Transforming growth factor-beta : biology and clinical relevance

Unravelling the Impact of Cyclic Mechanical Stretch in Keratoconus-A Transcriptomic Profiling Study

Biomechanical and molecular stresses may contribute to the pathogenesis of keratoconus (KC). We aimed to profile the transcriptomic changes in healthy primary human corneal (HCF) and KC-derived cells (HKC) combined with TGFβ1 treatment and cyclic mechanical stretch (CMS), mimicking the pathophysiological condition in KC. HCFs (n = 4) and HKCs (n = 4) were cultured in flexible-bottom collagen-coated 6-well plates treated with 0, 5, and 10 ng/mL of TGFβ1 with or without 15% CMS (1 cycle/s, 24 h) using a computer-controlled Flexcell FX-6000T Tension system. We used stranded total RNA-Seq to profile expression changes in 48 HCF/HKC samples (100 bp PE, 70-90 million reads per sample), followed by bioinformatics analysis using an established pipeline with Partek Flow software. A multi-factor ANOVA model, including KC, TGFβ1 treatment, and CMS, was used to identify differentially expressed genes (DEGs, |fold change| ≥ 1.5, FDR ≤ 0.1, CPM ≥ 10 in ≥1 sample) in HKCs (n = 24) vs. HCFs (n = 24) and those responsive to TGFβ1 and/or CMS. PANTHER classification system and the DAVID bioinformatics resources were used to identify significantly enriched pathways (FDR ≤ 0.05). Using multi-factorial ANOVA analyses, 479 DEGs were identified in HKCs vs. HCFs including TGFβ1 treatment and CMS as cofactors. Among these DEGs, 199 KC-altered genes were responsive to TGFβ1, thirteen were responsive to CMS, and six were responsive to TGFβ1 and CMS. Pathway analyses using PANTHER and DAVID indicated the enrichment of genes involved in numerous KC-relevant functions, including but not limited to degradation of extracellular matrix, inflammatory response, apoptotic processes, WNT signaling, collagen fibril organization, and cytoskeletal structure organization. TGFβ1-responsive KC DEGs were also enriched in these. CMS-responsive KC-altered genes such as OBSCN, CLU, HDAC5, AK4, ITGA10, and F2RL1 were identified. Some KC-altered genes, such as CLU and F2RL1, were identified to be responsive to both TGFβ1 and CMS. For the first time, our multi-factorial RNA-Seq study has identified many KC-relevant genes and pathways in HKCs with TGFβ1 treatment under CMS, suggesting a potential role of TGFβ1 and biomechanical stretch in KC development.

Overview of First-Line and Second-Line Pharmacotherapies for Osteoarthritis with Special Focus on Intra-Articular Treatment

Osteoarthritis (OA) can be defined as the result of pathological processes of various etiologies leading to damage to the articular structures. Although the mechanism of degenerative changes has become better understood due to the plethora of biochemical and genetic studies, the drug that could stop the degenerative cascade is still unknown. All available forms of OA therapy are based on symptomatic treatment. According to actual guidelines, comprehensive treatment of OA should always include a combination of various therapeutic options aimed at common goals, which are pain relief in the first place, and then the improvement of function. Local treatment has become more common practice, which takes place between rehabilitation and pharmacological treatment in the hierarchy of procedures. Only in the case of no improvement and the presence of advanced lesions visible in imaging tests, should surgery be considered. Currently, an increasing number of studies are being published suggesting that intra-articular injections may be as effective or even more effective than non-steroidal anti-inflammatory drugs (NSAIDs) and result in fewer systemic adverse events. The most commonly used preparations are hyaluronic acid (HA), glucocorticosteroids (GS), and also platelet-rich plasma (PRP) in recent years. This review aims to present the mechanism of action and clinical effectiveness of different pharmacological options in relieving pain and improving functions in OA as well as the emerging approach in intra-articular treatment with PRP.

TGFβ-Neurotrophin Interactions in Heart, Retina, and Brain

Ischemic insults to the heart and brain, i.e., myocardial and cerebral infarction, respectively, are amongst the leading causes of death worldwide. While there are therapeutic options to allow reperfusion of ischemic myocardial and brain tissue by reopening obstructed vessels, mitigating primary tissue damage, post-infarction inflammation and tissue remodeling can lead to secondary tissue damage. Similarly, ischemia in retinal tissue is the driving force in the progression of neovascular eye diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD), which eventually lead to functional blindness, if left untreated. Intriguingly, the easily observable retinal blood vessels can be used as a window to the heart and brain to allow judgement of microvascular damages in diseases such as diabetes or hypertension. The complex neuronal and endocrine interactions between heart, retina and brain have also been appreciated in myocardial infarction, ischemic stroke, and retinal diseases. To describe the intimate relationship between the individual tissues, we use the terms heart-brain and brain-retina axis in this review and focus on the role of transforming growth factor β (TGFβ) and neurotrophins in regulation of these axes under physiologic and pathologic conditions. Moreover, we particularly discuss their roles in inflammation and repair following ischemic/neovascular insults. As there is evidence that TGFβ signaling has the potential to regulate expression of neurotrophins, it is tempting to speculate, and is discussed here, that cross-talk between TGFβ and neurotrophin signaling protects cells from harmful and/or damaging events in the heart, retina, and brain.

Targeting Immune Modulators in Glioma While Avoiding Autoimmune Conditions

Communication signals and signaling pathways are often studied in different physiological systems. However, it has become abundantly clear that the immune system is not self-regulated, but functions in close association with the nervous system. The neural-immune interface is complex; its balance determines cancer progression, as well as autoimmune disorders. Immunotherapy remains a promising approach in the context of glioblastoma multiforme (GBM). The primary obstacle to finding effective therapies is the potent immunosuppression induced by GBM. Anti-inflammatory cytokines, induction of regulatory T cells, and the expression of immune checkpoint molecules are the key mediators for immunosuppression in the tumor microenvironment. Immune checkpoint molecules are ligand-receptor pairs that exert inhibitory or stimulatory effects on immune responses. In the past decade, they have been extensively studied in preclinical and clinical trials in diseases such as cancer or autoimmune diseases in which the immune system has failed to maintain homeostasis. In this review, we will discuss promising immune-modulatory targets that are in the focus of current clinical research in glioblastoma, but are also in the precarious position of potentially becoming starting points for the development of autoimmune diseases like multiple sclerosis.

Nanocomposites drug delivery systems for the healing of bone fractures

The skeletal system is fundamental for the structure and support of the body consisting of bones, cartilage, and connective tissues. Poor fracture healing is a chief clinical problem leading to disability, extended hospital stays and huge financial liability. Even though most fractures are cured using standard clinical methods, about 10% of fractures are delayed or non-union. Despite decades of progress, the bone-targeted delivery system is still restricted due to the distinctive anatomical bone features. Recently, various novel nanocomposite systems have been designed for the cell-specific targeting of bone, enhancing drug solubility, improving drug stability and inhibiting drug degradation so that it can reach its target site without being removed in the systemic circulation. Such targeting systems could consist of biological compounds i.e. bone marrow stem cells (BMSc), growth factors, RNAi, parathyroid hormone or synthetic compounds, i.e. bisphosphonates (BPs) and calcium phosphate cement. Hydrogels and nanoparticles are also being employed for fracture healing. In this review, we discussed the normal mechanism of bone healing and all the possible drug delivery systems being employed for the healing of the bone fracture.

