CROI 2018 Abstract eBook

Abstract eBook

Poster Abstracts

(FDR) ∠ 0.05. Ct values from endogenous controls (SNORD68, RNU6-2) were used to normalize all miRNA Ct values. Results: We found higher expression of 16 miRNAs in pTfh cells compared to Trm cells but with no difference between studied groups. In contrast, only one miRNA (miR-382-5p) was upregulated in Trm cells compared to pTfh cells. Interestingly, the single miRNA (miR-382-5p) that was overexpressed in Trm cells was found only in uninfected subjects (adjusted p value=0.048) and in EC patients (adjusted p value=0.026) and not in chronically HIV infected patients with detectable HIV loads (adjusted p value=0.837). Conclusion: Our data show that EC patients have significantly higher expression of miR-382-5p that is one of the miRNA suggested as implicated in the inhibiton of HIV-expression in primary resting CD4 T-cells through their interactions with the 3´end of HIV-RNA. This finding may reveal a new genetic host factor that confers protection from HIV replication and/or HIV latency. 198 NEF’S INFERIOR ABILITY TO DOWNREGULATE HLA-B CORRELATES WITH PLASMA VIRAL CONTROL Francis Mwimanzi 1 , Mako Toyoda 1 , Macdonald Mahiti 1 , Jaclyn Mann 2 , Jeffrey N. Martin 3 , David R. Bangsberg 4 , Mark Brockman 5 , Philip J. Goulder 6 , Frank Kirchhoff 7 , Zabrina Brumme 5 , Thumbi Ndungú 2 , Takamasa Ueno 1 1 Kumamoto University, Kumamoto, Japan, 2 KwaZulu-Natal Research Institute for TB and HIV, Durban, South Africa, 3 University of California San Francisco, San Francisco, CA, USA, 4 Oregon Health and Sciences University, Portland, OR, USA, 5 Simon Fraser University, Burnaby, BC, Canada, 6 University of Oxford, Oxford, UK, 7 Ulm University Medical Center, Ulm, Germany Background: Patient-derived HIV-1 subtype B Nef clones downregulate HLA-A more efficiently than HLA-B. However, it remains unknown whether this property is common to Nef proteins across primate lentiviruses, and how antiviral immune responses may be affected. Methods: We examined 263 Nef clones from diverse primate lentiviruses including different pandemic HIV-1 group M subtypes for their ability to downregulate MHC-A and MHC-B from the cell surface Results: Though lentiviral Nef proteins differed markedly in their absolute MHC-A and MHC-B downregulation abilities, all lentiviral Nef lineages downregulated MHC-A on average 11-32%more efficiently than MHC-B. Nef genotype/phenotype analyses in a cohort of HIV-1 subtype C-infected patients (N=168), together with site-directed mutagenesis, revealed Nef position 9 as a subtype-specific determinant of differential HLA-A versus HLA-B downregulation activity. Nef clones harboring non-consensus variants at codon 9 downregulated HLA-B (though not HLA-A) significantly better than those harboring consensus at this site, resulting in reduced recognition of infected target cells by HIV-1-specific CD8+ effector cells in vitro. Among persons expressing protective HLA class I alleles, carriage of Nef codon 9 variants was also associated with reduced ex vivo HIV-specific T-cell responses and higher plasma viral loads. Conclusion: Our results demonstrate that Nef’s inferior ability to downregulate MHC-B compared to MHC-A is conserved across primate lentiviruses, and suggest that this property influences antiviral cellular immune responses and viral control in HIV-infected individuals. 199 MODULATION OF HIV RESTRICTION FACTORS BY BLOCKING CCL2/CCR2 IN VITRO AND IN VIVO Daniela Angela Covino 1 , Maria Clementina Galluzzo 1 , Jing Lu 2 , Cristina Purificato 1 , Laura Catapano 1 , Matteo Pellegrini 2 , Maria Cristina Gauzzi 1 , Stefano Vella 1 , Eric Lefebvre 3 , Mauro Andreotti 1 , Laura Fantuzzi 1 1 Istituto Superiore di Sanità, Rome, Italy, 2 University of California Los Angeles, Los Angeles, CA, USA, 3 Allergan, Plc, South San Francisco, CA, USA Background: Residual viremia and low-grade persistent inflammation in cART-treated subjects are nowadays considered the main challenges to achieve a cure. The CCL2/CCR2 axis plays key roles in chronic inflammation in these patients. We found that CCL2 blocking by specific antibodies (Ab) in monocyte- derived macrophages (MDMs) restricts HIV replication by inhibiting viral DNA accumulation independently of SAMHD1. The aim of this study was to identify cellular factors modulated by CCL2/CCR2 blocking in vitro and in vivo and potentially involved in the restriction of HIV replication. Methods: Total RNA, extracted from uninfected and in vitro HIV-infected MDMs exposed to anti-CCL2 or control Ab, was subjected to poly (A) selection, reverse transcription, generation of cDNA libraries and sequencing on an Illumina Hiseq 2500 platform. Genes with logFC ≥1 (upregulated) or ≤-1

