DPP-4 Inhibition Leads to Decreased Pancreatic Inflammatory Profile and Increased Frequency of Regulatory T Cells in Experimental Type 1 Diabetes.

Sitagliptin is a dipeptidyl peptidase-4 inhibitor (iDPP-4), which has been used for type 2 diabetes treatment. Recently, iDPP-4 has been described as a promising treatment of type 1 diabetes (T1D) but is still necessary to evaluate immune effects of sitagliptin. C57BL/6 mice were induced by multiple low doses of streptozotocin. Diabetes incidence, insulin, glucagon, glucagon-like peptide-1 (GLP-1) serum levels, and inflammatory cytokine levels were quantified in pancreas homogenate after 30 and 90 days of treatment. In addition, frequencies of inflammatory and regulatory T cell subsets were determined in the spleen and in the pancreatic lymph nodes. iDPP-4 decreased blood glucose level while increased GLP-1 and insulin levels. After long-term treatment, treated diabetic mice presented decreased frequency of CD4+CD26+ T cells and increased percentage of CD4+CD25hiFoxp3+ T cells in the spleen. Besides, pancreatic lymph nodes from diabetic mice treated with iDPP-4 presented lower percentage of CD11b+ cells and decreased levels of inflammatory cytokines in the pancreas. Treatment of type 1 diabetic mice with iDPP-4 improved metabolic control, decreased inflammatory profile in the pancreatic microenvironment, and increased systemic regulatory T cell frequency. Therefore, we suggest the long-term use of sitagliptin as a feasible and effective therapy for T1D.

Immunological Balance Is Associated with Clinical Outcome after Autologous Hematopoietic Stem Cell Transplantation in Type 1 Diabetes.

Autologous hematopoietic stem cell transplantation (AHSCT) increases C-peptide levels and induces insulin independence in patients with type 1 diabetes. This study aimed to investigate how clinical outcomes may associate with the immunological status, especially concerning the balance between immunoregulation and autoreactivity. Twenty-one type 1 diabetes patients were monitored after AHSCT and assessed every 6 months for duration of insulin independence, C-peptide levels, frequencies of islet-specific autoreactive CD8+ T cells (CTL), regulatory lymphocyte subsets, thymic function, and T-cell repertoire diversity. In median follow-up of 78 (range 15-106) months, all patients became insulin-independent, resuming insulin after median of 43 (range 6-100) months. Patients were retrospectively divided into short- or prolonged-remission groups, according to duration of insulin independence. For the entire follow-up, CD3+CD4+ T-cell numbers remained lower than baseline in both groups, whereas CD3+CD8+ T-cell levels did not change, resulting in a CD4/CD8 ratio inversion. Memory CTL comprehended most of T cells detected on long-term follow-up of patients after AHSCT. B cells reconstituted to baseline levels at 2-3 months post-AHSCT in both patient groups. In the prolonged-remission-group, baseline islet-specific T-cell autoreactivity persisted after transplantation, but regulatory T cell counts increased. Patients with lower frequencies of autoreactive islet-specific T cells remained insulin-free longer and presented greater C-peptide levels than those with lower frequencies of these cells. Therefore, immune monitoring identified a subgroup of patients with superior clinical outcome of AHSCT. Our study shows that improved immunoregulation may balance autoreactivity endorsing better metabolic outcomes in patients with lower frequencies of islet-specific T cells. Development of new strategies of AHSCT is necessary to increase frequency and function of T and B regulatory cells and decrease efficiently autoreactive islet-specific T and B memory cells in type 1 diabetes patients undergoing transplantation.

Transcriptional profiling reveals intrinsic mRNA alterations in multipotent mesenchymal stromal cells isolated from bone marrow of newly-diagnosed type 1 diabetes patients.

