Helicase-primase inhibitors from Medshine Discovery Inc. (WO2018/127207 and WO2020/007355) for the treatment of herpes simplex virus infections - structure proposal for Phaeno Therapeutics drug candidate HN0037.

Helicase-primase is an interesting target for small-molecule therapy of herpes simplex virus (HSV) infections. With amenamevir already approved for varicella-zoster virus and with pritelivir's granted breakthrough therapy designation for the treatment of acyclovir-resistant HSV infections in immunocompromised patients, the target has sparked interest for me-too approaches. We describe the opportunities and limitations of the helicase-primase inhibitor patent portfolio from Phaeno Therapeutics and propose the structure of their drug candidate HN0037, which has been in-licensed from Medshine Discovery.

Assessing the developing pharmacotherapeutic landscape in hepatitis B treatment: a spotlight on drugs in phase II clinical trials.

INTRODUCTION: Functional cure, defined as sustained HBsAg seroclearance, is associated with favorable outcomes in chronic hepatitis B (CHB). While nucleos(t)ide analogues (NAs) are effective in suppressing HBV replication, NAs are unable to induce functional cure at high rates. A range of novel HBV antivirals, aiming to induce functional cure, are currently under development. AREAS COVERED: This article covered novel hepatitis B virus (HBV) antivirals that have entered phase II trials. Virus-directing agents covered include entry inhibitors, transcription inhibitors, RNA silencers, core protein allosteric modulators, noncompetitive polymerase inhibitors, and viral protein export inhibitors. Immunomodulators covered include innate immune stimulators, T-cell modulators, therapeutic vaccines, and monoclonal antibodies. Upcoming developmental directions would also be discussed. EXPERT OPINION: Among novel HBV antivirals, RNA silencers, viral protein export inhibitors (with pegylated interferon), and entry inhibitors (with pegylated interferon) appear to be effective in suppressing HBsAg and may even induce functional cure. The other virus-targeting agents have variable effects on HBV DNA, HBsAg, HBeAg, and HBcrAg. Immunomodulators have modest effects on HBsAg but may have important roles in combination therapy. Upcoming trials will answer important questions on ideal dosing, long-term drug effects, and efficacy of combination regimens.

Past and Future of Phage Therapy and Phage-Derived Proteins in Patients with Bone and Joint Infection.

Phage-derived therapies comprise phage therapy and the use of phage-derived proteins as anti-bacterial therapy. Bacteriophages are natural viruses that target specific bacteria. They were proposed to be used to treat bacterial infections in the 1920s, before the discovery and widespread over-commercialized use of antibiotics. Phage therapy was totally abandoned in Western countries, whereas it is still used in Poland, Georgia and Russia. We review here the history of phage therapy by focusing on bone and joint infection, and on the development of phage therapy in France in this indication. We discuss the rationale of its use in bacterial infection and show the feasibility of phage therapy in the 2020s, based on several patients with complex bone and joint infection who recently received phages as compassionate therapy. Although the status of phage therapy remains to be clarified by health care authorities, obtaining pharmaceutical-grade therapeutic phages (i.e., following good manufacturing practice guidelines or being "GMP-like") targeting bacterial species of concern is essential. Moreover, multidisciplinary clinical expertise has to determine what could be the relevant indications to perform clinical trials. Finally "phage therapy 2.0" has to integrate the following steps: (i) follow the status of phage therapy, that is not settled and defined; (ii) develop in each country a close relationship with the national health care authority; (iii) develop industrial-academic partnerships; (iv) create academic reference centers; (v) identify relevant clinical indications; (vi) use GMP/GMP-like phages with guaranteed quality bioproduction; (vii) start as salvage therapy; (vii) combine with antibiotics and adequate surgery; and (viii) perform clinical trials, to finally (ix) demonstrate in which clinical settings phage therapy provides benefit. Phage-derived proteins such as peptidoglycan hydrolases, polysaccharide depolymerases or lysins are enzymes that also have anti-biofilm activity. In contrast to phages, their development has to follow the classical process of medicinal products. Phage therapy and phage-derived products also have a huge potential to treat biofilm-associated bacterial diseases, and this is of crucial importance in the worldwide spread of antimicrobial resistance.

