Lycium barbarum (Wolfberry) glycopeptide prevents stress-induced anxiety disorders by regulating oxidative stress and ferroptosis in the medial prefrontal cortex.

BACKGROUND: Lycium barbarum (Wolfberry) extract has been shown to be effective in neuroprotection against aging or neural injury. Knowledge of its potential roles and biological mechanisms in relieving mental disorders, however, remains limited. PURPOSE: To investigate the potency of Lycium barbarum glycopeptide (LbGp) in alleviating anxiety disorders and the related biological mechanisms. METHODS: LbGp was administrated to mice subjected to 14 days of chronic restrain stress (CRS) via the intragastric route. The anxiolytic effect was evaluated by a battery of behavioral assays. The morphology of neurons and glial cells was evaluated, and cortical neuronal calcium transients were recorded in vivo. The molecular mechanism of LbGp was also investigated. RESULTS: LbGp effectively relieved anxiety-like and depressive behaviors under CRS. Mechanistic studies further showed that LbGp treatment relieved oxidative stress and lipid peroxidation in the medial prefrontal cortex (mPFC). In particular, the ferroptosis pathway was inhibited by LbGp, revealing a previously unrecognized mechanism of the anxiolytic role of wolfberry extract. CONCLUSION: In summary, our results supported the future development of LbGp to prevent or ameliorate stress-induced anxiety disorders. Our work provides a promising strategy for early intervention for pateitents with mental disorders by applying natural plant extracts.

Postexposure Prophylaxis and Treatment of Bacillus anthracis Infections: A Systematic Review and Meta-analyses of Animal Models, 1947-2019.

BACKGROUND: Anthrax is endemic to many countries, including the United States. The causative agent, Bacillus anthracis, poses a global bioterrorism threat. Without effective antimicrobial postexposure prophylaxis (PEPAbx) and treatment, the mortality of systemic anthrax is high. To inform clinical guidelines for PEPAbx and treatment of B. anthracis infections in humans, we systematically evaluated animal anthrax treatment model studies. METHODS: We searched for survival outcome data in 9 scientific search engines for articles describing antimicrobial PEPAbx or treatment of anthrax in animals in any language through February 2019. We performed meta-analyses of efficacy of antimicrobial PEPAbx and treatment for each drug or drug combination using random-effects models. Pharmacokinetic/pharmacodynamic relationships were developed for 5 antimicrobials with available pharmacokinetic data. Monte Carlo simulations were used to predict unbound drug exposures in humans. RESULTS: We synthesized data from 34 peer-reviewed studies with 3262 animals. For PEPAbx and treatment of infection by susceptible B. anthracis, effective monotherapy can be accomplished with fluoroquinolones, tetracyclines, ß-lactams (including penicillin, amoxicillin-clavulanate, and imipenem-cilastatin), and lipopeptides or glycopeptides. For naturally occurring strains, unbound drug exposures in humans were predicted to adequately cover the minimal inhibitory concentrations (MICs; those required to inhibit the growth of 50% or 90% of organisms [MIC50 or MIC90]) for ciprofloxacin, levofloxacin, and doxycycline for both the PEPAbx and treatment targets. Dalbavancin covered its MIC50 for PEPAbx. CONCLUSIONS: These animal studies show many reviewed antimicrobials are good choices for PEPAbx or treatment of susceptible B. anthracis strains, and some are also promising options for combating resistant strains. Monte Carlo simulations suggest that oral ciprofloxacin, levofloxacin, and doxycycline are particularly robust choices for PEPAbx or treatment.

Glycophosphopeptical AM3 Food Supplement: A Potential Adjuvant in the Treatment and Vaccination of SARS-CoV-2.