BACKGROUND: Bone marrow multipotent mesenchymal stromal cells (MSCs) are a diverse subset of precursors that contribute to the homeostasis of the hematopoietic niche. MSCs can be isolated and expanded in vitro and have unique immunomodulatory and regenerative properties that make them attractive for the treatment of autoimmune diseases, including type 1 diabetes (T1D). Whether autologous or allogeneic MSCs are more suitable for therapeutic purposes has not yet been established. While autologous MSCs may present abnormal function, allogeneic cells may be recognized and rejected by the host immune system. Thus, studies that investigate biological characteristics of MSCs isolated from T1D patients are essential to guide future clinical applications. METHODS: Bone marrow-derived MSCs from recently diagnosed type 1 diabetes patients (T1D-MSCs) were compared with those from healthy individuals (C-MSCs) for morphological and immunophenotypic characteristics and for differentiation potential. Bioinformatics approaches allowed us to match absolute and differential gene expression of several adhesion molecules, immune mediators, growth factors, and their receptors involved with hematopoietic support and immunomodulatory properties of MSCs. Finally, the differentially expressed genes were collated for functional pathway enrichment analysis. RESULTS: T1D-MSCs and C-MSCs were similar for morphology, immunophenotype, and differentiation potential. Our absolute gene expression results supported previous literature reports, while also detecting new potential molecules related to bone marrow-derived MSC functions. T1D-MSCs showed intrinsic abnormalities in mRNA expression, including the immunomodulatory molecules VCAM-1, CXCL12, HGF, and CCL2. Pathway analyses revealed activation of sympathetic nervous system and JAK STAT signaling in T1D-MSCs. CONCLUSIONS: Collectively, our results indicate that MSCs isolated from T1D patients present intrinsic transcriptional alterations that may affect their therapeutic potential. However, the implications of these abnormalities in T1D development as well as in the therapeutic efficacy of autologous MSCs require further investigation.

Immunological correlates of favorable long-term clinical outcome in multiple sclerosis patients after autologous hematopoietic stem cell transplantation.

High dose immunosuppression followed by autologous hematopoietic stem cell transplantation (AHSCT) induces prolonged clinical remission in multiple sclerosis (MS) patients. However, how patient immune profiles are associated with clinical outcomes has not yet been completely elucidated. In this study, 37 MS patients were assessed for neurological outcomes, thymic function and long-term immune reconstitution after AHSCT. Patients were followed for a mean (SD) of 68.5 (13.9) months post-transplantation and were retrospectively clustered into progression- and non-progression groups, based on Expanded Disease Status Scale (EDSS) outcomes at last visit. After AHSCT, both patient groups presented increased regulatory T-cell subset counts, early expansion of central- and effector-memory CD8(+)T-cells and late thymic reactivation. However, the non-progression group presented early expansion of PD-1(+)CD8(+)T-cells and of PD-1-expressing CD19(+) B-cells. Here, we suggest that along with increased numbers of regulatory T-cell subsets, PD-1 inhibitory signaling is one possible immunoregulatory mechanism by which AHSCT restores immune tolerance in MS patients.

Multipotent mesenchymal stromal cells from patients with newly diagnosed type 1 diabetes mellitus exhibit preserved in vitro and in vivo immunomodulatory properties.

