Nonreceptor tyrosine phosphatases (NTPs) play an important role regulating protein phosphorylation and have been proposed as attractive therapeutic targets for cancer and metabolic diseases. We have previously identified that 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (HODHBt) enhanced STAT activation upon cytokine stimulation leading to increased reactivation of latent HIV and effector functions of NK and CD8 T cells. Here, we demonstrated that HODHBt interacts with and inhibits the NTPs PTPN1 and PTPN2 through a mixed inhibition mechanism. We also confirmed that PTPN1 and PTPN2 specifically control the phosphorylation of different STATs. The small molecule ABBV-CLS-484 (AC-484) is an active site inhibitor of PTPN1 and PTPN2 currently in clinical trials for advanced solid tumors. We compared AC-484 and HODHBt and found similar effects on STAT5 and immune activation albeit with different mechanisms of action leading to varying effects on latency reversal. Our studies provide the first specific evidence that enhancing STAT phosphorylation via inhibition of PTPN1 and PTPN2 is an effective tool against HIV.
J. Natalie Howard, Thomas D. Zaikos, Callie Levinger, Esteban Rivera, Elyse K. McMahon, Carissa S. Holmberg, Joshua Terao, Marta Sanz, Dennis C. Copertino Jr., Weisheng Wang, Natalia Soriano-Sarabia, R. Brad Jones, Alberto Bosque
Current antiretroviral therapy (ART) regimens efficiently limit HIV replication, thereby improving life expectancy of people living with HIV, but also cause metabolic side effects. The ongoing obesity epidemic has resulted in more people with metabolic comorbidities at the time of HIV infection, yet the impact of pre-existing metabolic dysregulation on infection sequelae and response to ART is unclear. Here, to investigate the impact of preexisting obesity and insulin resistance on acute infection and subsequent long-term ART, we infected a cohort of lean and obese adult male macaques with SIV and administered ART. The responses of lean and obese macaques to SIV and ART were similar with respect to plasma and cell-associated viral loads, ART drug levels in plasma and tissues, SIV-specific immune responses, adipose tissue and islet morphology, and colon inflammation, with baseline differences between lean and obese groups largely maintained. Both groups exhibited a striking depletion of CD4+ T cells from adipose tissue that did not recover with ART. However, differential responses to SIV and ART were observed for body weight, omental adipocyte size, and the adiponectin/leptin ratio, a marker of cardiometabolic risk. Thus, obesity and insulin resistance had limited effects on multiple responses to acute SIV infection and ART, while several factors that underlie long-term metabolic comorbidities were influenced by prior obesity and insulin resistance. These studies provide the foundation for future investigations into the efficacy of adjunct therapies such as metformin and glucagon-like peptide-1 receptor agonists in the prevention of metabolic comorbidities in people living with HIV.
Gabriela M. Webb, Kristin A. Sauter, Diana Takahashi, Melissa Kirigiti, Lindsay Bader, Sarah R. Lindsley, Hannah M. Blomenkamp, Cicely Zaro, Molly Shallman, Casey M. McGuire, Heather Hofmeister, Uriel Avila, Cleiton Pessoa, Joseph M. Hwang, Allyson J. McCullen, Matthew Humkey, Jason Reed, Lina Gao, Lee Winchester, Courtney V. Fletcher, Oleg Varlamov, Todd T. Brown, Jonah B. Sacha, Paul Kievit, Charles T. Roberts
BACKGROUND. An HIV-1 DNA vaccine composed of seven highly conserved, structurally important elements (Conserved Elements, CE) of HIV p24Gag was tested in a phase I randomized, double-blind clinical trial (HVTN 119, NCT03181789) in people without HIV. A CE prime- CE+full-length p55Gag boost DNA vaccine was compared to p55Gag DNA vaccination only. METHODS. Two groups (n=25 each) received 4 DNA vaccinations [2xCE prime- 2xCE+p55Gag boost or 4x p55Gag] by intramuscular injection/electroporation, including IL-12 DNA adjuvant. The placebo group (n=6) received saline. Participants were followed for safety and tolerability. Immunogenicity was assessed for T cell and antibody responses. RESULTS. Both regimens were safe and generally well-tolerated. The p24CE vaccine was immunogenic (29% CD4+ and 4% CD8+ responders) and was significantly boosted by CE+p55Gag (64% CD4+, p=0.037; 42% CD8+, p=0.004). CE+p55Gag induced CD4+ responses to 5 of 7 CE, compared to only 2 CE by p55Gag DNA alone, with a higher reponse to CE5 in 30% of individuals (p=0.006). CE+p55Gag induced significantly higher mean CD4+ CE Tcell breadth (0.68 vs 0.22 CE; p=0.029) and a strong trend for increased CD4+ and CD8+ T-cell breadth (1.14 vs. 0.52 CE; p=0.051) compared to p55Gag alone. Both groups developed high p55Gag T-cell (91% each) and p24Gag antibody (91% vs. 80%) responses. p24CE vaccine-induced CD4+ CE T-cell responses correlated (p=0.007) with p24Gag antibody responses. CONCLUSION. The combination CE/CE+p55Gag DNA vaccine induced T-cell immune responses to conserved regions in p24Gag resulting in significant increases in breadth and epitope recognition throughout p55Gag. Vaccines able to focus immune responses by priming responses to highly conserved regions could be part of a comprehensive HIV vaccine strategy. TRIAL REGISTRATION. Clinical Trials.gov NCT03181789 Study URL: https://www.clinicaltrials.gov/search?term=NCT03181789 FUNDING. HIV vaccine trial network (HVTN), NIAID/NIH
Spyros A. Kalams, Barbara K. Felber, James I. Mullins, Hyman M. Scott, Mary A. Allen, Stephen C. De Rosa, Jack Heptinstall, Georgia D. Tomaras, Jiani Hu, Allan C. deCamp, Margherita Rosati, Jenifer Bear, Michael N. Pensiero, John Eldridge, Michael A. Egan, Drew Hannaman, M. Juliana McElrath, George N. Pavlakis
The role of different biological variables including biological sex, age, and sex hormones in HIV cure approaches is not well understood. The γc-cytokine IL-15 is a clinically relevant cytokine that promotes immune activation and mediates HIV reactivation from latency. In this work, we examine the interplay that biological sex, age, and sex hormones 17β-estradiol, progesterone, and testosterone may have on the biological activity of IL-15. We found that IL-15-mediated CD4 T cell activation was higher in female donors compared to male donors. This difference was abrogated at high 17β-estradiol concentration. Additionally, there was a positive correlation between age and both IL-15-mediated CD8 T cell activation and IFN-γ production. In a primary cell model of latency, biological sex, age, or sex hormones did not influence the ability of IL-15 to reactivate latent HIV. Finally, 17β-estradiol did not consistently affect reactivation of translation-competent reservoirs in CD4 T cells from ART-suppressed people living with HIV. Our study has found that biological sex and age, but not sex hormones, may influence some of the biological activities of IL-15. Understanding how different biological variables affect the biological activity of cure therapies will help us evaluate current and future clinical trials aimed towards HIV cure in diverse populations.
Carissa S. Holmberg, Callie Levinger, Marie Abongwa, Cristina Ceriani, Nancie Archin, Marc Siegel, Mimi Ghosh, Alberto Bosque
We evaluated the safety and viral rebound, after analytical treatment interruption (ATI), of vedolizumab and ART in recent HIV-1 infection. We used this model to analyze the impact of α4β7 on the HIV-1 reservoir size. Participants started ART with monthly Vedolizumab infusions and ATI was performed at week 24. Biopsies were obtained from ileum and caecum at baseline and week 24. Vedolizumab levels, HIV-1 reservoir, flow cytometry and cell-sorting and antibody competition experiments were assayed. Vedolizumab was safe and well-tolerated. No participant achieved undetectable viremia off ART 24 weeks after ATI. Only a modest effect on the time to achieve >1000 HIV-RNA copies/mL and the proportion of participants off ART was observed, being higher compared to historical controls. Just before ATI, α4β7 expression was associated with HIV-1 DNA and RNA in peripheral blood and with PD1 and TIGIT levels. Importantly, a complete blocking of α4β7 was observed on peripheral CD4+ T-cells but not in gut (ileum and caecum), where α4β7 blockade and vedolizumab levels were inversely associated with HIV-1 DNA. Our findings support α4β7 as an important determinant in HIV-1 reservoir size, suggesting the complete α4β7 blockade in tissue as a promising tool for HIV-cure combination strategies.