The world is currently experiencing the coronavirus disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome-2 (SARS-CoV-2). Its global spread has resulted in millions of confirmed infections and deaths. While the global pandemic continues to grow, the availability of drugs to treat COVID-19 infections remains limited to supportive treatments. Moreover, the current speed of vaccination campaigns in many countries has been slow. Natural substrates with biological immunomodulatory activity, such as glucans, may represent an adjuvant therapeutic agent to treat SARS-CoV-2. AM3, a natural glycophosphopeptical, has previously been shown to effectively slow, with no side effects, the progression of infectious respiratory diseases by regulating effects on innate and adaptive immunity in experimental models. No clinical studies, however, exist on the use of AM3 in SARS-CoV-2 infected patients. This review aims to summarize the beneficial effects of AM3 on respiratory diseases, the inflammatory response, modulation of immune response, and attenuation of muscle. It will also discuss its potential effects as an immune system adjuvant for the treatment of COVID-19 infections and adjuvant for SARS-CoV-2 vaccination.

Genomic-Led Discovery of a Novel Glycopeptide Antibiotic by Nonomuraea coxensis DSM 45129.

Glycopeptide antibiotics (GPAs) are last defense line drugs against multidrug-resistant Gram-positive pathogens. Natural GPAs teicoplanin and vancomycin, as well as semisynthetic oritavancin, telavancin, and dalbavancin, are currently approved for clinical use. Although these antibiotics remain efficient, emergence of novel GPA-resistant pathogens is a question of time. Therefore, it is important to investigate the natural variety of GPAs coming from so-called "rare" actinobacteria. Herein we describe a novel GPA producer-Nonomuraea coxensis DSM 45129. Its de novo sequenced and completely assembled genome harbors a biosynthetic gene cluster (BGC) similar to the dbv BGC of A40926, the natural precursor to dalbavancin. The strain produces a novel GPA, which we propose is an A40926 analogue lacking the carboxyl group on the N-acylglucosamine moiety. This structural difference correlates with the absence of dbv29-coding for an enzyme responsible for the oxidation of the N-acylglucosamine moiety. Introduction of dbv29 into N. coxensis led to A40926 production in this strain. Finally, we successfully applied dbv3 and dbv4 heterologous transcriptional regulators to trigger and improve A50926 production in N. coxensis, making them prospective tools for screening other Nonomuraea spp. for GPA production. Our work highlights genus Nonomuraea as a still untapped source of novel GPAs.

From Therapeutic Drug Monitoring to Model-Informed Precision Dosing for Antibiotics.

Therapeutic drug monitoring (TDM) and model-informed precision dosing (MIPD) have evolved as important tools to inform rational dosing of antibiotics in individual patients with infections. In particular, critically ill patients display altered, highly variable pharmacokinetics and often suffer from infections caused by less susceptible bacteria. Consequently, TDM has been used to individualize dosing in this patient group for many years. More recently, there has been increasing research on the use of MIPD software to streamline the TDM process, which can increase the flexibility and precision of dose individualization but also requires adequate model validation and re-evaluation of existing workflows. In parallel, new minimally invasive and noninvasive technologies such as microneedle-based sensors are being developed, which-together with MIPD software-have the potential to revolutionize how patients are dosed with antibiotics. Nonetheless, carefully designed clinical trials to evaluate the benefit of TDM and MIPD approaches are still sparse, but are critically needed to justify the implementation of TDM and MIPD in clinical practice. The present review summarizes the clinical pharmacology of antibiotics, conventional TDM and MIPD approaches, and evidence of the value of TDM/MIPD for aminoglycosides, beta-lactams, glycopeptides, and linezolid, for which precision dosing approaches have been recommended.

Combinations of (lipo)glycopeptides with ß-lactams against MRSA: susceptibility insights.