BACKGROUND: Type 1 diabetes mellitus (T1D) is characterized by autoimmune responses resulting in destruction of insulin-producing pancreatic beta cells. Multipotent mesenchymal stromal cells (MSCs) exhibit immunomodulatory potential, migratory capacity to injured areas and may contribute to tissue regeneration by the secretion of bioactive factors. Therefore, MSCs are considered as a promising approach to treat patients with different autoimmune diseases (AID), including T1D patients. Phenotypical and functional alterations have been reported in MSCs derived from patients with different AID. However, little is known about the properties of MSCs derived from patients with T1D. Since autoimmunity and the diabetic microenvironment may affect the biology of MSCs, it becomes important to investigate whether these cells are suitable for autologous transplantation. Thus, the aim of the present study was to evaluate the in vitro properties and the in vivo therapeutic efficacy of MSCs isolated from bone marrow of newly diagnosed T1D patients (T1D-MSCs) and to compare them with MSCs from healthy individuals (C-MSCs). METHODS: T1D-MSCs and C-MSCs were isolated and cultured until third passage. Then, morphology, cell diameter, expression of surface markers, differentiation potential, global microarray analyses and immunosuppressive capacity were in vitro analyzed. T1D-MSCs and C-MSCs therapeutic potential were evaluated using a murine experimental model of streptozotocin (STZ)-induced diabetes. RESULTS: T1D-MSCs and C-MSCs presented similar morphology, immunophenotype, differentiation potential, gene expression of immunomodulatory molecules and in vitro immunosuppressive capacity. When administered into diabetic mice, both T1D-MSCs and C-MSCs were able to reverse hyperglycemia, improve beta cell function and modulate pancreatic cytokine levels. CONCLUSIONS: Thus, bone marrow MSCs isolated from T1D patients recently after diagnosis are not phenotypically or functionally impaired by harmful inflammatory and metabolic diabetic conditions. Our results provide support for the use of autologous MSCs for treatment of newly diagnosed T1D patients.

Xenogeneic Mesenchymal Stromal Cells Improve Wound Healing and Modulate the Immune Response in an Extensive Burn Model.

Major skin burns are difficult to treat. Patients often require special care and long-term hospitalization. Besides specific complications associated with the wounds themselves, there may be impairment of the immune system and of other organs. Mesenchymal stromal cells (MSCs) are a recent therapeutic alternative to treat burns, mainly aiming to accelerate the healing process. Several MSC properties favor their use as therapeutic approach, as they promote angiogenesis, stimulate regeneration, and enhance the immunoregulatory function. Moreover, since patients with extensive burns require urgent treatment and because the expansion of autologous MSCs is a time-consuming process, in this present study we chose to evaluate the therapeutic potential of xenogeneic MSCs in the treatment of severe burns in rats. MSCs were isolated from mouse bone marrow, expanded in vitro, and intradermally injected in the periphery of burn wounds. MSC-treated rats presented higher survival rates (76.19%) than control animals treated with PBS (60.86%, p < 0.05). In addition, 60 days after the thermal injury, the MSC-treated group showed larger proportion of healed areas within the burn wounds (90.81 ± 5.05%) than the PBS-treated group (76.11 ± 3.46%, p = 0.03). We also observed that CD4(+) and CD8(+) T cells in spleens and in damaged skin, as well as the percentage of neutrophils in the burned area, were modulated by MSC treatment. Plasma cytokine (TGF-ß, IL-10, IL-6, and CINC-1) levels were also altered in the MSC-treated rats, when compared to controls. Number of injected GFP(+) MSCs progressively decreased over time, and 60 days after injection, few MSCs were still detected in the skin of treated animals. This study demonstrates the therapeutic effectiveness of intradermal application of MSCs in a rat model of deep burns, providing basis for future regenerative therapies in patients suffering from deep burn injuries.

Therapeutic efficacy and biodistribution of allogeneic mesenchymal stem cells delivered by intrasplenic and intrapancreatic routes in streptozotocin-induced diabetic mice.

