Pharmacokinetics and Disposition of Heparin-Binding Growth Factor Midkine Antisense Oligonucleotide Nanoliposomes in Experimental Animal Species and Prediction of Human Pharmacokinetics Using a Physiologically Based Pharmacokinetic Model.

Encapsulating the antisense oligonucleotide drug MK-ASODN with nanoliposomes greatly improved its potency and targeting to the heparin-binding growth factor midkine. The disposition and pharmacokinetic (PK) parameters of MK-ASODN nanoliposomes were studied in monkeys and rats, and the human PK parameters were predicted based on preclinical data using a physiologically based pharmacokinetic (PBPK) model. Following intravenous injection, the drug plasma concentration rapidly declined in a multiexponential manner, and the drug was rapidly transferred to tissues from the circulation.

Synthesis of hydrazide-functionalized hydrophilic polymer hybrid graphene oxide for highly efficient N-glycopeptide enrichment and identification by mass spectrometry.

Protein N-glycosylation is one of the most important post-translational modifications, participating in many key biological and pathological processes. Large-scale and precise identification of N-glycosylated proteins and peptides is especially beneficial for understanding their biological functions and for discovery of new clinical biomarkers and therapeutic drug targets. However, protein N-glycosylation is microheterogeneous and low abundant in living organisms, therefore specific enrichment of N-glycosylated proteins/peptides before mass spectrometry analysis is a prerequisite.

The improved efficacy of Sifuvirtide compared with enfuvirtide might be related to its selectivity for the rigid biomembrane, as determined through surface plasmon resonance.

Most mechanistic studies on human immunodeficiency virus (HIV) peptide fusion inhibitors have focused on the interactions between fusion inhibitors and viral envelope proteins. However, the interactions of fusion inhibitors with viral membranes are also essential for the efficacy of these drugs. Here, we utilized surface plasmon resonance (SPR) technology to study the interactions between the HIV fusion inhibitor peptides sifuvirtide and enfuvirtide and biomembrane models.

IBI302, a promising candidate for AMD treatment, targeting both the VEGF and complement system with high binding affinity in vitro and effective targeting of the ocular tissue in healthy rhesus monkeys.

Uncontrolled activation of complement and upregulation of vascular endothelial growth factor (VEGF) play fundamental roles in age-related macular degeneration (AMD). However, most drugs used to treat AMD focus on a single target, and the percentage of effectively treated patients in clinical practice needs to be improved. Therefore, novel AMD treatment approaches are needed.

Comparative pharmacokinetics and pharmacodynamics of a PEGylated recombinant human growth hormone and daily recombinant human growth hormone in growth hormone-deficient children.

Objective: Recombinant human growth hormone (rhGH) replacement therapy in children generally requires daily subcutaneous (sc) injections, which may be inconvenient for patients. Jintrolong® is a PEGylated rhGH with the purpose of weekly sc injections. The aim of the current study was to examine the pharmacokinetics, pharmacodynamics, safety, and tolerability of multiple sc doses of Jintrolong® vs daily doses of rhGH.

A novel stearic acid-modified hirudin peptidomimetic with improved pharmacokinetic properties and anticoagulant activity.

A novel hirudin isoform 3 mimetic peptide, named peptide S2, has been prepared by introduction of a stearic acid modification. Peptide S2 exhibited superior inhibitory activity to hirulog-1 (Bivariludin) and showed significantly higher anticoagulant potency in vivo. Peptide S2 elevated the thrombin time, prothrombin time and activated partial thromboplastin time of rat and human plasma more efficiently than hirulog-1 and the unmodified form of peptide S2 (peptide 1).

Real-Time Monitoring of Catheter-Related Biofilm Infection in Mice.

This study was done to establish a mouse model for catheter-related biofilm infection suitable to bioluminescence imaging (BLI). Biofilm formation of Pseudomonas aeruginosa (P. aeruginosa) Xen5 grown on catheter disks in vitro and in an implanted mouse model was real-time monitored during a 7-day study period using BLI.

