CROI 2025 Abstract eBook

Abstract eBook

Poster Abstracts

evaluate the evolution of adipose tissue (AT) between baseline and W48 in PWH with INSTI-associated weight gain switched to TDF/3TC/DOR. We present here preliminary adipocyte gene expression results. Methods: PWH underwent two surgical AT biopsies from subcutaneous fat in the central abdominal area at inclusion and W48 following switch to TDF/3TC/ DOR. AT samples were homogenized using a TissueLyser and RNA was isolated using the Macherey-Nagel method. 14 pairs of samples had a quality level that allowed mRNA quantification by RT-PCR. We evaluated the expression of 14 genes by RT-PCR in comparison with the expression of two reference genes (HPRT and PPIA). Results: Of the 22 enrolled participants, 14 pairs of samples had a quality level that allowed mRNA quantification by RT-PCR. In these 14 PWH (median age: 46 years (IQR 42-57), FTM ratio: 3/11, median BMI: 30.4 kg/m 2 (29.3-35.3) at baseline), weight was significantly reduced by 2.0 kg from 100.6 ± 4.1 to 98.6 ± 4.0 kg (p=0.03) after W48 corresponding to corresponding to a weight loss of 2.3 ± 1%. At inclusion, as expected, the expression of the two genes involved in lipid accumulation, FASN , encoding the lipid storing enzyme fatty acid synthase, and SREBF1C, encoding the transcription factor Srebp-1c, were related (R=0.729, p=0.003). As well, the expression of ADIPOQ , encoding adiponectin, was related to that of PPARG encoding the adipogenic transcription factor PPAR-gamma (R=0.790, p=0.0008), as expected since ADIPOQ transcription is activated by PPAR-gamma. After 48-week on TDF/3TC/DOR, we observed a reduction in the expression of PPARG (1.42 ± 0.11 to 1.23 ± 0.13 p=0.02) and of the two genes involved into lipid accumulation ( SREBF1C 1.41 ± 0.18 to 1.03 ± 0.15 p=0.049 and FASN 1.36 ± 0.18 to 1.02 ± 0.14p=0.085). This suggests reduced adipocyte hypertrophy and lipid accumulation whereas the expression of genes involved in fibrosis, adipokines (leptin adiponectin) and macrophage infiltration was not modified. Conclusions: These results suggest that switch from INSTI to TDF/3TC/ DOR allowed a partial reversal of the INSTI-induced gene expression profile associated with adipocyte hypertrophy and lipid accumulation. Larger clinical pathogenesis studies are needed to better understand the underlying mechanisms of INSTI-induced weight gain and its reversibility by doravirine. In Vitro Modulation of Adipocyte Differentiation by TAF/TDF After Challenge With New ARV Regimens Maria Aurora Carleo 1 , Paolo Maggi 2 , Emiliano Del Genio 2 , Alfonso Baldi 2 , Antonio De Luca 2 , Vincenzo Esposito 1 1 AORN dei Colli Ospedale Cotugno, Naples, Italy, 2 University of Campania Luigi Vanvitelli, Naples, Italy Background: We previously demonstrated in a 3T3L1cells in vitro model of adipogenesis, that Integrase Strand Transfer Inhibitors (INSTI) increase adipogenesis, while, tenofovir alafenamide fumarate (TAF) and tenofovir disoproxil fumarate (TDF), displayed an inhibitory effect, counteracting increased adipogenesis caused by INSTIs [dolutegravir (DTG), bictegravir (BIC)]. Deregulation of the expression levels of two families of adipocyte differentiation transcription factors, the CCAAT/enhancer-binding proteins (C/ EBPs) and the peroxisome proliferator-activated receptors (PPARs), was also confirmed with a different degree of expression according to different antiviral drug. Morphological changes were also detected in cells treated by TDF/TAF with increased expression of E-TR7 a well-known fibroblastic marker. Presently it is not clear the effect of nucleoside reverse transcriptase inhibitors (NNRTIs), alone or in combination with TDF/TAF or INSTIs on adipocyte differentiation. Aim of the study was to evaluate in vitro these last potential activities as in routine clinical practice. Methods: We used a 3T3-L1 cells in vitro model of adipogenesis to study the effects on adipocyte differentiation of the NNRTIs doravirine (DOR) and rilpivirine (RPV), alone or in combination with the previously evaluated DTG and the newer INSTI cabotegravir (CAB), or TDF or TAF. Expression levels of PPARγ and C/EBPα, and the intracellular lipid accumulation by Red Oil staining, were used to monitor adipocyte differentiation (fig. 1). Immunoistochemistry for E-TR7 was also performed on terminally differentiated cells. Results: CAB, DOR and RPV were all able to increase adipogenesis, compared to control, while cells showed some morphological changes. This last effect was more evident with CAB and DOR, and less with RPV. When used in combination, NNRTIs were able to increase the adipogenic effects of CAB and DTG, while TAF and TDF respectively combined with RPV and DOR displayed an inhibitory effect. Furthermore, NNRTIs and CAB enhanced the expression levels of ER-TR7

