CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

Conclusion: We showed that genetic variants associated to HIV control are associated to plasma and gene expression levels of NK cell receptors, their ligands MICA/MICB and HLA-C, and effector molecule granzyme A. This suggests that these variants might contribute to HIV control by modulating NK cell function. The association of variants in the MHC locus with immune responses against CMV hints to a shared genetic basis of immune responses against HIV and CMV. Finally, we showed that our QTL mapping studies are valuable resources that can aid understanding how genetics contributes to disease outcome in PLHIV. The figure, table, or graphic for this abstract has been removed. Plasma Proteome Signature of Immune Inhibition Is Associated With CMV Coinfection in People With HIV Michael L Freeman 1 , Gordon Honerkamp Smith 2 , Patricia K. Riggs 2 , Scott L. Letendre 2 , Peter W. Hunt 3 , Sara Gianella Weibel 2 1 Case Western Reserve University, Cleveland, OH, USA, 2 University of California San Diego, La Jolla, CA, USA, 3 University of California San Francisco, San Francisco, CA, USA Background: Cytomegalovirus (CMV) coinfection is highly prevalent and is associated with persistent inflammation in people with HIV (PWH). A comprehensive analysis of the plasma proteome in PWH with or without CMV has never been performed previously. Identifying proteomic signatures of CMV infection in PWH will improve understanding of CMV-associated comorbidities in PWH and may lead to the development of novel therapeutics. Methods: The Olink Proteomics proximity extension assay was used to characterize the plasma proteome from age- and CD4 count-matched PWH with (CMV+, N=30, 23.3% female) or without (CMV-, N=19, 10.5% female) CMV coinfection on suppressive antiretroviral therapy (ART). Resulting normalized protein expression (NPX) values were analyzed using a linear mixed effects model to determine protein expression differences between groups; P-values were adjusted using the Benjamini-Hochberg method. Partial least squares- discriminant analysis (PLS-DA) was used to discriminate between CMV groups using the NPX values as input features. To measure the predictive power of the PLS-DA model, we used five-fold cross-validation with 100 repeats to estimate the generalization error in terms of accuracy and area under the receiver operating characteristic (ROC) curve (AUC). Results: We found that 117 of 368 (31.8%) proteins were differentially expressed (P<0.05) after adjustment for multiple comparisons. Proteins most significantly upregulated in CMV+ participants were associated with inhibition of the immune response (e.g., FCRL6, HLA-DRA, KLRD1, CD70, LY9, SLAMF7) or inflammation (e.g., CXCL9, CXCL10). Several of the most significantly downregulated proteins in CMV+ PWH were associated with apoptosis (e.g., CASP2, TRIM21, TRAF2). Using our PLS-DA model, we were able to predict CMV serostatus with a cross-validated accuracy of 80.8% and AUC of 87.8%. Conclusion: CMV serostatus substantially influences protein expression with nearly a third of proteins differentially expressed. Our data demonstrate that CMV is a major contributor to the plasma proteome in PWH and suggest that targeting CMV in PWH may be a viable strategy for therapeutic interventions. While the cross- sectional design limits causal inference, the increase in immune inhibitory elements and the reduction of pro- apoptotic molecules in CMV+ PWH suggest that CMV may facilitate the maintenance of the latent HIV reservoir in PWH on suppressive ART.