Maria Reyes Jimenez-Leon, Carmen Gasca-Capote, Cristina Roca-Oporto, Nuria Espinosa, Salvador Sobrino, Maria Fontillon-Alberdi, Ce Gao, Isabelle Roseto, Gregory Gladkov, Inmaculada Rivas-Jeremias, Karin Neukam, Jose German Sanchez-Hernandez, Raul Rigo-Bonnin, Antonio J. Cervera-Barajas, Rosario Mesones, Federico García, Ana Isabel Alvarez-Rios, Sara Bachiller, Joana Vitalle, Alberto Perez-Gomez, María Inés Camacho-Sojo, Isabel Gallego, Christian Brander, Ian McGowan, Beatriz Mothe, Pompeyo Viciana, Xu Yu, Mathias Lichterfeld, Luis F. Lopez-Cortes, Ezequiel Ruiz-Mateos
Identifying immune correlates of protection is a major challenge in AIDS vaccine development. Anti-Envelope antibodies have been considered critical for protection against SIV/HIV (SHIV) acquisition. Here, we evaluated the efficacy of an SHIV vaccine against SIVmac251 challenge, where the role of antibody was excluded, as there was no cross-reactivity between SIV and SHIV envelope antibodies. After 8 low-dose intrarectal challenges with SIVmac251, 12 SHIV-vaccinated animals demonstrated efficacy, compared with 6 naive controls, suggesting protection was achieved in the absence of anti-envelope antibodies. Interestingly, CD8+ T cells (and some NK cells) were not essential for preventing viral acquisition, as none of the CD8-depleted macaques were infected by SIVmac251 challenges. Initial investigation of protective innate immunity revealed that protected animals had elevated pathways related to platelet aggregation/activation and reduced pathways related to interferon and responses to virus. Moreover, higher expression of platelet factor 4 on circulating platelet-leukocyte aggregates was associated with reduced viral acquisition. Our data highlighted the importance of innate immunity, identified mechanisms, and may provide opportunities for novel HIV vaccines or therapeutic strategy development.
Yongjun Sui, Thomas J. Meyer, Christine M. Fennessey, Brandon F. Keele, Kimia Dadkhah, Chi Ma, Celia C. LaBranche, Matthew W. Breed, Josh A. Kramer, Jianping Li, Savannah E. Howe, Guido Ferrari, LaTonya D. Williams, Maggie Cam, Michael C. Kelly, Xiaoying Shen, Georgia D. Tomaras, David Montefiori, Tim F. Greten, Christopher J. Miller, Jay A. Berzofsky
Antibody-mediated depletion studies have demonstrated that CD8+ T cells are required for effective immune control of SIV. However, this approach is confounded by several factors, including reactive CD4+ T cell proliferation, and further provides no specificity information. We circumvented these limitations by selectively depleting CD8+ T cells specific for the Gag epitope CTPYDINQM (CM9) via the administration of immunotoxin-conjugated tetrameric complexes of CM9/Mamu-A*01. Immunotoxin administration effectively depleted circulating but not tissuelocalized CM9-specific CD8+ T cells, akin to the bulk depletion pattern observed with antibodies directed against CD8. However, we found no evidence to indicate that circulating CM9-specific CD8+ T cells suppressed viral replication in Mamu-A*01+ rhesus macaques during acute or chronic progressive infection with a pathogenic strain of SIV. This observation extended to macaques with established infection during and after continuous antiretroviral therapy. In contrast, natural controller macaques experienced dramatic increases in plasma viremia after immunotoxin administration, highlighting the importance of CD8+ T cell-mediated immunity against CM9. Collectively, these data showed that CM9-specific CD8+ T cells were necessary but not sufficient for robust immune control of SIV in a nonhuman primate model and, more generally, validated an approach that could inform the design of next-generation vaccines against HIV-1.