INTRODUCTION: Mesenchymal stromal/stem cells (MSCs) are multipotent cells that have the ability to express and secrete a wide range of immunomodulatory molecules, cytokines, growth factors and antiapoptotic proteins. MSCs modulate both innate and adaptive immune responses making them potential candidates for the treatment of patients with type 1 diabetes mellitus (T1D). However, one problem frequently associated with the systemic MSCs administration is the entrapment of the cells mainly in the lungs. In this sense, trying to avoid the lung barrier, the purpose of this study was to evaluate the long-term therapeutic efficacy and biodistribution of allogeneic adipose tissue-derived MSCs (ADMSCs) injected via two different delivery routes (intrasplenic/I.Sp and intrapancreatic/I.Pc) in a murine model of diabetes induced by streptozotocin (STZ). METHODS: Experimental diabetes was induced in C57BL/6 male mice by multiple low-doses of STZ. MSCs were isolated from adipose tissue (ADMSCs) of Balb/c mice. A single dose of 1x10(6) ADMSCs was microinjected into the spleen or into the pancreas of diabetic mice. Control group received injection of PBS by I.Sp or I.Pc delivery routes. Glycemia, peripheral glucose response, insulin-producing ß cell mass, regulatory T cell population, cytokine profile and cell biodistribution were evaluated after ADMSCs/PBS administration. RESULTS: ADMSCs injected by both delivery routes were able to decrease blood glucose levels and improve glucose tolerance in diabetic mice. ADMSCs injected by I.Sp route reverted hyperglycemia in 70% of diabetic treated mice, stimulating insulin production by pancreatic ß cells. Using the I.Pc delivery route, 42% of ADMSCs-treated mice responded to the therapy. Regulatory T cell population remained unchanged after ADMSCs administration but pancreatic TGF-ß levels were increased in ADMSCs/I.Sp-treated mice. ADMSCs administrated by I.Sp route were retained in the spleen and in the liver and ADMSCs injected by I.Pc route remained in the pancreas. However, ADMSCs injected by these delivery routes remained only few days in the recipients. CONCLUSION: Considering the potential role of MSCs in the treatment of several disorders, this study reports alternative delivery routes that circumvent cell entrapment into the lungs promoting beneficial therapeutic responses in ADMSCs-treated diabetic mice.

Metabolic and pancreatic effects of bone marrow mesenchymal stem cells transplantation in mice fed high-fat diet.

The purpose of this study was to investigate the effects of multiple infusions of allogeneic MSCs on glucose homeostasis and morphometry of pancreatic islets in high- fat diet (HFD) fed mice. Swiss mice were fed standard diet (C group) or HFD (HFD group). After 8 weeks, animals of HFD group received sterile phosphate-buffered saline infusions (HFD-PBS) or four infusions of MSCs one week apart (HFD-MSCs). Fasting glycemia (FG) was determined weekly and glucose (GTT) and insulin (ITT) tolerance tests were performed 4, 8, 12, and 16 weeks after the infusions of MSCs. The MSCs transplanted mice were classified as responder (FG < 180 mg/dL, 72.2% of transplanted mice) or non-responder (FG > 180mg/dL, 28.8%) Seven weeks after MSCs infusions, FG decreased in HFD-MSCs responder mice compared with the HFD-PBS group. Sixteen weeks post MSCs infusions, GTT and ITT areas under the curve (AUC) decreased in HFD-MSCs responder mice compared to HFD-PBS group. Serum insulin concentration was higher in HFD-PBS group than in control animals and was not different compared with the other groups. The relative volume of α-cells was significantly smaller in HFD-PBS group than in C group and significantly higher in HFD-MSCs-NR than in HFD-PBS and HFD-MSCs-R groups. Cell apoptosis in the islets was higher in HFD-PBS group than in C group, and lower in HFD-MSCs responder mice than in HFD-PBS group and non-responder animals. The results demonstrate the ability of multiple infusions of MSCs to promote prolonged decrease in hyperglycemia and apoptosis in pancreatic islets and increase in insulin sensitivity in HFD fed mice.

Autologous haematopoietic stem cell transplantation reduces abnormalities in the expression of immune genes in multiple sclerosis.

