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Regulatory T cells (Tregs) expressing chimeric antigen receptors (CAR) are a promising tool to promote transplant tolerance. The relationship between CAR structure and Treg function was studied in xenogeneic, immunodeficient mice, revealing advantages of CD28-encoding CARs. However, these models could underrepresent interactions between CAR-Tregs, antigen-presenting cells (APCs) and donor-specific antibodies. We generated mouse Tregs expressing HLA-A2-specific CARs with different costimulatory domains and compared their function in vitro and in vivo. In vitro assays revealed the CD28-encoding CAR had superior antigen-specific suppression, proliferation and cytokine production. In contrast, in vivo protection from skin allograft rejection and alloantibody production was similar between Tregs expressing CARs encoding CD28, ICOS or PD1, but not GITR, 41BB or OX40, co-stimulatory domains. To reconcile in vitro and in vivo data, we analyzed effects of a CAR encoding CD3ζ but no co-stimulatory domain. These data revealed that exogenous co-stimulation via APCs can compensate for the lack of a CAR-encoded CD28 domain. Thus, Tregs expressing a CAR with or without CD28 are functionally equivalent in vivo. This study reveals a new dimension of CAR-Treg biology and has important implications for the design of CARs for clinical use in Tregs.

Cell therapy with autologous donor-specific regulatory T cells (Tregs) is a promising strategy to minimize immunosuppression in transplant recipients. Chimeric antigen receptor (CAR) technology has recently been used successfully to generate donor-specific Tregs and overcome the limitations of enrichment protocols based on repetitive stimulations with alloantigens. However, the ability of CAR-Treg therapy to control alloreactivity in immunocompetent recipients is unknown. We first analyzed the effect of donor-specific CAR Tregs on alloreactivity in naive, immunocompetent mice receiving skin allografts. Tregs expressing an irrelevant or anti-HLA-A2-specific CAR were administered to Bl/6 mice at the time of transplanting an HLA-A2+ Bl/6 skin graft. Donor-specific CAR-Tregs, but not irrelevant-CAR Tregs, significantly delayed skin rejection and diminished donor-specific antibodies (DSAs) and frequencies of DSA-secreting B cells. Donor-specific CAR-Treg-treated mice also had a weaker recall DSA response, but normal responses to an irrelevant antigen, demonstrating antigen-specific suppression. When donor-specific CAR Tregs were tested in HLA-A2-sensitized mice, they were unable to delay allograft rejection or diminish DSAs. The finding that donor-specific CAR-Tregs restrain de novo but not memory alloreactivity has important implications for their use as an adoptive cell therapy in transplantation.

Up to 40% of newly diagnosed cases of HIV-1 infection are late diagnoses, with a profound decrease in CD4 cell counts in many cases. One-third of these individuals do not achieve optimal CD4 cell recovery (OR) after suppressive antiretroviral treatment (ART). This retrospective/longitudinal study of poor recovery (PR) included 79 HIV-1-infected individuals with CD4 count, This work was supported in part by the Spanish AIDS Network “Red de Investigación en Sida (RIS)” RD16/0025/0001; Ayudas contratación de ayudantes de investigación y técnicos de laboratorio, Consejería de Educación, Juventud y Deporte de la Comunidad de Madrid (PEJ15/bio/tl-0064 to MJRL and PEJ17/AI_BMD-6683 to FHW); Health Institute Carlos III, PI18/01216; Junta de Andalucía, Consejería de Economía, Innovación, Ciencia y Empleo, Proyecto de Investigación de Excelencia CTS2593; YMP was supported by the Consejería de Salud y Bienestar Social of Junta de Andalucía through the “Nicolás Monardes” programme (C-0013-2017).

