Raquel Lorente

Preterm neonates show marked leukopenia and lymphopenia that are associated with increased regulatory T-cell values and diminished IL-7

Introduction:Current advances in neonatology have improved survival among preterm and low-birth-weight infants. However, the risk of neonatal death in preterm infants is much greater than in full-term neonates and is frequently associated with infections.Methods:Little is known about the immune status of preterm neonates; therefore, we analyzed the frequency and absolute counts of different immune populations in 211 cord blood samples taken from very-preterm to full-term neonates.Results:We found that absolute counts of all the immune subsets analyzed (i.e., monocytes, granulocytes, B cells, natural killer (NK) cells, CD4+, and CD8+ T cells) were markedly lower in preterm infants than in full-term infants. Surprisingly, we observed that regulatory T cells (Tregs) were the only cell subset that did not decrease in preterm infants, and their frequency was even higher than in full-term infants.Discussion:Tregs are crucial to maternal–fetal tolerance, but their suppressive role could be also implicated in the leukopenia observed in preterm infants. We did not observe differences in thymic function, but we found that plasma levels of interleukin (IL)-7 and the frequency of its receptor were significantly decreased in preterm infants. Our results could help to identify leukopenia and to implement immune therapies that significantly diminish mortality in preterm neonates.

Synergistic activity profile of carbosilane dendrimer G2-STE16 in combination with other dendrimers and antiretrovirals as topical anti-HIV-1 microbicide

UNLABELLED Polyanionic carbosilane dendrimers represent opportunities to develop new anti-HIV microbicides. Dendrimers and antiretrovirals (ARVs) acting at different stages of HIV replication have been proposed as compounds to decrease new HIV infections. Thus, we determined the potential use of our G2-STE16 carbosilane dendrimer in combination with other carbosilane dendrimers and ARVs for the use as topical microbicide against HIV-1. We showed that these combinations obtained 100% inhibition and displayed a synergistic profile against different HIV-1 isolates in our model of TZM.bl cells. Our results also showed their potent activity in the presence of an acidic vaginal or seminal fluid environment and did not activate an inflammatory response. This study is the first step toward exploring the use of different anionic carbosilane dendrimers in combination and toward making a safe microbicide. Therefore, our results support further studies on dendrimer/dendrimer or dendrimer/ARV combinations as topical anti-HIV-1 microbicide. FROM THE CLINICAL EDITOR This paper describes the first steps toward the use of anionic carbosilane dendrimers in combination with antivirals to address HIV-1, paving the way to further studies on dendrimer/dendrimer or dendrimer/ARV combinations as topical anti-HIV-1 microbicides.

Hepatitis C virus infection is associated with endothelial dysfunction in HIV/hepatitis C virus coinfected patients.

Objective:To quantify serum levels of intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) in HIV/HCV coinfected patients to examine their association with several clinical and epidemiological characteristics and the therapeutic responsiveness to interferon (IFN)-α and ribavirin therapy (IFN-α + RBV). Design:Retrospective study. Methods:We carried out a cross-sectional study with 183 IFN-α-naive patients on HAART, and 24 healthy controls. We also analyzed 30 out of 183 patients on IFN-α + RBV for the duration of 48 weeks. Results:HIV/HCV coinfected patients had higher levels of sICAM-1 and sVCAM-1 than the healthy control group (P < 0.05). Patients with HCV-genotype 1, advanced fibrosis (F≥3) or moderate to severe activity grade (A≥2) had the highest values of sICAM-1 and sVCAM-1. When we carried out a multivariate analysis, we found a significant positive relationship between both HCV-genotype 1 and advanced fibrosis (F≥3) with sICAM-1 (R = 0.549; P < 0.001); and a significant positive relationship between HCV-genotype 1 and advanced fibrosis (F≥3) with sVCAM-1 (R = 0.624; P < 0.001). We also found a positive relationship of sICAM-1 or sVCAM-1 levels with transaminases and alkaline phosphatase circulation levels (P < 0.05). Nonresponder patients had higher sICAM-1 and sVCAM-1 serum levels, and patients with sustained virologic response had significantly lower levels of sICAM-1 (P = 0.001) and sVCAM-1 (P = 0.019). Conclusion:HIV and HCV coinfection induces alterations in sICAM-1 and sVCAM-1 serum levels, which were higher in patients with HCV-genotype 1 and advanced stage of HCV infection. However, response to IFN-α + RBV may reduce these cardiovascular risk markers.

Amphiphilic cationic carbosilane-PEG dendrimers: synthesis and applications in gene therapy.