Knockdown of SMAD3 inhibits the growth and enhances the radiosensitivity of lung adenocarcinoma via p21 in vitro and in vivo

Radiotherapy is an effective approach for the treatment of lung adenocarcinoma. However, evidence suggests that lung adenocarcinoma can easily develop tolerance to radiotherapy. The purpose of this study was to investigate the effect and mechanism of SMAD3 on the radiosensitivity of lung adenocarcinoma in vitro and in vivo. We found that knockdown of SMAD3 using two short hairpin RNAs in lentivirus vectors significantly inhibited cell growth and increased radiosensitivity of the lung adenocarcinoma cell lines A549, H1299, and H1975. Using RNA sequencing and bioinformatics analyses, we found that the significantly differentially expressed genes in SMAD3 knockdown cells were mainly enriched in the cell cycle process. We then showed that knockdown of SMAD3 significantly reduced expression of cyclin-dependent kinase inhibitor 1 (p21) and increased the proportion of G2/M phase cells and the radiosensitivity of lung adenocarcinoma. Chromatin immunoprecipitation results in the Gene Expression Omnibus (GEO) database and our luciferase assay verified that SMAD3 directly bound the p21 promoter. A series of rescue experiments showed that overexpression of p21 partly reversed the effect of SMAD3 on proliferation and radioresistance in vitro and in vivo. Moreover, we found that the expression levels of SMAD3 and p21 were highly correlated, and both correlated with the patients' survival in online databases and clinical specimens. Expression of SMAD3 and p21 was also significantly different between radioresistant and radiosensitive patients in our hospital. Our results indicate that SMAD3 is a potential prognosis and radiosensitivity indicator as well as a target for radiotherapy and other treatments of patients with lung adenocarcinoma.

Towards the contribution of the p38MAPK pathway to the dual role of TGFβ in cancer: A boolean model approach

The transforming growth factor-beta (TGF-β) pathway is involved in the regulation of cell growth and differentiation. In normal cells or in the early stages of cancer, this pathway can control proliferation stimuli by inducing cell cycle arrest or apoptosis (through the MAP-kinase protein p38MAPK), while in late stages it seems to act as a tumor promoter. This feature is known as the TGF-β dual role in cancer and it is not completely explained. This seems to arise through the accumulation of mutations in cancer development that affect the normal function of these pathways. In this work we propose a Boolean model of the crosstalk between the TGF-β, p38 MAPK and cell cycle checkpoint pathways which qualitatively describes this dual behavior. The model shows that for the wild type case, TGF-β acts as tumor supressor by inducing cell cycle arrest or apoptosis, as expected. However, the loss of function (LoF) of its two signaling proteins: SMAD2 and SMAD3 has immortalization effects due to the activation of the PI3K/AKT pathway that contributes to inhibit apoptosis. In silico mutations of the model elements were compared with cell phenotypes in experiments presenting agreement. In addition, we performed a series of double gene perturbations (that simulate random deleterious mutations) to determine the main regulators of the network. The results suggest that SMAD2/3 and p38MAPK are key players in processing the network input. In addition, when the LoF of SMAD2/3 is combined with the LoF of p38MAPK and p53, cell cycle arrest is completely abrogated. In conclusion, the model allows to visualize, through in silico mutations, the dual role of TGF-β: for the wild-type case TGF-β is able to block proliferation, however deleterious mutations can impair cell cycle arrest promoting cellular proliferation.

miR-206/133b Cluster: A Weapon against Lung Cancer?

Lung cancer is a deadly disease that ends numerous lives around the world. MicroRNAs (miRNAs) are a group of non-coding RNAs involved in a variety of biological processes, such as cell growth, organ development, and tumorigenesis. The miR-206/133b cluster is located on the human chromosome 6p12.2, which is essential for growth and rebuilding of skeletal muscle. The miR-206/133b cluster has been verified to be dysregulated and plays a crucial role in lung cancer. miR-206 and miR-133b participate in lung tumor cell apoptosis, proliferation, migration, invasion, angiogenesis, drug resistance, and cancer treatment. The mechanisms are sophisticated, involving various target genes and molecular pathways, such as MET, EGFR, and the STAT3/HIF-1α/VEGF signal pathway. Hence, in this review, we summarize the role and potential mechanisms of the miR-206/133b cluster in lung cancer.

Smad3-related miRNAs regulated oncogenic TRIB2 promoter activity to effectively suppress lung adenocarcinoma growth

MicroRNAs (miRNAs) and Smad3, as key transcription factors in transforming growth factor-β1 (TGF-β1) signaling, help regulate various physiological and pathological processes. We investigated the roles of Smad3-regulated miRNAs with respect to lung adenocarcinoma cell apoptosis, proliferation, and metastasis. We observed that Smad3 and phospho-SMAD3 (p-Smad3) were decreased in miR-206- (or miR-140)-treated cells and there might be a feedback loop between miR-206 (or miR-140) and TGF-β1 expression. Smad3-related miRNAs affected tribbles homolog 2 (TRIB2) expression by regulating trib2 promoter activity through the CAGACA box. MiR-206 and miR-140 inhibited lung adenocarcinoma cell proliferation in vitro and in vivo by suppressing p-Smad3/Smad3 and TRIB2. Moreover, lung adenocarcinoma data supported a suppressive role for miR-206/miR-140 and an oncogenic role for TRIB2—patients with higher TRIB2 levels had poorer survival. In summary, miR-206 and miR-140, as tumor suppressors, induced lung adenocarcinoma cell death and inhibited cell proliferation by modifying oncogenic TRIB2 promoter activity through p-Smad3. MiR-206 and miR-140 also suppressed lung adenocarcinoma cell metastasis in vitro and in vivo by regulating EMT-related factors.

Mediating bone regeneration by means of drug eluting implants: From passive to smart strategies

In addition to excellent biocompatibility and mechanical performance, the new generation of bone and craniofacial implants are expected to proactively contribute to the regeneration process and dynamically interact with the host tissue. To this end, integration and sustained delivery of therapeutic agents has become a rapidly expanding area. The incorporated active molecules can offer supplementary features including promoting oteoconduction and angiogenesis, impeding bacterial infection and modulating host body reaction. Major limitations of the current practices consist of low drug stability overtime, poor control of release profile and kinetics as well as complexity of finding clinically appropriate drug dosage. In consideration of the multifaceted cascade of bone regeneration process, this research is moving towards dual/multiple drug delivery, where precise control on simultaneous or sequential delivery, considering the possible synergetic interaction of the incorporated bioactive factors is of utmost importance. Herein, recent advancements in fabrication of synthetic load bearing implants equipped with various drug delivery systems are reviewed. Smart drug delivery solutions, newly developed to provide higher tempo-spatial control on the delivery of the pharmaceutical agents for targeted and stimuli responsive delivery are highlighted. The future trend of implants with bone drug delivery mechanisms and the most common challenges hindering commercialization and the bench to bedside progress of the developed technologies are covered.

