Background Given the high mortality rate for those with end-stage kidney d sease on dialysis and the efficacy and safety of current hepatitis C virus (HCV) treatments, currently-discarded kidneys from HCV-infected (HCV+) donors may be a neglected public health resource. Objective To determine the tolerability and feasibility of kidney transplantation (KT) from HCV+ donors to HCV-uninfected recipients (HCV D+/R−) in combination with direct-acting antivirals (DAAs) as pre- and post-transplant prophylaxis. Design Open-label, non-randomized trial. (ClinicalTrials.gov: NCT02781649) Setting Single-center. Participants 10 HCV-uninfected KT candidates over the age of 50 years with no available living donors. Intervention KT from deceased donors ages 13–50 years with a positive HCV RNA and HCV antibody test. All recipients received a dose of grazoprevir 100 mg/elbasvir 50 mg (GZR/EBR) immediately prior to transplant. For genotype 1 donors, recipients continued GZR/EBR for 12 weeks post-transplant; for genotype 2 or 3 donors, sofosbuvir 400 mg was added to GZR/EBR for 12 weeks of triple-therapy. Measurements The primary safety outcome was the incidence of adverse events related to GZR-EBR. The primary efficacy outcome was the proportion recipients with HCV RNA less than the lower limit of quantification 12 weeks after prophylaxis. Results Among 10 HCV D+/R− there were no treatment-related adverse events and HCV RNA was not detected in any recipient 12 weeks after treatment. Limitations Nonrandomized study design and small number of patients. Conclusions Pre- and post-transplant HCV treatment was safe and prevented chronic hepatitis C in HCV D+/R− KT. If confirmed in larger studies, this strategy should markedly expand organ options and reduce mortality for HCV− KT candidates.

A DNA-based vaccine containing human immunodeficiency virus type 1 (HIV-1) env and rev genes was tested for safety and host immune response in 15 asymptomatic HIV-infected patients who were not using antiviral drugs and who had CD4+ lymphocyte counts of > or = 500 per microliter of blood. Successive groups received three doses of vaccine (30, 100, or 300 microg) at 10-week intervals in a dose-escalation trial. Vaccine administration induced no local or systemic reactions, and no laboratory abnormalities were detected. Specifically, no patient developed anti-DNA antibody or muscle enzyme elevations. No consistent change occurred in CD4 or CD8 lymphocyte counts or in plasma HIV concentration. Antibody against gp120 increased in individual patients in the 100- and 300-/microg groups. Some increases were noted in cytotoxic T lymphocyte activity against gp160-bearing targets and in lymphocyte proliferative activity. The safety and potential immunogenicity of an HIV-directed DNA-based vaccine was demonstrated, a finding that should encourage further studies.

Programmed Death-1 (PD-1) is a co-inhibitory receptor that down-regulates the activity of tumor-infiltrating lymphocytes (TIL) in cancer and of virus-specific T cells in chronic infection. The molecular mechanisms driving high PD-1 expression on TIL have not been fully investigated. We demonstrate that transforming growth factor-β1 (TGF-β1) directly enhances antigen-induced PD-1 expression through Smad3-dependent, Smad2-independent transcriptional activation in T cells in vitro and in TIL in vivo. The PD-1hi subset seen in CD8+ TIL is absent in Smad3-deficient tumor-specific CD8+ TIL, resulting in enhanced cytokine production by TIL and in draining lymph nodes and of anti-tumor activity. In addition to TGF-β1’s previously known effects on T cell function, our findings suggest that TGF-β1 mediates T cell suppression via PD-1 upregulation in the TME. They highlight bidirectional crosstalk between effector TIL and TGF-β-producing cells that upregulates multiple components of the PD-1 signaling pathway to inhibit anti-tumor immunity.

Innate immune sensing of viral infection results in type I interferon (IFN) production and inflammasome activation. Type I IFNs, primarily IFN-α and IFN-β, are produced by all cell types upon virus infection and promote an antiviral state in surrounding cells by inducing the expression of IFN-stimulated genes. Type I IFN production is mediated by Toll-like receptor (TLR) 3 in HCV infected hepatocytes. Type I IFNs are also produced by plasmacytoid dendritic cells (pDC) after sensing of HIV and HCV through TLR7 in the absence of productive pDC infection. Inflammasomes are multi-protein cytosolic complexes that integrate several pathogen-triggered signaling cascades ultimately leading to caspase-1 activation and generation pro-inflammatory cytokines including interleukin (IL)-18 and IL-1β. Here, we demonstrate that HIV and HCV activate the inflammasome, but not Type I IFN production, in monocytes and macrophages in an infection-independent process that requires clathrin-mediated endocytosis and recognition of the virus by distinct endosomal TLRs. Knockdown of each endosomal TLR in primary monocytes by RNA interference reveals that inflammasome activation in these cells results from HIV sensing by TLR8 and HCV recognition by TLR7. Despite its critical role in type I IFN production by pDCs stimulated with HIV, TLR7 is not required for inflammasome activation by HIV. Similarly, HCV activation of the inflammasome in monocytes does not require TLR3 or its downstream signaling adaptor TICAM-1, while this pathway leads to type I IFN in infected hepatocytes. Monocytes and macrophages do not produce type I IFN upon TLR8 or TLR7 sensing of HIV or HCV, respectively. These findings reveal a novel infection-independent mechanism for chronic viral induction of key anti-viral programs and demonstrate distinct TLR utilization by different cell types for activation of the type I IFN vs. inflammasome pathways of inflammation.