BACKGROUND: Increasing application of vancomycin due to the high prevalence of MRSA infections has led to the emergence of vancomycin intermediate-resistant Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA). Consequently, the need for alternative therapies that target MRSA has become evident. OBJECTIVES: To evaluate the synergy between (lipo)glycopeptides (LGP/GPs) (vancomycin, teicoplanin, telavancin, dalbavancin and oritavancin) and ß-lactams (ceftaroline, cefepime, cefazolin and oxacillin) against MRSA, hVISA, VISA and daptomycin non-susceptible (DNS) phenotypes. METHODS: Twenty randomly selected clinical MRSA strains (i.e. 5 MRSA, 5 hVISA, 5 VISA and 5 DNS) were assessed versus LGP/GPs alone and LGP/GPs in combination with ß-lactams for MICs. Although verification of antibiotic potency against bacterial strains is assessed by the microbroth dilution (MBD) MIC method recommended by the CLSI, some antibiotics need modified assay conditions in order to demonstrate their optimal activity. RESULTS: Addition of ß-lactams reduced MIC values of LGP/GPs against all strains (up to 160-fold reduction). In general, LGPs (dalbavancin, oritavancin and telavancin) were more active (significant differences in MIC values, up to 8-fold) compared with vancomycin and teicoplanin. The majority of these combinations were bactericidal and superior to any single agent. CONCLUSIONS: This report has examined the susceptibility patterns of LGP/GPs and their combination with ß-lactams. Of interest, the impact of susceptibility tests (in terms of MIC plates and their surface area) on the synergistic activity in 24 h time-kill experiments was apparent for LGPs. Further clinical research is required to investigate synergy with LGP/GPs and ß-lactams against these Staphylococcus strains.

Evaluation of the Effect of Daptomycin, a Glycopeptide Agent, on Intact Intervertebral Disc Tissue.

AIM: To evaluate the effects of pre- and intra-operatively administered daptomycin (DAP) on the intact human primary intervertebral disc tissue cells. MATERIAL AND METHODS: Primary cell cultures were established using tissues obtained through decompressive laminectomy, traumatic intervertebral disc herniation excision, and posterior transpedicular stabilization. Non-drug-administered samples were used as a control group. The samples treated with DAP formed the study group. Molecular assays for proliferation and gene expression were performed. The obtained data were evaluated statistically, and results with a value of p < 0.05 were accepted as significant. RESULTS: While no reduction was observed in the proliferation, the gene expression of intact intervertebral disc tissue cells was time-dependently decreased compared to the control group, and these results were reported to be statistically significant. CONCLUSION: This study observed the effect that a pharmaceutical preparation, which was used on intervertebral disc tissue before and after the operation, had on normal, healthy, and intact tissue. It concludes that alterations in the expression of genes involved in the anabolic and/or catabolic process, even in adjacent healthy tissue, may slow down the healing process of the damaged tissue or cause undesired cell differentiation.

Study on the Structure of Ginseng Glycopeptides with Anti-Inflammatory and Analgesic Activity.

Panax ginseng is well known for its medicinal functions. As a class of important compound of ginseng, ginsenoside is widely studied around the world. In addition, ginseng glycopeptides also showed good biological activity, but researches in this field are rarely reported. In this study, ginseng glycopeptides (Gg) were first prepared from Panax ginseng by reflux extracted with 85% ethanol and the following purification with Sephadex G-15 column. Then, the inflammatory pain models induced by carrageenan and the rat pain models induced by Faure Marin were established for research on mechanism of analgesic activities. It is showed that Gg had an obvious inhibiting effect on inflammation and a significant reduction on the Malondialdehyde (MDA) of inflammatory foot tissue. And there were significant differences between moderate to high dose of Gg and model group in Interleukin 1ß (IL-1ß), Interleukin 2 (IL-2), Interleukin 4 (IL-4), Tumor necrosis factor α (TNF-α) and Histamine. The two models can be preliminarily determined that the analgesic effect of Gg may be peripheral, which mechanism may be related to the dynamic balance between proinflammatory cytokines (TNF-α, IL-1ß) and anti-inflammatory cytokines (IL-2, IL-4, and Interleukin 10 (IL-10)). A series of methods were used to study Gg in physical-chemical properties and linking mode of glycoside. The high-resolution mass spectrometry was used for identification of the structure of Gg. Moreover, the structure of 20 major Gg were investigated and identified. The structural analysis of Gg was benefit for the next study on structure-activity relationship.

The improvement of M1 polarization in macrophages by glycopeptide derived from Ganoderma lucidum.