The CD4/CD8 T-cell ratio is emerging as a relevant marker of evolution for many pathologies and therapies. We aimed to explore immunological features beyond CD4/CD8 ratio values in older subjects (>65 years old) who were classified as having lower (2) ratio values. The lower group showed a lower thymic output (sj/β-TREC ratio) and frequency of naïve T-cells, concomitant with increased mature T-cells. In these subjects, the CD4 T-cell subset was enriched in CD95+ but depleted of CD98+ cells. The regulatory T-cell (Treg) compartment was enriched in CTLA-4+ cells. The CD8 T-cell pool exhibited increased frequencies of CD95+ cells but decreased frequencies of integrin-β7+ cells. Interestingly, in the intermediate group, the CD4 pool showed greater differences than the CD8 pool, mostly for cellular senescence. Regarding inflammation, only hsCRP was elevated in the lower group; however, negative correlations between the CD4/CD8 ratio and β2-microglobulin and sCD163 were detected. These subjects displayed trends of more comorbidities and less independence in daily activities. Altogether, our data reveal different thymic output and immune profiles for T-cells across CD4/CD8 ratio values that can define immune capabilities, affecting health status in older individuals. Thus, the CD4/CD8 ratio may be used as an integrative marker of biological age., This work was supported by grants from the Fondo de Investigación Sanitaria (FIS; PI18/01216), which is co-funded by Fondos Europeos para el Desarrollo Regional (FEDER) “Una manera de hacer Europa” and the Junta de Andalucía, Consejería de Economía, Innovación, Ciencia y Empleo (Proyecto de Investigación de Excelencia; CTS2593). The Spanish AIDS Research Network of Excellence also supported this study (RD16/0025/0019). V G-R, I O-M and A B-R were supported by Instituto de Salud Carlos III (FI19/00298, CM19/00051 and CD19/00143, respectively). YM. P was supported by the Consejería de Salud y Familias of Junta de Andalucía through the ‘‘Nicolás Monardes’’ program (C-0013-2017).

The immunological, biochemical and molecular mechanisms associated with poor immune recovery are far from known, and metabolomic profiling offers additional value to traditional soluble markers. Here, we present novel and relevant data that could contribute to better understanding of the molecular mechanisms preceding a discordant response and HIV progression under suppressive combined antiretroviral therapy (cART). Integrated data from nuclear magnetic resonance (NMR)-based lipoprotein profiles, mass spectrometry (MS)-based metabolomics and soluble plasma biomarkers help to build prognostic and immunological progression tools that enable the differentiation of HIV-infected subjects based on their immune recovery status after 96 weeks of suppressive cART. The metabolomic signature of ART-naïve HIV subjects with a subsequent late immune recovery is the expression of pro-inflammatory molecules and glutaminolysis, which is likely related to elevate T-cell turnover in these patients. The knowledge about how these metabolic pathways are interconnected and regulated provides new targets for future therapeutic interventions not only in HIV infection but also in other metabolic disorders such as human cancers where glutaminolysis is the alternative pathway for energy production in tumor cells to meet their requirement of rapid proliferation.

Lentivirus-mediated gene transfer is an efficient method to introduce a variety of transgenes to human T cells. Here we describe a protocol to transduce human CD4

Lentivirus-mediated gene transfer is an efficient method to introduce a variety of transgenes to human T cells. Here we describe a protocol to transduce human CD4+, CD8+, or CD4+ regulatory T cells. To illustrate the method, we use transduction with lentivirus encoding an HLA-A2-specific chimeric antigen receptor (CAR) and a transduction marker as an example. Methods to isolate, transduce, purify, and expand CD4+ and CD8+ T cells as well as regulatory T cells are provided. We also describe how to carry out cytotoxicity or suppression assays to assess the function of the resulting CAR T cell or CAR regulatory T cells, respectively.

Regulatory T cells (Tregs) control immune homeostasis and prevent exacerbated immune responses, and can be used as cell therapy to dampen a variety of autoimmune or autoinflammatory responses. Treg therapy is significantly more effective if the cells are antigen-specific. One way to re-direct the specificity of Tregs is to engineer them to express a Chimeric Antigen Receptor (CAR). Proof-of-concept studies have shown the potential for "basic" models of CAR-Tregs to be used as cellular therapy in autoimmunity, organ transplantation and hematopoietic stem cell transplantation. In parallel, work in the context of cancer has significantly advanced knowledge of how to optimise CAR-T cell structure and function for more precise and potent function. In this review, we summarize the current state of knowledge about important considerations when generating CAR-Tregs. We also extrapolate from emerging findings with CAR-T cells about strategies to further improve CAR-Treg function, creating "luxury" models with refined activity.