Autologous haematopoietic stem-cell transplantation (AHSCT) has been experimented as a treatment in patients affected by severe forms of multiple sclerosis (MS) who failed to respond to standard immunotherapy. The rationale of AHSCT is to 'reboot' the immune system and reconstitute a new adaptive immunity. The aim of our study was to identify, through a robust and unbiased transcriptomic analysis, any changes of gene expression in T-cells potentially underlying the treatment effect in patients who underwent non-myeloablative AHSCT for treatment of MS. We evaluated by microarray DNA-chip technology the gene expression of peripheral CD4+ and CD8+ T-cell subsets sorted from patients with MS patients before AHSCT, at 6 months, 1 year and 2 years after AHSCT and from healthy control subjects. Hierarchical clustering analysis revealed that reconstituted CD8+ T-cells of MS patients at 2 years post-transplantation, aggregated together with healthy controls, suggesting a normalization of gene expression in CD8+ cells post-therapy. When we compared the gene expression in MS patients before and after therapy, we detected a large number of differentially expressed genes (DEG) in both CD8+ and CD4+ T-cell subsets at all time points after transplantation. We catalogued the biological function of DEG and we selected 27 genes known to be involved in immune function for accurate quantification of gene expression by real-time PCR. The analysis confirmed and extended with quantitative data, a number of significant changes in both the CD4+ and CD8+ T-cells subsets from MS post-transplant. Notably, CD8+ T-cells revealed more extensive changes in the expression of genes involved in effector immune responses.

Influence of fludarabine on the pharmacokinetics of oral busulfan during pretransplant conditioning for hematopoietic stem cell transplantation.

This study evaluated the influence of fludarabine on the pharmacokinetics of busulfan administered orally to patients receiving a conditioning regimen for hematopoietic allogeneic stem cell transplantation (HSCT). Twenty-six patients treated with oral busulfan (1 mg/kg/6 h for 4 days) were divided into two groups according to the concomitant administration of fludarabine (n = 11; 30 mg/m(2) for 5 days) or subsequent administration of cyclophosphamide (n = 15; 60 mg/kg for 2 days). Serial blood samples were collected on Day 4 of busulfan administration. Plasma busulfan concentrations were determined by HPLC-UV and the pharmacokinetic parameters were calculated using the WinNonlin program. Patients concomitantly treated with fludarabine showed reduced apparent clearance of busulfan (110.5 mL/h/kg vs. 157.4 mL/h/kg) and higher AUC0-6 (area under the plasma concentrations vs. time curve) than patients subsequently treated with cyclophosphamide (7.9 µg h/mL vs. 5.7 µg h/mL). No association was observed between busulfan AUC0-6 and clinical evolution of the patients. Although plasma busulfan concentrations were higher in patients receiving concomitant fludarabine, myelosuppression-related toxicity was less frequent than in patients treated with busulfan and cyclophosphamide. The results suggest that patients treated with fludarabine should receive 30% lower busulfan doses during conditioning protocols for HSCT.

Cardiac involvement and treatment-related mortality after non-myeloablative haemopoietic stem-cell transplantation with unselected autologous peripheral blood for patients with systemic sclerosis: a retrospective analysis.

