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Type 1 diabetes (T1D) is characterized by an immune-mediated progressive destruction of the insulin-producing β-cells. Proinflammatory cytokines trigger endoplasmic reticulum (ER) stress and subsequent insulin secretory deficiency in cultured β-cells, mimicking the islet microenvironment in T1D. β-cells undergo physiologic ER stress due to the high rate of insulin production and secretion under stimulated conditions. Severe and uncompensated ER stress in β-cells is induced by several pathological mechanisms before onset and during T1D. We previously described that the small drug Compound A (CpdA), a selective glucocorticoid receptor (GR/NR3C1, nuclear receptor subfamily 3, group C, member 1) ligand with demonstrated inflammation-suppressive activity in vivo, is an effective modulator of effector T and dendritic cells and of macrophages, yet, in a GR-independent manner. Here, we focus on CpdA’s therapeutic potential in T1D cellular and animal models. We demonstrate that CpdA improves the unfolded protein response (UPR) by attenuating ER stress and favoring the survival and function of β-cells exposed to an environment of proinflammatory cytokines. CpdA administration to NODscid mice adoptively transferred with diabetogenic splenocytes (from diabetic NOD mice) led to a delay of disease onset and reduction of diabetes incidence. Histological analysis of the pancreas showed a reduction in islet leukocyte infiltration (insulitis) and preservation of insulin expression in CpdA-treated normoglycemic mice in comparison with control group. These new findings together with our previous reports justify further studies on the administration of this small molecule as a novel therapeutic strategy with dual targets (effector immune and β-cells) during autoimmune diabetes.

We describe, for the first time, a new splice variant of the human TGF-{beta} type II receptor (T{beta}RII). The new transcript lacks 149 nucleotides, causing a frameshift with the appearance of an early stop codon, rendering a truncated mature protein of 57 amino acids. The predicted protein, lacking the transmembrane domain and with a distinctive 13 amino acid stretch in the C-terminus, was named T{beta}RII-Soluble Endogenous (T{beta}RII-SE). Binding predictions indicated that the novel 13 amino acid stretch interacts with all three TGF-{beta} cognate ligands and generate a more extensive protein-protein interface than T{beta}RII. T{beta}RII-SE and human IgG1 Fc-domain, were fused in frame in a lentiviral vector (Lv) for further characterization. With this vector, we transduced 293T cells and purified T{beta}RII-SE/Fc by A/G protein chromatography from conditioned medium. Immunoblotting revealed homogeneous bands of approximately 37 kDa (reduced) and 75 kD (non-reduced), indicating that T{beta}RII-SE/Fc is secreted as a disulphide-linked homodimer. Moreover, high affinity binding of T{beta}RII-SE to the three TGF-{beta} isoforms was confirmed by Surface Plasmon Resonance (SPR) analysis. Also, intrahepatic delivery of Lv.T{beta}RII-SE/Fc in a carbon tetrachloride-induced liver fibrosis model revealed amelioration of liver injury and fibrosis. Our results indicate that T{beta}RII-SE is a novel member of the TGF-{beta} signaling pathway with distinctive characteristics. This novel protein offers an alternative tool for the prevention and treatment of pathologies caused by the overproduction of TGF-{beta} ligands.

In rheumatoid arthritis (RA) patients, TGF-β exerts a singular effect on lymphocytes, macrophages, and polymorphonuclear leukocytes. Moreover, evidences indicate that TGF-β1 stimulation affects the expression levels of TGF-β receptors. Therefore, we analysed in different leukocyte subpopulations, whether the mRNA abundance of TGFBR2 splice variants might be related to RA.We isolated different leukocyte subpopulations from peripheral blood from 9 healthy control volunteers and 9 RA patients, matched by gender and age (cohort 1), and 8 additional RA patients (cohort 2). Then we quantified, by RT-qPCR, the mRNA relative abundance of TGFBR2 splice variants (namely TGFBR2A and TGFBR2B) in PMNs, and PBMCs (monocytes and non-monocytes). We first checked whether the TGFBR2-splice variant mRNA profile could be associated with any particular blood cell type both, in healthy control volunteers and in RA patients. In addition, PBMC and PMN mRNA levels were correlated, using Spearman's rank-order correlation test, with clinical and biochemical determinations of RA patients.We have shown that TGFBR2 exhibits an alternative splicing pattern in different subpopulations of human leucocytes from healthy controls, and the lack of it in the same cell type from RA samples. Furthermore, our study yields initial evidence that TGFBR2 mRNA expression levels in monocytes might mirror RA disease activity.mRNA abundance of TGFBR2 splice variants in monocytes shows changes linked to RA disease activity.