Esophageal anastomosis - how the granulation phase of wound healing improves the incidence of anastomotic leakage

A two-stage esophagectomy with an interval for reconstruction of the esophagus creates an opportunity for the esophageal stump to recover from vessel injury and allows the formation of granulation tissue rich in proangiogenic factors, including transforming growth factor β (TGF-β) and vascular endothelial growth factor A (VEGF-A), which may have an impact on anastomosis healing. The present study comprised 25 patients (27 in total, 2 succumbed to complications following surgery) who underwent two-stage esophagectomy for squamous cell carcinoma in the Department of Gastrointestinal and General Surgery, Wrocław Medical University (Wrocław, Poland) between January 2007 and December 2012. Immunohistochemical staining for VEGF-A and TGF-β was performed to evaluate esophageal wall specimens at the time of esophagostomy construction and prior to anastomosis, in which the cervical esophagus was connected with the colon or ileum. At the time of reconstructive surgery, a significant increase in microvessel density was observed in all esophageal specimens (P<0.03). Significant differences were also identified in the immunohistochemical staining intensity of TGF-β and VEGF-A in the epithelium of all esophageal specimens between biopsies obtained from normal esophageal tissues at the time of esophagectomy and during reconstructive surgery. Delayed anastomosis construction provides an advantage for the esophageal stump to accumulate proangiogenic growth factors, which overlap with the subsequent proliferative stage of the anastomosed tissue and thus supports its recovery, creating an optimal environment for the healing of any fistulas.

Association study of inflammatory genes with rheumatic heart disease in North Indian population: A multi-analytical approach

Rheumatic heart disease (RHD) is an inflammatory, autoimmune disease; occurring as a consequence of group A streptococcal infection complicated by rheumatic fever (RF). An inappropriate immune response is the central signature tune to the complex pathogenesis of RHD. However, some of those infected develop RHD, and genetic host susceptibility factors are thought to play a key role in diseasedevelopment. Therefore, the present study was designed to explore the role of genetic variants in inflammatory genes in conferring risk of RHD. The study recruited total of 700 subjects, including 400 RHD patients and 300 healthy controls. We examined the associations of 8 selected polymorphisms in seven inflammatory genes: IL-6 [rs1800795G/C], IL-10 [rs1800896G/A], TNF-A [rs1800629G/A], IL-1β [rs2853550C/T], IL-1VNTR [rs2234663], TGF-β1 [rs1800469C/T]; [rs1982073T/C], and CTLA-4 [rs5742909C/T] with RHD risk. Genotyping for all the polymorphisms was done using PCR-ARMS/PCR/RFLP methods. Multifactor dimensionality reduction and classification and regression tree approaches were combined with logistic regression to discover high-order gene-gene interactions in studiedgenes involved in RHD susceptibility.In univariate logistic regression analysis, we found significant association of variant-containing genotypes (CT&TT) of TGF-β1 869T/C [rs1982073]; [p=0.0.004 & 0.001, OR (95% CI)=1.65 (1.2-2.3) & 2.25 (1.4-3.6) respectively], variant genotype (CC) of IL-1β -511C/T [rs2853550]; [p=0.001, OR (95% CI)=2.33 (1.4-3.8)] and IL-1 VNTR [rs2234663]; [p=0.03, OR (95% CI)=5.25 (1.2-23.4)] SNPs with RHD risk. CART analysis revealed that individuals with the combined genotypes of TGF-β1T/C_ rs1982073 (CT/TT) and IL-1 β_ rs2853550 (CC) had significantly higher susceptibility for RHD [p=0.0005, OR (95% CI)=5.91 (2.9-12.5)]. In MDR analysis, TGF-β1 869T>C yielded the highest testing accuracy of 0.562. In conclusion, using multi-analytical approaches, our study revealed important role of TGF-β1 869T/C [rs1982073] in RHD susceptibility.

Co-expression of parathyroid hormone related protein and TGF-beta in breast cancer predicts poor survival outcome

Background

Better methods to predict prognosis can play a supplementary role in administering individualized treatment for breast cancer patients. Altered expressions of PTHrP and TGF-β have been observed in various types of human cancers. The objective of the current study was to evaluate the association of PTHrP and TGF-β level with the clinicopathological features of the breast cancer patients.

Methods

Immunohistochemistry was used to examine PTHrP and TGF-β protein expression in 497 cases of early breast cancer, and Kaplan-Meier method and COX’s Proportional Hazard Model were applied to the prognostic value of PTHrP and TGF-β expression.

Results

Both over-expressed TGF-β and PTHrP were correlated with the tumor in larger size, higher proportion of axillary lymph node metastasis and later clinical stage. Additionally, the tumors with a high TGF-β level developed poor differentiation, and only TGF-β expression was associated with disease-free survival (DFS) of the breast cancer patients. Followed up for a median of 48 months, it was found that only the patients with negative TGF-β expression had longer DFS (P < 0.05, log-rank test). Nevertheless, those with higher PTHrP expression tended to show a higher rate of bone metastasis (67.6 % vs. 45.8 %, P = 0.019). In ER negative subgroup, those who developed PTHrP positive expression presented poor prognosis (P < 0.05, log-rank test). The patients with both positive TGF-β and PTHrP expression were significantly associated with the high risk of metastases. As indicated by Cox’s regression analysis, TGF-β expression and the high proportion of axillary lymph node metastasis served as significant independent predictors for breast cancer recurrence.

Conclusions

TGF-β and PTHrP were confirmed to be involved in regulating the malignant progression in breast cancer, and PTHrP expression, to be associated with bone metastasis as a potential prognostic marker in ER negative breast cancer.

Direct Interaction of CD40 on Tumor Cells with CD40L on T Cells Increases the Proliferation of Tumor Cells by Enhancing TGF-β Production and Th17 Differentiation

It has recently been reported that the CD40-CD40 ligand (CD40L) interaction is important in Th17 development. In addition, transforming growth factor-beta (TGF-β) promotes tumorigenesis as an immunosuppressive cytokine and is crucial in the development of Th17 cells. This study investigated the role of CD40 in breast cancer cells and its role in immunosuppressive function and tumor progression. CD40 was highly expressed in the breast cancer cell line MDA-MB231, and its stimulation with CD40 antibodies caused the up-regulation of TGF-β. Direct CD40-CD40L interaction between MDA-MB231 cells and activated T cells also increased TGF-β production and induced the production of IL-17, which accelerated the proliferation of MDA-MB231 cells through the activation of STAT3. Taken together, the direct CD40-CD40L interaction of breast tumor cells and activated T cells increases TGF-β production and the differentiation of Th17 cells, which promotes the proliferation of breast cancer cells.