BACKGROUND: Autologous haemopoietic stem-cell transplantation (HSCT) benefits patients with systemic sclerosis but has been associated with significant treatment-related mortality and failure to improve diffusion capacity of carbon monoxide (DLCO). We aimed to assess efficacy of HSCT and use of rigorous cardiac screening in this group. METHODS: We assessed patients with diffuse systemic sclerosis or limited systemic sclerosis and interstitial lung disease who were treated with HSCT as part of a study or on a compassionate basis at Northwestern University (Chicago, IL, USA) or the University of São Paulo (Ribeirão Preto, Brazil). Unselected peripheral blood stem cells were harvested with cyclophosphamide (2 g/m(2)) and filgrastim. The transplant regimen was a non-myeloablative regimen of cyclophosphamide (200 mg/kg) and rabbit anti-thymocyte globulin (rATG; 4·5-6·5 mg/kg). We followed patients up to 5 years for overall survival, relapse-free survival, modified Rodnan skin score, and pulmonary function tests. FINDINGS: Five (6%) of 90 patients died from treatment-related causes. Despite standard guidelines that recommend echocardiogram for screening before transplantation, four treatment-related deaths occurred because of cardiovascular complications (one constrictive pericarditis, two right heart failures without underlying infection, and one heart failure during mobilisation), and one death was secondary to sepsis without documented underlying heart disease. Kaplan-Meier analysis showed survival was 78% at 5 years (after eight relapse-related deaths) and relapse-free survival was 70% at 5 years. Compared with baseline, we noted improvements after HSCT in modified Rodnan skin scores at 1 year (58 patients; p<0·0001), 2 years (42 patients; p<0·0001), and 3 years (27 patients; p<0·0001) and forced vital capacity at 1 year (58 patients; p=0·009), 2 years (40 patients; p=0·02), and 3 years (28 patients; p=0·004), but total lung capacity and DLCO were not improved significantly after HSCT. Overall mean DLCO was significantly improved in patients with normal baseline echocardiograms (p=0·005) or electrocardiographs (p=0·05). INTERPRETATION: Autologous HSCT with a non-myeloablative regimen of cyclophosphamide and rATG with a non-selected autograft results in sustained improvement in skin thickness and forced vital capacity. DLCO is affected by baseline cardiac function. Guidelines for cardiac screening of patients with systemic sclerosis to assess treatment-related risk from pulmonary artery hypertension, primary cardiac involvement, or pericardial disease should be reconsidered and updated. FUNDING: None.

Cyclosporine level: difference between blood samples collected through peripheral and central venous access.

AIMS AND OBJECTIVES: To identify differences in cyclosporine levels between blood samples collected from a peripheral venous access, catheter line used for drug infusion and catheter line not used for drug infusion in adult patients receiving allogeneic haematopoietic stem cell transplantation. Background. Cyclosporine is an immunosuppressant that prevents graft-versus-host disease, has a narrow therapeutic window and causes nephrotoxicity. For cyclosporine infusion, a tunnelled central venous access device is used; however, because of the lipophilic properties of the drug, it can adsorb to the catheter surface and falsely raise cyclosporine concentrations in blood specimens. DESIGN: Prospective observational study. METHODS: The study collected 135 blood samples from 16 patients. In 13 subjects, samples were obtained from the three lines at three time points (1, 7 and 14 days after the start of cyclosporine infusion), and for three subjects, samples were only obtained at 1 and 7 days after the start of infusion. The 5-ml blood discard method was used for samples collected from the catheter. Using this procedure, the catheter line was washed with saline solution, 5 ml of blood and saline solution were aspirated from the catheter line and discarded, and then sample blood used for the test was collected. The paired t-test with the Bonferroni correction was used to analyse the differences in cyclosporine serum levels. RESULTS: Significant differences were observed when the drug serum levels obtained in the line used for drug infusion were compared with the levels obtained in the line not used for infusion or the peripheral venous line. No differences in drug levels were identified in blood collected from the peripheral venous line and the line not used for drug infusion. CONCLUSION: Drug adsorption occurs in the line used for infusion. Therefore, the blood sample collected from the line not used for cyclosporine infusion can be considered reliable for drug concentration determination. RELEVANCE TO CLINICAL PRACTICE: Nurses should standardise one line of the tunnelled central venous access device for cyclosporine infusion, which avoids the need for evasive procedures and provides patients with more comfort.

Reappraisal of total body irradiation followed by bone marrow transplantation as a therapy for inflammatory bowel disease.

