The latency-reversing agent HODHBt synergizes with IL-15 to enhance cytotoxic function of HIV-specific T cells.

IL-15 is under clinical investigation toward the goal of curing HIV infection because of its abilities to reverse HIV latency and enhance immune effector function. However, increased potency through combination with other agents may be needed. 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (HODHBt) enhances IL-15-mediated latency reversal and NK cell function by increasing STAT5 activation. We hypothesized that HODHBt would also synergize with IL-15, via STAT5, to directly enhance HIV-specific cytotoxic T cell responses. We showed that ex vivo IL-15 + HODHBt treatment markedly enhanced HIV-specific granzyme B-releasing T cell responses in PBMCs from antiretroviral therapy-suppressed (ART-suppressed) donors. We also observed upregulation of antigen processing and presentation in CD4+ T cells and increased surface MHC-I. In ex vivo PBMCs, IL-15 + HODHBt was sufficient to reduce intact proviruses in 1 of 3 ART-suppressed donors. Our findings reveal the potential for second-generation IL-15 studies incorporating HODHBt-like therapeutics. Iterative studies layering on additional latency reversal or other agents are needed to achieve consistent ex vivo reservoir reductions.

Antibody and T-cell responses to coronavirus disease 2019 vaccination in common variable immunodeficiency and specific antibody deficiency.

BACKGROUND: Clinical trials of the mRNA coronavirus disease 2019 (COVID-19) vaccines excluded individuals with primary antibody deficiencies. OBJECTIVE: To evaluate whether antibody and T-cell responses to mRNA COVID-19 vaccination in patients with common variable immunodeficiency (CVID) and specific antibody deficiency (SAD) were comparable to those in healthy controls. METHODS: We measured antibody responses against the spike glycoprotein and the receptor-binding domain (RBD) in addition to severe acute respiratory syndrome coronavirus 2 specific T-cell responses using peripheral blood mononuclear cells 2 to 8 weeks after the subjects completed the primary 2-dose vaccine series. RESULTS: The study comprised 12 patients with CVID, 7 patients with SAD, and 10 controls. Individuals with CVID had lower immunoglobulin (Ig) G and Ig A levels against spike glycoprotein than did both individuals with SAD (P = .27 and P = .01, respectively) and controls (P = .01 and P = .004, respectively). The CVID group developed lower IgG titers against the RBD epitope than did the control group (P = .01). Participants with CVID had lower neutralizing titers than did the control group (P = .002). All participants with SAD developed neutralizing titers. All 3 groups (SAD, CVID, and control) developed antigen-specific CD4+ and CD8+ T-cell responses after vaccination. CONCLUSION: Our results suggest that patients with CVID may have impaired antibody responses to COVID-19 vaccination but intact T-cell responses, whereas patients with SAD would be expected to have both intact antibody and T-cell responses to vaccination.

PolyIC-coated Prussian blue nanoparticles as a dual-mode HIV latency reversing agent.

Aim: To investigate Prussian blue nanoparticles (PBNPs) coated with the synthetic analog of dsRNA polyinosinic-polycytidylic acid (polyIC) for their ability to function as HIV latency reversing agents. Methods: A layer-by-layer method was used to synthesize polyIC-coated PBNPs (polyIC-PBNPs). PolyIC-PBNPs were stable and monodisperse, maintained the native absorbance properties of both polyIC and PBNPs and were obtained with high nanoparticle collection yield and polyIC attachment efficiencies. Results: PolyIC-PBNPs were more effective in reactivating latent HIV than free polyIC in a cell model of HIV latency. Furthermore, polyIC-PBNPs were more effective in promoting immune activation than free polyIC in CD4 and CD8 T cells. Conclusion: PBNPs function as efficient carriers of nucleic acids to directly reverse HIV latency and enhance immune activation.

HIV is a virus that attacks and weakens the immune system. If left untreated, HIV infection leads to AIDS. To combat this, administration of antiretroviral therapy allows HIV to be controlled, and an infected individual may live a normal life. However, there is no cure for HIV because the virus persists within hidden reservoirs of latently infected cells that remain undetected by the immune system. A cure strategy currently under investigation in the field utilizes a latency reversing agent (LRA) to reactivate latent HIV with the goal of promoting a response from the immune system. To achieve this goal, this study used a nanoparticle-based method to administer LRAs. More specifically, the authors synthesized Prussian blue nanoparticles (PBNPs) coated with the LRA polyinosinic-polycytidylic acid (polyIC), a synthetic analog of dsRNA. This study demonstrates that when administered in the form of nanoparticles, polyIC-coated PBNPs generate both enhanced reactivation of HIV and immune activation when compared with free polyIC. These results indicate a promising potential for using PBNPs to deliver LRAs such as polyIC to enhance current and future HIV cure strategies.