Efecto de la infección por el VIH-1 sobre el fenotipo y la funcionalidad de las células T reguladoras (Treg): Uso de los dendrímeros carbosilano como protectores de las Treg frente a la infección por el VIH

Tesis doctoral inédita, leída en Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 28/03/2014Regulatory T cells (Treg) are a subpopulation of CD4+ T cells that play a crucial role in establishing and maintaining self-tolerance and immune homeostasis. During an infectious process, Treg cells play a key role modulating host immune responses and thus avoiding over-reactive immunity. This mechanism could be especially important in the case of HIV infection, due to the frequent immune hyperactivation observed in HIV-infected patients. However, there are controversial findings about the role of these cells in HIV infection and the exact role of Treg cells in HIV infection is not clear. In this study, we demonstrated that HIV-1 directly infects Treg cells, down-regulating the Foxp3 expression, which was followed by a reduction in the suppressive capacity, and alterations in the cytokine secretion pattern. The results showed that Foxp3 down-regulation in HIV-infected Treg was related with an increase in the DNMT3b expression, associated with higher methylation of CpG sites in the FOXP3 locus. Other objective of this Memory was to corroborate if this mechanism also occurs in vivo, analysing the Treg population in HIV infected patients. The results indicated that the absolute number of Treg cells was significantly lower in HIV-infected patients, notably in patients with high VL, in comparison with healthy subjects. The deficiency of Treg cells in patients was probably due to the direct effect of HIV on Treg, and also by a desregulation of the IL-2 signaling pathway on these cells. We also confirmed that suppressive function of Treg from HIV-infected patients was impaired, which could contribute to the HIV-mediated hyperactivation. On the other hand, we also investigated the efficacy of carbosilan dendrimers to block or reduce the HIV-infection, and to prevent the effects of infection in the phenotype of Treg. In general, cationic and anionic dendrimers showed high biocompatibility in Treg cells, and dendrimers did not produce important changes in the viability, phenotype or suppressive function of Treg cells. The results also showed that anionic dendrimers 2G-S24P and 2G-S16 have the capacity per se of to inhibit HIV infection in Treg cell, and prevent the effects of HIV infection in the Treg phenotype. The capacity of these dendrimers to protect the Treg against HIV infection could have interesting applications in the therapeutically use of Treg in HIV patients

Combined or Sequential Treatment with Immune Checkpoint Inhibitors and Car-T Cell Therapies for the Management of Haematological Malignancies: A Systematic Review

The aim of this paper was to review the available evidence on the efficacy and safety of combined or sequential use of PD-1/PD-L1 immune checkpoint inhibitors (ICI) and CAR-T cell therapies in relapsed/refractory (R/R) haematological malignancies. A systematic literature review was performed until 21 November 2022. Inclusion criteria: cohort studies/clinical trials aimed at evaluating the efficacy and/or safety of the combination of CAR-T cell therapy with PD-1/PD-L1 inhibitors in R/R haematological malignancies, which had reported results. Those focusing only on ICI or CAR-T separately or evaluating the combination in other non-hematological solid tumours were excluded. We used a specific checklist for quality assessment of the studies, and then we extracted data on efficacy or efficiency and safety. A total of 1867 articles were identified, and 9 articles were finally included (early phase studies, with small samples of patients and acceptable quality). The main pathologies were B-cell acute lymphoblastic leukaemia (B-ALL) and B-cell non-Hodgkin’s lymphoma (B-NHL). The most studied combination was tisagenlecleucel with pembrolizumab. In terms of efficacy, there is great variability: the combination could be a promising option in B-ALL, with modest data, and in B-NHL, although hopeful responses were received, the combination does not appear better than CAR-T cell monotherapy. The safety profile could be considered comparable to that described for CAR-T cell monotherapy

Reducing the drug burden of sedative and anticholinergic medications in older adults: a scoping review of explicit decision criteria

