CROI 2018 Abstract eBook

Abstract eBook

Poster Abstracts

Conclusion: Altogether, our data support continuous viral replication in SLO and an altered germinal center organization in HIV-2 infection. Their contribution to the benign HIV-2 course deserves further investigation that may reveal new strategies to control HIV reservoirs. 238 CD163+ LYMPH NODE MACROPHAGES ARE CORRELATED WITH LYMPH NODE FIBROSIS IN CHRONIC HIV Brooks I. Mitchell 1 , Fredrick Yost 1 , Glen M. Chew 1 , Michelle L. D’Antoni 1 , Ashley Marumoto 1 , Jodi Anderson 2 , Caitlin David 2 , Nancy Hanks 1 , Dominic Chow 1 , Timothy Schacker 2 , Lishomwa C. Ndhlovu 1 , Cecilia Shikuma 1 1 University of Hawaii at Manoa, Honolulu, HI, USA, 2 University of Minnesota, Minneapolis, MN, USA Background: Despite being on effective antiretroviral therapy (ART), many HIV-infected individuals have impaired reconstitution of CD4 T cells. This is partly due to the fibrosis of lymphoid tissues (LT), which impedes signals important for T cell homeostasis. Macrophages (Mφ) are key regulators of tissue remodeling and fibrosis, though their involvement in LT fibrosis during chronic HIV has yet to be defined. Methods: Inguinal lymph node (LN) excisions were performed by a board- certified surgeon on 6 virally-suppressed HIV-infected participants on ART and 4 HIV-uninfected participants recruited at the University Clinics at Kaka’ako at the John A. Burns School of Medicine. Immediately after excision, LN was divided into portions used for quantification of CD206+, CD163+, and CD169+ LN Mφ populations by multi-parametric flow cytometry and quantification of collagen fibers and CD4 T cells by IHC. Soluble markers of Mφ activation, fibrosis, and immune checkpoints were measured in cryopreserved plasma using ELISAs and Luminex. Statistical analyses performed were T-tests and Pearson correlations. Results: HIV-infected participants were older than those uninfected (median age: 59 years vs. 51; p=0.036). All participants were male and Caucasian, with no significant differences between groups. All HIV-infected participants were virally suppressed with a median current CD4 count of 538 cells/μl, nadir CD4 count of 65 cells/μl, and CD4 CD8 T cell ratio of 0.66. HIV-infected participants had higher frequencies of CD206+, CD169+, and CD163+ LN Mφ as compared to HIV-uninfected (CD206+: 0.27 vs. 0.13, p=0.087; CD169+: 0.56 vs. 0.31, p=0.136; CD163+: 0.047 vs. 0.017, p=0.286). CD163+ LN Mφ correlated with lower CD4 counts in blood (r=-0.827, p=0.042) and LN (r=-0.553, p=0.097), as well as lower CD4 CD8 T cell ratios (r=-0.833, p=0.039). CD163+ LN Mφ correlated with more collagen fibrils in LN (r=0.694, p=0.026) and higher plasma levels of fibrosis biomarkers: TGF-β1, r=805, p=0.005; TSP-1, r=0.740, p=0.014; and CICP, r=0.633, p=0.049. CD163+ LN Mφ correlated with higher plasma levels of soluble immune checkpoint receptors (sCTLA-4, r=0.767, p=0.010; sPD-1, r=0.713, p=0.021) and markers of Mφ activation (sCD163, r=0.867, p=0.001; Neopterin, r=0.736, p=0.015). Conclusion: CD163+ LN Mφ are elevated in ART-treated chronic HIV infection and correlates with limited CD4 T cell reconstitution in blood and LN. CD163+ LN Mφ may play a role in the pathogenesis of LT fibrosis and warrants further study. 239 GUT HOMING DEFECTS AND EXHAUSTION OF BLOOD TH17 AND TH1 CELLS IN HIV INFECTION Stephanie Dillon 1 , Allison J. Christians 1 , Kejun Guo 1 , Gregory Austin 1 , Alan Landay 2 , Mario Santiago 1 , Cara Wilson 1 1 University of Colorado Anschutz Medical Campus, Aurora, CO, USA, 2 Rush University Medical Center, Chicago, IL, USA Background: HIV infection and depletion of CD4 T helper (Th) cells in gut mucosal tissue are associated with microbial translocation and inflammation. We previously reported more significant depletion of Th17 than Th1 subsets in colon tissue in untreated HIV infection. Altered gut-homing by blood Th cells may be a contributing factor to overall gut Th cell depletion. Here, we investigated the gut-homing potential, activation and exhaustion states of peripheral blood CCR6+ Th17 and CXCR3+ Th1 cells and determined the colonic gene expression of specific chemokines that drive gut Th17 and Th1 homing (CCR6:CCL20; CXCR3:CXCL10). Methods: Stored PBMC and colon biopsies from 16 untreated, chronic HIV- 1-infected study participants (HIV+; median plasma viral load: 66,600 HIV-1 RNA/ml; median CD4 count: 410 cells/μl) and 13 uninfected controls (HIV-) from our previous clinical study (PMID: 24399150) were analyzed with consent. Flow cytometry was used to measure α4+β7+ (gut-homing), CD38+HLA-DR+ (activation) and PD1 expression (exhaustion) of blood CCR6+CCR4+CXCR3- (Th17) and CCR6-CCR4-CXCR3+ (Th1) memory (CD45RA-) CD4 T cells. CCL20 and