Diaphragmatic myoblasts (DM) are stem cells of the diaphragm, a muscle displaying high resistance to stress and exhaustion. We hypothesized that DM modified to overexpress connexin-43 (cx43), seeded on aligned poly (l-lactic acid) (PLLA) sheets would decrease infarct size and improve ventricular function in sheep with acute myocardial infarction (AMI). Sheep with AMI received PLLA sheets without DM (PLLA group), sheets with DM (PLLA-DM group), sheets with DM overexpressing cx43 (PLLA-DMcx43) or no treatment (control group, n = 6 per group). Infarct size (cardiac magnetic resonance) decreased ∼25% in PLLA-DMcx43 [from 8.2 ± 0.6 ml (day 2) to 6.5 ± 0.7 ml (day 45), p

Diaphragmatic myoblasts (DMs) are precursors of type-1 muscle cells displaying high exhaustion threshold on account that they contract and relax 20 times/min over a lifespan, making them potentially useful in cardiac regeneration strategies. Besides, it has been shown that biomaterials for stem cell delivery improve cell retention and viability in the target organ. In the present study, we aimed at developing a novel approach based on the use of poly (L-lactic acid) (PLLA) scaffolds seeded with DMs overexpressing connexin-43 (cx43), a gap junction protein that promotes inter-cell connectivity. DMs isolated from ovine diaphragm biopsies were characterized by immunohistochemistry and ability to differentiate into myotubes (MTs) and transduced with a lentiviral vector encoding cx43. After confirming cx43 expression (RT-qPCR and Western blot) and its effect on inter-cell connectivity (fluorescence recovery after photobleaching), DMs were grown on fiberaligned or random PLLA scaffolds. DMs were successfully isolated and characterized. Cx43 mRNA and protein were overexpressed and favored inter-cell connectivity. Alignment of the scaffold fibers not only aligned but also elongated the cells, increasing the contact surface between them. This novel approach is feasible and combines the advantages of bioresorbable scaffolds as delivery method and a cell type that on account of its features may be suitable for cardiac regeneration. Future studies on animal models of myocardial infarction are needed to establish its usefulness on scar reduction and cardiac function., Centro de Investigaciones Cardiovasculares

Type 1 diabetes (T1DM) is a T cell-mediated autoimmune disease that selectively destroys pancreatic β cells. The only possible cure for T1DM is to control autoimmunity against β cell-specific antigens. We explored whether the natural compound curcumin, with anti-oxidant and anti-inflammatory activities, might down-regulate the T cell response that destroys pancreatic β cells to improve disease outcome in autoimmune diabetes. We employed two accelerated autoimmune diabetes models: (i) cyclophosphamide (CYP) administration to non-obese diabetic (NOD) mice and (ii) adoptive transfer of diabetogenic splenocytes into NODscid mice. Curcumin treatment led to significant delay of disease onset, and in some instances prevented autoimmune diabetes by inhibiting pancreatic leucocyte infiltration and preserving insulin-expressing cells. To investigate the mechanisms of protection we studied the effect of curcumin on key immune cell populations involved in the pathogenesis of the disease. Curcumin modulates the T lymphocyte response impairing proliferation and interferon (IFN)-γ production through modulation of T-box expressed in T cells (T-bet), a key transcription factor for proinflammatory T helper type 1 (Th1) lymphocyte differentiation, both at the transcriptional and translational levels. Also, curcumin reduces nuclear factor (NF)-κB activation in T cell receptor (TCR)-stimulated NOD lymphocytes. In addition, curcumin impairs the T cell stimulatory function of dendritic cells with reduced secretion of proinflammatory cytokines and nitric oxide (NO) and low surface expression of co-stimulatory molecules, leading to an overall diminished antigen-presenting cell activity. These in-vitro effects correlated with ex-vivo analysis of cells obtained from curcumin-treated mice during the course of autoimmune diabetes. These findings reveal an effective therapeutic effect of curcumin in autoimmune diabetes by its actions on key immune cells responsible for β cell death. Fil: Castro, Carla Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Barcala Tabarrozzi, Andrés Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Winnewisser, Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Gimeno, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Antunica Noguerol, María de Las Nieves. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Liberman, Ana Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina Fil: Paz, Dante Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina Fil: Dewey, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús. Instituto de Investigaciones Biotecnológicas (sede Chascomús); Argentina Fil: Perone, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación En Biomedicina de Buenos Aires; Argentina

Adult mesenchymal stromal cell-based interventions have shown promising results in a broad range of diseases. However, their use has faced limited effectiveness owing to the low survival rates and susceptibility to environmental stress on transplantation. We describe the cellular and molecular characteristics of multilineage-differentiating stress-enduring (Muse) cells derived from adipose tissue (AT), a subpopulation of pluripotent stem cells isolated from human lipoaspirates. Muse-AT cells were efficiently obtained using a simple, fast, and affordable procedure, avoiding cell sorting and genetic manipulation methods. Muse-AT cells isolated under severe cellular stress, expressed pluripotency stem cell markers and spontaneously differentiated into the three germ lineages. Muse-AT cells grown as spheroids have a limited proliferation rate, a diameter of ∼15 mm, and ultrastructural organization similar to that of embryonic stem cells. Muse-AT cells evidenced high stage-specific embryonic antigen-3 (SSEA-3) expression (∼60% of cells) after 7–10 days growing in suspension and did not form teratomas when injected into immunodeficient mice. SSEA-3+-Muse-AT cells expressed CD105, CD29, CD73, human leukocyte antigen (HLA) class I, CD44, and CD90 and low levels of HLA class II, CD45, and CD34. Using lipopolysaccharide-stimulated macrophages and antigen-challenged T-cell assays, we have shown that Muse-AT cells have anti-inflammatory activities downregulating the secretion of proinflammatory cytokines, such as interferon-γ and tumor necrosis factor-α.Muse-AT cells spontaneously gained transforming growth factor-β1 expression that, in a phosphorylated SMAD2-dependent manner, might prove pivotal in their observed immunoregulatory activity through decreased expression of T-box transcription factor in T cells. Collectively, the present study has demonstrated the feasibility and efficiency of obtaining Muse-AT cells that can potentially be harnessed as immunoregulators to treat immune-related disorders. Fil: Gimeno, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Fuertes, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Barcala Tabarrozzi, Andrés Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Attorressi, Alejandra I.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Cucchiani, Rodolfo. Hospital Universitario Austral; Argentina Fil: Corrales, Luis. Hospital Universitario Austral; Argentina Fil: Oliveira, Talita C.. Universidade de Sao Paulo; Brasil Fil: Sogayar, Mari C.. Universidade de Sao Paulo; Brasil Fil: Labriola, Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidade de Sao Paulo; Brasil Fil: Dewey, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Perone, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina

Tumor microenvironment is composed of different cell types including immune cells. Far from acting to eradicate cancer cells, these bone marrow-derived components could be involved in carcinogenesis and/or tumor invasion and metastasis. Here, we describe an alternative approach to treat solid tumors based on the genetic modification of hematopoietic stem and progenitor cells with lentiviral vectors. To achieve transgene expression in derivative tumor infiltrating leukocytes and to try to decrease systemic toxicity, we used the stress inducible human HSP70B promoter. Functionality of the promoter was characterized in vitro using hyperthermia. Antitumor efficacy was assessed by ex vivo genetic modification of lineage-negative cells with lentiviral vectors encoding the dominant-negative mutant of the human transforming growth factor-β receptor II (TβRIIDN) driven by the HSP70B promoter, and reinfusion of cells into recipient mice. Subsequently, syngeneic GL261 glioma cells were subcutaneously injected into bone marrow-transplanted mice. As a result, a massive antitumor response was observed in mice harboring TβRIIDN under the HSP70B promoter, without the need of any external source of stress. In summary, this study shows that stem cell-based gene therapy in combination with spatial and temporal control of transgene expression in derivative tumor-infiltrating cells represents an alternative strategy for the development of novel antitumor therapies.

Gene therapy is a promising therapeutic approach to treat primary immunodeficiencies. Indeed, the clinical trial for the Wiskott–Aldrich Syndrome (WAS) that is currently ongoing at the Hannover Medical School (Germany) has recently reported the correction of all affected cell lineages of the hematopoietic system in the first treated patients. However, an extensive study of the clonal inventory of those patients reveals that LMO2, CCND2 and MDS1/EVI1 were preferentially prevalent. Moreover, a first leukemia case was observed in this study, thus reinforcing the need of developing safer vectors for gene transfer into HSC in general. Here we present a novel self-inactivating (SIN) vector for the gene therapy of WAS that combines improved safety features. We used the elongation factor 1 alpha (EFS) promoter, which has been extensively evaluated in terms of safety profile, to drive a codon-optimized human WASP cDNA. To test vector performance in a more clinically relevant setting, we transduced murine HSPC as well as human CD34+ cells and also analyzed vector efficacy in their differentiated myeloid progeny. Our results show that our novel vector generates comparable WAS protein levels and is as effective as the clinically used LTR-driven vector. Therefore, the described SIN vectors appear to be good candidates for potential use in a safer new gene therapy protocol for WAS, with decreased risk of insertional mutagenesis. Fil: Avedillo Diez, Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentina. Hannover Medical School; Alemania Fil: Zychlinski, Daniela. Hannover Medical School; Alemania Fil: Coci, Emanuele G.. Hannover Medical School; Alemania Fil: Galla, Melanie. Hannover Medical School; Alemania Fil: Modlich, Ute. Hannover Medical School; Alemania Fil: Dewey, Ricardo. Hannover Medical School; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentina Fil: Schwarzer, Adrian. Hannover Medical School; Alemania Fil: Maetzig, Tobias. Hannover Medical School; Alemania Fil: Mpofu, Nonsikelelo. Hannover Medical School; Alemania Fil: Jaeckel, Elmar. Hannover Medical School; Alemania Fil: Boztug, Kaan. Hannover Medical School; Alemania Fil: Baum, Christopher. Hannover Medical School; Alemania Fil: Klein, Christoph. Hannover Medical School; Alemania Fil: Schambach, Axel. Hannover Medical School; Alemania

Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that destroys the insulin-secreting β-cells of the pancreas. It is now possible to predict those candidates that will progress to T1D before the full onset of the disease. Prevention of uncontrollable autoimmunity against β-cells in therapies for T1D is mandatory to preserve the β-cell mass. Therefore, immunomodulatory strategies directed to inhibiting the activity of self-reactive T cell clones as well as induction of regulatory T cells would be beneficial for prevention of T1D or recurrence of β-cell autoimmunity against islet cell allografts.