Antigen-specific regulatory T cells (Tregs) engineered with chimeric antigen receptors (CARs) are a potent immunosuppressive cellular therapy in multiple disease models and could overcome shortcomings of polyclonal Treg therapy. CAR therapy was initially developed with conventional T cells, which have different signaling requirements than do Tregs To date, most of the CAR Treg studies used second-generation CARs, encoding a CD28 or 4-1BB co-receptor signaling domain and CD3ζ, but it was not known if this CAR design was optimal for Tregs Using a human leukocyte antigen-A2-specific CAR platform and human Tregs, we compared 10 CARs with different co-receptor signaling domains and systematically tested their function and CAR-stimulated gene expression profile. Tregs expressing a CAR encoding CD28wt were markedly superior to all other CARs tested in an in vivo model of graft-versus-host disease. In vitro assays revealed stable expression of Helios and an ability to suppress CD80 expression on dendritic cells as key in vitro predictors of in vivo function. This comprehensive study of CAR signaling domain variants in Tregs can be leveraged to optimize CAR design for use in antigen-specific Treg therapy.

SummaryAntigen-specific regulatory T cells (Tregs) engineered with chimeric antigen receptor (CARs) are a potent immunosuppressive cellular therapy in multiple disease models. To date the majority of CAR Treg studies employed second generation CARs, encoding a CD28 or 4-1BB co-receptor signaling domain and CD3ζ, but it was not known if this CAR design was optimal for Tregs. Using an HLA-A2-specific CAR platform and human Tregs, we compared ten CARs with different co-receptor signaling domains and systematically tested their function. Tregs expressing a CAR encoding wild-type CD28 were markedly superior to all other CARs tested in anin vivomodel of graft-versus-host disease. In vitro assays revealed stable expression of Helios and ability to suppress CD80 expression on DCs as keyin vitropredictors ofin vivofunction. This comprehensive study of CAR signaling-domain variants in Tregs can be leveraged to optimize CAR design for use in antigen-specific Treg therapy.

[Background] Seasonal influenza virus infection is a significant cause of morbimortality in the elderly. However, there is poor vaccine efficacy in this population due to immunosenescence. We aimed to explore several homeostatic parameters in the elderly that could impact influenza vaccine responsiveness., [Methods] Subjects (> 60 years old) who were vaccinated against influenza virus were included, and the vaccine response was measured by a haemagglutination inhibition (HAI) test. At baseline, peripheral CD4 and CD8 T-cells were phenotypically characterized. Thymic function and the levels of different inflammation-related biomarkers, including Lipopolysaccharide Binding Protein (LBP) and anti-cytomegalovirus (CMV) IgG antibodies, were also measured., [Results] Influenza vaccine non-responders showed a tendency of higher frequency of regulatory T-cells (Tregs) before vaccination than responders (1.49 [1.08–1.85] vs. 1.12 [0.94–1.63], respectively, p = 0.061), as well as higher expression of the proliferation marker Ki67 in Tregs and different CD4 and CD8 T-cell maturational subsets. The levels of inflammation-related biomarkers correlated with the frequencies of different proliferating T-cell subsets and with thymic function (e.g., thymic function with D-dimers, r = − 0.442, p = 0.001)., [Conclusions] Age-related homeostatic dysregulation involving the proliferation of CD4 and CD8 T-cell subsets, including Tregs, was related to a limited responsiveness to influenza vaccination and a higher inflammatory status in a cohort of elderly people., This work was supported by grants from the Fondo de Investigación Sanitaria (FIS; PI18/01216), which is co-funded by Fondos Europeos para el Desarrollo Regional (FEDER) and the Junta de Andalucía, Consejería de Economía, Innovación, Ciencia y Empleo (Proyecto de Investigación de Excelencia; CTS2593). The Spanish AIDS Research Network of Excellence also supported this study (RD16/0025/0019). YM.P was supported by the Consejería de Salud y Bienestar Social of Junta de Andalucía through the “Nicolás Monardes” programme (C-0013-2017).

