Whether antiretroviral therapy (ART) is always completely suppressive, or HIV might continue to replicate at low levels despite ART in some people with HIV (PWH), is still debated. Here, we intensified the ART regimen by doubling dolutegravir (DTG) dosage and investigated the impact of this strategy on HIV blood and tissue reservoirs, immune activation, and inflammation. Twenty HIV-infected adults, who had received a triple ART consisting of 50 mg DTG/600 mg abacavir/300 mg lamivudine pre-intensification and had been suppressed on ART for at least 2 years, were enrolled in a phase 2 randomized clinical trial (https://clinicaltrials.gov/ identifier: NCT05351684). Half of them received an additional 50 mg of DTG for a period of 84 days. As expected, plasma and tissue DTG concentrations significantly increased during the study period in the intensified group but not in the control group. Accordingly, significant decreases in total HIV DNA, intact HIV DNA, and cell-associated unspliced (US) HIV RNA in peripheral blood mononuclear cells, as well as in the US RNA/total DNA ratio, were observed in the intensified group but not in the control group. Intensification also modestly reduced markers of immune activation and exhaustion but had no measurable impact on systemic or tissue inflammation. Together with this, intensification resulted in a temporary decrease in the CD4/CD8 ratio that returned to baseline by day 84. Our results strongly suggest that the pre-intensification ART regimen was not completely suppressive. If confirmed in larger clinical trials, these results could have an impact on the clinical management of PWH and HIV curative strategies.
© 2025, Fombellida-Lopez et al.

Liver metastases are relatively resistant to checkpoint blockade immunotherapy. The hepatic tissue has distinctive features including high numbers of NK cells. It was therefore important to conduct in-depth single-cell analysis of NK cells in colorectal cancer liver metastases (CRLMs) with an effort to dissect their diversity and to identify candidate therapeutic targets. By combining unbiased single-cell transcriptomic with multiparametric flow cytometry analysis, we identified an abundant family of intrahepatic CD56bright NK cells in CRLMs endowed with antitumor functions resulting from specific transcriptional liver programs. Intrahepatic CD56bright and CD56dim NK lymphocytes expressed unique transcription factors (IRF8, TOX2), a high level of chemokines, and targetable immune checkpoints, including CXCR4 and the IL-1 receptor family member IL-1R8. CXCR4 pharmacological blocking and an anti-IL-1R8 mAb enhanced the effector function of CRLM NK cells. Targeting the diversity of liver NK cells and their distinct immune checkpoint repertoires is key to optimize the current immune therapy protocols in CRLM.

Mycobacterium tuberculosis (Mtb), the most common co-infection among people living with HIV (PLWH), aggravates the associated morbidity and mortality in these individuals; however, the immune-modulatory role of Mtb in the pathogenesis of HIV infection remains incompletely understood.
We investigated the role of Mtb infection in regulating adaptive immune responses with reference to the expression of five immune checkpoint molecules (ICMs) in co-infected individuals in a cross-sectional study conducted on treatment-naïve human cohorts from North India, including PLWH, people with Mtb infection, people with HIV-Mtb co-infection, and healthy volunteers as controls.
The data revealed a significantly increased gene expression of TIM-3 (p = 0.0058), LAG-3 (p < 0.0001), PD-1 (p = 0.0090), and CTLA-4 (p = 0.0008). It also revealed a higher frequency of CD4+ and CD8+ T-cells surface-expressing TIM-3+, CTLA-4+, LAG-3+. Finally, it showed cells co-expressing two ICMs together (p < 0.05) in individuals with HIV-Mtb co-infection as compared to HIV mono-infected ones. Interestingly, the frequency of these cells correlated inversely with the absolute CD4+ T-cell count and positively with the plasma viral load (p < 0.05), indicating direct association with HIV disease progression.
These findings suggest that Mtb co-infection exacerbates immune exhaustion in co-infected individuals. Targeting ICMs with pharmacological immune checkpoint inhibitors (ICIs) offers a promising approach for better clinical management of co-infected individuals.