Adipose tissue is an attractive source of mesenchymal stromal cells (MSCs) owing to the relative ease of obtaining large volumes with more MSC abundance compared with other sources. Increasing evidence supports the fact that trophic factors secreted by MSCs play a pivotal therapeutic role. Several strategies in regenerative medicine use MSCs, mainly exploiting their immunosuppressive effect and homing capacity to sites of damage. Transforming growth factor-b1 (TGF-b1) is a pleiotropic cytokine that, depending on the cell niche, can display either anti-inflammatory or proinflammatory effects. TGF-b1 expression increases in various tissues with damage, especially when accompanied by inflammation. Thus, we analyzed the effect of TGF-b1 on the secretion by adipose-derived mesenchymal stromal cells (ASCs) of a panel of 80 cytokines/chemokines using an antibody array. To avoid a possible effect of fetal bovine serum (FBS) on ASCs secretion, we performed our analysis by culturing cells in FBS-free conditions, only supplemented with 0.1% of bovine serum albumin. We report the cytokine profile secreted by ASCs. We also found that TGF-b1 exposure modulates 8 chemokines and 18 cytokines, including TGF-b1 and -b2, and other important cytokines involved in immunosuppression, allergic responses, and bone resorption. Fil: Rodríguez, Tania Melina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús. Instituto de Investigaciones Biotecnológicas (sede Chascomús); Argentina. Universidad Nacional de San Martín; Argentina Fil: Saldias. Alejandro. Hospital Italiano de Buenos Aires; Argentina Fil: Irigo, Marcelo. Hospital Italiano de Buenos Aires; Argentina Fil: Velasco Zamora, Jorge. Fundación Articular; Argentina Fil: Perone, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires; Argentina Fil: Dewey, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico Chascomús. Instituto de Investigaciones Biotecnológicas (sede Chascomús); Argentina. Universidad Nacional de San Martín; Argentina

Objective Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency disorder characterized by recurrent infections, autoimmunity, microthrombocytopenia, and susceptibility to malignant tumors. Compared with the conventional treatment using allogeneic bone marrow transplantation, hematopoietic stem cell gene therapy might offer more specific and less toxic therapeutic options. Methods We investigated retroviral WAS protein (WASP) gene transfer to assess functional correction and potential toxicities in human CD34 + cells from WAS patients and healthy individuals, respectively. Results WASP mRNA and protein levels were restored in CD14 + cells derived from WASP-transduced hematopoietic stem cells. Functional reconstitution in WASP-transduced myeloid cells was documented by podosome formation and FcγR-mediated phagocytosis. Importantly, overexpression of WASP in CD34 + cells from healthy donors did not cause any discernible toxic effects. Conclusions Our studies document the feasibility of WASP gene transfer into human CD34 + cells and suggest that the phenotype of WASP-deficient myeloid cells can be restored upon retroviral gene transfer.

Invasion and metastasis of certain tumors are accompanied by increased mRNA protein levels and enzymatic activity of cathepsin L. Cathepsin L has also been suggested to play a role in the proteolytic cascades associated with apoptosis. To investigate the role of cathepsin L in brain tumor invasion and apoptosis, the human glioma cell line, IPTP, was stably transfected with full-length antisense and sense cDNA of cathepsin L. Down-regulation of cathepsin L by antisense cDNA significantly impaired (up to 70%) glioma cell invasion in vitro and markedly increased glioma cell apoptosis induced by staurosporine. Compared to control and parental cell lines, antisense down-regulation of cathepsin L was associated with an earlier induction of caspase-3 activity. Up-regulation of cathepsin L activity by sense cDNA was associated with reduced apoptosis and later induction of caspase-3 activity. Moreover, down-regulation of cathepsin L lowered the expression of antiapoptotic protein Bcl-2, whereas up-regulation increased the expression of Bcl-2, indicating that cathepsin L acts upstream of caspase-3. These data show that cathepsin L is an important protein mediating the malignancy of gliomas and its inhibition may diminish their invasion and lead to increased tumor cell apoptosis by reducing apoptotic threshold.

The expression patterns of different classes of peptidases in central nervous system (CNS) tumours have been most extensively studied in astrocytomas and meningiomas. Although the two types of tumours are very different in most respects, both may invade locally into normal brain. This process of invasion includes increased synthesis and secretion of lysosomal proteolytic enzymes – cathepsins. Aspartic endopeptidase cathepsin (Cat) D levels were found to be elevated in high-grade astrocytoma and partial inhibition of glioblastoma cell invasion by anti-Cat D antibody suggests that the enzyme activity is involved in the invasion process. Several studies on cysteine endopeptidase (CP) Cat B in gliomas agreed that transcript abundance, protein level and activity of Cat B increased in high-grade astrocytoma cultures compared with low-grade astrocytoma cultures and normal brain. Moreover, in glioma biopsies Cat B levels correlated with evidence of clinical invasion and it has been demonstrated that Cat B both in tumour cells and in endothelial cells can serve as a new biological marker for prognosis in glioblastoma patients. A high level of Cat B protein was also a diagnostic marker for invasive types of meningioma, distinguishing between histomorphologically benign, but invasive meningiomas and noninvasive, so-called clear–benign meningiomas. Cat L was also significantly increased in high-grade astrocytoma compared with low-grade astrocytoma and normal brain. Specific Cat L antibodies and antisense Cat L RNA transfection significantly lowered glioblastoma cell invasion. In meningioma, Cat L was a less-significant marker of invasion than Cat B. In contrast to cathepsins, the activities of endogenous cysteine peptidase inhibitors (CPIs), including stefins, cystatins and kininogens, were significantly higher in benign and atypical meningioma cell extracts than in malignant meningioma, and low-grade compared to high-grade astrocytoma. However, very low levels of stefins A and B were found in meningioma and glioblastoma tissues. Further studies on the expression levels and balance between cysteine endopeptidases (CPs) and CPIs would improve the clinical application of cathepsins in prognosis, which would lead to more-informed therapeutic strategies.

