CROI 2019 Abstract eBook

Abstract eBook

Poster Abstracts

Conclusion: Single housing of SIV-infected macaques may provide an exogenous cause of immune modulation and introduce increased variability in data, with the potential to confound results, reduce the translational value of the model and interfere with reproducibility. 213 ORAL CYTOKINE EXPRESSION IS LINKED TO ORAL HIV-1 LEVELS IN ACTG A5254 Joseph Rocco 1 , Zachary York 2 , Janet McLaughlin 1 , Luann Borowski 1 , Jennifer Webster-Cyriaque 3 , Caroline H. Shiboski 4 , Judith Aberg 5 , Charles Rinaldo 1 , Bernard J. Macatangay 1 1 University of Pittsburgh, Pittsburgh, PA, USA, 2 University of Wisconsin–Madison, Madison, WI, USA, 3 University of North Carolina at Chapel Hill, Chapel Hill, NC, USA, 4 University of California San Francisco, San Francisco, CA, USA, 5 Icahn School of Medicine at Mt Sinai, New York, NY, USA Background: HIV infection is known to disrupt oral mucosal immunity, but the pathogenesis of this immune dysregulation remains unknown. We determined the levels of 11 soluble immune mediators in oral washings of people with HIV (PWH) with varying levels of plasma viremia and CD4+ T cell counts. We also evaluated whether these immune mediators are associated with levels of HIV in blood and oral washings with the aim of characterizing the mucosal immune response at variable stages of HIV infection. Methods: Oral washings were obtained from participants of ACTG A5254, a cross-sectional study of PWH to evaluate oral complications of HIV. Participants were divided into 4 strata: A (n=148; 52% on ART), CD4≤200 cells/mm3, plasma HIV-1 RNA (VL)>1000 cps/mL; B (n=82; 98% on ART), CD4≤200, VL≤1,000; C (n=29; 21% on ART), CD4>200, VL>1000; D (n=29; 100% on ART), CD4>200, VL≤1000. Levels of soluble markers were tested in oral washings using a multi- bead fluorescent platform, and were compared between strata. Associations between soluble marker levels and HIV in plasma and oral washings as well as CD4+ counts were determined. Results: Stratum (St) A participants (CD4 <200, VL >1000) had higher levels of pro-inflammatory markers IL-6, IL-17, TNFα, IL-1β, and IFNγ compared to St B and St D which had VL<1000 and where 98-100% of participants were on ART (p=0.02 to p<0.0001; Kruskal-Wallis with Dunn’s post-test, adjusted for multiple comparisons), but were not different from St C. Two pro-inflammatory markers, IL-12p70 and IL-8, and the anti-inflammatory marker IL-10 differentiated St A from the other 3 strata (p=0.046 to p<0.0001). St B and D had no differences in levels of the soluble markers except for IFNγ (p=0.04). Oral HIV levels correlated with plasma HIV (r=0.76; p<0.0001, Spearman) and with IL-6, IL-1β, IL-8, TNFα, IFNγ, and IL-10 (all r>0.4; p<0.001). Meanwhile, plasma VL only correlated with TNFα, IFNγ, and IL-10 (all r>0.4; p<0.001). No correlations were seen with IL-2, and only modest (r<0.35) correlations were seen with IL-17. No significant correlations were observed with CD4 count. Conclusion: Our results suggest that high levels of oral HIV rather than low CD4 counts or plasma HIV are more linked to production of oral immune mediators. Despite severe immunosuppression, participants with AIDS demonstrated elevated levels of cytokines corresponding to both Th1 and Th2 T cell responses. The interplay of HIV and these immune mediators could be an important factor in the oral health of PWH. 214 HIV INFECTION AND SMOKING DEFERENTIALLY REGULATE ALVEOLAR MACROPHAGES Charles P. Neff , Thomas Campbell, Andrew Fontenot, Brent E. Palmer University of Colorado Anschutz Medical Campus, Aurora, CO, USA Background: HIV infection impacts immune cells in the lung leading to pulmonary complications which persist with antiretroviral therapy (ART). Alveolar macrophages (AM) are principle immune cells type in bronchoalveolar compartment and as such play a pivotal role in host defense against pathogenic microorganisms and tissue remodeling. Examination of the effect of HIV on AM is complicated by the high prevalence of smoking in HIV infected subjects from the United States. Smoking increases auto-fluorescence of AMs, inhibiting the reliability and resolution of traditional flow cytometry. Cytometry by Time of Flight (CyTOF) utilizes pure metal conjugated antibodies and detection by mass cytometry, which effectively bypasses auto-fluorescence. Here, we utilize CyTOF to comprehensively evaluate the effect of HIV infection and smoking on AM. Methods: Bronchoalveolar lavage (BAL) cells from 10 untreated HIV-infected non-smokers, 9 untreated HIV-infected smokers, 10 HIV-seronegative non-smokers and 9-HIV-seronegative smokers was subjected to traditional flow cytometry and CyTOF. Our CyTOF panel consisted of 34 unique markers

