CROI 2025 Abstract eBook

Abstract eBook

Poster Abstracts

NADCs + or between HIV + NADCs + and HIV + NADCs - included different miRNAs and proteins involved in the promotion and progression of cancer (i.e. hsa-miR 1298-5p, hsa-miR-135b-5p, glutathione peroxidase, retinol-binding protein, collagen alpha-1 chain, dermcidin). Conclusions: Our results show the existence of a specific exosomes cargo associated to concomitant HIV infection and NADCs characterized by increased levels of pro-oncogenic and decreased levels of anti-oncogenic proteins and miRNAs. These results show the existence of a relevant role of HIV infection in the promotion and progression of cancer. HIV-Encoded Proteins Induce Pulmonary Arterial Hypertension via Increases in Podocan-Like Protein 1 Laszlo Kovacs 1 , Taylor C. Kress 2 , Rodger MacArthur 2 , Coleton Jordan 2 , Simone Kennard 2 , Eric J. Belin de Chantemele 2 1 Augusta University, Augusta, GA, USA, 2 Medical College of Georgia, Augusta, GA, USA Background: Thanks to the advent of combination antiretroviral therapy (cART), life expectancy has dramatically increased in people with HIV (PWH), and the spectrum of diseases related to HIV has shifted towards non infectious chronic illnesses, including cardiopulmonary disorders. Pulmonary arterial hypertension (PAH) is amongst the most devastating cardiovascular complications of HIV. Pulmonary artery smooth muscle cells (PASMCs) are primary cell types that contribute to the remodeling of pulmonary vascular walls, a critical structural alteration and pathological feature for PAH. However, the etiopathology of pulmonary vascular remodeling has yet to be determined. Methods: Three mouse models of HIV and in vitro experimental studies were used to test whether HIV-derived proteins, which remain in circulation despite cART and well-controlled viremia, contribute to the development of PAH and identify the signaling pathways involved in PAH associated with HIV infection. Results: The expression of HIV proteins in HIV-1 Tg26 mice promoted PAH in male and female mice with no sex differences. These cardiopulmonary alterations were also exacerbated with aging. Remarkably, bone marrow transplant (BMT) from Tg26 to wild-type (WT) mice fully recapitulated the cardiopulmonary phenotype of Tg26 mice, which supports a role for viral proteins derived from hematopoietic cells in PAH. RNA Sequencing identified a novel marker of PAH, Podocan-like protein 1 (Podnl1), whose levels are increased in both intact and BMT Tg26 mice lungs but, more importantly, in the lungs of PWH on cART. Overexpression of Podnl1 in PASMCs increased the levels of collagen-I and PCNA, markers of fibrosis and cell proliferation, respectively. Remarkably, HIV-Tat is the only viral protein detectable in peripheral blood mononuclear cells (PBMCs) obtained from PWH on cART and chronic treatment of mice with Tat reproduced the cardiopulmonary complications of intact and BMT Tg26 mice. In addition, treatment of PASMCs with HIV-Tat and exposure of discarded human pulmonary artery specimens to HIV-Tat elevated the Podnl1 expression. Conclusions: Together, our data identify HIV-Tat and Podnl1 as major contributors to pulmonary vascular remodeling related to HIV infection and provide potential new therapeutic avenues for the prevention of HIV-associated cardiopulmonary complications. Compromised Intestinal Barrier Resilience to Cytokine Disruption Causing Leakage in People With HIV Maliha W. Shaikh 1 , Shalini Singh 2 , Leila B. Giron 2 , Lijuan Zhang 1 , Shivanjali Shankaran 1 , Phillip A. Engen 1 , Michelle Villanueva 1 , Alan Landay 3 , Ali Keshavarzian 1 , Mohamed Abdel-Mohsen 2 1 Rush University, Chicago, IL, USA, 2 Northwestern University, Chicago, IL, USA, 3 University of Texas Medical Branch, Galveston, TX, USA Background: People with HIV (PWH) experience compromised intestinal barrier integrity (gut leakage), which persists despite viral suppression by antiretroviral therapy (ART) and contributes to chronic inflammation. The mechanisms behind this ongoing disruption remain unclear and are likely multifactorial. We tested a novel hypothesis that living with HIV impairs the intestinal barrier’s ability to resist injurious agents, making it more susceptible to leakage when exposed to disruptors such as inflammatory cytokines, which are commonly elevated in PWH. Methods: We generated 3D intestinal apical out organoids from the colon (colonoids) and ileum (enteroids) of 13 PWH on ART (<40 HIV copies/ml plasma) and 19 controls without HIV. Organoids were treated with or without a 3 ng/ mL IFNγ/TNFα cocktail for 3 hours. Organoid permeability was assessed using the 4kDa FITC-dextran diffusion assay, where higher fluorescence indicates