Ganoderma lucidum (Fr.) Karst (Ganodermataceae) is a medicinal mushroom that has been extensively used in China for centuries to promote longevity and improve vigor without significant adverse effects. There is continuous interest in the bioactive properties of G. lucidum in view of its newly developed popularity in other regions besides Asia, such as Europe. Glycopeptide derived from G. lucidum (Gl-PS) is one of the main effective components isolated from this mushroom. The Gl-PS has been demonstrated pleiotropic with many bioactivities including immunomodulatory and antitumor effects. Macrophages are important cells involved in innate and adaptive immunity. Classically activated macrophages (M1) and alternatively activated macrophages (M2), with their different roles, display distinct cytokine profiles: M1 preferentially produces TNF-α, IL-6, and IL-12; conversely, M2 generates more IL-10 and arginase. Gl-PS might have the potential to promote macrophage M1 polarization by lipopolysaccharide (LPS). In this study, LPS was used to induce the M1 polarization. It was shown that the level of the TNF-α, IL-6, and IL-12 were increased and the IL-10 and arginase I were decreased in the polarized M1 macrophages after application of Gl-PS compared to the control. The results indicated the potential of Gl-PS to promote M1 polarization vs M2, with the health beneficial understanding of the bioactivities of Gl-PS.

Evaluation of Antibiotics Active against Methicillin-Resistant Staphylococcus aureus Based on Activity in an Established Biofilm.

We used in vitro and in vivo models of catheter-associated biofilm formation to compare the relative activity of antibiotics effective against methicillin-resistant Staphylococcus aureus (MRSA) in the specific context of an established biofilm. The results demonstrated that, under in vitro conditions, daptomycin and ceftaroline exhibited comparable activity relative to each other and greater activity than vancomycin, telavancin, oritavancin, dalbavancin, or tigecycline. This was true when assessed using established biofilms formed by the USA300 methicillin-resistant strain LAC and the USA200 methicillin-sensitive strain UAMS-1. Oxacillin exhibited greater activity against UAMS-1 than LAC, as would be expected, since LAC is an MRSA strain. However, the activity of oxacillin was less than that of daptomycin and ceftaroline even against UAMS-1. Among the lipoglycopeptides, telavancin exhibited the greatest overall activity. Specifically, telavancin exhibited greater activity than oritavancin or dalbavancin when tested against biofilms formed by LAC and was the only lipoglycopeptide capable of reducing the number of viable bacteria below the limit of detection. With biofilms formed by UAMS-1, telavancin and dalbavancin exhibited comparable activity relative to each other and greater activity than oritavancin. Importantly, ceftaroline was the only antibiotic that exhibited greater activity than vancomycin when tested in vivo in a murine model of catheter-associated biofilm formation. These results emphasize the need to consider antibiotics other than vancomycin, most notably, ceftaroline, for the treatment of biofilm-associated S. aureus infections, including by the matrix-based antibiotic delivery methods often employed for local antibiotic delivery in the treatment of these infections.

Oritavancin: A Novel Lipoglycopeptide.

OBJECTIVE: To review the pharmacology, pharmacokinetics, drug interactions, microbiologic profile, dosage and administration, safety, clinical efficacy, and potential place in therapy for the new lipoglycopetide, oritavancin. DATA SOURCES: MEDLINE and PubMed searches of available literature in English were conducted for oritavancin. Principal supplementary sources include the Food and Drug Administration (FDA) package insert, and FDA/European Medicines Agency guidances on acute bacterial skin and skin structure infections (ABSSSI). STUDY SELECTION AND DATA EXTRACTION: Information from all stages of clinical development was evaluated to provide an overview of oritavancin, from in vitro susceptibility, to early human studies, to the latter stages of clinical trials. DATA SYNTHESIS: Oritavancin is a lipoglycopeptide antibiotic that has a mechanism of action and broad-spectrum gram-positive coverage similar to other glycopeptides. Compared with other glycopeptides, oritavancin minimum inhibitory concentrations tend to be lower. Oritavancin also has coverage against glycopeptide-resistant gram-positive organisms. Oritavancin does not require dose adjustment for mild-to-moderate hepatic or renal impairment, and its prolonged half-life of 245 hours allows for a one-time administration in the treatment of ABSSSI. In phase 2 and 3 clinical trials, oritavancin was shown to be well-tolerated in addition to being noninferior to vancomycin for the treatment of ABSSSI. The most common side effects experienced were gastrointestinal in nature. CONCLUSIONS: Oritavancin was approved by FDA for the treatment of ABSSSI in August 2014 and is marketed under the trade name Orbactiv. Its reduced dosing and monitoring requirements and efficacy against resistant gram-positive pathogens provide a unique profile that distinguishes it from current options in the treatment of ABSSSI.