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B-Cells Augment HIV-1 Expression in Secondary Lymphoid Tissues Matthew Ollerton 1 , Joy Folkvord 1 , Cecilia Shikuma 2 , Fredrick Yost 2 , David Parry 1 , Magali Porrachia 3 , Davey M. Smith 3 , Sara Gianella Weibel 3 , Elizabeth Connick 1 1 University of Arizona, Tucson, AZ, USA, 2 University of Hawaii, Honolulu, HI, USA, 3 University of California San Diego, San Diego, CA, USA Background: HIV-expressing (vRNA+) cells are consistently found in secondary lymphoid tissues (SLT) of people with HIV (PWH) on antiretroviral therapy (ART) and likely drive viral rebound upon ART cessation. Little is known about what affects HIV expression in SLT. We hypothesized that B cells promote HIV expression. Methods: Disaggregated tonsil cells from persons without HIV were depleted of CD19+ cells by magnetic beads. CD19- cells were spinoculated with X4 or R5-tropic HIV GFP reporter virus, cultured 3 days with dye- labeled CD19+ or CD19- cells and saquinavir, and %GFP+ of unlabeled CD3+CD8- cells and GFP median fluorescence intensity (MFI) determined by flow cytometry. Tonsil cells were also sorted into CD4+ T follicular helper (TFH; CD3+CD8-CXCR5hiPD-1hi), nonTFH (CD3+CD8-CXCR5+/-PD-1+/-), memory B (IgD-CD38-), pre-germinal center B (pre-GCB; IgD+CD38+), GCB (IgD-CD38+), and naïve B (IgD+CD38-). TFH and nonTFH were infected with X4 HIV, incubated with B cell subsets or control CD4+ T cells, and %GFP+ and GFP MFI determined. Sections of inguinal lymph node (LN) from 6 male PWH on ART for 7-29 years and spleen from 6 male PWH on ART for >5 years were analyzed by in situ hybridization for vRNA and immunofluorescent antibody staining for CD20 to determine follicular (F) regions. Frequencies of vRNA+ cells in F and extrafollicular (EF) regions, EF B cells, and EF B cells adjacent to vRNA+ cells were determined by visual inspection and quantitative image analysis. Data reported are medians. Nonparametric statistical tests were used. Results: CD19 depletion reduced %GFP+ and GFP MFI by 32% and 30% in X4 (n=7; p=0.02 and 0.03) and 37% and 29% in R5-HIV infected cells (n=7; both p=0.02) compared to cultures with CD19+ cells. Memory, pre-GCB, GCB, and to a lesser extent naïve B cells elevated HIV expression in both nonTFH (%GFP+ p<0.05; GFP MFI p<0.05; n=6) and TFH (%GFP+ increased by all B cell subsets except naive, p<0.05; n=6; all B cell subsets augmented GFP MFI, p<0.05; n=6). Frequencies of vRNA+ cells were higher in B cell-rich F than EF regions in LN (0.28 vs 0.17 cells/mm 2 ; p=0.03) and spleen (0.07 vs 0.05 cells/mm 2 ; p=ns). In EF areas, vRNA+ cells were adjacent to B cells more often than predicted by chance in all four LN (3.1-fold; range, 3-5.2) and four spleens (1.4-fold, range 1.1-2) evaluated. Conclusion: B cells upregulate HIV expression in SLT CD4+ T cells and are associated with vRNA+ cells in SLT of PWH on ART. Mechanisms by which B cells augment HIV expression merit investigation. Herpesviruses Reactivation and Associated Systemic Inflammation During Initiating ART, Rakai-Uganda Victor Ssempijja 1 , Viviane Callier 1 , Martha Nason 2 , Aggrey Anok 3 , Andrea Lisco 2 , Andrew Redd 2 , Thomas C. Quinn 2 , Adam Rupert 1 , Stephen Tomusange 3 , Taddeo Kityamuweesi 3 , Paul Bbuule 3 , Irini Sereti 4 , Steven J. Reynolds 2 1 Leidos Biomedical Research, Inc, Frederick, MD, USA, 2 National Institutes of Health, Bethesda, MD, USA, 3 Rakai Health Sciences Program, Kalisizo, Uganda, 4 National Institutes of Health, Frederick, MD, USA Background: We conducted a prospective observational study to evaluate HSV-2, Cytomegalovirus (CMV), and HHV-8 herpesviruses shedding after ART initiation and associated markers of systemic inflammation in women living with HIV (WLWH). Methods: We recruited 187 WLWH not on ART, aged ≥18 years from three HIV/ ART clinics in south-central Uganda. CMV and HSV-2 shedding was quantified by PCR on vaginal secretions and HHV-8`s shedding on oral swabs. McNemar's test was used to evaluate changes in shedding of HSV-2, CMV and HHV-8 pre-ART (study baseline visit) and after ART initiation (weeks 4 and 8). Logistic regression models were used to evaluate associations of markers of systemic inflammation (plasma levels of IL-6, CRP, TNFα or sCD14) with viral- shedding at similar time points. We conducted a stratified analysis by pre-ART CD4 counts (≤200 cells/µl versus >200 cells/µl). Results: 187 out of 196 (95%) screened women were eligible with a mean age 30.1 years and enrolled at ART initiation. 25.9% of participants had a pre-ART CD4 count less than 200 cells/µl. Follow-up occurred for 91% and 87% of participants at weeks 4 and 8 post-ART initiation, respectively. During the study, 69.1% of participants shed CMV, 44.1% shed HSV-2, and 30.1% shed HHV-8.

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Poster Abstracts

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CROI 2024