compared to control, being the combination DTG+DOR less effective in this activity. Conclusions: Our data support the evidence that in-vitro challenge of 3T3-L1 cells with INSTIs and NNRTIs is able to increase adipocytic differentiation and to drive a number of these cells toward the expression of fibroblastic features, whereas TAF and TDF when combined to different ARV have an antagonistic role on this phenomenon confirming our previous report.

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HIV-Induced Immunomodulation and Cardiometabolic Disease Development in Mice on High-Fat Diets Victoria R. Stephens 1 , Laventa Obare 1 , Xiuqi Zhang 1 , Kisyua Nthenge 1 , Eseoghene Ogaga 1 , Joshua Simmons 1 , Mona Mashayekhi 1 , Antentor Hinton Jr 2 , David Harrison 2 , Annet Kirabo 1 , Celestine Wanjalla 1 1 Vanderbilt University Medical Center, Nashville, TN, USA, 2 Vanderbilt University, Nashville, TN, USA Background: The development of therapies to treat people living with HIV (PLWH) has significantly increased their life expectancy, nearing that of people without HIV (PWoH). ART leads to aviremia; however, chronic inflammation persists, increasing the risk of comorbidities such as cardiometabolic diseases. Our understanding of how HIV-related inflammation leads to cardiometabolic disease is associative without precise mechanisms. We hypothesize that subsets of immune cells in peripheral blood mononuclear cells (PBMCs) are involved in the pathways leading to HIV-associated cardiovascular disease. Methods: To interrogate this hypothesis, we reconstituted the immune system of immune deficient (NSG) mice also lacking MHC I and II with PBMCs from patients with or without HIV. Recipient mice were placed on either a standard chow diet (LFD/SCD) or a high-fat diet (HFD) and then assessed for weight gain, metabolism using a glucose tolerance test and metabolic cages, and immune cell composition changes by flow cytometry. Results: By day 30, mice with HIV on a high-fat diet (HFD-PLWH) experienced an 11.5-fold increase in weight compared to a 5.7-fold increase in non-HIV mice on the same diet (HFD-PWoH). By day 114, the rate of weight gain in both groups was comparable. Glucose tolerance tests revealed that mean plasma insulin levels after 10 minutes were notably higher in HFD mice (3.2ng/ml in HFD-PLWH and 2.4ng/ml in HFD-PWoH), compared to those on a SCD (0.3ng/ml LFD-PLWH and 0.1ng/ml LFD-PWoH), indicative of metabolic syndrome in the high-fat diet mice. Interestingly, we observed a strong correlation between the proportion of CGC + CD4 + T cells in PBMCs and weight gain in HFD-PLWH mice (r=0.78, p=0.05). This correlation was not observed in the LFD-PLWH group (r=0.28, p=0.57). Similarly, no such correlation was seen in HFD-PWoH (r=0.21, p=0.66) or LFD-PWoH groups (r=0.17, p=0.76). At the end of the experiment (day 120), we examined immune cells in various organs, including the spleen, liver, kidney, and intestines. Findings revealed significantly more human CD3 + PD1 + CD57 +/- CX3CR1 + CD4 + T cells in HFD-PLWH mice compared to CD3 + PD1 + CD57 - CX3CR1 - CD4 + T cells in HFD-PWoH mice. Conclusions: HFD-PLWH had the worst metabolic outcomes by all measures, implicating a causal role in immune cell changes in metabolic outcomes. Collectively, these data suggest that HIV, in concert with a HFD, mediates immunomodulatory effects that promote the development of phenotypes indicative of cardiometabolic disease in mice.

Poster Abstracts

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CROI 2025 280