CXCL10 transcript levels were evaluated in colon tissue by RNAseq. Measures of microbial translocation (plasma bacterial LPS and LTA) were performed as part of our previous study. Non-parametric tests were undertaken. Results: Expression of α4+β7+ was higher on Th17 (p=0.01) and lower on Th1 (P=0.03) cells in HIV+ persons compared to HIV- persons. Colonic gene expression of CXCL10 was significantly higher (P=0.01) and CCL20 trended lower (P=0.1) in HIV+ versus HIV- persons. Expression of CD38+HLA-DR+ and PD1 were significantly higher on Th17 and Th1 cells in HIV+ persons (all P<0.0001). Th17 activation and exhaustion expression inversely correlated with CD4 count (R=-0.68, P=0.005; R=-0.58, P=0.02 respectively), whereas Th1 activation and exhaustion did not. Exhausted Th17 positively correlated with LPS (R=0.59, P=0.02) and LTA (R=0.64, P=0.01) and exhausted Th1 with LTA (R=0.63, P=0.01). Conclusion: Gut-homing profiles were altered on blood Th17 and Th1 cells during untreated HIV-1 infection and may result from dysregulated colonic tissue expression of chemokines necessary for their homing. Blood Th17 and Th1 cells displayed features of increased activation and exhaustion that associated with indicators of disease progression and microbial translocation. 240 VARIOUS SUBSETS OF CCR6+ CD4+ T CELLS ARE DIFFERENTIALLY TARGETED BY HIV-1 IN THE GUT Manon Nayrac 1 , Mary Requena 1 , Claire Loiseau 1 , Fatima L’Faqihi 1 , Michelle Cazabat 1 , Nicolas Carrere 2 , Bertrand Suc 2 , Jacques Izopet 1 , Pierre Delobel 1 1 INSERM, Toulouse, France, 2 CHU de Toulouse, Toulouse, France Background: HIV-1 persistence in reservoirs under combined antiretroviral therapy precludes virus eradication. HIV-1 DNA levels are higher in gut than in peripheral blood CD4+ T cells of treated HIV-1-infected subjects, suggesting a role for gut CD4+ T cells in HIV-1 persistence. CCR6+ CD4+ T cells are the main mucosal target cells for HIV-1, however, the susceptibility of the various subsets of CCR6+ CD4+ T cells to HIV-1 in the gut mucosal microenvironment remains unknown. Methods: An ex vivo model of human intestinal mucosa histocultures was used to explore the susceptibility of the various subsets of CCR6+ CD4+ T cells to HIV-1 in intestinal tisue. Small bowel biopsies from healthy subjects were cultured on gelatin sponges and infected by HIV-1 (BaL). At day 5 post-infection, mucosal mononuclear cells were isolated from the mucosal tissue. The phenotype of the CCR6+ cell subsets was characterized by flow cytometry (BD FORTESSA). Mucosal mononuclear cells were sorted by flow cytometry (BD ARIA SORP) in Th17, Th1Th17, and Th22 subsets. Total HIV-1 DNA was quantified in the sorted cells by qPCR (Biocentric; Light cycler 480 Roche). Experiments were repeated on intestinal tissue from five different donors. Results: All CCR6+ CD4+ T cell subsets express high levels of CCR5 and α4β7 integrin. Most Th1Th17 cells express CCR9 whereas only a few Th17 and Th22 cells did so. Th1Th17 cells (CXCR3+CCR4-CCR6+CD161+), Th17 cells (CXCR3- CCR4+CCR6+CD161+), and Th22 cells (CXCR3-CCR4+CCR6+CD161-CCR10+) were sorted by FACS frommucosal mononuclear cells obtained from infected intestinal histocultures and HIV-1 DNA was quantified in the sorted cells. Gut Th1Th17 cells harbored 12-fold higher levels of HIV-1 DNA than Th17 cells, and 2-fold higher levels of HIV-1 DNA than Th22 cells. Thus Th1Th17 cells appear to be the most susceptible target for HIV-1 among the CCR6+ CD4+ T cell subsets in the gut mucosa. Conclusion: In the gut microenvironment, the various subsets of CCR6+ CD4+ T cells are differentially targeted by HIV-1. Th1Th17 cells appear more susceptible to HIV-1 infection by an R5 strain than the other CCR6+ cell subsets. Differences in the transcriptional profile of the various CCR6+ subsets could account for their degree of permissivity to HIV-1 infection. 241 SHIV/SIV INFECTION PROMOTES CD8 T CELL VASCULAR INFILTRATION BY CX3CL1 AND IL-15 Bonnie Chen 1 , Soumya Panigrahi 1 , Jonathan Wyrick 1 , Stephen R. Morris 2 , Scott F Sieg 1 , Nicholas Funderburg 3 , David A. Zidar 1 , Mirko Paiardini 4 , Francois Villinger 5 , Souheil A Younes 1 , Michael M. Lederman 1 , Michael L. Freeman 1 1 Case Western Reserve University, Cleveland, OH, USA, 2 Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA, 3 The Ohio State University, Columbus, OH, USA, 4 Yerkes National Primate Research Center, Atlanta, GA, USA, 5 University of Louisiana at Lafayette, Lafayette, LA, USA Background: Despite antiretroviral treatment (ART), individuals living with HIV maintain a higher cardiovascular risk than healthy populations, including an increased prevalence of atherosclerosis. Recently, we have shown that aortas

Poster Abstracts

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CROI 2018