The main current therapies for inflammatory bowel diseases (IBD) are aimed at controlling the exacerbated inflammation in the gut. Although these therapies have been successful, they are not curative and it is not possible to predict whether a beneficial response will occur or which patients will be refractory to the treatment. Total body irradiation (TBI) associated with chemotherapy is the first choice in the treatment of some hematological disorders and is an applicable option in the preparation of patients with hematologic diseases for hematopoietic stem cell transplantation. Then, in this study we investigated the association of TBI as immunosuppressive therapy and bone marrow cell (BMC) transplantation as a strategy to induce colitis recovery and immune reconstitution in the TNBS model of intestinal inflammation. TNBS mice treated with TBI associated with BMC transplantation presented elevated gain of weight and an overall better outcome of the disease when compared to those treated only with TBI. In addition, TBI associated or not with BMC reduced the frequency of inflammatory cells in the gut and restored the goblet cell counts. These results were accompanied by a down regulation in the production of inflammatory cytokines in the colon of mice treated with TBI alone or in association with BMC transplantation. The BMC infused were able to repopulate the ablated immune system and accumulate in the site of inflammation. However, although both treatments (TBI or TBI+BMC) were able to reduce gut inflammation, TBI alone was not enough to fully restore mice weight and these animals presented an extremely reduced survival rate when their immune system was not promptly reconstituted with BMC transplantation. Finally, these evidences suggest that the BMC transplantation is an efficient strategy to reduce the harmful effects of TBI in the colitis treatment, suggesting that radiotherapy may be an important immunosuppressive therapy in patients with IBD, by modulating the local inflammatory response.

Dynamic changes of the Th17/Tc17 and regulatory T cell populations interfere in the experimental autoimmune diabetes pathogenesis.

A balance between proinflammatory (Th17 and Tc17) and anti-inflammatory (regulatory T cells) subsets of T cells is essential to maintain immunological tolerance and prevent the onset of several autoimmune diseases, including type 1 diabetes. However, the kinetics of these subsets and disease severity during the streptozotocin (STZ)-induced diabetes course has not been determined. Thus, susceptible C57BL/6 mice were administrated with multiple low doses of STZ and we evaluated the frequency/absolute number of these T cell subsets in the pancreatic lymph nodes (PLNs) and spleen and Th1, Th17, Treg cytokine production in the pancreatic tissue. At different time points of the disease progression (6, 11, 18 and 25 days after the last STZ administration), the histopathological alterations were also evaluated by H&E and immunohistochemistry staining. During the initial phase of diabetes development (day 6), we noted increased numbers of CD4(+) and CD8(+) T cells in spleen and PLNs. At the same time, the frequencies of Th17 and Tc17 cells in PLNs were also enhanced. In addition, the early augment of interferon gamma (IFN-γ), tumoral necrosis factor (TNF-α), IL-6 and IL-17 levels in pancreatic tissue correlated with pancreatic islet inflammation and mild ß-cell damage. Notably, the absolute number of Treg cells increased in PLNs during over time when compared to control group. Interestingly, increased IL-10 levels were associated with control of the inflammatory process during the late phase of the type 1 diabetes (day 25). In agreement, mice lacking the expression of IL-17 receptor (Il17r) showed impairment in STZ-induced diabetes progression, reduced peri-insulitis and beta cells preservation when compared with wild-type mice. Our findings suggest that dynamic changes of pathogenic Th17/Tc17 and regulatory T cell subsets numbers is associated with early strong inflammation in the pancreatic islets followed by late regulatory profile during the experimental STZ-induced diabetes course.

Toll-like receptor 3: implications for proinflammatory microenvironment in human breast cancer.

Under many circumstances, the host constituents that are found in the tumor microenvironment support a malignancy network and provide the cancer cells with advantages in proliferation, invasiveness and metastasis establishment at remote organs. It is known that Toll like receptors (TLRs) are expressed not only on immune cells but also on cancer cells and it has suggested a deleterious role for TLR3 in inflammatory disease. Hypothesizing that altered IFNγ signaling may be a key mechanism of immune dysfunction common to cancer as well CXCR4 is overexpressed among breast cancer patients, the mRNA expression of TLR3, CXCR4 and IFNγ in breast cancer tumor tissues was investigated. No statistically significant differences in the expression of CXCR4 mRNA, IFNγ and TLR3 between healthy and tumor tissues was observed, however, it was verified a positive correlation between mRNA relative expression of TLR3 and CXCR4 (p < 0.001), and mRNA relative expression of TLR3 was significantly increased in breast cancer tumor tissue when compared to healthy mammary gland tissue among patients expressing high IFNγ (p = 0.001). Since the tumor microenvironment plays important roles in cancer initiation, growth, progression, invasion and metastasis, it is possible to propose that an overexpression of IFNγ mRNA due to the pro-inflammatory microenvironment can lead to an up-regulation of CXCR4 mRNA and consequently to an increased TLR3 mRNA expression even among nodal negative patients. In the future, a comprehensive study of TLR3, CXCR4 and IFNγ axis in primary breast tumors and corresponding healthy tissues will be crucial to further understanding of the cancer network.