Development of surface engineered antigenic exosomes as vaccines for respiratory syncytial virus.

Respiratory syncytial virus (RSV) is one of the main pathogens associated with lower respiratory tract infections in infants and young children worldwide. Exosomes secreted by antigen presenting cells (APCs) can elicit immune responses by carrying major histocompatibility complex (MHC) class I molecules complexed with antigenic peptides and other co-stimulating factors. Therefore, we developed novel immunomagnetic nanographene particles to sequentially isolate, surface engineer, and release intact dendritic cell (DC) exosomes for use as a potential vaccine platform against RSV. The H-2Db-restricted, immunodominant peptides from RSV (M187-195 and NS161-75) were introduced to MHC-I on DC-derived exosomes to express peptide/MHC-I (pMHC-I) complexes. A mouse model of RSV infection was used to define the immunogenicity of surface engineered exosomes for activating virus-specific immune responses. Ex vivo assays demonstrated that engineered exosomes carrying RSV-specific peptides can elicit interferon-gamma (IFN-γ) production by virus-specific CD8+ T cells isolated from RSV-infected C57BL/6 mice. In vivo assays demonstrated that subcutaneous administration of both M187-195 and NS161-75 engineered exosomes to mice, with or without additional adjuvant, appeared safe and well tolerated, however, did not prime antigen-specific CD8+ T cell responses. Surface engineered exosomes are immunogenic and promising for further development as a vaccine platform.

Epstein Barr Virus: Development of Vaccines and Immune Cell Therapy for EBV-Associated Diseases.

Epstein-Barr virus (EBV) is the first human tumor virus discovered and is strongly implicated in the etiology of multiple lymphoid and epithelial cancers. Each year EBV associated cancers account for over 200,000 new cases of cancer and cause 150,000 deaths world-wide. EBV is also the primary cause of infectious mononucleosis, and up to 70% of adolescents and young adults in developed countries suffer from infectious mononucleosis. In addition, EBV has been shown to play a critical role in the pathogenesis of multiple sclerosis. An EBV prophylactic vaccine that induces neutralizing antibodies holds great promise for prevention of EBV associated diseases. EBV envelope proteins including gH/gL, gB and gp350 play key roles in EBV entry and infection of target cells, and neutralizing antibodies elicited by each of these proteins have shown to prevent EBV infection of target cells and markedly decrease EBV titers in the peripheral blood of humanized mice challenged with lethal dose EBV. Recent studies demonstrated that immunization with the combination of gH/gL, gB and/or gp350 induced markedly increased synergistic EBV neutralizing activity compared to immunization with individual proteins. As previous clinical trials focused on gp350 alone were partially successful, the inclusion of gH/gL and gB in a vaccine formulation with gp350 represents a promising approach of EBV prophylactic vaccine development. Therapeutic EBV vaccines have also been tested clinically with encouraging results. Immunization with various vaccine platforms expressing the EBV latent proteins EBNA1, LMP1, and/or LMP2 promoted specific CD4+ and CD8+ cytotoxic responses with anti-tumor activity. The addition of EBV envelope proteins gH/gL, gB and gp350 has the potential to increase the efficacy of a therapeutic EBV vaccine. The immune system plays a critical role in the control of tumors, and immune cell therapy has emerged as a promising treatment of cancers. Adoptive T-cell therapy has been successfully used in the prevention and treatment of post-transplant lymphoproliferative disorder. Chimeric antigen receptor T cell therapy and T cell receptor engineered T cell therapy targeting EBV latent proteins LMP1, LMP2 and/or EBNA1 have been in development, with the goal to increase the specificity and efficacy of treatment of EBV associated cancers.

Next-Generation Antibiotics, Bacteriophage Endolysins, and Nanomaterials for Combating Pathogens.

