CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

297 LILRA3 Deletion Is a Genetic Risk Factor of HIV Infection Gerrit Ahrenstorf 1 ; Hui Zhi Low 1 ; Katja kniesch 1 ; Matthias Stoll 1 ; Dirk Meyer-Olson 1 ;Torsten Matthias 2 ; Reinhold E. Schmidt 1 ;TorstenWitte 1 1 Hannover Medical School, Hannover, Germany; 2 AESKU Diagnostics, Wendelsheim, Germany

Background: Both the risk of transmission of HIV and the clinical course of the disease are influenced by viral pathogenicity as well as host factors. LILRA3 a protein of the leukocyte immunoglobulin-like receptor family exerts various immunmodulatory functions. A naturally occuring 6.7 kbp deletion in the gene locus of LILRA3 results in a null allele and an absence of the protein. The influence of LILRA3 and of the genetic LILRA3 deletion on the transmission and the clinical course of HIV infection was analyzed in this study. Methods: LILRA3 genotypes were determined by polymerase chain reaction. HIV infected patients that were followed for at least 24 months were categorized into short-term progressors, normal progressors and long-term non-progressors according to the clinical and immunological course. Studies of LILRA3 gene regulation and protein concentrations were performed using real-time PCR, intracellular flow cytometry and ELISA. Results: The prevalence of homozygous LILRA3 deletion was significantly higher in HIV positive individuals (n= 415) than in controls (n= 615) (p= 0.02). The progression of the disease was faster in patients with homozygous LILRA3 deletion with a higher proportion of short-term progressors among homozygously deleted patients than in heterozygous (p= 0.03) and in homozygously positive (p=0.002) individuals. The relative risk for a faster progression was 1.5 times higher in heterozygous individuals and 3 times in homozygously LILRA3 negative individuals when compared to homozygously positive ones. Functional analysis revealed an upregulation of the LILRA3 gene in Real-time PCR in treated HIV patients when compared to untreated patients (p= 0.007) and controls (p= 0.02) resulting in a higher LILRA3 expression in CD4 + (p= 0.008) and CD14 + (p= 0.02) cells of untreated patients than in controls in intracellular flow cytometry. LILRA3 concentrations in the sera were similar between the groups, in untreated patients a correlation between viral load and LILRA3 concentration was found. Conclusions: The homozygous LILRA3 deletion is associated with a higher susceptibility for HIV disease and with a faster disease progression in HIV infected individuals. 298LB SIV Infection Triggers Endothelial Dysfunction and Diminished Expression of Krüppel-Like Factor 2 (KLF2) in Nonhuman Primates Soumya Panigrahi 1 ; Michael L. Freeman 1 ; joseph C. mudd 4 ; Nicholas Funderburg 2 ; Scott Sieg 1 ; David A. Zidar 1 ; Mirko Paiardini 3 ; FrancoisVillinger 3 ; Mukesh K. Jain 1 ; michael lederman 1 1 Case Western Reserve University/University Hospitals Medical Center, Cleveland, OH, US; 2 Ohio State University School of Health and Rehabilitation Sciences, Columbus, OH, US; 3 Emory University, Atlanta, GA, US; 4 Lab of Molecular Microbiology, Bethesda, MD, US Background: Life-saving, long-term anti-retroviral therapy (ART) is linked to increased risk of thromboembolism and cardiovascular co-morbidities. While immune activation, bacterial translocation, oxidative stress, and chronic vascular inflammation are the prime predicted triggering factors, a through mechanistic knowledge is still lacking. Here, we examined endothelium of SIV infected Rhesus macaque with the hypothesis that key markers of endothelial dysfunction and expression of Krüppel-like factor 2 (KLF2), a transcriptional master regulator of an anti-thrombotic endothelial environment, will be modulated. Methods: Sections of paraffin-embedded thorasic aorta from SIV (SHIVSF162P3) infected and uninfected Rhesus macaques were used in this study. H&E staining to identify any morphological alteration or sub-endothelial infiltration of inflammatory cells and immunohistochemistry methods were applied to detect endothelial eNOS and KLF2 expression by epi-fluorescent microscopy (EVOS ® FL). Public domain software ImageJ v1.38e was used for the digital image data analysis. We also investigated the in vitro effect of statin on KLF2 expression in human aortic endothelial cells. Results: Focal endothelial proliferation, and sub-endothelial infiltrations at multiple sites were found in H&E stained sections of 3 out of 4 infected animals, compared to none in the 22 controls. This observation was further refined by immune-fluorescence detection of sub-endothelial monocytes (CD68+), T lymphocytes (CD8+), and platelets (CD41+) in the infected group. We observed significant reduction (p < 0.001) of eNOS expression in all 4 infected animals (Fig 1a). We also detected significantly lower (p < 0.0001) KLF2 expression in the endothelium of the infected animals (Fig 1b). Moreover, our results indicate that simvastatin protects human aortic endothelial cells from LPS and oxLDL induced down-regulation of KLF2.

Poster Abstracts

Figure1. Endothelial Dysfunction and reduced Krüppel-like Factor expression in SIV infection: A. Endothelial eNOS B. Endothelial KLF2 (cumulative data from 100 endothelial cells in each aortic section of 4 infected and 4 control animals). Conclusions: Here we show for the first time direct evidence that SIV infected Rhesus macaques have dysfunctional vascular endotheliumwith sub-endothelial infiltration of inflammatory cells indicating early atherosclerotic changes. We also report for the first time a significant down-regulation of endothelial KLF2 in SIV infected animals. In addition, while lipid dysregulation and bacterial translocation may prime the initiation and maintenance of a pro-thrombotic endothelium in HIV infection, our in vitro data indicate that statin can protect endothelial cells from LPS and oxLDL induced KLF2 down-regulation. 299LB A Novel Method Using 2 H 2 O to Measure Collagen Turnover in HIV-Infected Individuals Leslie R. Cockerham 1 ; Claire Emson 2 ; Ma Somsouk 1 ; Kara Harvill 1 ; Kevin Li 2 ; Scott M.Turner 2 ; Martin L. Decaris 2 ; Marc K. Hellerstein 3 ; Steven G. Deeks 1 ; Hiroyu Hatano 1 1 University of California San Francisco, San Francisco, CA, US; 2 KineMed, Inc, Emeryville, CA, US; 3 University of California Berkeley, Berkeley, CA, US Background: Lymphoid tissue fibrosis occurs early in HIV infection and is thought to be a central factor in the pathogenesis of HIV by impairing T cell homeostasis. Collagen deposition is a dynamic process, and traditional histologic techniques cannot distinguish between new collagen deposition and any fibrosis that may have accumulated during the untreated phase of HIV infection. We investigated the use of a technique utilizing 2 H 2 O (heavy water) intake to quantify new collagen deposition in gut-associated lymphoid tissue (GALT) in treated HIV-infected individuals. Methods: Eighteen HIV-infected individuals on suppressive ART received outpatient oral doses of 2 H 2 O for 4 weeks and underwent colorectal biopsies. 2 H 2 O enrichment in total body water (TBW) in each patient was quantified fromweekly salivary swabs during 2 H 2 O administration. Single 3mm biopsy pieces were subjected to sequential physical and

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CROI 2015