Jennifer Simpson, Carly E. Starke, Alexandra M. Ortiz, Amy Ransier, Sam Darko, Sian Llewellyn-Lacey, Christine M. Fennessey, Brandon F. Keele, Daniel C. Douek, David A. Price, Jason M. Brenchley
The most common subtype of lymphoma globally, diffuse large B-cell lymphoma (DLBCL) is a leading cause of cancer death in people with HIV (HIV+). The restructuring of the T-cell compartment due to HIV infection and antiretroviral therapy (ART) may have implications for modern treatment selection, but current understanding of these dynamic interactions is limited. Here, we investigated the T-cell response to DLBCL by sequencing the T-cell receptor (TCR) repertoire in a cohort of HIV-negative (HIV-), HIV+/ART-experienced and HIV+/ART-naïve DLBCL patients. HIV+/ART-naïve tumor TCR repertoires were more clonal and more distinct from each other than HIV- and HIV+/ART-experienced. Further, increased overlap between tumor and blood TCR repertoires was associated with improved survival and HIV/ART status. Our study describes TCR repertoire characteristics for the first time in an African DLBCL cohort and demonstrates contributions of HIV infection and ART exposure to the DLBCL TCR repertoire.
Sophia M. Roush, Jenny Coelho, Alexander M. Xu, Kaushik Puranam, Marriam Mponda, Edwards Kasonkanji, Maurice Mulenga, Tamiwe Tomoka, Jonathan Galeotti, Amy Brownlee, Hormas Ghadially, Maganizo Chagomerana, Blossom Damania, Matthew Painschab, Akil Merchant, Satish Gopal, Yuri Fedoriw
Children with perinatally acquired HIV (PHIV) have special vaccination needs, as they make suboptimal immune responses. Here, we evaluated safety and immunogenicity of 2 doses of 4-component group B meningococcal vaccine in antiretroviral therapy–treated children with PHIV and healthy controls (HCs). Assessments included the standard human serum bactericidal antibody (hSBA) assay and measurement of IgG titers against capsular group B Neisseria meningitidis antigens (fHbp, NHBA, NadA). The B cell compartment and vaccine-induced antigen-specific (fHbp+) B cells were investigated by flow cytometry, and gene expression was investigated by multiplexed real-time PCR. A good safety and immunogenicity profile was shown in both groups; however, PHIV demonstrated a reduced immunogenicity compared with HCs. Additionally, PHIV showed a reduced frequency of fHbp+ and an altered B cell subset distribution, with higher fHbp+ frequency in activated memory and tissue-like memory B cells. Gene expression analyses on these cells revealed distinct mechanisms between PHIV and HC seroconverters. Overall, these data suggest that PHIV presents a diverse immune signature following vaccination. The impact of such perturbation on long-term maintenance of vaccine-induced immunity should be further evaluated in vulnerable populations, such as people with PHIV.
Nicola Cotugno, Alessia Neri, Marco Sanna, Veronica Santilli, Emma Concetta Manno, Giuseppe Rubens Pascucci, Elena Morrocchi, Donato Amodio, Alessandra Ruggiero, Marta Luisa Ciofi degl Atti, Irene Barneschi, Silvia Grappi, Ilaria Cocchi, Vania Giacomet, Daria Trabattoni, Giulio Olivieri, Stefania Bernardi, Daniel O’Connor, Emanuele Montomoli, Andrew J. Pollard, Paolo Palma
The central nervous system HIV reservoir is incompletely understood and is a major barrier to HIV cure. We profiled people with HIV (PWH) and uninfected controls through single-cell transcriptomic and T cell receptor (TCR) sequencing to understand the dynamics of HIV persistence in the CNS. In PWH on ART, we found that most participants had single cells containing HIV-1 RNA, which was found predominantly in CD4 central memory T cells, in both cerebrospinal fluid (CSF) and blood. HIV-1 RNA–containing cells were found more frequently in CSF than blood, indicating a higher burden of reservoir cells in the CNS than blood for some PWH. Most CD4 T cell clones containing infected cells were compartment specific, while some (22%) — including rare clones with members of the clone containing detectable HIV RNA in both blood and CSF — were found in both CSF and blood. These results suggest that infected T cells trafficked between tissue compartments and that maintenance and expansion of infected T cell clones contributed to the CNS reservoir in PWH on ART.
Meng Wang, Jennifer Yoon, Hailey Reisert, Bibhuprasad Das, Benjamin Orlinick, Jennifer Chiarella, Elias K. Halvas, John Mellors, Alina P.S. Pang, Lydia Aoun Barakat, Margaret Fikrig, Joshua Cyktor, Yuval Kluger, Serena Spudich, Michael J. Corley, Shelli F. Farhadian
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