This review presents various strategies to fight causative agents of infectious diseases. Species-specific programmable RNA-containing antibiotics open up new possibilities for creating next-generation of personalized drugs based on microbiome editing and can serve as a new tool for selective elimination of pathogenic bacterial species while keeping intact the rest of microbiota. Another promising approach in combating bacterial infections is genome editing using the CRISPR-Cas systems. Expanding knowledge on the molecular mechanisms of innate immunity has been actively used for developing new antimicrobials. However, obvious risks of using antibiotic adjuvants aimed at activation of the host immune system include development of the autoimmune response with subsequent organ damage. To avoid these risks, it is essential to elucidate action mechanisms of the specific ligands and signal molecules used as components of the hybrid antibiotics. Bacteriophage endolysins are also considered as effective antimicrobials against antibiotic-resistant bacteria, metabolically inactive persisters, and microbial biofilms. Despite significant advances in the design of implants with antibacterial properties, the problem of postoperative infections still remains. Different nanomodifications of the implant surface have been designed to reduce bacterial contamination. Here, we review bactericidal, fungicidal, and immunomodulating properties of compounds used for the implant surface nanomodifications, such as silver, boron nitride nanomaterials, nanofibers, and nanogalvanic materials.

A 7-Amino Acid Peptide Mimic from Hepatitis C Virus Hypervariable Region 1 Inhibits Mouse Lung Th9 Cell Differentiation by Blocking CD81 Signaling during Allergic Lung Inflammation.

T helper (Th) cells orchestrate allergic lung inflammation in asthma pathogenesis. Th9 is a novel Th cell subset that mainly produces IL-9, a potent proinflammatory cytokine in asthma. A 7-amino acid peptide (7P) of the hypervariable region 1 (HVR1) of hepatitis C virus has been identified as an important regulator in the type 2 cytokine (IL-4, IL-5, and IL-13) immune response. However, it is unknown whether 7P regulates Th9 cell differentiation during ovalbumin- (OVA-) induced allergic lung inflammation. To address this, we studied wild-type mice treated with 7P and a control peptide in an in vivo mouse model of OVA-induced allergic inflammation and an in vitro cell model of Th9 differentiation, using flow cytometry, cytokine assays, and quantitative PCR. The binding of 7P to CD81 on naïve CD4+ T cells during lung Th9 differentiation was determined using CD81 overexpression and siRNA knockdown analyses. Administration of 7P significantly reduced Th9 cell differentiation after OVA sensitization and exposure. 7P also inhibited Th9 cell differentiation from naïve and memory CD4+ T cells in vitro. Furthermore, 7P inhibited the differentiation of human Th9 cells with high CD81 expression from naïve CD4+ T cells by blocking CD81 signaling. CD81 siRNA significantly reduced Th9 cell differentiation from naïve CD4+ T cells in vitro. Interestingly, CD81 overexpression in human naïve CD4+ T cells also enhanced Th9 development in vitro. These data indicate that 7P may be a good candidate for reducing IL-9 production in asthma.

Bacteriophages and Lysins in Biofilm Control.

To formulate the optimal strategy of combatting bacterial biofilms, in this review we update current knowledge on the growing problem of biofilm formation and its resistance to antibiotics which has spurred the search for new strategies to deal with this complication. Based on recent findings, the role of bacteriophages in the prevention and elimination of biofilm-related infections has been emphasized. In vitro, ex vivo and in vivo biofilm treatment models with single bacteriophages or phage cocktails have been compared. A combined use of bacteriophages with antibiotics in vitro or in vivo confirms earlier reports of the synergistic effect of these agents in improving biofilm removal. Furthermore, studies on the application of phage-derived lysins in vitro, ex vivo or in vivo against biofilm-related infections are encouraging. The strategy of combined use of phage and antibiotics seems to be different from using lysins and antibiotics. These findings suggest that phages and lysins alone or in combination with antibiotics may be an efficient weapon against biofilm formation in vivo and ex vivo, which could be useful in formulating novel strategies to combat bacterial infections. Those findings proved to be relevant in the prevention and destruction of biofilms occurring during urinary tract infections, orthopedic implant-related infections, periodontal and peri-implant infections. In conclusion, it appears that most efficient strategy of eliminating biofilms involves phages or lysins in combination with antibiotics, but the optimal scheme of their administration requires further studies.