Systemic lupus erythematosus (SLE) has been linked to gut microbiome dysbiosis, notably an overabundance of Streptococcus anginosus; however, the impact of this microbial imbalance on disease pathogenesis remains unclear. Here, we investigated the contribution of S. anginosus-derived extracellular vesicles (SA-EVs) to SLE progression, with an emphasis on lupus nephritis (LN). Fifty-four SLE patients and 43 healthy controls (HC) were recruited. The faecal, blood and serum samples from participants were collected. SLE disease activity (SLEDA) was evaluated by the SLEDA Index (SLEDAI). Stool S. anginosus abundance was quantified by quantitative PCR, NK cell activation by flow cytometry and serum proinflammatory cytokines profile by ELISA. Lupus-prone MRL/lpr mice were orally administered SA-EVs to evaluate in vivo inflammatory responses, renal NK cell activation and renal histopathological changes. S. anginosus levels were significantly elevated in SLE patients relative to HC, positively correlated with SLEDAI scores and NK cell cytotoxicity. In vitro, SA-EVs stimulation of patient NK cells significantly heightened proinflammatory mediator production (granzyme B, TNF-α), increased cytotoxicity and downregulated inhibitory receptors (TIM-3, NKG2A, TIGIT) compared to control EVs from S. Salivarius (SS-EVs). Mechanistically, lipoteichoic acid (LTA) within SA-EVs engaged Toll-like receptor 2 (TLR2) on NK cells, activating MyD88/NF-κB signalling pathway. In MRL/lpr mice, SA-EVs treatment increased renal immune complex deposition, upregulated renal NK cell activation markers (NKp44, NKp46), and exacerbated LN pathology with greater immune cell infiltration and inflammatory cytokine levels. Furthermore, NK cell depletion with anti-NK1.1 antibodies significantly prolonged survival in SA-EVs administered mice. Thus, SA-EVs exacerbate SLE by hyperactivating NK cells via the TLR2-MyD88-NF-κB pathway, leading to amplified systemic inflammation and aggravated LN. These findings underscore the potential of targeting SA-EVs for therapeutic intervention in SLE.
© 2025 The Author(s). Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.

Engineered T cell-based adoptive immunotherapies met promising success for the treatment of hematological malignancies. Nevertheless, major hurdles remain to be overcome regarding the management of relapses and the translation to solid tumor settings. Properties of T cell-based final product should be appropriately controlled to fine-tune the analysis of clinical trial results, to draw relevant conclusions, and finally to improve the efficacy of these immunotherapies. For this purpose, we addressed the existence of atypical T cell subsets and deciphered their phenotypic and functional features in an HPV16-E7 specific and MHC II-restricted transgenic-TCR-engineered T cell setting. To note, atypical T cell subsets include mismatched MHC/co-receptor CD8 or CD4 and miscommitted CD8+ or CD4+ T cells. We generated both mismatched and appropriately matched MHC II-restricted transgenic TCR on CD8 and CD4-expressing T cells, respectively. We established that CD4+ cultured T cells exhibited miscommitted phenotypic cytotoxic pattern and that both interleukin (IL)-2 or IL-7/IL-15 supplementation allowed for the development of this cytotoxic phenotype. Both CD4+ and CD8+ T cell subsets, transduced with HPV16-E7 specific transgenic TCR, demonstrated cytotoxic features after exposure to HPV-16 E7-derived antigen. Ultimately, the presence of such atypical T cells, either mismatched MHC II-restricted TCR/CD8+ T cells or cytotoxic CD4+ T cells, is likely to influence the fate of patient-infused T cell product and would need further investigation.
Copyright © 2024 Mercier-Letondal, Kumar, Marton, Bonnefoy, Fredon, Boullerot, Dehecq, Adotévi, Godet and Galaine.