Background Maraviroc-containing combined antiretroviral therapy (MVC-cART) improved the response to the hepatitis B virus (HBV) vaccine in HIV-infected subjects younger than 50 years old. We aimed here to explore the effect of this antiretroviral therapy on different immunological parameters that could account for this effect. Methods We analysed baseline samples of vaccinated subjects under 50 years old (n = 41). We characterized the maturational subsets and the expression of activation, senescence and prone-to-apoptosis markers on CD4 T-cells; we also quantified T-regulatory cells (Treg) and dendritic cell (DC) subsets. We used binary logistic regression to evaluate the immunological impact of MVC-cART, correlation with MVC exposure and linear regression for association with the magnitude of the HBV vaccine response. Results HIV-infected subjects on MVC-cART prior to vaccination showed increased recent thymic emigrants levels and reduced myeloid-DC levels. A longer exposure to MVC-cART was associated with lower frequencies of Tregs and activated and proliferating CD4 T-cells. Furthermore, the frequencies of activated and proliferating CD4 T-cells were inversely associated with the magnitude of the HBV vaccine response. Conclusion The beneficial effect of MVC-cART in the HBV vaccine response in subjects below 50 years old could be partially mediated by its reducing effect on the frequencies of activated and proliferating CD4 T-cells prior to vaccination. Electronic supplementary material The online version of this article (10.1186/s12967-018-1617-1) contains supplementary material, which is available to authorized users.

IntroductionWe previously found that a maraviroc-containing combined antiretroviral therapy (MVC-cART) was associated with a better response to the Hepatitis B Virus (HBV) vaccine in HIV-infected subjects younger than 50 years old. We aimed here to extend our previous analysis including immunological parameters related to inflammation, T-cell and dendritic cell (DC) subsets phenotype and to explore the impact of MVC-cART on these parameters.MethodsWe analyzed baseline samples of vaccinated subjects under 50 years old (n=41). We characterized CD4 T-cells according to the distribution of their maturational subsets and the expression of activation, senescence and prone-to-apoptosis markers; we also quantified Treg-cells and main DC subsets. Linear regressions were performed to determine the impact of these variables on the magnitude of vaccine response. Binary logistic regressions were explored to analyze the impact of MVC-cART on immunological parameters. Correlations with the time of MVC exposure were also explored.ResultsMVC-cART remained independently associated with HBV-vaccine responsiveness even after adjusting by immunological variables. The %CD4+CD25hiFoxP3+ki67+ and %pDCs were also independently associated. Moreover, HIV-infected subjects on MVC-containing therapy prior to vaccination showed lower inflammatory levels, activated CD4 T-cells and frequency of Treg cells and higher frequency of recent thymic emigrants.ConclusionTreg-cell levels negatively impacted the HBV-vaccine response, whereas higher pDCs levels and a MVC-cART prior to vaccination were associated with better responsiveness. These factors together with the improved phenotypic CD4 T-cell profile and the lower inflammatory levels found in subjects with a MVC-cART prior HBV vaccination could contribute to their enhanced vaccine response.

[Objective] Cardiovascular diseases (CVDs) are one of the main causes of morbimortality in HIV-infected patients on suppressive antiretroviral therapy. The objective of this work was to evaluate the role of single nucleotide polymorphisms (SNPs) in lipopolysaccharide (LPS) Toll-like receptor 4 (TLR4) and CVDs occurrence in HIV-infected patients. Additionally, the functional consequences of carrying these SNPs were analyzed., [Methods] The association of TLR4 SNPs, Asp299Gly/Thr399Ile with CVDs occurrence was analyzed using multivariate logistic regression models. Clinical, immunological, and traditional cardiovascular risk factors were used as covariates. The monocyte phenotype and response were assessed by multiparametric flow cytometry comparing carriers with noncarriers of this SNP., [Results] Asp299Gly SNP, assayed in 253 HIV-infected patients, was independently associated with the occurrence of CVDs after adjusting for CD4+ T-cell nadir, HCV-coinfection, bacterial pneumonia, diabetes mellitus, and traditional cardiovascular risk factors [odds ratio (confidence interval 95%) = 3.672 (1.061–12.712), P = 0.04). Carriers of Asp299Gly SNP showed higher percentage of patrolling and intermediate monocytes producing a proinflammatory combination of cytokines compared with noncarriers (P = 0.037 and P = 0.046, respectively). Intermediate monocyte subset levels correlated with soluble interleukin-6 levels only in carriers (r = 0.89; P = 0.01)., [Conclusion] TLR4 Asp299Gly polymorphism is independently associated with the occurrence of CVDs in HIV-infected patients. The proinflammatory profile associated to this variant could be involved in the development of atherosclerotic pathologies.