Neurovascular aspects of amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease with a complicated and poorly understood pathogenesis. Strong evidence indicates impairment of all neurovascular unit components including the blood-brain and blood-spinal cord barriers (BBB/BSCB) in both patients and animal models. The present review provides an updated analysis of the microvascular pathology and impaired BBB/BSCB in ALS. Based on experimental and clinical ALS studies, the roles of cellular components, cell interactions, tight junctions, transport systems, cytokines, matrix metalloproteinases, and free radicals in the BBB/BSCB disruption are discussed. The impact of BBB/BSCB damage in ALS pathogenesis is a novel research topic, and this review will reveal some aspects of microvascular pathology involved in the disease and hopefully engender new therapeutic approaches.

Transplantation for autoimmune diseases in north and South America: a report of the Center for International Blood and Marrow Transplant Research.

Hematopoietic cell transplantation (HCT) is an emerging therapy for patients with severe autoimmune diseases (AID). We report data on 368 patients with AID who underwent HCT in 64 North and South American transplantation centers reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2009. Most of the HCTs involved autologous grafts (n = 339); allogeneic HCT (n = 29) was done mostly in children. The most common indications for HCT were multiple sclerosis, systemic sclerosis, and systemic lupus erythematosus. The median age at transplantation was 38 years for autologous HCT and 25 years for allogeneic HCT. The corresponding times from diagnosis to HCT were 35 months and 24 months. Three-year overall survival after autologous HCT was 86% (95% confidence interval [CI], 81%-91%). Median follow-up of survivors was 31 months (range, 1-144 months). The most common causes of death were AID progression, infections, and organ failure. On multivariate analysis, the risk of death was higher in patients at centers that performed fewer than 5 autologous HCTs (relative risk, 3.5; 95% CI, 1.1-11.1; P = .03) and those that performed 5 to 15 autologous HCTs for AID during the study period (relative risk, 4.2; 95% CI, 1.5-11.7; P = .006) compared with patients at centers that performed more than 15 autologous HCTs for AID during the study period. AID is an emerging indication for HCT in the region. Collaboration of hematologists and other disease specialists with an outcomes database is important to promote optimal patient selection, analysis of the impact of prognostic variables and long-term outcomes, and development of clinical trials.

Peripheral nerve repair with cultured schwann cells: getting closer to the clinics.

Peripheral nerve injuries are a frequent and disabling condition, which affects 13 to 23 per 100.000 persons each year. Severe cases, with structural disruption of the nerve, are associated with poor functional recovery. The experimental treatment using nerve grafts to replace damaged or shortened axons is limited by technical difficulties, invasiveness, and mediocre results. Other therapeutic choices include the adjunctive application of cultured Schwann cells and nerve conduits to guide axonal growth. The bone marrow is a rich source of mesenchymal cells, which can be differentiated in vitro into Schwann cells and subsequently engrafted into the damaged nerve. Alternatively, undifferentiated bone marrow mesenchymal cells can be associated with nerve conduits and afterward transplanted. Experimental studies provide evidence of functional, histological, and electromyographical improvement following transplantation of bone-marrow-derived cells in animal models of peripheral nerve injury. This paper focuses on this new therapeutic approach highlighting its direct translational and clinical utility in promoting regeneration of not only acute but perhaps also chronic cases of peripheral nerve damage.