EBV-miR-BHRF1-1 Targets p53 Gene: Potential Role in Epstein-Barr Virus Associated Chronic Lymphocytic Leukemia.

PURPOSE: The purpose of this study was to investigate the prognostic impact of Epstein-Barr virus (EBV)-microRNA (miRNA, miR)-BHRF1-1 with chronic lymphocytic leukemia (CLL) as well as role of EBV-miR-BHRF1-1 in p53 gene. MATERIALS AND METHODS: Quantitative reverse transcription-polymerase chain reaction and western blotting were used to quantify EBV-miR-BHRF1-1 and p53 expression in cultured CLL. RESULTS: p53 aberration was associated with the higher expression level of EBV-miR-BHRF1-1 (p < 0.001) which was also an independent prognostic marker for overall survival (p=0.028; hazard ratio, 5.335; 95% confidence interval, 1.193 to 23.846) in 97 newly-diagnosed CLL patients after adjusted with International Prognostic Index for patients with CLL. We identified EBV-miR-BHRF1-1 as a viral miRNA regulator of p53. EBV-miR-BHRF1-1 repressed luciferase reporter activity by specific interaction with the seed region within the p53 3'- untranslated region. Discordance of p53 messenger RNA and protein expression was associated with high EBV-miR-BHRF1-1 levels in CLL patients and cell lines. EBV-miR-BHRF1- 1 inhibition upregulated p53 protein expression, induced cell cycle arrest and apoptosis and decreased cell proliferation in cell lines. EBV-miR-BHRF1-1 mimics downregulated p53 protein expression, decreased cell cycle arrest and apoptosis, and induced cell proliferation in cell lines. CONCLUSION: This study supported the role of EBV-miR-BHRF1-1 in p53 regulation in vitro. Our results support the potential of EBV-miR-BHRF1-1 as a therapeutic target in EBV-associated CLL with p53 gene aberration.

Synthesis and Immunological Evaluation of Disaccharide Bearing MUC-1 Glycopeptide Conjugates with Virus-like Particles.

Mucin-1 (MUC1) is a highly attractive antigenic target for anticancer vaccines. Naturally existing MUC1 can contain multiple types of O-linked glycans, including the Thomsen-Friedenreich (Tf) antigen and the Sialyl Thomsen-nouveau (STn) antigen. In order to target these antigens as potential anticancer vaccines, MUC1 glycopeptides SAPDT*RPAP (T* is the glycosylation site) bearing the Tf and the STn antigen, respectively, have been synthesized. The bacteriophage Qß carrier is a powerful carrier for antigen delivery. The conjugates of MUC1-Tf and -STn glycopeptides with Qß were utilized to immunize immune-tolerant human MUC1 transgenic (MUC1.Tg) mice, which elicited superior levels of anti-MUC1 IgG antibodies with titers reaching over 2 million units. The IgG antibodies recognized a wide range of MUC1 glycopeptides bearing diverse glycans. Antibodies induced by Qß-MUC1-Tf showed strongest binding, with MUC1-expressing melanoma B16-MUC1 cells, and effectively killed these cells in vitro. Vaccination with Qß-MUC1-Tf first followed by tumor challenge in a lung metastasis model showed significant reductions of the number of tumor foci in the lungs of immunized mice as compared to those in control mice. This was the first time that a MUC1-Tf-based vaccine has shown in vivo efficacy in a tumor model. As such, Qß-MUC1 glycopeptide conjugates have great potential as anticancer vaccines.

LaSota Strain Expressing The Rabies Virus Glycoprotein (rL-RVG) Suppresses Gastric Cancer by Inhibiting the Alpha 7 Nicotinic Acetylcholine Receptor (α7 nAChR)/Phosphoinositide 3-Kinase (PI3K)/AKT Pathway.