The size of peripheral T-cell pool is kept constant throughout life. However, a decline in lymphocyte numbers is a feature of several human disorders, in which fast and slow homeostatic proliferation play a crucial role. Several in vitro and in vivo models have been developed to study such processes. Nevertheless, self- and commensal- antigens, well-known triggers of homeostatic proliferation, have not been examined in these models. We have designed an in vitro culture of human T-cells exposed to rIL7 and autologous antigen-presenting cells (aAPC) that allows the simultaneous characterization of the different types of homeostatic proliferation. Using our model, we first confirmed that both rIL7 and aAPC are survival signals ultimately leading to homeostatic proliferation. In addition, we explored the modulation of different anti-apoptotic, proliferative, activation and homing markers during fast and slow homeostatic proliferation. Finally, different subsets of Treg were generated during homeostatic proliferation in our model. In summary, our in vitro system is able to simultaneously reproduce both types of homeostatic proliferation of human naive CD4 T-cells, and allows the characterization of these processes. Our in vitro system is a useful tool to explore specific features of human homeostatic proliferation in different human lymphopenia-related disorders and could be used as a cell therapy approach.

The response to the HBV vaccine in HIV-infected patients is deficient. Our aim was to analyze whether a suppressive combined antiretroviral treatment (cART) containing maraviroc (MVC-cART) was associated with a better response to HBV vaccine. Fifty-seven patients on suppressor cART were administered the HBV vaccine. The final response, the early response, and the maintenance of the response were assessed. An anti-HBs titer of >10 mIU/ml was considered a positive response. A subgroup of subjects was simultaneously vaccinated against hepatitis A virus (HAV). Lineal regression analyses were performed to determine demographic, clinical, and immunological factors associated with the anti-HBs titer. Vaccine response was achieved in 90% of the subjects. After 1 year, 81% maintained protective titers. Only simultaneous HAV vaccination was independently associated with the magnitude of the response in anti-HBs titers, with a P value of 0.045 and a regression coefficient (B) [95% confident interval (CI)] of 236 [5 to 468]. In subjects ≤50 years old (n = 42), MVC-cART was independently associated with the magnitude of the response (P = 0.009; B [95% CI], 297 [79 to 516]) together with previous vaccination and simultaneous HAV vaccination. High rates of HBV vaccine response can be achieved by revaccination, simultaneous HAV vaccination, and administration of cARTs including MVC. MVC may be considered for future vaccination protocols in patients on suppressive cART., This study was funded by an investigator-initiated research grant from ViiV Healthcare S.L. (grant number 205644) and by grants from the Fondo de Investigación Sanitaria (FIS; PI14/01693; PI16/01863), cofunded by Fondos Europeos para el Desarrollo Regional (FEDER) and the Junta de Andalucía, Consejería de Economía, Innovación, Ciencia y Empleo (Proyecto de Investigación de Excelencia; CTS2593). The Spanish AIDS Research Network of Excellence also supported this study (RD16/0025/0019). E.R.-M. and Y.M.P. were supported by the Fondo de Investigación Sanitaria through the ‘Miguel Servet’ programs (CPII014/00025 and CPII13/00037, respectively). Y.M.P. was supported by the Consejería de Salud y Bienestar Social of Junta de Andalucía through the ‘Nicolás Monardes’ program (C-0010/13). L.T.-D. was supported by Instituto de Salud Carlos III (PFIS program; FI00/00431).

Summary Background Despite the fact that antiretroviral therapy (cART) suppresses HIV-viremia, an adequate CD4 T-cell recovery is not always achieved (immunodiscordant response to cART). IL17a-producing CD4 T-cells (Th17) constitutes an important subset involved in the preservation of mucosal surfaces integrity, which depletion has been associated with disease progression in HIV-infection. However, whether Th17 frequency at cART initiation is associated with a poor CD4 T-cell recovery has not been yet explored. Our aim was to explore whether the Th17 cells and other IL17a-producing T-cell subsets at cART initiation were associated with a subsequent immunodiscordant response to cART. Methods We selected pre-cART samples of antiretroviral-naive subjects with and without a low CD4 recovery after cART (LR-subjects and HR-subjects, respectively). Peripheral blood mononuclear cells (PBMCs) were stimulated with PMA/ionomycine, and the production of several cytokines including IL17a was analyzed by flow cytometry. Results A trend to higher Th17 ( p = 0.05) and increased frequencies of IL17a-producing Treg ( p = 0.011) was found in LR-subjects before cART onset. Despite increased frequencies of both Treg and Th17 in LR-subject at cART initiation, no alteration of Treg/Th17 ratio was observed. While polifunctional profile of CD4 T-cells was not different, frequencies of CD4 T-cells producing cytokine-combinations including IL17a were increased in LR-subjects. Conclusion Increased frequencies of Th17, IL17a-producing Treg and CD4 T-cells producing specific IL17a-containing combinations of cytokines, precede the immunodiscordant response to cART, suggesting a potential contribution of these subsets in such anomalous response to cART.