Targeted LC-MS quantification of intact TAT-fusion therapeutics: a case study.

Background: While HIV-1 TAT peptide-conjugation shows great promise on improving intracellular delivery of biotherapeutics in vitro and in vivo, quantification of TAT-fusion therapeutics in biological matrices represents a daunting challenge.

Materials & Methods: A sensitive MS approach for accurate quantification of intact TAT-fusion protein/polypeptide in plasma was developed. i) A semi-automated 96-well ion-exchange solid phase extraction was developed; ii) a rapid LC separation on C4 was devised; iii) a TAT-fusion analog was constructed as internal standard.

Pharmacokinetics of sifuvirtide in treatment-naive and treatment-experienced HIV-infected patients.

The pharmacokinetics assessment in two clinical studies of sifuvirtide (a novel HIV fusion inhibitor) was first reported in Chinese HIV patients. Nineteen treatment-naive HIV patients were treated with s.c.

The induction of prolonged myelopoietic effects in monkeys by GW003, a recombinant human granulocyte colony-stimulating factor genetically fused to recombinant human albumin.

GW003, a genetic fusion protein of human serum albumin and granulocyte colony-stimulating factor (G-CSF), was developed based on a novel strategy for producing long-acting proteins. The purpose of this study was to evaluate the hematologic, pharmacokinetic, and toxicokinetic effects of GW003 on cynomolgus monkeys. We show that following a single subcutaneous administration of GW003, the absolute neutrophil count increased significantly compared with monkeys that received only the vehicle, and the magnitude of the neutrophilic response to GW003 was dose dependent.

Bioluminescent tracking of colonization and clearance dynamics of plasmid-deficient Yersinia pestis strains in a mouse model of septicemic plague.

Yersinia pestis 201 contains 4 plasmids pPCP1, pMT1, pCD1 and pCRY, but little is known about the effects of these plasmids on the dissemination of Y. pestis. We developed a plasmid-based luxCDABE bioreporter in Y.

An LC-MS/MS assay to determine plasma pharmacokinetics of cyclic thymic hexapeptide (cTP6) in rhesus monkeys.

A robust and simple method for absolute quantification of a novel bidirectional immunomodulatory drug candidate, cyclic thymic hexapeptide (cTP6), in rhesus monkey plasma was developed and validated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Plasma proteins were precipitated by adding four volumes of acetonitrile. Peptides in the supernatant were separated by liquid chromatography on an Agilent Zorbax Eclipse Plus-C18 chromatographic column with gradient elution using 0.

Tumor endothelium marker-8 based decoys exhibit superiority over capillary morphogenesis protein-2 based decoys as anthrax toxin inhibitors.

Anthrax toxin is the major virulence factor produced by Bacillus anthracis. The toxin consists of three protein subunits: protective antigen (PA), lethal factor, and edema factor. Inhibition of PA binding to its receptors, tumor endothelium marker-8 (TEM8) and capillary morphogenesis protein-2 (CMG2) can effectively block anthrax intoxication, which is particularly valuable when the toxin has already been overproduced at the late stage of anthrax infection, thus rendering antibiotics ineffectual.

Shiga toxin type 2 (Stx2), a potential agent of bioterrorism, has a short distribution and a long elimination half-life, and induces kidney and thymus lesions in rats.

Shiga toxin type 2, a major virulence factor produced by the Shiga toxin-producing Escherichia coli, is a potential toxin agent of bioterrorism. In this study, iodine-125 (125I) was used as an indicator to describe the in vivo Stx2 biodistribution profile. The rats were injected intravenously (i.

Qualitative and quantitative studies on human B7.1-Fc fusion protein and the application in pharmacokinetic study in rhesus monkeys.

A sensitive, accurate, and precise enzyme immunoassay (EIA) for the quantification of intact human B7.1-Fc in rhesus monkey serum was validated, and the characteristics of B7.1 and Fc moiety of fusion protein were identified by surface plasmon resonance (SPR) and flow-cytometric method, respectively.