Human embryonic kidney 293 cells contain the E1 region E1-E3 regions, in an unpackagable form. Investigation of of adenovirus type 5, and thus sustain, through transcomp- the reason for massive cell death after cotransfection led lementation, the production of recombinant E1-deleted us to determine that 293 cells express the FasL receptor, adenovirus vectors. During attempts to produce recombi- Fas-Apo1 (CD95), and respond with apoptosis to the nant adenovirus expressing the apoptosis-inducing mol- cross-linking of Fas-Apo1 with either IgM monoclonal antiecule Fas ligand (FasL) under the control of a very strong bodies or FasL. Therefore, we decided to generate adenotruncated major immediate‐early human cytomegalovirus viral vectors expressing FasL under the control of tissue(MIEhCMV) promoter, we discovered that 293 cells were specific and/or -inducible promoter elements. Our findings not surviving the initial cotransfection with a shuttle plasmid can explain difficulties several groups have had in generatencoding the mouse FasL; and pJM17, a plasmid contain- ing recombinant adenoviral vectors expressing FasL using ing the genome of adenovirus type 5 with deletions in the 293 cells, as well as the lower titres reported.

The genus Tospovirus was thought to be composed only of the tomato spotted wilt virus (TSWV), but now at least four Tospovirus species have been proposed based on serological and molecular data. A classification of tospoviruses has been proposed taking into account global similarities of the N gene and N protein sequences of 7 isolates of Tospovirus. Because phylogenetic analyses based on global similarities can lead to classifications which do not mirror the genealogy of the group, we have employed a cladistic analysis using parsimony of this genus with RNA sequences of 450 nucleotides of the N gene from 14 new Argentinean isolates and 4 previously described isolates. Representatives of the Bunyaviridae family, Rift Valley Fever Virus (Phlebovirus) and Bunyamwera (Bunyavirus), were used as the outgroup in separate analyses.

Tomato spotted wilt is a serious disease that affects several economically important crops. From the epidemiological point of view and for the development of a successful plan for transgenic resistance plants, the four known Tospovirus species must be discriminated at the molecular level. A RT-PCR assay using primers complementary to the N gene was used to detect and differentiate fourteen Argentinian isolates of Tospovirus from different crops and geographical areas. Extracts were reverse transcribed using a thermo-resistant reverse transcriptase and PCR reactions were performed for 30 min in a capillar thermo-cycler. The products were digested with restriction enzymes and three of the four described species were identified. Additionally, the results were confirmed by DAS-ELISA. The method described here is rapid and reliable.

Type 1 diabetes mellitus (T1DM) results from death of insulin-secreting b cells mediated by self-immune cells, and the consequent inability of the body to maintain insulin levels for appropriate glucose homeostasis. Probably initiated by environmental factors, this disease takes place in genetically predisposed individuals. Given the autoimmune nature of T1DM, therapeutics targeting immune cells involved in disease progress have been explored over the last decade. Several high-cost trials have been attempted to prevent and/or reverse T1DM. Although a definitive solution to cure T1DM is not yet available, a large amount of information about its nature and development has contributed greatly to both the improvement of patient?s health care and design of new treatments. In this study, we discuss the role of different types of immune cells involved in T1DM pathogenesis and their therapeutic potential as targets and/or modified tools to treat patients. Recently, encouraging results and new approaches to sustain remnant b cell mass and to increase b cell proliferation by different cell based means have emerged. Results coming from ongoing clinical trials employing cell therapy designed to arrest T1DM will probably proliferate in the next few years. Strategies under consideration include infusion of several types of stem cells, dendritic cells and regulatory T cells, either manipulated genetically ex vivo or non-manipulated. Their use in combination approaches is another therapeutic alternative. Cell-based interventions, without undesirable side effects, directed to block the uncontrollable autoimmune response may become a clinical reality in the next few years for the treatment of patients with T1DM. Fil: Barcala Tabarrozzi, Andrés Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Castro, Carla Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Dewey, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Sogayar, M. C.. Universidade de Sao Paulo; Brasil Fil: Labriola, L.. Universidade de Sao Paulo; Brasil Fil: Perone, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina

This paper describes the characterization of a Tospovirus isolate (M316) from Mendoza, Argentina. The N gene was cloned and sequenced. The sequence obtained was compared with the N gene sequences of other tospoviruses. The percentages of the nucleotide homology and amino acid similarity showed that this isolate may be considered a member of the species groundnut ringspot virus (GRSV). The conclusion drawn from the molecular studies was confirmed by DAS-ELISA and western blotting. This is the first report of GRSV in Argentina, previously described for a South African (SA-05) and Brazilian (BR-08) isolates.

The Wiskott-Aldrich syndrome (WAS) is an X-linked recessive primary immunodeficiency disorder associated with thrombocytopenia, eczema, and autoimmunity. We treated two patients who had this disorder with a transfusion of autologous, genetically modified hematopoietic stem cells (HSC). We found sustained expression of WAS protein expression in HSC, lymphoid and myeloid cells, and platelets after gene therapy. T and B cells, natural killer (NK) cells, and monocytes were functionally corrected. After treatment, the patients' clinical condition markedly improved, with resolution of hemorrhagic diathesis, eczema, autoimmunity, and predisposition to severe infection. Comprehensive insertion-site analysis showed vector integration that targeted multiple genes controlling growth and immunologic responses in a persistently polyclonal hematopoiesis. (Funded by Deutsche Forschungsgemeinschaft and others; German Clinical Trials Register number, DRKS00000330.).