[Objectives] To describe the extent, characteristics, and knowledge gaps regarding explicit decision criteria for deprescribing drugs with anticholinergic or sedative properties (Ach/Sed) in older adults.[Design] Scoping review.[Setting and Participants] Original studies, clinical trial protocols, grey literature, and Summaries of Product Characteristics.[Methods] Searches targeting explicit decision criteria for deprescribing Ach/Sed were performed across MEDLINE, EMBASE, CINAHL, and Web of Science, including trial registries (clinicaltrials.gov, ICTRP, EU-CTR, ANZCTR) for pertinent articles, study protocols. Additionally, to encompass non-traditional or 'grey literature' sources, Google searches and relevant agency websites were explored, alongside the summary of product characteristics for Ach/Sed.[Results] The initial literature search identified 8,192 unique data sources. After review, 188 original articles or books, 79 internet sources, and 127 SmPCs were included. Examining these sources for explicit criteria for 154 Ach/Sed, overall, 1,271 explicit criteria guidance for identifying clinical scenarios warranting deprescription of Ach/Sed across 145/154 Ach/Sed were identified. These criteria were identified mainly from qualitative research and Summaries of Product Characteristics. Additionally, 455 criteria-based recommendations suggesting approaches for tapering implementation across 76/154 Ach/Sed were identified, mostly from sources classified as expert opinions. Significant heterogeneity was found across the approaches for tapering Ach/Sed.[Conclusions] This scoping review provides a comprehensive overview of the literature providing guidance for clinical scenarios where Ach/Sed should be deprescribed and highlights the existing knowledge gaps regarding comprehensive guidance on tapering these drugs which warranties future research and development.Peer reviewe

Nanotechnology as a New Therapeutic Approach to Prevent the HIV-Infection of Treg Cells

<div><p>Background</p><p>HIV-1 has proved to infect regulatory T cells (Treg) modifying their phenotype and impairing their suppressive capacity. As Treg cells are a crucial component in the preservation of the immune homeostasis, we researched that the antiviral capacity of carboxilan dendrimers prevents the HIV-1 infection of Treg and their effects. The phenotype and suppressive capacity of Treg treated or non-treated with carbosilane dendrimers were studied by flow cytometry. Treated and non-treated Treg from healthy donors were infected with HIV-1_NL4.3. The infection of Treg cells by HIV-1, and protective effect of two dendrimers were determined by measuring antigen p24^gag in the supernatant of the culture and intracellular.</p><p>Results</p><p>The Treg cells were treated with cationic and anionic carbosilane dendrimers. The results showed that both dendrimers did not modify the phenotype and functionality of Treg cells compared with non- treated Treg cells. Anionic dendrimers showed high biocompatibility with normal activity of the Treg cells and in antiviral assays. These dendrimers were highly active against HIV-1 preventing the infection of Treg, and were able to protect the Treg from the Foxp3 downregulation induced by the HIV-1 infection.</p><p>Conclusions</p><p>This is the first work showing that the <i>in vitro</i> use of anionic dendrimers prevent the HIV-1 replication and the infection of expanded Treg cells in culture, which raises the possibility to use Treg cells therapeutically in HIV-1-infected subjects.</p></div

Combined or Sequential Treatment with Immune Checkpoint Inhibitors and Car-T Cell Therapies for the Management of Haematological Malignancies: A Systematic Review

© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).The aim of this paper was to review the available evidence on the efficacy and safety of combined or sequential use of PD-1/PD-L1 immune checkpoint inhibitors (ICI) and CAR-T cell therapies in relapsed/refractory (R/R) haematological malignancies. A systematic literature review was performed until 21 November 2022. Inclusion criteria: cohort studies/clinical trials aimed at evaluating the efficacy and/or safety of the combination of CAR-T cell therapy with PD-1/PD-L1 inhibitors in R/R haematological malignancies, which had reported results. Those focusing only on ICI or CAR-T separately or evaluating the combination in other non-hematological solid tumours were excluded. We used a specific checklist for quality assessment of the studies, and then we extracted data on efficacy or efficiency and safety. A total of 1867 articles were identified, and 9 articles were finally included (early phase studies, with small samples of patients and acceptable quality). The main pathologies were B-cell acute lymphoblastic leukaemia (B-ALL) and B-cell non-Hodgkin’s lymphoma (B-NHL). The most studied combination was tisagenlecleucel with pembrolizumab. In terms of efficacy, there is great variability: the combination could be a promising option in B-ALL, with modest data, and in B-NHL, although hopeful responses were received, the combination does not appear better than CAR-T cell monotherapy. The safety profile could be considered comparable to that described for CAR-T cell monotherapy.Peer reviewe