BACKGROUND The recombinant avirulent Newcastle disease virus (NDV) LaSota strain expressing the rabies virus glycoprotein (rL-RVG) can induce much greater apoptosis than can NDV in gastric carcinoma cells, but the mechanisms involved remains unclear. MATERIAL AND METHODS The 2 gastric carcinoma cell lines were divided into the rL-RVG group, the NDV group, and the PBS group. MTT assay was used to detect and analyze cell viability. siRNA for alpha7-nAChR, alpha7-nAChR antagonist, or alpha7-nAChR agonist, AKT antagonist, and p-AKT agonist were used for pretreatment. The protein expressions of RVG, NDV, alpha7-nAChR, cleaved caspase-3, p-AKT, PI3K, Bcl-2, and Bax proteins were detected by Western blot assay. Immunofluorescence was used to detect expressions of alpha7-nAChR proteins. Light microscopy, flow cytometry, and TUNEL assay were used to assess apoptosis. RESULTS The results showed that 2 virus concentrations over 10³ dilution caused greater cell proliferation inhibition. rL-RVG treatment increased the expression of alpha7-nAChR, cleaved caspase-3, and Bax protein but decreased the expression of p-AKT, PI3K, and Bcl-2 protein. When the groups were pretreated with alpha7-nAChR antagonist, the alpha7-nAChR, cleaved caspase-3, and Bax protein expression increased, but the expression of p-AKT, PI3K, and Bcl-2 protein was clearly decreased. However, the results in the alpha7-nAChR agonist group were the opposite. When treated with the AKT antagonist, the result was the same as in the rL-RVG treatment group. The result in the AKT agonist group was the opposite of that in the AKT antagonist group. Compared with the NDV group, the results of light microscopy, FCM, and TUNEL assay showed that alpha7-nAChR antagonist significantly affected the apoptosis of gastric cancer cells in the rL-RVG group. CONCLUSIONS rL-RVG leads to much greater apoptosis through the alpha7-nAChR/PI3K/AKT pathway.

Bacteriophage gene products as potential antimicrobials against tuberculosis.

Tuberculosis (TB) is recognised as one of the most pressing global health threats among infectious diseases. Bacteriophages are adapted for killing of their host, and they were exploited in antibacterial therapy already before the discovery of antibiotics. Antibiotics as broadly active drugs overshadowed phage therapy for a long time. However, owing to the rapid spread of antibiotic resistance and the increasing complexity of treatment of drug-resistant TB, mycobacteriophages are being studied for their antimicrobial potential. Besides phage therapy, which is the administration of live phages to infected patients, the development of drugs of phage origin is gaining interest. This path of medical research might provide us with a new pool of previously undiscovered inhibition mechanisms and molecular interactions which are also of interest in basic research of cellular processes, such as transcription. The current state of research on mycobacteriophage-derived anti-TB treatment is reviewed in comparison with inhibitors from other phages, and with focus on transcription as the host target process.

Blockade of the NLRP3/Caspase-1 Axis Ameliorates Airway Neutrophilic Inflammation in a Toluene Diisocyanate-Induced Murine Asthma Model.

Multiple studies have addressed the vital role of Nod-like receptor protein 3(NLRP3)/caspase-1/IL-1ß signaling in asthma. Yet, the role of NLRP3/caspase-1 in toluene diisocyanate (TDI)-induced asthma is still obscure. The aim of this study is to investigate the role of the NLRP3/caspase-1 axis in TDI-induced asthma. Using an established murine model of TDI-induced asthma as described previously, we gave the asthmatic mice a highly selective NLRP3 inhibitor, MCC950, as well as the specific caspase-1 inhibitors VX-765 and Ac-YVAD-CHO for therapeutic purposes. Airway resistance was measured and bronchoalveolar lavage fluid was analyzed. Lungs were examined by histology, immunohistochemistry, Western blotting, and flow cytometry. TDI exposure elevated the expression of NLRP3 and caspase-1 that was coupled with increased airway hyperresponsiveness (AHR), neutrophil-dominated cell infiltration, pronounced goblet cell metaplasia, extensive collagen deposition, and increased TH2/TH17 responses. Both VX-765 and Ac-YVAD-CHO effectively inhibited the activation of caspase-1 in TDI-asthmatic mice that was accompanied by dramatic attenuation of AHR, airway inflammation, and airway remodeling, in addition to a decreased TH2 response and lower levels of IL-18 and IL-1ß. MCC950 blocked the activation of NLRP3 and downregulated protein expression of caspase-1, IL-1ß, and IL-18 in TDI-exposed mice. Furthermore, MCC950 remarkably alleviated AHR, airway inflammation, airway remodeling, and significantly suppressed TH2/TH17 responses. These findings suggested that blockade of the NLRP3/caspase-1 axis effectively prevents the progression of TDI-induced asthma and could be used as therapeutic targets for asthmatics.