Here we synthesized carbosilane, generation 1 to 3, and PEG-based dendrons functionalized at the periphery with NHBoc groups and at the focal point with azide and alkyne moieties, respectively. The coupling of these two types of dendrons via click chemistry led to the formation of new hybrid dendrimers with two distinct moieties, the hydrophobic carbosilane and the hydrophilic PEG-based dendron. The protected dendrimers were transformed into cationic ammonium dendrimers. These unique amphiphilic dendrimers were studied as vectors for gene therapy against HIV in peripheral blood mononuclear cells (PBMC) and their performance was compared with that of a PEG-free carbosilane dendrimer. The presence of the PEG moiety afforded lower toxicities and evidenced a weaker interaction between dendrimers and siRNA when compared to the homodendrimer analogous. Both features, lower toxicity and lower dendriplex strength, are key properties for use of these vectors as carriers of nucleic material.

Oral immunotherapy in hen’s egg-allergic children increases a hypo-proliferative subset of CD4+ T cells that could constitute a marker of tolerance achievement

Background:  Food allergy affects a significant number of children and its prevalence, and persistence is undergoing an important increase in the last years. Specific oral tolerance induction (SOTI) is a promising therapy for food allergy. However, little is known about the immune mechanisms implicated in the desensitization to allergens. Our purpose was to study which immune parameters are modified during the process of tolerance achievement with the goal of identifying markers of tolerance induction.

Can serum hyaluronic acid replace simple non-invasive indexes to predict liver fibrosis in HIV/Hepatitis C coinfected patients?

BackgroundHyaluronic acid (HA) serum levels correlate with the histological stages of liver fibrosis in hepatitis C virus (HCV) monoinfected patients, and HA alone has shown very good diagnostic accuracy as a non-invasive assessment of fibrosis and cirrhosis. The aim of this study was to evaluate serum HA levels as a simple non-invasive diagnostic test to predict hepatic fibrosis in HIV/HCV-coinfected patients and to compare its diagnostic performance with other previously published simple non-invasive indexes consisting of routine parameters (HGM-1, HGM-2, Forns, APRI, and FIB-4).MethodsWe carried out a cross-sectional study on 201 patients who all underwent liver biopsies and had not previously received interferon therapy. Liver fibrosis was determined via METAVIR score. The diagnostic accuracy of HA was assessed by area under the receiver operating characteristic curves (AUROCs).ResultsThe distribution of liver fibrosis in our cohort was 58.2% with significant fibrosis (F≥2), 31.8% with advanced fibrosis (F≥3), and 11.4% with cirrhosis (F4). Values for the AUROC of HA levels corresponding to significant fibrosis (F≥2), advanced fibrosis (F≥3) and cirrhosis (F4) were 0.676, 0.772, and 0.863, respectively. The AUROC values for HA were similar to those for HGM-1, HGM-2, FIB-4, APRI, and Forns indexes. The best diagnostic accuracy of HA was found for the diagnosis of cirrhosis (F4): the value of HA at the low cut-off (1182 ng/mL) excluded cirrhosis (F4) with a negative predictive value of 99% and at the high cut-off (2400 ng/mL) confirmed cirrhosis (F4) with a positive predictive value of 55%. By utilizing these low and high cut-off points for cirrhosis, biopsies could have theoretically been avoided in 52.2% (111/201) of the patients.ConclusionsThe diagnostic accuracy of serum HA levels increases gradually with the hepatic fibrosis stage. However, HA is better than other simple non-invasive indexes using parameters easily available in routine clinical practice only for the diagnosing of cirrhosis.

Serum levels of fibrosis biomarkers measured early after liver transplantation are associated with severe hepatitis C virus recurrence.

Abstract: This prospective study analyzed the relationship between several biological markers related to liver fibrosis at 3 months and 1 year post liver transplantation in 37 patients (19 with hepatitis C virus [HCV], 18 with alcoholic liver disease). Severe HCV recurrence (HCV‐SR) was defined as fibrosis stage ≥F1 (METAVIR score) at 1 year and/or a value of hepatic venous pressure gradient ≥6 mmHg. We found HCV‐SR patients had higher values of monocyte chemotactic protein‐1 (MCP‐1), soluble vascular cell adhesion molecule‐1 (sVCAM‐1), and hyaluronic acid (HA) than non‐severe HCV recurrence patients (P<0.05). Moreover, receiver operating characteristic curve analysis showed that interferon‐inducible protein 10 (IP‐10) (area under the curve [AUC]: 0.74; confidence interval [CI] 95%: 0.49–0.91; P=0.043), MCP‐1 (AUC: 0.78; CI 95%: 0.54–0.94; P=0.007), sVCAM‐1 (AUC: 0.89; CI 95%: 0.67–0.98; P=0.005), and HA (AUC: 0.80; CI 95%: 0.55–0.94; P=0.035) have good predictive capacity for identifying severe HCV infection. The evaluation of these biomarkers may be useful in the early identification of patients in whom a more aggressive therapeutic approach could be necessary.