NFkappaB activation is essential for miR-21 induction by TGFβ1 in high glucose conditions

Transforming growth factor beta1 (TGFβ1) is a pleiotropic growth factor with a very broad spectrum of effects on wound healing. Chronic non-healing wounds such as diabetic foot ulcers express reduced levels of TGFβ1. On the other hand, our previous studies have shown that the microRNA miR-21 is differentially regulated in diabetic wounds and that it promotes migration of fibroblast cells. Although interplay between TGFβ1 and miR-21 are studied in relation to cancer, their interaction in the context of chronic wounds has not yet been investigated. In this study, we examined if TGFβ1 could stimulate miR-21 in fibroblasts that are subjected to high glucose environment. MiR-21 was, in fact, induced by TGFβ1 in high glucose conditions. The induction by TGFβ1 was dependent on NFκB activation and subsequent ROS generation. TGFβ1 was instrumental in degrading the NFκB inhibitor IκBα and facilitating the nuclear translocation of NFκB p65 subunit. EMSA studies showed enhanced DNA binding activity of NFκB in the presence of TGFβ1. ChIP assay revealed binding of p65 to miR-21 promoter. NFκB activation was also required for the nuclear translocation of Smad 4 protein and subsequent direct interaction of Smad proteins with primary miR-21 as revealed by RNA-IP studies. Our results show that manipulation of TGFβ1-NFκB-miR-21 pathway could serve as an innovative approach towards therapeutics to heal diabetic ulcers.

Cytokine patterns in patients with cancer: a systematic review

Active, but dysfunctional, immune responses in patients with cancer have been studied in several tumour types, but owing to the heterogeneity of cancer theories of common reaction mechanisms seem to be obsolete. In this Review of published clinical studies of patients with cancer, expression and interplay of the following cytokines are examined: interleukin 2, interleukin 6, interleukin 8, interleukin 10, interleukin 12, interleukin 18, tumour necrosis factor α (TNFα), transforming growth factor β (TGFβ), interferon-γ, HLA-DR, macrophage migration inhibitory factor (MIF), and C-X-C motif chemokine receptor 4 (CXCR4). Clinical data were analysed in a non-quantitative descriptive manner and interpreted with regard to experimentally established physiological cytokine interactions. The clinical cytokine pattern that emerged suggests that simultaneous immunostimulation and immunosuppression occur in patients with cancer, with increased concentrations of the cytokines MIF, TNFα, interleukin 6, interleukin 8, interleukin 10, interleukin 18, and TGFβ. This specific cytokine pattern seems to have a prognostic effect, since high interleukin 6 or interleukin 10 serum concentrations are associated with negative prognoses in independent cancer types. Although immunostimulatory cytokines are involved in local cancer-associated inflammation, cancer cells seem to be protected from immunological eradication by cytokine-mediated local immunosuppression and a resulting defect of the interleukin 12-interferon-γ-HLA-DR axis. Cytokines produced by tumours might have a pivotal role in this defect. A working hypothesis is that the cancer-specific and histology-independent uniform cytokine cascade is one of the manifestations of the underlying paraneoplastic systemic disease, and this hypothesis links the stage of cancer with both the functional status of the immune system and the patient's prognosis. Neutralisation of this cytokine pattern could offer novel and so far unexploited treatment approaches for cancer.

Critical Role of Transforming Growth Factor Beta in Different Phases of Wound Healing

SIGNIFICANCE

This review highlights the critical role of transforming growth factor beta (TGF-β)1-3 within different phases of wound healing, in particular, late-stage wound healing. It is also very important to identify the TGF-β1-controlling factors involved in slowing down the healing process upon wound epithelialization.

RECENT ADVANCES

TGF-β1, as a growth factor, is a known proponent of dermal fibrosis. Several strategies to modulate or regulate TGF's actions have been thoroughly investigated in an effort to create successful therapies. This study reviews current discourse regarding the many roles of TGF-β1 in wound healing by modulating infiltrated immune cells and the extracellular matrix.

CRITICAL ISSUES

It is well established that TGF-β1 functions as a wound-healing promoting factor, and thereby if in excess it may lead to overhealing outcomes, such as hypertrophic scarring and keloid. Thus, the regulation of TGF-β1 in the later stages of the healing process remains as critical issue of which to better understand.

FUTURE DIRECTIONS

One hypothesis is that cell communication is the key to regulate later stages of wound healing. To elucidate the role of keratinocyte/fibroblast cross talk in controlling the later stages of wound healing we need to: (1) identify those keratinocyte-released factors which would function as wound-healing stop signals, (2) evaluate the functionality of these factors in controlling the outcome of the healing process, and (3) formulate topical vehicles for these antifibrogenic factors to improve or even prevent the development of hypertrophic scarring and keloids as a result of deep trauma, burn injuries, and any type of surgical incision.

Tgf-β1 inhibits Cftr biogenesis and prevents functional rescue of ΔF508-Cftr in primary differentiated human bronchial epithelial cells

CFTR is an integral transmembrane glycoprotein and a cAMP-activated Cl(-) channel. Mutations in the CFTR gene lead to Cystic Fibrosis (CF)-an autosomal recessive disease with majority of the morbidity and mortality resulting from airway infection, inflammation, and fibrosis. The most common disease-associated mutation in the CFTR gene-deletion of Phe508 (ΔF508) leads to a biosynthetic processing defect of CFTR. Correction of the defect and delivery of ΔF508-CFTR to the cell surface has been highly anticipated as a disease modifying therapy. Compared to promising results in cultured cell this approach was much less effective in CF patients in an early clinical trial. Although the cause of failure to rescue ΔF508-CFTR in the clinical trial has not been determined, presence of factor(s) that interfere with the rescue in vivo could be considered. The cytokine TGF-β1 is frequently elevated in CF patients. TGF-β1 has pleiotropic effects in different disease models and genetic backgrounds and little is known about TGF-β1 effects on CFTR in human airway epithelial cells. Moreover, there are no published studies examining TGF-β1 effects on the functional rescue of ΔF508-CFTR. Here we found that TGF-β1 inhibits CFTR biogenesis by reducing mRNA levels and protein abundance in primary differentiated human bronchial epithelial (HBE) cells from non-CF individuals. TGF-β1 inhibits CFTR biogenesis without compromising the epithelial phenotype or integrity of HBE cells. TGF-β1 also inhibits biogenesis and impairs the functional rescue of ΔF508-CFTR in HBE cells from patients homozygous for the ΔF508 mutation. Our data indicate that activation of TGF-β1 signaling may inhibit CFTR function in non-CF individuals and may interfere with therapies directed at correcting the processing defect of ΔF508-CFTR in CF patients.

Mesenchymal stromal cells and regulatory T cells: the Yin and Yang of peripheral tolerance?

