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The presence of persistent, latent HIV reservoirs in [CD4.sup.+] T cells obstructs current efforts to cure infection. The so-called kick-and-kill paradigm proposes to purge these reservoirs by combining latency-reversing agents with immune effectors such as cytotoxic T lymphocytes. Support for this approach is largely based on success in latency models, which do not fully reflect the makeup of latent reservoirs in individuals on long-term antiretroviral therapy (ART). Recent studies have shown that [CD8.sup.+] T cells have the potential to recognize defective proviruses, which comprise the vast majority of all infected cells, and that the proviral landscape can be shaped over time due to in vivo clonal expansion of infected [CD4.sup.+] T cells. Here, we have shown that treating [CD4.sup.+] T cells from ART-treated individuals with combinations of potent latency-reversing agents and autologous [CD8.sup.+] T cells consistently reduced cell-associated HIV DNA, but failed to deplete replication-competent virus. These [CD8.sup.+] T cells recognized and potently eliminated [CD4.sup.+] T cells that were newly infected with autologous reservoir virus, ruling out a role for both immune escape and [CD8.sup.+] T cell dysfunction. Thus, our results suggest that cells harboring replication-competent HIV possess an inherent resistance to [CD8.sup.+] T cells that may need to be addressed to cure infection., Introduction Eradicating latent HIV reservoirs will require the elimination of persistent populations of cells with integrated HIV proviruses. The major barrier impeding viral eradication is thought to be a reservoir [...]

MicroRNAs (miRNAs) are noncoding RNAs that regulate posttranscriptional gene expression. In this study we characterized the circulating and urinary miRNA pattern associated with reduced glomerular filtration rate, using Affymetrix GeneChip miR 4.0 in 28 patients with chronic kidney disease (CKD). Top miRNA discoveries from the human studies were validated in an Alb/TGF β mouse model of CKD, and in rat renal proximal tubular cells (NRK52E) exposed to TGFβ1. Plasma and urinary levels of procollagen III N-terminal propeptide and collagen IV were elevated in patients with decreased estimated glomerular filtration rate (eGFR). Expression of 384 urinary and 266 circulatory miRNAs were significantly different between CKD patients with eGFR ≥30 vs. <30 ml⋅min-1⋅1.73 m-2. Pathway analysis mapped multiple miRNAs to TGFβ signaling-related mRNA targets. Specifically, Let-7a was significantly downregulated, and miR-130a was significantly upregulated, in urine of patients with eGFR <30; miR-1825 and miR-1281 were upregulated in both urine and plasma of patients with decreased eGFR; and miR-423 was significantly downregulated in plasma of patients with decreased eGFR. miRNA expression in urine and plasma of Alb/TGFβ mice generally resembled and confirmed most, although not all, of the observations from the human studies. In response to TGFβ1 exposure, rat renal proximal tubular cells overexpressed miR-1825 and downregulated miR-423. Thus, miRNA are associated with kidney fibrosis, and specific urinary and plasma miRNA profile may have diagnostic and prognostic utility in CKD. [ABSTRACT FROM AUTHOR]

Resting CD4+ T-cells harboring inducible HIV proviruses are a critical reservoir in antiretroviral therapy (ART)-treated subjects. These cells express little to no viral protein, and thus neither die by viral cytopathic effects, nor are efficiently cleared by immune effectors. Elimination of this reservoir is theoretically possible by combining latency-reversing agents (LRAs) with immune effectors, such as CD8+ T-cells. However, the relative efficacy of different LRAs in sensitizing latently-infected cells for recognition by HIV-specific CD8+ T-cells has not been determined. To address this, we developed an assay that utilizes HIV-specific CD8+ T-cell clones as biosensors for HIV antigen expression. By testing multiple CD8+ T-cell clones against a primary cell model of HIV latency, we identified several single agents that primed latently-infected cells for CD8+ T-cell recognition, including IL-2, IL-15, two IL-15 superagonists (IL-15SA and ALT-803), prostratin, and the TLR-2 ligand Pam3CSK4. In contrast, we did not observe CD8+ T-cell recognition of target cells following treatment with histone deacetylase inhibitors or with hexamethylene bisacetamide (HMBA). In further experiments we demonstrate that a clinically achievable concentration of the IL-15 superagonist ‘ALT-803’, an agent presently in clinical trials for solid and hematological tumors, primes the natural ex vivo reservoir for CD8+ T-cell recognition. Thus, our results establish a novel experimental approach for comparative evaluation of LRAs, and highlight ALT-803 as an LRA with the potential to synergize with CD8+ T-cells in HIV eradication strategies. [ABSTRACT FROM AUTHOR]