The antimicrobial peptide sublancin ameliorates necrotic enteritis induced by Clostridium perfringens in broilers.

Sublancin is an antimicrobial peptide produced by 168 containing 37 amino acids. The objective of this study was to investigate its inhibitory efficacy against both in vitro and in vivo. In the in vitro study, we determined that sublancin had a minimum inhibitory concentration of 8 µM against , which was much higher than the antibiotic lincomycin (0.281 µM). Scanning electron microscopy showed that sublancin damaged the morphology of . The in vivo study was conducted on broilers for a 28-d period using a completely randomized design. A total of 252 chickens at 1 d of age were randomly assigned to 1 of 6 treatments including an uninfected control; an infected control; 3 infected groups supplemented with sublancin at 2.88, 5.76, or 11.52 mg activity/L of water; and an infected group supplemented with lincomycin at 75 mg activity/L of water (positive control). Necrotic enteritis was induced in the broilers by oral inoculation of on d 15 through 21. Thereafter, the sublancin or lincomycin were administered fresh daily for a period of 7 days. The challenge resulted in a significant decrease in ADG ( < 0.05) and a remarkable deterioration in G:F ( < 0.05) during d 15 to 21 of the experiment. There was a sharp increase of numbers in the cecum ( < 0.05). The addition of sublancin or lincomycin reduced caecal counts ( < 0.05). The counts had a tendency to decrease in the lincomycin treatment ( = 0.051) but were the highest in the sublancin treatment (5.76 mg activity/L of water). A higher villus height to crypt depth ratio in the duodenum and jejunum as well as a higher villus height in the duodenum were observed in broilers treated with sublancin or lincomycin ( < 0.05) compared with infected control broilers. It was observed that sublancin and lincomycin decreased IL-1ß, IL-6, and tumor necrosis factor-α levels ( < 0.05) in the ileum compared with the infected control. In conclusion, although sublancin's minimum inhibitory concentration is much higher than lincomycin in vitro, less sublancin is needed to control necrotic enteritis induced by in vivo than lincomycin. These novel findings indicate that sublancin could be used as a potential antimicrobial agent to control necrotic enteritis.

Oritavancin: a review in acute bacterial skin and skin structure infections.

Oritavancin (Orbactiv(®)) is a new generation lipoglycopeptide approved for use in adult patients with acute bacterial skin and skin structure infections (ABSSSI). It is administered as a single 1200 mg intravenous infusion over 3 h. In phase 3 trials in adult patients with ABSSSI, oritavancin was noninferior to vancomycin in terms of a composite outcome (cessation of spreading or reduction in the size of the baseline lesion, absence of fever and no rescue antibacterials required; primary endpoint) assessed at an US FDA-recommended early timepoint of 48-72 h after initiation of treatment. Oritavancin was also noninferior to vancomycin in terms of a ≥20 % reduction in the baseline lesion size at the early timepoint and clinical cure rate 7-14 days after the end of treatment. Oritavancin was generally well tolerated in the phase 3 trials, with most treatment-emergent adverse reactions being mild in severity. The most common adverse events occurring in oritavancin recipients were nausea, headache, vomiting, limb and subcutaneous abscesses, and diarrhoea. Oritavancin offers a number of potential advantages, including a convenient single dose treatment that may shorten or eliminate hospital stays, a reduction in healthcare resource utilization and cost, no need for dosage adjustment in patients with mild to moderate hepatic or renal impairment, no need for therapeutic drug monitoring, and elimination of compliance concerns. Therefore, oritavancin is a useful treatment option for adults with ABSSSI.

