Immunization with Bivalent Flagellin Protects Mice against Fatal Pseudomonas aeruginosa Pneumonia

Pseudomonas aeruginosa lung infections present a major challenge to healthcare systems worldwide because they are commonly associated with high morbidity and mortality. Here, we demonstrate the protective efficacy of type a and b flagellins (bivalent flagellin) against acute fatal pneumonia in mice. Mice immunized intranasally with a bivalent flagellin vaccine were challenged by different flagellated strains of P. aeruginosa in an acute pneumonia model. Besides the protective effect of the vaccine, we further measured the host innate and cellular immunity responses. The immunized mice in our study were protected against both strains. Remarkably, active immunization with type a or b flagellin significantly improved survival of mice against heterologous strain compared to flagellin a or b antisera. We also showed that after an intranasal challenge by P. aeruginosa strain, neutrophils are recruited to the airways of vaccinated mice, and that the bivalent flagellin vaccine was proved to be protective by the generated CD4+IL-17+ Th17 cells. In conclusion, bivalent flagellin vaccine can confer protection against different strains of P. aeruginosa in an acute pneumonia mouse model by eliciting effective cellular and humoral immune responses, including increased IL-17 production and improved opsonophagocytic killing

High-levelexpression of functional recombinant human coagulation factor VII in insect cells

Abstract: Recombinant coagulation factor VII (FVII) is used as a potential therapeutic intervention in hemophilia patients who produce antibodies against the coagulation factors. Mammalian cell lines provide low levels of expression, however, the Spodoptera frugiperda Sf9 cell line and baculovirus expression system are powerful systems for high-level expression of recombinant proteins, but due to the lack of endogenous vitamin K-dependent carboxylase, expression of functional FVII using this system is impossible. In the present study, we report a simple but versatile method to overcome the defect for high-level expression of the functional recombinant coagulation FVII in Sf9 cells. This method involves simultaneous expression of both human γ-carboxylase (hGC) and human FVII genes in the host. It may be possible to express other vitamin K-dependent coagulation factors using this method in the future. Keywords: Baculovirus; γ-carboxylase; Coagulation FVII; Factor VII; Insect cel

Neutrophil Gelatinase-Associated Lipocalin induces the expression of heme oxygenase-1 and superoxide dismutase 1, 2

Lipocalin-2 (Lcn2, NGAL) is a member of the lipocalin super family with diverse function such as the induction of apoptosis, the suppression of bacterial growth, and modulation of inflammatory response. Much interest has recently been focused on the physiological/pathological role of the lipocalin-2 that is considered to be a novel protective factor against oxidative stress. However, its precise biological roles in this protection are not fully understood. In this report we intended to test the effect of lipocalin-2 on the expression of heme oxygenase (1, 2) and superoxide dismutase (1, 2) which are two strong antioxidants. NGAL was cloned to pcDNA3.1 plasmid by using genetic engineering method. The recombinant vector was transfected to CHO and HEK293T to establish stable cell expressing NGAL and the expression of HO-1, 2 and SOD1, 2 were compared with appropriate controls byRT-PCR and western blot. On the other hand, expression of NGAL was suppressed by siRNA transfection in order to study the effect of lipocalin-2 on mentioned genes/proteins. The results showed that the expression of HO-1 and SOD 1, 2 enzymes were higher in cells expressing recombinant lipocalin-2 compared with the control cells. Although the expression of HO-1 was lower in NGAL silencing cells, the expression of SOD1 and SOD2 were higher. Our data suggest that NGAL is a potent inducer of HO-1 and somewhat SOD1 and SOD2 and it appears that part of antioxidant property of NGAL could be attributed to the induction of HO-1and SOD 1, 2. © Cell Stress Society International 2009

Sl-EDGE: Network Slicing at the Edge

Network slicing of multi-access edge computing (MEC) resources is expected to be a pivotal technology to the success of 5G networks and beyond. The key challenge that sets MEC slicing apart from traditional resource allocation problems is that edge nodes depend on tightly-intertwined and strictly-constrained networking, computation and storage resources. Therefore, instantiating MEC slices without incurring in resource over-provisioning is hardly addressable with existing slicing algorithms. The main innovation of this paper is Sl-EDGE, a unified MEC slicing framework that allows network operators to instantiate heterogeneous slice services (e.g., video streaming, caching, 5G network access) on edge devices. We first describe the architecture and operations of Sl-EDGE, and then show that the problem of optimally instantiating joint network-MEC slices is NP-hard. Thus, we propose near-optimal algorithms that leverage key similarities among edge nodes and resource virtualization to instantiate heterogeneous slices 7.5x faster and within 0.25 of the optimum. We first assess the performance of our algorithms through extensive numerical analysis, and show that Sl-EDGE instantiates slices 6x more efficiently then state-of-the-art MEC slicing algorithms. Furthermore, experimental results on a 24-radio testbed with 9 smartphones demonstrate that Sl-EDGE provides at once highly-efficient slicing of joint LTE connectivity, video streaming over WiFi, and ffmpeg video transcoding