Wiskott-Aldrich syndrome (WAS) is a complex primary immunodeficiency disorder associated with microthrombocytopenia, autoinnmunity and susceptibility to malignant lymphoma. At the molecular level, this rare disorder is caused by mutations in the gene encoding the Wiskott-Aldrich syndrome protein (WASP). WASP is a cytosolic adaptor protein mediating the rearrangement of the actin cytoskeleton upon surface receptor signaling. Allogenic hematopoietic stem cell (HSC) transplantation represents a curative approach but remains problematic in light of severe risks and side effects. Recently, HSC gene therapy has emerged as an alternative treatment option. Cumulative preclinical data obtained from WASP-deficient murine models and human cells indicate a marked improvement of the impaired cellular and immunological phenotypes associated with WASP deficiency. The first clinical trial is currently being conducted to assess the feasibility, toxicity, and potential therapeutic benefit of transplanting autologous WASP-reconstituted hematopoietic stem cells.

Lysosome-related organelles have versatile functions, including protein and lipid degradation, signal transduction and protein secretion. The molecular elucidation of rare congenital diseases affecting endosomal-lysosomal biogenesis has given insights into physiological functions of the innate and adaptive immune system. Here, we describe a previously unknown human primary immunodeficiency disorder and provide evidence that the endosomal adaptor protein p14, previously characterized as confining mitogen-activated protein kinase (MAPK) signaling to late endosomes, is crucial for the function of neutrophils, B cells, cytotoxic T cells and melanocytes. Combining genetic linkage studies and transcriptional profiling analysis, we identified a homozygous point mutation in the 3' untranslated region (UTR) of p14 (also known as MAPBPIP), resulting in decreased protein expression. In p14-deficient cells, the distribution of late endosomes was severely perturbed, suggesting a previously unknown role for p14 in endosomal biogenesis. These findings have implications for understanding endosomal membrane dynamics, compartmentalization of cell signal cascades, and their role in immunity.

The expression patterns of different classes of peptidases in central nervous system (CNS) tumours have been most extensively studied in astrocytomas and meningiomas. Although the two types of tumours are very different in most respects, both may invade locally into normal brain. This process of invasion includes increased synthesis and secretion of lysosomal proteolytic enzymes - cathepsins. Aspartic endopeptidase cathepsin (Cat) D levels were found to be elevated in high-grade astrocytoma and partial inhibition of glioblastoma cell invasion by anti-Cat D antibody suggests that the enzyme activity is involved in the invasion process. Several studies on cysteine endopeptidase (CP) Cat B in gliomas agreed that transcript abundance, protein level and activity of Cat B increased in high-grade astrocytoma cultures compared with low-grade astrocytoma cultures and normal brain. Moreover, in glioma biopsies Cat B levels correlated with evidence of clinical invasion and it has been demonstrated that Cat B both in tumour cells and in endothelial cells can serve as a new biological marker for prognosis in glioblastoma patients. A high level of Cat B protein was also a diagnostic marker for invasive types of meningioma, distinguishing between histomorphologically benign, but invasive meningiomas and noninvasive, so-called clear-benign meningiomas. Cat L was also significantly increased in high-grade astrocytoma compared with low-grade astrocytoma and normal brain. Specific Cat L antibodies and antisense Cat L RNA transfection significantly lowered glioblastoma cell invasion. In meningioma, Cat L was a less-significant marker of invasion than Cat B. In contrast to cathepsins, the activities of endogenous cysteine peptidase inhibitors (CPIs), including stefins, cystatins and kininogens, were significantly higher in benign and atypical meningioma cell extracts than in malignant meningioma, and low-grade compared to high-grade astrocytoma. However, very low levels of stefins A and B were found in meningioma and glioblastoma tissues. Further studies on the expression levels and balance between cysteine endopeptidases (CPs) and CPIs would improve the clinical application of cathepsins in prognosis, which would lead to more-informed therapeutic strategies.

Herpes simplex virus type 1-thymidine kinase (HSV1-TK) in combination with ganciclovir is an efficient and widely used strategy in brain tumour gene therapy. Recently, we have shown effective inhibition of glioma growth in a syngeneic rat model using recombinant adenoviruses expressing the full-length HSV1-TK and an N-terminus truncated variant, HSV1-DeltaTK in the presence of ganciclovir. We also showed active chronic brain inflammation in the long-term survivors (3 months) treated with HSV1-TK plus GCV. Furthermore, our results indicated loss of myelinated fibres, oedema and indices of ongoing axonal degeneration. In this study, we assessed the cytotoxicity of both HSV1-TK variants in the presence or absence of ganciclovir, in primary cultures of neurones and glia, and in the rat brain in vivo. Our results indicate that, at viral doses where tumour cells are sensitive to the enzyme/prodrug system, (1) there is no major cytotoxicity for either neurones or glial cells grown in primary cultures, (2) on its own the full-length HSV1-TK is more cytotoxic than its truncated version HSV1-DeltaTK for a population of non-neuronal and non-glial cells within neocortical primary cultures, and (3) in vivo, when delivered into the striatum, RAds encoding HSV1-TK are more cytotoxic than RAds encoding HSV1-DeltaTK, after administration of ganciclovir. The effectiveness of HSV1-DeltaTK in preventing brain tumour growth in vivo, combined with its reduced cytotoxicity, both in vivo and in primary cultures of CNS cells, could represent an advantage for treatment of brain tumours using gene therapy.