Immunological characterization of HIV-infected subjects with low CD4-recovery (LR-subjects) has been extensively performed after a variable period of combined antiretroviral therapy (cART). We now explore immunological alterations present before the cART onset. In a case-control study, we selected pre-cART samples of HIV-subjects with and without low CD4-recovery after CART (n = 21 per group). CD4 T-cell activation, senescence and exhaustion related markers were not found specifically altered before cART initiation. On the other hand, we found that LR-subjects before cART already showed increased levels of IL6 (p = 0.009) and increased frequencies of Ki67+FCD4(+) T-cells (p = 0.026), CD45RA-CD27+CD4(+) T-cells (p = 0.008) and Treg (p = 0.001), as well as increased expression of CD95 and CD127 on CD4 T-cells (p = 0.016; p = 0.032, respectively). These parameters characterize the immunological damage in LR-subjects before the cART onset and could be associated to the mechanisms hindering the subsequent CD4 recovery. (C) 2017 Elsevier B.V. All rights reserved.

Background The persistence of an inverted CD4/CD8 ratio has been extensively associated with the increased morbimortality of chronic human immunodeficiency virus (HIV)-infected subjects. Thymic function is crucial for the maintenance of T cell homeostasis. We explored the impact of thymic function on the CD4/CD8 ratio of HIV-infected subjects. Methods In a cohort of 53 antiretroviral-naive HIV-infected subjects, the measure of thymic volume, as a representative marker for thymic function, was available at baseline and at 12, 24, and 48 weeks post antiretroviral treatment. Results Baseline thymic volume was associated with the CD4/CD8 ratio ( Ρ: = 0.413, P = .002), being this association highly dependent on the CD4 T cell levels. In subjects who achieved undetectable viral load after treatment (n = 33), a higher baseline thymic volume was associated with a higher increase in CD4 T cell counts and a decreasing trend in CD8 T cell counts during follow-up. Moreover, the baseline thymic volume was independently associated with the normalization of the CD4/CD8 ratio after 96 weeks of treatment (odds ratio, 95% confidence interval: 1.95 (1.07-3.55); P = .03). Conclusions Our data indicate the relevance of the remaining thymic function before the start of treatment to the CD4/CD8 ratio of HIV- infected subjects and, hence, potentially, in their clinical progression.

Regulatory T (Treg) cells comprise different functional subsets with different CCR5 expression. Treg homeostasis is disrupted by HIV but the effect of treatment has barely been explored. In a longitudinal design, we compared the effect of a maraviroc-containing (n = 9) or sparing (n = 12) therapy in antiretroviral-naive HIV-positive participants on peripheral FoxP3low CD45RA+ (nTreg), FoxP3high CD45RA– (eTreg) and FoxP3low CD45RA– (non-Treg) cells. Maraviroc significantly reduced all subsets in the short-term and, except for nTreg cells, also normalized them in the long-term. The correlation between eTreg cells and CD4 counts, lost before treatment, was only restored by maraviroc. The differential effect of maraviroc on Treg subsets contributes to understanding its immunomodulatory effects., This work was supported by grants from the Fondo de Investigación Sanitaria (FIS; P11/02014), the Spanish AIDS Research Network of Excellence (RIS; RD12/0017/0029, RD12/0017/0037), the Ministerio de Sanidad, Política Social e Igualdad (EC11-520], the Fundación Progreso y Salud [PI-0081-2011], and Pfizer/ViiV Healthcare (grant numbers WS843473, WS2425049). Y.M. Pacheco was supported by the Fondo de Investigación Sanitaria through the “Miguel Servet” programs (CP07/00240, CPII13/00037), and by the Consejeria de Salud y Bienestar Social of Junta de Andalucia through the ‘Nicolas Monardes’ programme [C-0010/13]. E Ruiz-Mateos was supported by the Fondo de Investigación Sanitaria through the ‘Miguel Servet’ programme [CP08/0172]. M.R. Benhnia was supported by the Ministry of Economy and Competitiveness (Ramon y Cajal grant RYC-2010-07419).