The effect of combined drugs therapy on the course of clinical rabies infection in a murine model.

Rabies is a fatal disease of all mammals causing almost 60,000 human deaths every year. To date, there is no effective treatment of clinical rabies once the symptoms appear. Here, we describe the promising effect of combination therapy composed of molecules that target replication of the rabies virus (RV) at different stages of life cycle and molecules that inhibit some pathways of the innate host immune response accompanied by a blood-brain barrier opener on the outcome of RV infection. The study reports statistically significant extension of survival of mice treated with the drug cocktail containing T-705, ribavirin, interferon α/ß, caspase-1 inhibitor, TNF-α inhibitor, MAPKs inhibitor and HRIG compared to the survival of mice in the virus control group (p = 0.0312). Furthermore, the study points to the significant impact of interferon α/ß on the survival of RV-infected mice. We have shown a significant down regulation of pro-inflammatory molecules (caspase-1 and TNF-a) in the CNS in RV-infected mice treated with a combination of drugs including interferon α/ß.

Serpins: Development for Therapeutic Applications.

Serine protease inhibitors, or serpins, function as central regulators for many vital processes in the mammalian body, maintaining homeostasis for clot formation and breakdown, immune responses, lung function, and hormone or central nervous system activity, among many others. When serine protease activity or serpin-mediated regulation becomes unbalanced or dysfunctional, then severe disease states and pathogenesis can ensue. With serpinopathies, genetic mutations lead to inactive serpins or protein aggregation with loss of function. With other disorders, such as sepsis, atherosclerosis, cancer, obesity, and the metabolic syndrome, the thrombotic and thrombolytic cascades and/or inflammatory responses become unbalanced, with excess bleeding and clotting and upregulation of adverse immune responses. Returning overall balance can be engineered through introduction of a beneficial serpin replacement as a therapeutic or through blockade of serpins that are detrimental. Several drugs have been developed and are currently in use and/or in development both to replace dysfunctional serpins and to block adverse effects induced by aberrant protease or serpin actions.With this chapter, we provide a general overview of the development of a virus-derived serpin, Serp-1, and serpin reactive center loop (RCL) peptides, as therapeutics. Serp-1 is a virus-derived serpin developed as a new class of immune modulator. We will use the development of Serp-1 as a general introduction to serpin-based drug development.

US28: HCMV's Swiss Army Knife.

US28 is one of four G protein coupled receptors (GPCRs) encoded by human cytomegalovirus (HCMV). The US28 protein (pUS28) is a potent signaling molecule that alters a variety of cellular pathways that ultimately alter the host cell environment. This viral GPCR is expressed not only in the context of lytic replication but also during viral latency, highlighting its multifunctional properties. pUS28 is a functional GPCR, and its manipulation of multiple signaling pathways likely impacts HCMV pathogenesis. Herein, we will discuss the impact of pUS28 on both lytic and latent infection, pUS28-mediated signaling and its downstream consequences, and the influence this viral GPCR may have on disease states, including cardiovascular disease and cancer. We will also discuss the potential for and progress towards exploiting pUS28 as a novel therapeutic to combat HCMV.

Optimization of viral protein ratios for production of rAAV serotype 5 in the baculovirus system.