Quantitative analysis of a novel HIV fusion inhibitor (sifuvirtide) in HIV infected human plasma using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry.

A sensitive method for measuring sifuvirtide, a novel HIV fusion inhibitor peptide drug in HIV-1(+) human plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. The plasma samples were treated by solvent/detergent (S/D) method to inactivate viral activity before analysis. After protein precipitation sifuvirtide was determined by LC-MS/MS.

The extract of inflamed rabbit skin induced by inoculation of vaccinia virus possesses antioxidant and neuroprotective effects in acute ischemic stroke.

Acute cerebral ischemia remains a major cause for death and disability but current therapeutic options are limited. A mixture of biological agents extracted from the inflamed rabbit skin induced by inoculation of vaccinia virus has been shown to reduce ischemia-induced cerebral edema in vivo. In the current study we show that treatment with such a mixture can also significantly reduce the infarct volume and ameliorate the neurologic deficits in animals after acute occlusion of the middle cerebral artery.

Development of a rapid and sensitive LC-MS/MS assay for the determination of combretastatin A4 phosphate, combretastatin A4 and combretastatin A4 glucuronide in beagle dog plasma and its application to a pharmacokinetic study.

This study details the development and validation of a simple and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method for the quantification of combretastatin A-4 3-O-phosphate (CA4P), combretastatin A4 (CA4) and its main metabolite, combretastatin A4 glucuronide (CA4G), in beagle dog plasma. Sample pretreatment includes simple protein precipitation by adding methanol to the plasma sample containing an internal standard (colchicine). LC separation was successfully accomplished on a Waters RP8 Symmetryshield column (3.

A new approach for pharmacokinetics of single-dose cetuximab in rhesus monkeys by surface plasmon resonance biosensor.

A novel assay method has been developed and validated, using surface plasmon resonance (SPR), for quantitation of cetuximab (C225) in monkey serum. By injecting non-labeled antibody samples onto a biosensor surface on which epidermal growth factor receptor (EGFR) was immobilized, the concentration of C225 can be accurately measured. This assay has a range of reliable response from 0.

Development and application of a real-time PCR method for pharmacokinetic and biodistribution studies of recombinant adenovirus.

A replication-deficient recombinant adenovirus (Ad5-LFA-3/IgG(1)) that encodes secreted LFA-3/IgG(1) was constructed for gene therapy treatment of psoriasis. The purpose of this study was to develop a real-time PCR method for pharmacokinetic and biodistribution studies of Ad5-LFA-3/IgG(1) within the circulation and organs. This method showed good specificity, sensitivity and reproducibility over a wide dynamic range of concentrations.

Validation of a sensitive gas chromatographic-mass spectrometric method for the simultaneous determination of beta-elemene and beta-elemenal in human plasma.

A sensitive gas chromatographic-mass spectrometric assay was described for determination of beta-elemene and beta-elemenal in human plasma, which has been successfully applied in clinical trial. After liquid-liquid extraction and gas chromatographic separation, the analytes were identified and quantitated. Calibration curves were linear in range from 31.

Single- and multiple-dose pharmacokinetics of exendin-4 in rhesus monkeys.

A radioimmunoassay (RIA) for the measurement of exendin-4 concentration in rhesus monkeys serum was developed and validated. The radioimmunoassay described here was sensitive, linear, accurate, precise, and reproducible. Range of the assay was 25-2000 pg/ml.

Validation of a sensitive LC/MS/MS method for simultaneous quantitation of flupentixol and melitracene in human plasma.

A sensitive method has been developed and validated, using LC/ESI-MS/MS, for simultaneous quantitation of flupentixol and melitracen--antidepressant drugs, in human plasma. The quantitation of the target compounds was determined in a positive ion mode and multiple reaction monitoring (MRM). The method involved a repeated liquid-liquid extraction with diethyl ether and analytes were chromatographed on a C(8) chromatographic column by elution with acetonitrile-water-formic acid (36:64:1, v/v/v) and analyzed by tandem mass spectrometry.