In recent years, mesenchymal stromal cells (MSCs) and regulatory T cells (Tregs) have both garnered significant interest from immunologists worldwide, not least because of the potential application of both cell types in the treatment of many chronic inflammatory and autoimmune diseases. Although both MSCs and Tregs can be considered immunosuppressive in their own right, the induction of Tregs by activated MSCs is now a well-publicised phenomenon; however, only recently have the mechanisms involved in this induction started to become clear. Indeed, it is becoming increasingly apparent that there exists a complex interplay between the two lineages leading to this potent inhibition of the host immune response. Cell contact, soluble mediators-including prostaglandin E(2) and transforming growth factor β-and indirect induction via manipulation of other antigen-presenting cells all appear to have vital roles in the interactions between MSCs and Tregs. Much still remains to be discovered before we have a full understanding of this important aspect of the immune response, but there have already been a multitude of clinical trials suggesting that MSC/Treg therapies could offer significant benefits in the treatment of both autoimmune disease and graft versus host disease. Although these therapies are still in their infancy, the synergy between MSCs and Tregs will undoubtedly yield future breakthroughs in the treatment of many debilitating conditions and usher in a new wave of targeted, cell-based therapeutics.

Stage-dependent association of BDNF and TGF-β1 with lung function in stable COPD

Background

Chronic Obstructive Pulmonary Disease (COPD) is characterised by complex inflammatory, neuronal and fibrotic changes. Brain-derived Neurotrophic Factor (BDNF) is a key regulator of neuronal plasticity, whereas Transforming Growth Factor-β₁ (TGF-β₁) plays a crucial role in tissue repair and emphysema pathogenesis. Both mediators are stored in platelets and released from platelets in inflammatory conditions and during serum preparation. In patients with asthma, it was previously shown that elevated serum BDNF concentrations correlate with disease severity, whereas TGF-β₁ concentrations were normal.

Methods

In the present study, 63 patients with stable COPD (spirometric GOLD stages 2–4) and 17 age- and comorbidity-matched controls were studied. Lung function, smoking history, medication, platelet concentrations in peripheral blood and serum concentrations of BDNF, TGF-β₁ and Serotonin (5-HT) were assessed in all participants.

Results

Serum levels of both BDNF and TGF-β₁ (but not concentrations of platelets in peripheral blood) were significantly elevated in all stages of COPD as compared to controls. Highest BDNF concentrations were found in spirometric GOLD stage 3, whereas highest TGF-β₁ serum levels were found in spirometric GOLD stage 4. There were specific, stage-dependent correlations of these mediators with lung function parameters of the patients.

Conclusions

Taken together, we show that, in contrast to asthma, COPD is characterised by elevated concentrations of both BDNF and TGF-β₁ in serum. The stage-dependent association with lung function supports the hypothesis that these platelet mediators may play a role in the pathogenesis of COPD.

Pathway-based evaluation in early onset colorectal cancer suggests focal adhesion and immunosuppression along with epithelial-mesenchymal transition

Colorectal cancer (CRC) has one of the highest incidences among all cancers. The majority of CRCs are sporadic cancers that occur in individuals without family histories of CRC or inherited mutations. Unfortunately, whole-genome expression studies of sporadic CRCs are limited. A recent study used microarray techniques to identify a predictor gene set indicative of susceptibility to early-onset CRC. However, the molecular mechanisms of the predictor gene set were not fully investigated in the previous study. To understand the functional roles of the predictor gene set, in the present study we applied a subpathway-based statistical model to the microarray data from the previous study and identified mechanisms that are reasonably associated with the predictor gene set. Interestingly, significant subpathways belonging to 2 KEGG pathways (focal adhesion; natural killer cell-mediated cytotoxicity) were found to be involved in the early-onset CRC patients. We also showed that the 2 pathways were functionally involved in the predictor gene set using a text-mining technique. Entry of a single member of the predictor gene set triggered a focal adhesion pathway, which confers anti-apoptosis in the early-onset CRC patients. Furthermore, intensive inspection of the predictor gene set in terms of the 2 pathways suggested that some entries of the predictor gene set were implicated in immunosuppression along with epithelial-mesenchymal transition (EMT) in the early-onset CRC patients. In addition, we compared our subpathway-based statistical model with a gene set-based statistical model, MIT Gene Set Enrichment Analysis (GSEA). Our method showed better performance than GSEA in the sense that our method was more consistent with a well-known cancer-related pathway set. Thus, the biological suggestion generated by our subpathway-based approach seems quite reasonable and warrants a further experimental study on early-onset CRC in terms of dedifferentiation or differentiation, which is underscored in EMT and immunosuppression.

Transforming growth factor-β protein inversely regulates in vivo differentiation of interleukin-17 (IL-17)-producing CD4+ and CD8+ T cells

TGF-β is a pleiotropic cytokine that predominantly exerts inhibitory functions in the immune system. Unexpectedly, the in vitro differentiation of both Th17 and Tc17 cells requires TGF-β. However, animals that are impaired in TGF-β signaling (TGF-βRIIDN mice) display multiorgan autoimmune disorders. Here we show that CD4⁺ T cells from TGF-βRIIDN mice are resistant to Th17 cell differentiation and, paradoxically, that CD8⁺ T cells from these animals spontaneously acquire an IL-17-producing phenotype. Neutralization of IL-17 or depletion of CD8⁺ T cells dramatically inhibited inflammation in TGF-βRIIDN mice. Therefore, the absence of TGF-β triggers spontaneous differentiation of IL-17-producing CD8⁺ T cells, suggesting that the in vivo and in vitro conditions that promote the differentiation of IL-17-producing CD8⁺ T cells are distinct.

Anti-carcinogenic action of ellagic acid mediated via modulation of oxidative stress regulated genes in Dalton lymphoma bearing mice

An elevated level of reactive oxygen species (ROS) in a cancerous condition causes oxidative stress which in turn activates a number of genes, and therefore an interruption in the oxidative microenvironment should be able to inactivate these genes, contributing to cancer prevention. The present work was designed to evaluate the role of ellagic acid in the modulation of protein kinase Cα (PKCα) activity and expression and its correlation with the oncogene, c-Myc, and tumor suppressor gene, transforming growth factor-β (TGF-β1), in lymphoma bearing mice. We also evaluated its implication for cell viability. Our results show that ellagic acid leads to down-regulation of the expression and activity of PKCα via decreasing the oxidative stress, measured in terms of lipid peroxidation and protein carbonylation. It also reduces c-Myc expression and improves TGF-β1 expression besides decreasing cell viability in Dalton lymphoma bearing mice, which supports its anti-carcinogenic action.

Association of transforming growth factor-β1 gene C-509T and T869C polymorphisms with atherosclerotic cerebral infarction in the Chinese: a case-control study

Background

Transforming growth factor-β1 (TGF-β1) is a multifunctional cytokine involved in inflammation and pathogenesis of atherosclerosis. There is scant information on the relation between variations within the TGF-β1 gene polymorphisms and risks of ischemic cerebrovascular diseases. Therefore, this case-controlled study was carried out to investigate the possible association of the TGF-β1 gene C-509T and T869C polymorphisms, and their combined genotypes with the risk of atherosclerotic cerebral infarction (CI) in the Chinese population.