Sustained virological response to interferon-α plus ribavirin decreases inflammation and endothelial dysfunction markers in HIV/HCV co-infected patients

OBJECTIVES Hepatitis C virus (HCV) antiviral therapy might lead to decreased chronic immune activation and endothelial dysfunction associated with cardiovascular risk. The aim was to evaluate the effect of HCV eradication on serum markers of inflammation and endothelial dysfunction markers in HIV/HCV co-infected patients. METHODS We carried out a retrospective study of 69 HIV/HCV co-infected patients on interferon (IFN)-α plus ribavirin. In addition, 47 HIV-infected subjects were selected as a control group. A sustained virological response (SVR) was defined as an undetectable HCV viral load up to 24 weeks after the end of treatment. Tumour necrosis factor (TNF) receptor-1 (TNF-R1), soluble E-selectin (sE-selectin), soluble P-selectin (sP-selectin), soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular cell adhesion molecule 1 (sVCAM-1) were measured using a multiplex immunoassay kit. RESULTS HIV/HCV co-infected patients had higher values of soluble TNF-R1 (sTNF-R1), sE-selectin and sICAM-1 than HIV mono-infected patients (P < 0.05). SVR patients had a decrease in sTNF-R1, sP-selectin, sE-selectin and sICAM-1 during anti-HCV treatment (P < 0.05) and, at the end of treatment, SVR patients had lower values of sTNF-R1, sE-selectin and sVCAM-1 than non-responder patients (P < 0.05), although the values of sTNF-R1, sP-selectin, sE-selectin and sICAM-1 remained higher than in HIV mono-infected patients (P < 0.05). Moreover, we found a significant positive relationship between an increase in sTNF-R1 and increases in sP-selectin, sE-selectin and sICAM-1 during anti-HCV therapy. CONCLUSIONS Chronic hepatitis C infection induces alterations of markers of inflammation and endothelial dysfunction. Eradication of HCV, following IFN-α and ribavirin therapy, reduces immune activation as well as markers of inflammation and endothelial dysfunction.

Induction of Treg cells after oral immunotherapy in hen's egg-allergic children

To the Editor, Food allergy affects a significant number of children and is the most frequent reason for anaphylactic reactions at this age. Specific oral tolerance induction (SOTI) is an increasingly attractive strategy, and success has been achieved in a majority of patients. However, the immunologic mechanisms underlying SOTI are still unclear and additional advances in such therapies will require a greater understanding of the mechanism of tolerance/desensitization induction. We have recently published that allergic children have increased frequencies and absolute counts of effector-memory CD4 T cells (TEM) in comparison with non-allergic children (1) and tolerance achievement after SOTI normalized the levels of these TEM (1). TEM is a subset of cells with immediate effector function that can rapidly produce inflammatory mediators, playing a key role in food allergy (1, 2). In addition to the deletion of reactive lymphocytes, the generation of regulatory T cells (Treg) has been also postulated as a mechanism capable of preventing inappropriate reactivity against innocuous antigens. Treg cells are a subset of CD4 T cells with suppressive function (3), which have demonstrated in animal models a crucial role in the oral tolerance to food antigens (4). However, whether Treg are implicated in the SOTI-mediated desensitization to food allergens has not been elucidated in humans. Here, we performed an analysis of immune subsets in 18 eggallergic children [mean (range) age = 9.26 (4–14) years], following a SOTI protocol with egg, comparing immune values before SOTI (T0) and when egg desensitization was achieved (Tend). All subjects had histories of acute clinical reactions to egg, including immediate reactions (urticaria, vomiting, and/or anaphylaxis), a positive egg-white skin prick test (SPT), and a positive serum-specific IgE. Prior to being included to the desensitization protocol, the clinical history records and immunological analysis were reassessed and an oral challenge test with egg was carried out on those who had not had clinical episodes within the last 3 months. A SOTI protocol with powdered pasteurized egg mixed with juice or milkshakes was established enabling patients to continue treatment at home, with periodic weekly visits to the outpatient allergy department. On the first day, fractionated doses were administered until reaching 31 mg of egg. Subsequently, weekly increases were made in the clinic until 10 g of powdered egg, the equivalent of one egg, was reached. All the children enrolled in this study achieved a complete desensitization to egg. A child was considered desensitized when he was capable of ingesting 10 gr of powdered egg without any adverse reactions. A normal diet including egg was recommended to patients after desensitization achievement. 22 age-matched healthy children were also studied as control group [mean (range) age = 7.20 (3–13) years]. The study was conducted according to the Declaration of Helsinki, approved by the clinical ethics committee of the center, and written informed consent was obtained from all legal guardians. Percentage and absolute counts of Treg, CD4 T-cell subsets, monocytes, basophils, and granulocytes were determined in fresh peripheral blood samples as previously described (5).

Adipokine profiles and lipodystrophy in HIV-infected children during the first 4 years on highly active antiretroviral therapy.

The aim of the study was to evaluate the evolution of plasma adipokines and lipodystrophy in protease inhibitor‐naïve vertically HIV‐infected children on highly active antiretroviral therapy (HAART).