Dalbavancin and Oritavancin: An Innovative Approach to the Treatment of Gram-Positive Infections.

Health care-associated infections, especially those caused by multidrug-resistant gram-positive organisms, such as methicillin-resistant Staphylococcus aureus (MRSA), are a growing public health threat. In 2014, the U.S. Food and Drug Administration approved two new lipoglycopeptides, oritavancin and dalbavancin, for the treatment of acute bacterial skin and skin structure infections. The rationale for the development of these antimicrobials was partly to aid in the battle against vancomycin resistance in both Staphylococcus and Enterococcus. Considered a subclass of the glycopeptide antibiotics, the new lipoglycopeptides have similar mechanisms of action of binding to the carboxyl terminal d-alanyl-d-alanine residue of the growing peptide chains but differ from their parent glycopeptides by the addition of lipophilic tails. This addition allows for these agents to have prolonged half-lives, giving them unique dosing profiles. In addition, by concentrating at the site of action, they have increased potency against MRSA compared with vancomycin, the current mainstay of therapy. In this review, we focus on comparing and contrasting these two new agents with regard to their pharmacology, mechanisms of action, spectrum of activity, safety profiles, dosage and administration, and drug and laboratory interactions, and we review the clinical trials evaluating their use.

[Cloxacillin-susceptible Staphylococcus aureus with high MIC to glycopeptides. Ever we use cloxacillin?]. / Staphylococcus aureus sensible a cloxacilina con CMI elevada a glucopéptidos. ¿Ponemos siempre cloxacilina?

Staphylococcus aureus infections are yet an important cause of morbidity and mortality despite of numerous effective anti-staphylococcal antibiotics available. There has been an increasing incidence of methicillin-resistant strains which might have led to a wider use of vancomycin. This seems to ride alongside a covert progressive increase of S. aureus vancomycin minimum inhibitory concentration. In this way, the emergence of vancomycin-intermediate S. aureus (VISA) strains and heteroresistant-VISA has raised concern for the scarcity of alternative treatment options. Equally alarming, though fortunately less frequent, is the emergence of vancomycin-resistant S. aureus. Ultimately, various debate issues have arisen regarding the emergence of S. aureus strains with decreased vancomycin susceptibility, within the range still considered sensitive. These strains have shown a different clinical behaviour regardless of vancomycin use, both in methicillin resistant and sensitive S. aureus. The emergence of increasing vancomycin-resistance in S. aureus isolates, has stirred up the basis of therapeutic approach in staphylococcal infections. There is yet much to explore to better define the impact of higher vancomycin minimum inhibitory concentration in staphylococcal infections.

Novel proline-hydroxyproline glycopeptides from the dandelion (Taraxacum officinale Wigg.) flowers: de novo sequencing and biological activity.

Two novel homologous peptides named ToHyp1 and ToHyp2 that show no similarity to any known proteins were isolated from Taraxacum officinale Wigg. flowers by multidimensional liquid chromatography. Amino acid and mass spectrometry analyses demonstrated that the peptides have unusual structure: they are cysteine-free, proline-hydroxyproline-rich and post-translationally glycosylated by pentoses, with 5 carbohydrates in ToHyp2 and 10 in ToHyp1. The ToHyp2 peptide with a monoisotopic molecular mass of 4350.3Da was completely sequenced by a combination of Edman degradation and de novo sequencing via top down multistage collision induced dissociation (CID) and higher energy dissociation (HCD) tandem mass spectrometry (MS(n)). ToHyp2 consists of 35 amino acids, contains eighteen proline residues, of which 8 prolines are hydroxylated. The peptide displays antifungal activity and inhibits growth of Gram-positive and Gram-negative bacteria. We further showed that carbohydrate moieties have no significant impact on the peptide structure, but are important for antifungal activity although not absolutely necessary. The deglycosylated ToHyp2 peptide was less active against the susceptible fungus Bipolaris sorokiniana than the native peptide. Unique structural features of the ToHyp2 peptide place it into a new family of plant defense peptides. The discovery of ToHyp peptides in T. officinale flowers expands the repertoire of molecules of plant origin with practical applications.