Results

We recruited 164 CI patients and 167 healthy control subjects who were frequency-matched for age and gender. The frequencies of the -509TT genotype and T allele gene were significantly higher in the CI group (P = 0.007, P = 0.006). The frequencies of +869CC genotype and C allele were higher in the CI group (P = 0.002, P = 0.004). In the CI group, the individuals with -509TT genotype had a significantly higher level of plasma triglyceride (TG) (P = 0.017). +869CC genotype correlated significantly with higher level of plasma low density lipoprotein cholesterol (LDL-c) in the CI group (P = 0.015). With haplotype analysis, the frequency of the -509T/+869C combined genotype was significantly higher in the CI group than in controls (P < 0.001).

Conclusions

Our study suggests that C-509T and T869C gene polymorphisms in TGF-β1 may be a critical risk factor of genetic susceptibility to CI in the Chinese population.

Transforming growth factor-β signaling pathway activation in Keratoconus

PURPOSE

To assess the presence of transforming growth factor-β (TGFβ) pathway markers in the epithelium of keratoconus patient corneas.

DESIGN

Retrospective, comparative case series of laboratory specimens.

METHODS

Immunohistochemistry results for TGFβ2, total TGFβ, mothers against decacentaplegic homolog (Smad) 2, and phosphorylated Smad2 was performed on formalin-fixed, paraffin-embedded sections of keratoconus patient corneas and normal corneas from human autopsy eyes. Keratoconus patient corneas were divided in two groups, depending on their severity based on keratometer readings and pachymetry. Autopsy controls were age-matched with the keratoconus cases. Immunohistochemistry signal quantification was performed using automated software. Real-time reverse-transcriptase polymerase chain reaction was performed on total ribonucleic acid of epithelium of keratoconus patient corneas and autopsy control corneas.

RESULTS

Immunohistochemistry quantification showed a significant increase in mean signal in the group of severe keratoconus cases compared with normal corneas for TGFβ2 and phosphorylated Smad2 (P < .05). Immunohistochemistry analysis using antibodies against total TGFβ and Smad2 did not show any significant increase in the keratoconus cases versus the autopsy controls. Reverse-transcriptase polymerase chain reaction exhibited elevated messenger ribonucleic acid levels of Smad2 and TGFβ2 in severe keratoconus corneal epithelium.

CONCLUSIONS

This work shows increased TGFβ pathway markers in severe keratoconus cases and provides the rationale for investigating TGFβ signaling further in the pathophysiology of keratoconus.

The functional class evaluated in rheumatoid arthritis is associated with soluble TGF-β1 serum levels but not with G915C (Arg25Pro) TGF-β1 polymorphism

The influence of genetic factors in rheumatoid arthritis (RA) has been described, including several cytokine genes such as transforming growth factor β (TGF-β) with regulatory effects on lymphocytes, dendritic cells, macrophages, chondrocytes, and osteoblasts, which are important in the RA pathogenesis. The G915C TGF-β1 polymorphism has been associated with soluble TGF-β1 (sTGF-β) serum levels. Thus, we studied the association of G915C (Arg25Pro) TGF-β1 polymorphism with sTGF-β1 serum levels in RA. We enrolled 120 RA patients and 120 control subjects (CS). The G915C TGF-β1 polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, and sTGF-β1 serum levels were quantified using an ELISA kit. The genotype frequency of G915C TGF-β1 polymorphism in RA and CS was G/G (91.7%), G/C (8.3%), C/C (0%) and G/G (85.8%), G/C (14.2%), C/C (0%), respectively, without significant differences. Moreover, the G/G TGF-β1 genotype carriers presented the highest disability index evaluated for the Spanish HAQ-DI score (P < 0.001). In addition, the sTGF-β1 serum levels were higher in RA (182.2 ng/mL) than CS (160.2 ng/mL), there was not significant difference. However, we found a positive correlation between the sTGF-β1 serum levels and the functional class (r = 0.472, P = 0.023). In conclusion, the G915C (Arg25Pro) TGF-β1 polymorphism is not associated with RA, but the sTGF-β1 serum levels are related with the functional class in RA.

Transforming growth factor beta and soluble endoglin in the healthy senior and in Alzheimer's disease patients

OBJECTIVES

Senescence of the immune system and of endothelial cells can contribute to age-dependent vascular and neurodegenerative disorders including Alzheimer's disease. The aim of this study is an assessment of putative relationships of serum levels of transforming growth factor beta (TGFβ) and soluble endoglin (sCD105) and neurodegeneration, and of changes of these molecules in the course of ageing.

DESIGN

The subjects of the study consisted of three groups, the first one was 63 otherwise healthy middle - aged participants, 31 females, 32 males, of average age 35 years. The second group was formed by 58 healthy, self-dependent inhabitants of nursing homes, 44 females and 14 males, average age 83.5 years. The third group comprised of 129 Alzheimer's disease patients, 86 females, 43 males, of average age 80 years, with MMSE score that ranged from 16 to 20.

MEASUREMENT

Serum levels of TGF beta and soluble endoglin were measured by the ELISA method in samples of peripheral blood using commercial kits.

RESULTS

The serum level of TGFβ was 34,339 ± 6,420 pg/ml in the healthy younger group, 37,555 ± 11,944 pg/ml in the healthy seniors, and 29,057 ± 11,455 pg/ml in Alzheimer's disease patients. Compared to healthy seniors, the serum level of TGFβ was significantly decreased in Alzheimer's disease patients (p < 0.01). The serum level of endoglin were 4.88 ± 0.95 μg/ml in the healthy younger group; 6.11 ± 1.38 μg/ml in healthy seniors, and 7.20 ± 1.72 μg/ml in patients with Alzheimer's disease, respectively. The serum level of endoglin was significantly higher (p < 0.001) in senescent healthy persons compared to the younger control group. When compared with healthy seniors, patients with Alzheimer's disease had significantly elevated (p < 0.001) serum level of endoglin.

CONCLUSIONS

Decreased levels of TGF β in Alzheimer's disease may result in impairment of cerebral circulation reflected in the increased endoglin levels. These findings may indicate involvement of the immune system in Alzheimer's disease pathogenesis.

Serum and tissue transforming [corrected] growth factor β1 in children with biliary atresia

BACKGROUND

Biliary atresia (BA) is an infantile disorder characterized by the obstruction of a portion or the entirety of the extrahepatic bile ducts, leading to hepatic fibrosis and loss of liver function. The gold standard for diagnosing and grading fibrosis is liver biopsy, but there are many groups searching for noninvasive biomarkers that could replace and/or complement this procedure.

METHODS AND MATERIALS

In this study, we evaluated serum and tissue transforming growth factor β1 (TGFβ1) and aspartate aminotransferase [AST]-to-platelet ratio index (APRI) in patients with BA at the time of diagnosis and at liver transplantation and correlated these data with tissue collagen density, to verify if they could act as biomarkers for BA.

