtis Bio-Plex 200 System (Bio-Rad) Uses polystyrene microspheres bound to an antigen to capture and detect specific antibodies in a sample 100 distinct microsphere sets, allowing for detection of 100 different analytes in one sample Uses extremely small sample volume (1µl/well) Multiple analyte detection in one well Determines total Ab binding (normalizing using a calibrator) or Ab avidity (using a chaotropic agent) Some of the antigens used: p24, p31, p66, gp120, gp160, gp41 Ag + + DEA treatment Microspheres are aligned in single file and passed through 2 lasers 1 st laser excites molecular tags- Data output as mean fluorescent intensity (MFI) 2 nd laser excites microsphere and identifies dye signature (identifies analyte)

22 Normalized Ab Concentrations HIV-Specific IgG: Longitudinal Seroconversion Panels Ab Avidity 527 Specimens 109 Subjects * Curtis KA, Kennedy MS, Charurat M, Nasidi A, Delaney K, Spira TJ, et al. Development and Characterization of a Bead-Based, Multiplex Assay for Estimation of Recent HIV Type 1 Infection. AIDS Res Hum Retroviruses 2011.

23 Luciferase Immunoprecipitation Assay (LIPS) to Detect HIV Antibody Levels Peter Burbelo 1. Luciferase-antigens: gp120, gp41, reverse transcriptase, integrase, protease, matrix, p24 2. Add diluted sample 3. Add IgG beads binds Ag-bound Ab 4. Measure luciferase Burbelo JID 2014

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25 Abs to Env > Pol > Gag Proteins in LIPS Correlate with HIV-1 Reservoir Size? gp120 gp41

26 Can HIV-specific antibody binding patterns be used to characterize HIV infection and cure? Kathryn Stephenson 1. Global HIV peptide microarrays can be used to map HIV-specific antibody binding patterns 2. The antibody binding patterns evolve following stem cell transplantation 3. The antibody binding patterns might be used to stage HIV infection, from acute infection to reservoir reactivation Stephenson et al. J Immunol Methods 2015; 416:105

27 HIV Ab Evolution Post- SCT Ab Specificities Appear Ab Specificities Disappear

28 Using B cells as biomarkers to monitor viral reactivation Galit Alter Gycosylation changes with inflammatory profile Gycosylation changes with HIV disease Is galactose an early sensor of viral replication? Ackerman JCI 2013

29 DARE Eradication Studies: Using Antibodies to Monitor Eradication UCSF Early vs Late Treatment (ELT) and Blip Panels: ELT: ART treated during acute and during chronic infection The Blip group: treated with ART during chronic infection but with frequent VL blips on commercial VL assays Long-term ART suppressed pts: ACTG HIV Reservoir Cohort (A5321) Elite Controller (EC) Panel: Longitudinal samples from ECs from UCSF, US and South African blood donors documented to be ECs. Treat Elite Panel: ECs with therapeutic trial of HAART demonstrating significant reduction in plasma and gut biopsy VL by ultrasensitive methods as well as reduction in immune activation. Cure protocols: Longitudinal series of samples from multiple patients enrolled in: HAART intensification protococls, HIV patients receiving HSCT, Treatments employing shock and kill regimens (Vorinostat, Disulfiram, Panobinostat), other Cure strategies

30 Acknowledgements BSRI Mila Lebedeva Dylan Hampton Philip Norris UCSF Chris Pilcher Steve Deeks Sulggi Lee Rick Hecht Shelly Facente Kara Marson Public Health England Gary Murphy CEPHIA SACEMA Alex Welte Reshma Kassanjee David Matten Centers for Disease Control Kelly Curtis Ragon Institute of MGH, MIT and Harvard Galit Alter Center for Virology and Vaccine Research Beth Israel Deaconess Medical Center Kathryn Stephenson