increased permeability. RNA sequencing of baseline (pre-treatment) organoids was performed to identify molecular pathways involved in intestinal leakage. Results: Colonoids, but not enteroids, from PWH on ART showed a non significant trend toward higher baseline permeability compared to controls (p=0.077). However, both colonoids and enteroids from PWH exhibited significantly lower resilience to cytokine stimulation, with increased dextran diffusion compared to controls (p=0.041 for colonoids (Fig), p=0.006 for enteroids). Pathway analysis at baseline revealed disrupted epithelial integrity pathways in PWH organoids, including epithelial-mesenchymal transition (FDR=0.016) and DNA repair (FDR=0.0003). Downregulation of key genes within these protective pathways, such as P3H1 and POLD1, significantly correlated with increased permeability (P3H1: p=0.003, rho =-0.53; POLD1: p=0.02, rho =-0.47). PWH organoids also showed upregulation of pathways detrimental to intestinal barrier, such as oxidative stress-related pathways, including oxidative phosphorylation (FDR=0.03), reactive oxygen species pathway (FDR=0.00002), and fatty acid metabolism (FDR=0.0006). Conclusions: Even with comparable baseline intestinal permeability, intestines of PWH on ART exhibit less resilience to disruption by inflammatory cytokines than those of controls, likely contributing to the ongoing intestinal dysfunction in PWH. Disruption of specific intestinal molecular pathways may contribute to this phenomenon, highlighting potential targets for novel strategies to prevent inflammation-associated comorbidities in PWH.

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Poster Abstracts

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Acute HIV-1 Infection Triggers Myelopoiesis Suppression and Pancytopenia Through IFN-γ Signaling Shuai Gao, Liang Shan Washington University, St Louis, MO, USA Background: HIV-1 infection commonly causes multiple hematopoietic abnormalities, known as pancytopenia, including lymphopenia, anemia, granulocytopenia, and thrombocytopenia, suggesting a central deficiency in bone marrow hematopoiesis. However, the mechanism by which HIV-1 infection leads to bone marrow hematopoietic defects remains unknown due to the lack of appropriate in vivo models. In this study, we established a humanized mouse model that successfully recapitulates the bone marrow cytopenia observed in people living with HIV (PLWH). Methods: Newborn mice were transplanted with human cord blood-derived CD34 + cells. Mice were infected with HIV-1 9-10 weeks post-transplantation when sufficient levels of human CD45 + (huCD45 + ) cells were confirmed. Different R5-tropic strains (HIV BaL , HIV YU2 , HIV JR-CSF , and transmitted virus HIV Rejo ) were utilized for HIV-1 infection. The changes of hematopoietic stem and progenitor cells (HSPCs) in the bone marrow were analyzed using flow cytometry, RNA-seq, and scRNA-seq e.t.c . Results: Post 3-4 weeks of infection, HIV-1 infected mice showed a dramatic reduction in both the percentage and count of huCD45 + , CD34 + , and Lin - CD34 + cells in the bone marrow compared to uninfected controls. ScRNA-seq analysis of bone marrow CD34 + cells revealed that both lymphoid and myeloid progenitors were reduced, and myeloid progenitors had a more significant decrease. Using colony-forming unit assay and secondary transplantation, we demonstrated that bone marrow hematopoietic stem cells isolated from HIV-1 infected mice had reduced stemness and differentiation potency compared to uninfected controls. Since increased response to the IFNγ signaling was observed in myeloid progenitor cells via RNA-seq and scRNA-seq, we generated IFNγ receptor knocked out humanized mice. In these mice, hematopoietic suppression by HIV-1 infection was rescued, further supporting the role of IFNγ in HSPC suppression. Additionally, we identified activated CD8 + T cells

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CROI 2025