RESULTS

At the time of diagnosis, TGFβ1 levels were highly variable in BA patients. However, serum values at transplantation were significantly decreased (13.75 ± 3.68 ng/mL) as compared to controls (34.36 ± 9.35 ng/mL) (P = .01). No correlation was found between serum TGF1β1 and collagen density in both groups analyzed. Serum TGFβ1 showed no correlation with APRI at diagnosis. At the time of liver transplantation, all patients had low serum TGFβ1 and variable APRI, although all higher than 2.0. However, when platelet count was used, an inverse correlation with serum TGFβ1 was observed at the time of diagnostics (r(2) = 0.749; P = .03).

CONCLUSIONS

Our findings suggest that at the time of diagnosis the fibrogenic process is active, with higher levels of TGFβ1, whereas later on, there is scar tissue, with reduced TGFβ1 expression. Although our results should be confirmed in larger sets of patients with BA, the lack of TGFβ1 at the time of liver transplantation may have important consequences for the patient because it is a pleiotropic molecule, responsible for many functions in the body, mainly those related to immune response and cell growth.

Radiotherapy suppresses angiogenesis in mice through TGF-betaRI/ALK5-dependent inhibition of endothelial cell sprouting

Background

Radiotherapy is widely used to treat cancer. While rapidly dividing cancer cells are naturally considered the main target of radiotherapy, emerging evidence indicates that radiotherapy also affects endothelial cell functions, and possibly also their angiogenic capacity. In spite of its clinical relevance, such putative anti-angiogenic effect of radiotherapy has not been thoroughly characterized. We have investigated the effect of ionizing radiation on angiogenesis using in vivo, ex vivo and in vitro experimental models in combination with genetic and pharmacological interventions.

Principal Findings

Here we show that high doses ionizing radiation locally suppressed VEGF- and FGF-2-induced Matrigel plug angiogenesis in mice in vivo and prevented endothelial cell sprouting from mouse aortic rings following in vivo or ex vivo irradiation. Quiescent human endothelial cells exposed to ionizing radiation in vitro resisted apoptosis, demonstrated reduced sprouting, migration and proliferation capacities, showed enhanced adhesion to matrix proteins, and underwent premature senescence. Irradiation induced the expression of P53 and P21 proteins in endothelial cells, but p53 or p21 deficiency and P21 silencing did not prevent radiation-induced inhibition of sprouting or proliferation. Radiation induced Smad-2 phosphorylation in skin in vivo and in endothelial cells in vitro. Inhibition of the TGF-β type I receptor ALK5 rescued deficient endothelial cell sprouting and migration but not proliferation in vitro and restored defective Matrigel plug angiogenesis in irradiated mice in vivo. ALK5 inhibition, however, did not rescue deficient proliferation. Notch signaling, known to hinder angiogenesis, was activated by radiation but its inhibition, alone or in combination with ALK5 inhibition, did not rescue suppressed proliferation.

Conclusions

These results demonstrate that irradiation of quiescent endothelial cells suppresses subsequent angiogenesis and that ALK5 is a critical mediator of this suppression. These results extend our understanding of radiotherapy-induced endothelial dysfunctions, relevant to both therapeutic and unwanted effects of radiotherapy.

Peptide inhibitors of transforming growth factor-beta enhance the efficacy of antitumor immunotherapy

Transforming growth factor-beta (TGF-beta) is a cytokine with potent immunosuppressive effects and is overexpressed in many tumors. Therefore, development of molecules able to inhibit TGF-beta is of paramount importance to improve the efficacy of antitumor immunotherapy. TGF-beta inhibitor peptides P144 and P17 were combined with the administration of adjuvant molecules poly(I:C) and agonistic anti-CD40 antibodies, and their effect on the growth of E.G7-OVA established tumors and on antitumor immune response was evaluated. Tumor rejection efficacy of a single administration of adjuvants was enhanced from 15 to 70 % when combined with repeated injections of TGF-beta inhibitor peptides. Simultaneous administration of adjuvants and TGF-beta inhibitor peptides was required for maximal therapeutic efficacy. Although tumor cells produced TGF-beta, it was found that the beneficial effect of peptide administration was mainly due to the inhibition of TGF-beta produced by regulatory CD4(+)CD25(+) T cells rather than by tumor cells. The enhanced antitumor effect was accompanied by a higher activity of dendritic cells, natural killer cells and tumor antigen-specific T cells, as well as by a decrease in the number of myeloid-derived suppressor cells. In conclusion, administration of peptide inhibitors of TGF-beta in therapeutic vaccination enhances the efficacy of immunotherapy by increasing antitumor immune responses. These peptide inhibitors may have important applications for current immunotherapeutic strategies.

MMPs, TIMP-2, and TGF-beta1 in the cancerization of oral lichen planus

BACKGROUND

Matrix metalloproteinases (MMPs) and transforming growth factor-beta1 (TGF-beta1) are important in many physiological and pathological processes.

METHODS

Immunohistochemistry for MMP-2, MMP-9, membrane-type 1 MMP (MT1-MMP, MMP-14), tissue inhibitor of matrix metalloproteinase (TIMP)-2, and TGF-beta were performed on normal mucosa, nonatrophic oral lichen planus, atrophic oral lichen planus, and oral squamous cell carcinomas (OSCC) resulting from lichen planus.

RESULTS

Expression of MMPs progressively increased from normal mucosa to nonatrophic oral lichen planus, atrophic oral lichen planus, and OSCCs. Immunoscores of MMPs in atrophic oral lichen planus was significantly greater than nonatrophic oral lichen planus. Moreover, immunoscore of MMP-9 of OSCCs was significantly greater than both atrophic and nonatrophic lichen planus. Furthermore, expression of TIMP-2 and TGF-beta1 paralleled increases seen with MMPs.

CONCLUSIONS

Imbalance between MMPs and TIMPs may be involved in cancerization of oral lichen planus. MMP-2, MT1-MMP, and especially MMP-9 may be useful markers for judging potency of malignant transformation from oral lichen planus.

Expression, purification and characterization of BG(E)RII: a novel pan-TGFbeta inhibitor

Transforming growth factor beta (TGFbeta) isoforms are known to be upregulated during the progression of some diseases. They have been shown to stimulate invasion and metastasis during carcinogenesis and promote many pathological fibrotic diseases when overstimulated. This involvement in late-stage carcinoma and pathological fibrosis makes TGFbeta isoforms prime targets for therapeutic intervention. Although soluble ectodomains of TGFbeta type II (RII) and betaglycan (BG) have been utilized as TGFbeta inhibitors, their antagonistic potency against different TGFbeta isoforms varies considerably because RII does not appreciably bind to TGFbeta2 whereas BG binds weakly to TGFbeta1 and TGFbeta3. In this study, we have successfully constructed and expressed a recombinant fusion protein containing the endoglin domain of BG (BG(E)) and the extracellular domain of RII. The fusion protein (named BG(E)RII) was purified from bacterial inclusion bodies by immobilized metal ion chromatography, refolded and characterized. It bound with higher affinity to TGFbeta1 and TGFbeta3 than a commercially available soluble RII and to TGFbeta2 than a commercially available soluble BG. More significantly, whereas BG(E) or RII alone showed no antagonistic activity towards TGFbeta2, BG(E)RII inhibited the signaling of both TGFbeta1 and TGFbeta2 in cell-based assays including TGFbeta-induced phosphorylation of Smad2 and Smad3, and transcription from a TGFbeta-responsive promoter more effectively than equimolar concentrations of either RII or BG. After further purification by gel filtration chromatography, BG(E)RII was found to have greater activity than other potent TGFbeta inhibitors in blocking the signaling of TGFbeta1 and TGFbeta3. Thus, BG(E)RII is a potent pan-TGFbeta inhibitor in vitro and has potential for blocking TGFbeta-induced pathogenesis in vivo.