Recombinant adeno-associated virus (rAAV) has become the vector of choice for the development of novel human gene therapies. High-yield manufacturing of high-quality vectors can be achieved using the baculovirus expression vector system. However, efficient production of rAAV in this insect cell-based system requires a genetic redesign of the viral protein 1 (VP1) operon. In this study, we generated a library of rationally designed rAAV serotype 5 variants with modulations in the translation-initiation region of VP1 and investigated the potency of the resulting vectors. We found that the initiation strength at the VP1 translational start had downstream effects on the VP2/VP3 ratio. Excessive incorporation of VP3 into a vector type decreased potency, even when the VP1/VP2 ratio was in balance. Finally, we successfully generated a potent rAAV vector based on serotype 5 with a balanced VP1/VP2/VP3 stoichiometry.

In Vitro Characteristics of Phages to Guide 'Real Life' Phage Therapy Suitability.

The increasing problem of antibiotic-resistant pathogens has put enormous pressure on healthcare providers to reduce the application of antibiotics and to identify alternative therapies. Phages represent such an alternative with significant application potential, either on their own or in combination with antibiotics to enhance the effectiveness of traditional therapies. However, while phage therapy may offer exciting therapeutic opportunities, its evaluation for safe and appropriate use in humans needs to be guided initially by reliable and appropriate assessment techniques at the laboratory level. Here, we review the process of phage isolation and the application of individual pathogens or reference collections for the development of specific or "off-the-shelf" preparations. Furthermore, we evaluate current characterization approaches to assess the in vitro therapeutic potential of a phage including its spectrum of activity, genome characteristics, storage and administration requirements and effectiveness against biofilms. Lytic characteristics and the ability to overcome anti-phage systems are also covered. These attributes direct phage selection for their ultimate application as antimicrobial agents. We also discuss current pitfalls in this research area and propose that priority should be given to unify current phage characterization approaches.

Targeted transport of nanocarriers into brain for theranosis with rabies virus glycoprotein-derived peptide.

For successful theranosis of brain diseases, limited access of therapeutic molecules across blood-brain barrier (BBB) needs be overcome in brain delivery. Currently, peptide derivatives of rabies virus glycoprotein (RVG) have been exploited as delivery ligands to transport nanocarriers across BBB and specifically into the brain. The targeting peptides usually conjugate to the nanocarrier surface, and the cargoes, including siRNA, miRNA, DNA, proteins and small molecular chemicals, are complexed or encapsulated in the nanocarriers. The peptide ligand of the RVG-modified nanocarriers introduces the conjugated targeted-delivery into the brain, and the cargoes are involved in disease theranosis. The peptide-modified nanocarriers have been applied to diagnose and treat various brain diseases, such as glioma, Alzheimer's disease, ischemic injury, protein misfolding diseases etc. Since the targeting delivery system has displayed good biocompatibility and desirable therapeutic effect, it will raise a potential application in treating brain diseases.

RVG29-modified docetaxel-loaded nanoparticles for brain-targeted glioma therapy.

Gliomas are the most common malignant brain tumor, but treatment is limited by the blood-brain barrier (BBB), especially for chemotherapeutic drugs. Although some chemotherapy drugs can pass through the BBB, many of these agents are toxic to normal brain tissue. To maximize therapeutic effects, chemotherapeutic drugs must accumulate at the glioma site. In this study, a specific ligand (the RVG29 peptide) that can combine with acetylcholine receptors was conjugated to polyethylene glycol-modified poly-(d,l-lactide-co-glycolide) (PEG-PLGA) to develop a targeted carrier; preparation of the targeted docetaxel nanoparticles (DTX-NPs) was performed by the nanoprecipitation method. The NPs were approximately 110 nm and had smooth surfaces. Enzyme-linked immunoassay results showed that the amount of receptor on the surface of glioma cells was 2.04-fold higher than that of nonmalignant cells, which may promote accumulation of RVG29-modified NPs at the targeting site. NPs showed targeting properties for glioma cells compared with the non-targeting NPs in an in vitro cellular uptake test. Targeted NPs also showed better BBB penetration in an in vitro model. In vivo tests indicated that RVG29-PEG-PLGA-NPs could selectively accumulate in intracranial glioma tissue. In conclusion, these results indicated that the RVG29-modified NPs have potential efficacy for glioma therapy.