The Role of Epidermal Growth Factor Receptor in Cancer and their Application for New Targeted Cancer Therapy

Epidermal Growth Factor Receptor (EGFR) has central role in cancer therapy because it causes tumour progression in many cases. The EGFR has seven ligands. Each factor that can block this binding, inhibits the intracellular signal transduction and prevents progression of the tumours. Immune system response is the most important factor for suppressing the initial stage of tumour growth and destroying some initial malignant cells, daily. On the other hand, tumours have different mechanisms to hide their antigens and escape from immune system responses. In contrary, tumours use some mechanisms to escape from immune system such as: 1) use of TGF-beta to initiate angiogenesis and immune suppression; 2) Induces Treg cell activation to modulate other immune cells; 3) secretion of the prostaglandin E2 to convert T cell into Treg. So, if a superantigen fused to one of the EGFR-ligands, causes the induction of immune system responses against the tumour cells. One of the new methods is based on the use of the fused super antigen with a ligand of the EGFR to inhibit ligand attaching to the EGFR and inducing immune system responses. To achieve this goal, we can block binding of EGFR to their ligands in the extracellular domain by fusing ligands with bacterial superantigens, toxins or cytokines of the viruses and plants that can induce immune system responses and kill malignant cells. So, the fused ligand can both block signal transduction and induce immune system response against malignant cells. In addition, with combining traditional drugs, high efficacy of the tumour treatment can be achieved. The aim of this review is to assess the mentioned strategy for targeting tumours

Positive selection of wharton�s jelly-derived CD105+ cells by MACS technique and their subsequent cultivation under suspension culture condition: A simple, versatile culturing method to enhance the multipotentiality of mesenchymal stem cells

Objective: Wharton�s jelly (WJ), an appropriate source of mesenchymal stem cells (MSCs), has been shown to have a wide array of therapeutic applications. However, the WJ-derived MSCs are very heterogeneous and have limited expression of pluripotency markers. Hence, improvement of their culture condition would promote the efficiency of WJ-MSCs. This study aims to employ a simple method of cultivation to obtain WJ-MSCs which express more pluripotency markers. Methods: CD105+ cells were separated by magnetic-associated (activated) cell sorting from umbilical cord mucous tissue. CD105+ cells were added to Methocult medium diluted in α-minimum essential medium (α-MEM) and seeded in poly(2-hydroxyethyl methacrylate) (poly-HEMA)-coated plates for suspension culture preparation. Differentiation capacity of isolated cells was evaluated in the presence of differentiation-inducing media. The expression of pluripotency markers such as Oct3/4, Nanog, and Sox2 was also analyzed by RT-PCR and western blot techniques. Moreover, immunocytochemistry was performed to detect alpha-smooth muscle actin (antigene) (α-SMA) protein. Results: WJ-MSCs grew homogeneously and formed colonies when cultured under suspension culture conditions (Non-adhesive WJ-MSCs). They maintained their growth ability in both adherent and suspension cultures for several passages. Non-adhesive WJ-MSCs expressed Oct3/4, Nanog, and Sox2 both at transcriptional and translational levels in comparison to those cultured in conventional adherent cultures. They also expressed α-SMA protein. Discussion: In this study, we isolated WJ-MSCs using a slightly modified culture condition. Our simple non-genetic method resulted in a homogeneous population of WJ-MSCs, which highly expressed pluripotency markers. Conclusion: In the future, more multipotent WJ-MSCs can be harnessed as a non-embryonic source of MSCs in MSC-based cell therapy. © W. S. Maney & Son Ltd 2015

Induction of multipotency in umbilical cord-derived mesenchymal stem cells cultivated under suspension conditions

Due to the limitations in the clinical application of embryonic stem cells (ESC) and induced pluripotent stem cells, mesenchymal stem cells (MSCs) are now much more interesting for cell-based therapy. Although MSCs have several advantages, they are not capable of differentiating to all three embryonic layers (three germ layers) without cultivation under specific induction media. Hence, improvement of MSCs for cell therapy purposes is under intensive study now. In this study, we isolated MSCs from umbilical cord tissue at the single-cell level, by treatment with trypsin, followed by cultivation under suspension conditions to form a colony. These colonies were trypsin resistant, capable of self-renewal differentiation to the three germ layers without any induction, and they were somewhat similar to ESC colonies. The cells were able to grow in both adherent and suspension culture conditions, expressed both the MSCs markers, especially CD105, and the multipotency markers, i.e., SSEA-3, and had a limited lifespan. The cells were expanded under simple culture conditions at the single-cell level and were homogenous. Further and complementary studies are required to understand how trypsin-tolerant mesenchymal stem cells are established. However, our study suggested non-embryonic resources for future cell-based therapy. © 2014 Cell Stress Society International