We tested the hypothesis that gene transfer using recombinant adenovirus vectors (RAds) expressing herpes simplex virus type 1 thymidine kinase (HSV1-TK) might offer an alternative therapeutic approach for the treatment of pituitary prolactinomas that do not respond to classical treatment strategies. HSV1-TK converts the prodrug ganciclovir (GCV) to GCV monophosphate, which is in turn further phosphorylated by cellular kinases to GCV triphosphate, which is toxic to proliferating cells. One attractive feature of this system is the bystander effect, whereby untransduced cells are also killed. Our results show that RAd/HSV1-TK in the presence of GCV is nontoxic for the normal anterior pituitary (AP) gland in vitro, but causes cell death in the pituitary tumor cell lines GH3, a PRL/GH-secreting cell line, and AtT20, a corticotrophic cell line. We have used sulpiride- and oestrogen-induced lactotroph hyperplasia within the rat AP gland as an in vivo animal model. Intrapituitary infection of rats bearing oestrogen-induced lactotroph hyperplasia, with RAd/HSV1-TK and subsequent treatment with GCV, decreases plasma PRL levels and reduces the mass of the pituitary gland. More so, there were no deleterious effects on circulating levels of other AP hormones, suggesting that the treatment was nontoxic to the AP gland in situ. In summary, our results show that suicide gene therapy using the HSV1-TK transgene could be further developed as a useful treatment to complement current therapies for prolactinomas.

The long-term consequences of adenovirus-mediated conditional cytotoxic gene therapy for gliomas remain uncharacterized. We report here detection of active brain inflammation 3 months after successful inhibition of syngeneic glioma growth. The inflammatory infiltrate consisted of activated macrophages/microglia and astrocytes, and T lymphocytes positive for leucosyalin, CD3 and CD8, and included secondary demyelination. We detected strong widespread herpes simplex virus 1 thymidine kinase immunoreactivity and vector genomes throughout large areas of the brain. Thus, patient evaluation and the design of clinical trials in ongoing and future gene therapy for brain glioblastoma must address not only tumor-killing efficiency, but also long-term active brain inflammation, loss of myelin fibers and persistent transgene expression.

BLAD (Bovine Leukocyte Adhesion Deficiency) and DUMPS (Deficiency of Uridine Monophosphate Synthase) are monogenic autosomal, recessive inherited diseases of Holstein cattle. Single nucleotide changes (point mutations) responsible for the genetic disorders were detected by polymerase chain reaction coupled with restriction fragment length polymorphism assays (PCR-RFLP). Using oligonucleotide primers, DNA fragments of predicted sizes were amplified, and the products' specificity was assessed by nucleotide sequencing. Mutations were detected in DNA samples from bovine blood and semen by the presence or absence of restriction sites within the PCR amplification products (Taq I, Hae III for BLAD, Ava I for DUMPS). The test included 104 bulls and 950 cows of Argentinean Holstein breed. Defective alleles frequencies were as follows: 2.88% BLAD in bulls used in artificial insemination, 1.79% in cows; 0.96% DUMPS in bulls and 0.11% in cows.

Author(s): Semorile, L.; Dewey, R.; Garcia, M. L.; Dal Bo, E.; Ghiringhelli, P. D.; Romanowski, V.; Grau, O.

Abstract 5 Wiskott Aldrich Syndrome is a life-threatening immune-disorder characterized by bleeding secondary to microthrombocytopenia, immunodeficiency, autoimmunity, and susceptibility to lymphoma. A clinical gene therapy protocol using a GALV pseudotyped MLV-derived retroviral vector was developed at Hannover Medical School. We here present an analysis of ten patients treated in this trial between 2006 and 2009. All patients had evidence of engraftment of WASP-positive hematopoietic progenitor cells except for one patient in whom an insufficient number of CD34+ cells could be harvested. WASP expression was determined in myeloid and lymphoid cells as well as in CD34+ hematopoietic progenitor cells using Western Blot and FACS analysis, respectively. While the percentage of WASP-positive myeloid cells was relatively stable over time (range 10 to 60%), a marked increase over time in the percentage of WASP-positive T lymphocytes and NK cells was observed, resulting in more than 80% of WASP-positive lymphoid cells 12 months after gene therapy. Early after gene therapy, an increase in thrombocyte counts was observed in all patients. Furthermore, the majority of peripheral thrombocytes showed evidence of WASP expression, detectable as early as 3 months after gene therapy. Functional immune reconstitution was documented in dendritic cells (podosome formation), T cells (proliferation in response to CD3-signaling), and NK cells (formation of immunological synapse and NK cell killing activity). TCR Vb spectratyping analyses showed in improvement of receptor skewing upon gene therapy in some patients. A clinical benefit was notable in all patients with the exception of the patients with insufficient engraftment of genetically corrected progenitor cells: eczema, bleeding diathesis and immunodeficiency resolved. Strikingly, the various autoimmune phenomena which the patients in this trial had shown prior to gene therapy resolved when the majority of T lymphocytes were positive for WASP expression, and a particular advantage of WASP-positive regulatory T lymphocytes (Tregs) could be observed at this point, suggesting a crucial role in WASP reconstitution in Tregs for autoimmnity resolution. Repetitive bone marrow examinations did not reveal morphological or cytogenetic alterations. Comprehensive insertion site analysis using 454 pyrosequencing demonstrated vector integration that targeted multiple genes controlling growth, development and immunological responses in a persistently polyclonal hematopoiesis. In sum, hematopoietic stem cell gene therapy for Wiskott-Aldrich Syndrome is feasible and effective at correcting the various cellular defects implicated in this disease. Our trial provides the first proof-of-principle for gene therapy in Wiskott-Aldrich syndrome and provides evidence that gene therapy may be effective at correcting disorders involving autoimmunity and/or platelets. Prospective monitoring is used in this trial to determine the long-term efficacy and safety profile of this experimental therapeutic approach in Wiskott-Aldrich syndrome. Disclosures: No relevant conflicts of interest to declare.