and phenotypic analysis was performed using traditional methods and three unbiased clustering algorithms. Results: Compared to those without HIV we found a decrease in CD206 (p=0.0002), CD71 (p=0.03) and CD164 (p=0.002) positive cells, indicating a loss of alternatively activated AMs (M2) caused by HIV infection. The loss of M2 macrophages indicates an increased inflammatory environment. Smoking increased AM expression of CCR2 (p=0.007) which is a marker of inflammatory macrophages. Together, compared to healthy non-smokers, smoking and HIV increased CXCR4 expression on AM (p=0.004) demonstrating increased susceptibility to X4 tropic HIV infection. Conclusion: While the aim of characterizing alveolar macrophages during HIV infection and smoking was our primary goal, this study also demonstrates the sensitivity of mass cytometry, and its ability to detect significant differences between patient groups which would have otherwise been masked by auto-fluorescence. Overall, these findings indicate that HIV and smoking drive alveolar macrophages toward an inflammatory state, leading to an overall more inflammatory environment in the lung. 215 HUMAN INFECTION WITH ZOONOTIC SIMIAN FOAMY VIRUSES: ALTERED CD4 AND CD8 T LYMPHOCYTES Antoine Gessain 1 , Thomas Montange 1 , Edouard Betsem 2 , Chanceline Bilounga Ndongo 3 , Richard Njouom 4 , Florence Buseyne 1 Background: A spillover of simian foamy virus (SFV) to humans, following bites from infected nonhuman primates (NHPs), is ongoing in exposed populations. These retroviruses establish persistent infections of unknown physiological consequences to the human host. Replication-competent virus can be isolated from human blood cells, and SFV DNA has been detected in blood lymphocytes. Human infection with zoonotic SFV is thus a natural model to study the key steps of the emergence of retroviruses. Here, we aimed to assess whether SFV infection is associated with changes in the phenotype of peripheral blood mononuclear cells (PBMCs). Methods: We performed a case-control study to compare 15 Cameroonian hunters infected with gorilla SFV and 15 controls matched for age and ethnicity. All participants were men and had been injured by a NHP. Ages ranged from 22 to 75 years. SFV infection was defined by positive results for both western blots and polymerase chain reaction assays. The duration of SFV infection ranged from 1 to 45 years. CD4 and CD8 T lymphocytes, B and NK lymphocytes, and their major subsets were quantified by flow cytometry. Wilcoxon signed-rank tests were used to compare cases and controls. Results: The cases had significantly higher percentages of CD8 T lymphocytes and lower CD4/CD8 ratios than controls (median: 17.6% vs. 13.7%, P = 0.03 and 3.1 vs. 3.5, P = 0.04, respectively). The percentage of CD4 T lymphocytes were similar for cases and controls (47.7% vs. 46.9%, P = 0.73). Programmed cell death 1 (PD-1) expression on memory CD4 T lymphocytes was higher for cases than controls (31.7% vs. 24.7%, P = 0.001). B and NK lymphocytes showed no differences between cases and controls (8.7% vs. 9.9%, P = 0.70 and 7.5% vs. 6.0%, P = 0.78, respectively). Conclusion: This case-control study of apparently healthy SFV-infected Cameroonian hunters showed phenotypic differences among blood T lymphocytes. Lymphocyte subsets affected in chronic untreated HIV infection were also affected in chronic SFV infection, albeit to a lower extent. The decreased CD4/CD8 ratio and increased expression of the exhaustion marker PD-1 are consistent with a T-cell response against viral infection. Although SFV has been reported to be nonpathogenic, our findings of T-lymphocyte activation may have implications for infected individuals. 216 CHARACTERIZATION OF PLASMA METABOLITE PROFILE IN HIV+ PERSONS WITH OR WITHOUT IRIS Luxin Pei 1 , Kiyoshi Fukutani 2 , Brian Ingram 3 , John Luster 3 , Andrea Lisco 1 , Maura Manion 1 , Elizabeth Laidlaw 1 , Bruno Andrade 2 , Irini Sereti 1 1 National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA, 2 Instituto Gonçalo Moniz, Salvador, Brazil, 3 Metabolon, Inc, Morrisville, NC, USA Background: Immune reconstitution inflammatory syndrome (IRIS) is an aberrant inflammatory response against an underlying infection after initiation of antiretroviral therapy (ART) in HIV+ persons and is associated with significant morbidity and mortality. Inflammation and T cell activation are dependent 1 Institut Pasteur, Paris, France, 2 University of Yaoundé, Yaoundé, Cameroon, 3 Ministère de la Santé Publique du Cameroun, Yaoundé, Cameroon, 4 Centre Pasteur du Cameroun, Yaoundé, Cameroon

Poster Abstracts

76

CROI 2019