Modulation of TNF-α, TNF-α receptors and IL-6 after treatment with AM3 in professional cyclists.

AIM: Changes in IL-6, TNF-α, and TNF-α receptors - sTNFRI and sTNFRII - were evaluated in a group of professional cyclists treated with immunomodulator AM3 (Inmunoferón®) for 6 months of training and competition. METHODS: Sixteen male professional cyclists with a similar training program participated in the study which was designed as a randomized, placebo-controlled, double-blind clinical trial. Venous blood samples were collected in basal conditions, before beginning the supplementation program, and after 90 and 180 days of training and competition season. RESULTS: No significant differences in biochemical parameters or in IL-6 were evidenced between placebo and AM3-treated groups throughout the study. Plasma TNF-α levels significantly decreased (P<0.05) after 90 days of training in the AM3 treated group. TNF-α receptors increased during training season in both placebo and AM3 treated groups, although the increase was significantly higher (P<0.05) in the AM3 group with respect to the placebo group. CONCLUSION: The changes produced by regular training and competition were modified throughout the season by AM3 treatment which could reduce the inflammatory response to excessive exercise.

Oritavancin: first global approval.

Oritavancin (Orbactiv(®)) is a lipoglycopeptide antibacterial drug with activity against Gram-positive bacteria developed by The Medicines Company as a single-dose treatment for acute bacterial skin and skin structure infections (ABSSSI). The drug received its first global approval for this indication in the US in August 2014, and is under regulatory review in the EU. This article summarises the milestones in the development of oritavancin leading to this first approval for the treatment of ABSSSIs caused by Gram-positive bacteria.

Inhibition of IgE binding to cross-reactive carbohydrate determinants enhances diagnostic selectivity.

BACKGROUND: Allergy diagnosis by determination of allergen-specific IgE is complicated by clinically irrelevant IgE, of which the most prominent example is IgE against cross-reactive carbohydrate determinants (CCDs) that occur on allergens from plants and insects. Therefore, CCDs cause numerous false-positive results. Inhibition of CCDs has been proposed as a remedy, but has not yet found its way into the routine diagnostic laboratory. We sought to provide a simple and affordable procedure to overcome the CCD problem. METHODS: Serum samples from allergic patients were analysed for allergen-specific IgEs by different commercial tests (from Mediwiss, Phadia and Siemens) with and without a semisynthetic CCD blocker with minimized potential for nonspecific interactions that was prepared from purified bromelain glycopeptides and human serum albumin. RESULTS: Twenty two per cent of about 6000 serum samples reacted with CCD reporter proteins. The incidence of anti-CCD IgE reached 35% in the teenage group. In patients with anti-CCD IgE, application of the CCD blocker led to a clear reduction in read-out values, often below the threshold level. A much better correlation between laboratory results and anamnesis and skin tests was achieved in many cases. The CCD blocker did not affect test results where CCDs were not involved. CONCLUSION: Eliminating the effect of IgEs directed against CCDs by inhibition leads to a significant reduction in false-positive in vitro test results without lowering sensitivity towards relevant sensitizations. Application of the CCD blocker may be worthwhile wherever natural allergen extracts or components are used.

Identifying producers of antibacterial compounds by screening for antibiotic resistance.

Microbially derived natural products are major sources of antibiotics and other medicines, but discovering new antibiotic scaffolds and increasing the chemical diversity of existing ones are formidable challenges. We have designed a screen to exploit the self-protection mechanism of antibiotic producers to enrich microbial libraries for producers of selected antibiotic scaffolds. Using resistance as a discriminating criterion we increased the discovery rate of producers of both glycopeptide and ansamycin antibacterial compounds by several orders of magnitude in comparison with historical hit rates. Applying a phylogeny-based screening filter for biosynthetic genes enabled the binning of producers of distinct scaffolds and resulted in the discovery of a glycopeptide antibacterial compound, pekiskomycin, with an unusual peptide scaffold. This strategy provides a means to readily sample the chemical diversity available in microbes and offers an efficient strategy for rapid discovery of microbial natural products and their associated biosynthetic enzymes.