In an attempt to design novel therapeutic strategies against solid tumors, we hypothesized that spatial and temporal control of transgene expression may allow for the delivery of immunomodulatory molecules at the site of tumor. Here, we assess the potential of the HSP70b promotor to control lentivirus-mediated gene expression in tumor-infiltrating hematopoietic cells. We generated a series of lentiviral vectors and characterized transgene expression in vitro and in vivo. Up to 20fold induction of GFP expression was seen when lentivirus-transduced cells were heated to 43°C in vitro. Only minimal leakiness was seen at 37°C. Next, we analyzed HSP-driven GFP expression in hematopoietic cells upon transplantation of lentivirus-transduced hematopoietic stem cells, using constitutively active promotors and empty vectors as controls. Mice were inoculated with the glioma cell line GL261 and GFP expression was assessed in various organs as well as in tumor-infiltrating hematopoietic cells. Interestingly, HSP70-driven transgene expression was 10–15fold higher in tumor-infiltrating cells when compared to spleen cells, suggesting that the HSP70b promoter was active in the tumor microenvironment. To assess whether confined expression of a dominant negative TGF-β-receptor within the tumor microenvironment would induce anti-tumor immunity, we transplanted mice with hematopoietic stem cells transduced with TGF-β-DNR and injected GL261 cells subcutaneously. The tumor volume was decreased up to 40 fold in mice expressing HSP70b-TGF-β-DNR, comparable to mice transplanted with hematopoietic stem cells that constitutively express TGF-β-DNR. Functional studies suggest a role for perforin, IFN-α and Granzyme B in this TNF-β-DNR-dependent immunomodulatory circuit. In summary, HSP70b-mediated transgene expression in hematopoietic cells may provide a novel experimental strategy for controlled release of immunmodulatory molecules to induce anti-tumor therapies.

[Graphic][1] Wiskott Aldrich Syndrome (WAS) is a life-threatening primary immunodeficiency disorder characterized by susceptibility to infections, hemorrhage and malignancies. We here report the clinical, immunological, and molecular results of ten patients treated with transfusion of autologous genetically corrected hematopoietic stem cells between 2006 and 2009. After hematopoietic stem cell gene therapy with a gamma-retroviral vector, we observed phenotypical and functional reconstitution of lymphoid, myeloid cell lines and platelet numbers in 9/10 patients. Of note, patients had sustained correction of T-cell proliferation, immunological synapse formation and NK-cell mediated lysis, capacity to generate specific antibodies, and platelet production and size. All nine patients with sustained stem cell engraftment had marked clinical improvement with respect to infections, bleeding, and autoimmunity. Comprehensive analysis of retroviral insertions sites revealed a polyclonal hematopoiesis with more than 120.000 recurring loci. However, 5/10 of patients developed T-ALL (mean 1054.2d post GT; range 488-1813d post GT), each associated with a retroviral insertion in close proximity to the LMO2 locus. In 3/5 of patients with T-ALL (treatment according to AEIOP 2009 protocol) allogeneic HSCT due to poor initial response, minimal residual disease relapse, or cytological relapse was indicated. Further, one patient developed MDS like bone marrow changes and consecutively AML (1165d post GT), HSCT was performed in remission. Retrospectively, MDS1 clonal contribution to insertion sites showed a slow increase over the period of 22 month in this patient. GT has proven to revert the cellular and clinical phenotype of WAS but remains associated with considerable risk for insertional mutagenesis. Refining gene therapy strategies is an important goal for patients with WAS. Disclosures: Naundorf: EUFETS GmbH: Employment. Kuhlcke: EUFETS GmbH: Employment. [1]: /embed/inline-graphic-2.gif

Gene therapy using Fas ligand (FasL) for treatment of tumours and protection of transplant rejection is hampered because of the systemic toxicity of FasL. In the present study, recombinant replication-defective adenovirus vectors (RAds) encoding FasL under the control of either the neuronal-specific neuronal-specific enolase (NSE) promoter or the astrocyte-specific glial fibrillary acidic protein (GFAP) promoter have been constructed. The cell type-specific expression of FasL in both neurons and glial cells in primary cultures, and in neuronal and glial cell lines is demonstrated. Furthermore, transgene expression driven by the neuronal and glial promoter was not detected in fibroblastic or epithelial cell lines. Expression of FasL driven by a major immediate early human cytomegalovirus promoter (MIEhCMV) was, however, achieved in all cells tested. As a final test of the stringency of transgene-specific expression, the RAds were injected directly into the bloodstream of mice. The RAds encoding FasL under the control of the non-cell type-specific MIEhCMV promoter induced acute generalized liver haemorrhage with hepatocyte apoptosis, while the RAds containing the NSE or GFAP promoter sequences were completely non-toxic. This demonstrates the specificity of transgene expression, enhanced safety during systemic administration, and tightly regulated control of transgene expression of highly cytotoxic gene products, encoded within transcriptionally targeted RAds.