Transgelin is a direct target of TGF-beta/Smad3-dependent epithelial cell migration in lung fibrosis

Enhanced transforming growth factor (TGF) -beta signaling contributes to idiopathic pulmonary fibrosis (IPF), a progressive and fatal disease characterized by alveolar epithelial type II (ATII) cell hyperplasia, (myo)fibroblast accumulation, and excessive extracellular matrix deposition. TGF-beta is a potent inducer of lung fibrosis, and it regulates the ATII cell phenotype; however, direct TGF-beta target genes controlling the ATII cell phenotype remain elusive. Here, we identified the transgelin (tagln) gene as a novel immediate target of TGF-beta/Smad3-dependent gene expression in ATII cells using a Smad3 chromatin immunoprecipitation (ChIP) screen. Direct ChIP confirmed the rapid and specific binding of Smad3 to the tagln promoter. Luciferase assays demonstrated transactivation of the tagln promoter by activin-like kinase (Alk) 5-mediated TGF-beta signaling. TGF-beta treatment resulted in rapid up-regulation of tagln, but not tagln2, mRNA and protein expression, assessed by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. In vivo, tagln expression was significantly increased in ATII cells of mice during bleomycin-induced lung fibrosis, as well as in lung specimen obtained from IPF patients, as assessed by RT-PCR and immunohistochemistry. Knockdown of tagln using siRNA inhibited TGF-beta-induced migration of lung epithelial A549 cells, as well as primary ATII cells. We thus identified tagln as a novel target of TGF-beta/Smad3-dependent gene expression in ATII cells. Increased ATII cell expression of tagln in experimental and idiopathic pulmonary fibrosis may contribute to TGF-beta-dependent ATII cell injury, repair, and migration in lung fibrosis.

Cytokine gene polymorphisms in Colombian patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) patients exhibit alterations in cytokine production that may be relevant to SLE pathogenesis. There is evidence that cytokine gene polymorphisms control cytokine production; thus, these polymorphisms may be associated with SLE or its clinical manifestations. To establish the association of tumor necrosis factor alpha (TNF-alpha), transforming growth factor (TGF) beta1, interleukin (IL)-10, and IL-6 gene polymorphisms in Colombian SLE patients and their clinical manifestations, 120 SLE patients and 102 healthy controls were studied. Single nucleotide polymorphisms were studied by sequence-specific primers polymerase chain reaction (SSP-PCR) at: TNFalpha-308 (G/A), TGFbeta1 codon 10 (C/T) and codon 25 (G/C), IL-10 -1082 (G/A), -819 (C/T) and -592 (C/A), and IL-6 + 174 (G/C). Human leukocyte antigen (HLA)-DRbeta1 was typed by SSP-PCR. SLE patients had increased frequency of allele C at TGFbeta1 codon 25 (P = 0.0001, odds ratio (OR): 4.25, 95% confidence interval (CI): 2.17-8.35) and allele A at TNFalpha-308 (P = 0.0004 OR: 3.9, 95% CI: 1.65-5.80) compared with healthy controls. There was higher frequency of GC genotype at TGFbeta1 codon 25 in SLE patients (P < 0.0001). Extended genotypic analysis showed that SLE patients have decreased frequency of TNFalphaLow/TGFbeta1High (0.50) compared with healthy controls (0.80) (P < 0.0001). No association was found between these polymorphisms and SLE clinical manifestations except for Sm and Ro autoantibodies that were associated with TNFalpha allele A. There is an association between TNFalpha-308A/TGFbeta1 codon 25C with SLE susceptibility in Colombian population. This association may result in a highly inflammatory response with a decrease regulatory function mediated by TNFalpha and TGFbeta1, respectively. The TNFalpha-308A/TGFbeta1 25C genotype may be one component of genetic susceptibility to SLE in Colombian population.

Investigation of TGFB2 as a candidate gene in multiple sclerosis and Parkinson’s disease

Given the known roles of TGFbeta2 in both regulating the immune system and promoting the survival of dopaminergic neurons, it is feasible that genetic variations in TGFB2 might play an aetiological role in neurological diseases such as Multiple Sclerosis (MS) and Parkinson's disease (PD). Hence we performed an indirect association analysis of TGFB2 using 8 haplotype-tagging SNPs in a population of 937 MS patients, 538 PD cases and 2022 controls. We found no evidence for association with susceptibility or progression of MS, but have demonstrated a trend towards association of the 5' region of the gene with susceptibility to PD. Further analysis of TGFB2 is warranted in other PD cohorts.

Transcriptome analysis of the salivary glands of Dermacentor andersoni Stiles (Acari: Ixodidae)

Amongst blood-feeding arthropods, ticks of the family Ixodidae (hard ticks) are vectors and reservoirs of a greater variety of infectious agents than any other ectoparasite. Salivary glands of ixodid ticks secrete a large number of pharmacologically active molecules that not only facilitate feeding but also promote establishment of infectious agents. Genomic, proteomic and immunologic characterization of bioactive salivary gland molecules are, therefore, important as they offer new insights into molecular events occurring at the tick-host interface and they have implications for development of novel control strategies. The present work uses complementary DNA (cDNA) sequence analysis to identify salivary gland transcripts expressed by the Rocky Mountain wood tick, Dermacentor andersoni, a vector of the human pathogens causing Rocky Mountain spotted fever, Colorado tick fever, tularemia, and Powassan encephalitis as well as the veterinary pathogen Anaplasma marginale. Dermacentor andersoni is also capable of inducing tick paralysis. Automated single-pass DNA sequencing was conducted on 1440 randomly selected cDNA clones from the salivary glands of adult female D. andersoni collected during the early stages of feeding (18-24h). Analysis of the expressed sequence tags (ESTs) resulted in 544 singletons and 218 clusters with more than one quality read and attempts were made to assign putative functions to tick genes based on amino acid identity to published protein databases. Approximately 25.6% (195) of the sequences showed limited or no homology to previously identified gene products. A number of novel sequences were identified which presented significant sequence similarity to mammalian genes normally associated with extracellular matrix (ECM), regulation of immune responses, tumor suppression, and wound healing. Several coding sequences possessed various degrees of homology to previously described proteins from other tick species. Preliminary nucleotide variation analysis of these and other tick sequences suggests extensive nucleotide diversity, which has implications for evolution of tick feeding. Intra-species diversity studies can be a promising tool for identifying sequence variations potentially associated with phenotypic traits affecting vector-host-pathogen interactions.