Background: Host restriction factors become upregulated early on in HIV infection as part of the innate immune response to suppress viral infectivity and activity of some of them, e.g. SLFN11 has been linked to non-progressive phenotype of HIV infection. Early treated cohorts comprising of patients treated during acute seroconversion are considered a promising group to reach functional cure by acquisition of non-progressive phenotype. We evaluated HIV host restriction factors and cofactors in early and late treated cohorts and compared their profile with progressive and non-progressive HIV infection to further characterize their role in controlling infection. Methods: The expression profile of seven HIV restriction factors and two cofactors (APOBEC3G, SAMHD1, BST2 (encoding TETHERIN), TRIM5, MX2, SLFN11, PAF1, PSIP1 (encoding LEDGF/p75) and NLRX1) was evaluated by qPCR in 104 HIV infected patients: patients treated during seroconversion (Early treated) or chronic infection (Late treated), long term non-progressors (LTNP), recent ART- naïve seroconverters, ART-naïve chronically infected patients and non-infected controls. Patients were recruited in Royal Free Hospital London and Ghent University Hospital. Principal Component Analysis (PCA) and Kruskal Wallis (KW) statistical analysis were performed. Results: Both, univariate and PCA analysis demonstrated completely distinctive expression pattern of restriction factors in early- and late-treated cohorts. Restriction factor and cofactor levels of early treated HIV patients were significantly upregulated in comparison to late treated patients (APOBEC3G: p<0.001; NLRX1: p<0.05; SLFN11: p<0.001; BST2: p<0.001). Interestingly, further analysis demonstrated similarities between early treated patients and LTNP, such as upregulation of SLFN11 and BST2. Furthermore, a negative correlation found in LTNP between SLFN11 expression and integrated HIV DNA, total HIV DNA and viral load (Spearman r: -0.55; -0.42; -0.7) is indicative of the role of SLFN11 in restricting HIV reservoir. Conclusion: Early treatment potentially prevents depletion of innate antiviral responses in comparison to late treated subjects. Elevated expression of SLFN11 and BST2 in LTNP and early treated subjects implies that these restriction factors actively contribute to the non-progressive phenotype in these cohorts.

Poster Abstracts

197 HOST MICRORNA MIR-382-5P MAY EXERT A PROTECTIVE EFFECT ON HIV CONTROL Marcial García 1 , Ricardo Ramos 2 , María Ángeles Navarrete 1 , Carlos Cañada 1 , Alfonso Cabello 3 , Juan Carlos López-Bernaldo 4 , Francisco Javier De La Hera 3 , Vicente Estrada 5 , Carlos Barros 6 , Clara Restrepo 1 , Manuel Fernández 3 , Miguel Górgolas 3 , José Miguel Benito 1 , Norma Rallón 1 1 Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, Spain, 2 Parque Científico de Madrid, Madrid, Spain, 3 Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain, 4 University Hospital Gregorio Marañon, Madrid, Spain, 5 Hospital Universitario Clínico San Carlos, Madrid, Spain, 6 Hospital Universitario de Móstoles, Madrid, Spain Background: It is known that host factors may regulate HIV replication. Host small regulatory RNAs (miRNAs) are among those potential host factors that can also regulate the expression of HIV RNA. However, evidence that specific miRNAs could be implicated in HIV pathogenesis is still elusive. In this study, we have evaluated the differential miRNA expression in different CD4 T-cell subsets in HIV infected individuals with different level of virological control. Methods: We have compared expression of a panel of 20 validated and potential anti-HIV miRNAs from Elite controllers (EC), HIV+ patients with detectable HIV load and HIV negative controls in CD4 T-cells with particular phenotypes: resting memory (Trm) and peripheral follicular helper (pTfh) cells. Profiling of miRNAs was performed by Real Time PCR and analyzed with StatMiner software (Applied Biosystems) applying a false discovery rate

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CROI 2018