Toxicity of the dendrimers on cultured Treg cells.

<p>The percentage of living Treg cells treated with cationic or anionic carbosilane dendrimers was analyzed by flow cytometry after 48 hours of treatment. Viability of Treg were calculated and normalized regarding the non-treated Treg condition. Mean + SEM of 2G-NN16 (n = 8), 1G-03NN12 (n = 5), 2G-03NN12 (n = 7), 2G-S24P(n = 7), 2G-S16 (n = 5), and G3-S16 (n = 4) independent experiments are showed. *<i>p</i>< 0.05 in the Mann Whitney test.</p

Suppressive capacity of Treg cells treated with dendrimers.

<p>Mean + SEM of the percentage of CD69 and CD154 activation markers in stimulated allogeneic PBMC alone (PBM ST) and co-cultured with Treg cells treated or non-treated (Treg NT) with cationic or anionic dendrimers (Treg: PBMC ratio of 1:1). Treg NT (n = 5), 1G-03NN12 (n = 4), 2G-03NN12 (n = 3), 2G-S24P (n = 5) and 2G-S16 (n = 3).**<i>p</i><0.01; *<i>p</i><0.05 with the Mann Whitney test.</p

HIV infection of Treg cells treated with dendrimers.

<p>(A) Mean ± SEM values of intracellular p24gag at 3 days post-infection determined by frequency of KC57 (p24gag) in Treg infected with X4-tropic HIV_NL4.3 (MOI 0.1) (n = 6), HIV_NL4-3 + 2G-S24P (n = 6), HIV_NL4.3 + 2G-S16 (n = 4) and HIV_NL4.3 + AZT (n = 4). (B) Mean ± SEM values of p24gag (ng/ml) production at 5 days post-infection determined by ELISA in supernatants of Treg infected with X4-tropic HIV_NL4.3 (n = 5), HIV_NL4.3 + 2G-S24P (n = 3), HIV_NL4.3 + 2G-S16 and HIV_NL4.3 + AZT (n = 5). **<i>p</i>< 0.01; *<i>p</i>< 0.05 were obtained with the Mann Whitney test.</p

Phenotype expression in Treg cells treated with dendrimers.

<p>The percentage of CD4 (A), CD45RO (B), CD38 (C) and HLA-DR (D) expression was analyzed after 48 hours of Treg cells treated with cationic or anionic dendrimers. Values were calculated and normalized regarding the non-treated Treg (Treg NT) condition that was considered as 100% of expression. Average of 2G-NN16 (n = 7), 1G-03NN12 (n = 5), 2G-03NN24 (n = 7), 2G-S24P (n = 7), 2G-S16 (n = 4), and G3-S16 (n = 4) experiment (Mean + SEM). *<i>p</i><0.05 obtained with the Wilcoxon paired test.</p

Foxp3 expression in Treg cells infected with HIV-1.

<p>Mean ± SEM values of frequency of Foxp3 in Treg infected with X4-tropic HIV_NL4.3 (MOI 0.1), HIV_NL4.3 + 2G-S24P (10μM), HIV_NL4.3 + 2G-S16 (10μM) or HIV_NL4.3 + AZT (5μM) at 5 days post-infection. Average of Treg NI and X4-tropic HIV_NL4.3 (n = 6), 2G-S24P (n = 6), 2G-S16 and AZT (n = 3) independent experiments.*<i>p</i><0.05 obtained with the Mann Whitney test.</p