Targeted delivery of alcohol-containing payloads with antibody-drug conjugates.

We herein describe the cell-specific release of alcohol-containing payloads a sulfatase-sensitive linker in antibody-drug conjugates (ADCs). The linker shows efficient sulfatase-mediated release and high stability in human and mouse plasma. evaluation demonstrates potent antigen dependent toxicity towards breast cancer cell lines.

Incorporation of Hydrophilic Macrocycles Into Drug-Linker Reagents Produces Antibody-Drug Conjugates With Enhanced Performance.

Antibody-drug conjugates (ADCs) have begun to fulfil their promise as targeted cancer therapeutics with ten clinical approvals to date. As the field matures, much attention has focused upon the key factors required to produce safe and efficacious ADCs. Recently the role that linker-payload reagent design has on the properties of ADCs has been highlighted as an important consideration for developers.

Modulation of drug-linker design to enhance in vivo potency of homogeneous antibody-drug conjugates.

Antibody-drug conjugates (ADCs) are a promising class of anticancer agents which have undergone substantial development over the past decade and are now achieving clinical success. The development of novel site-specific conjugation technologies enables the systematic study of architectural features within the antibody conjugated drug linker that may affect overall therapeutic indices. Here we describe the results of a systematic study investigating the impact of drug-linker design on the in vivo properties of a series of homogeneous ADCs with a conserved site of conjugation, a monodisperse drug loading, a lysosomal release functionality and monomethyl auristatin E as a cytotoxic payload.

A secretory leukocyte protease inhibitor variant with improved activity against lung infection.

Secretory leukocyte protease inhibitor (SLPI) is an important respiratory tract host defense protein, which is proteolytically inactivated by excessive neutrophil elastase (NE) during chronic Pseudomonas infection in the cystic fibrosis (CF) lung. We generated two putative NE-resistant variants of SLPI by site-directed mutagenesis, SLPI-A16G and SLPI-S15G-A16G, with a view to improving SLPI's proteolytic stability. Both variants showed enhanced resistance to degradation in the presence of excess NE as well as CF patient sputum compared with SLPI-wild type (SLPI-WT).

In Vitro and In Vivo Evaluation of Cysteine Rebridged Trastuzumab-MMAE Antibody Drug Conjugates with Defined Drug-to-Antibody Ratios.

The conjugation of monomethyl auristatin E (MMAE) to trastuzumab using a reduction bis-alkylation approach that is capable of rebridging reduced (native) antibody interchain disulfide bonds has been previously shown to produce a homogeneous and stable conjugate with a drug-to-antibody ratio (DAR) of 4 as the major product. Here, we further investigate the potency of the DAR 4 conjugates prepared by bis-alkylation by comparing to lower drug loaded variants to maleimide linker based conjugates possessing typical mixed DAR profiles. Serum stability, HER2 receptor binding, internalization, in vitro potency, and in vivo efficacy were all evaluated.

A role for whey acidic protein four-disulfide-core 12 (WFDC12) in the regulation of the inflammatory response in the lung.

Introduction: Secretory leucocyte protease inhibitor and elafin are members of the whey acidic protein (WAP), or WAP four disulfide-core (WFDC), family of proteins and have multiple contributions to innate defence including inhibition of neutrophil serine proteases and inhibition of the inflammatory response to lipopolysaccharide (LPS). This study aimed to explore potential activities of WFDC12, a previously uncharacterised WFDC protein expressed in the lung.

Methods: Recombinant expression and purification of WFDC12 were optimised in Escherichia coli.

Bridging disulfides for stable and defined antibody drug conjugates.

To improve both the homogeneity and the stability of ADCs, we have developed site-specific drug-conjugating reagents that covalently rebridge reduced disulfide bonds. The new reagents comprise a drug, a linker, and a bis-reactive conjugating moiety that is capable of undergoing reaction with both sulfur atoms derived from a reduced disulfide bond in antibodies and antibody fragments. A disulfide rebridging reagent comprising monomethyl auristatin E (MMAE) was prepared and conjugated to trastuzumab (TRA).

Stable expression and purification of a functional processed Fab' fragment from a single nascent polypeptide in CHO cells expressing the mCAT-1 retroviral receptor.

Monoclonal antibodies and derivative formats such as Fab' fragments are used in a broad range of therapeutic, diagnostic and research applications. New systems and methodologies that can improve the production of these proteins are consequently of much interest. Here we present a novel approach for the rapid production of processed Fab' fragments in a CHO cell line that has been engineered to express the mouse cationic amino acid transporter receptor 1 (mCAT-1).

Effect of monosodium methanarsonate application on cuticle wax content of cocklebur and cotton plants.

Leaf cuticle waxes were extracted from monosodium methanearsonate (MSMA)-resistant (R) and -susceptible (S) common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) plants at 0, 3, 5, and 7 days after treatment (DAT) following 1x and 2x MSMA applications.

Biological activities of Ginkgo extracts.

The biological activity of methanolic the extracts of leaves, roots, leaf-derived callus, root-derived callus, ginkolide A, ginkgolide B, bilobalide and a commercial Ginkgo product (Tanakan) was assessed. Bioassays consisted of the Agrobacterium tumefaciens-induced potato tumor assay and a Kirby-Bauer microbial sensitivity assay with pure strains of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus pyogenes. Methanolic extracts of leaves, leaf-derived callus, root-derived callus, bilobalide and Tanakan inhibited tumor formation significantly, but more weakly than the positive control, camptothecin.

MSMA resistance studies.

Monosodium methanearsonate (MSMA)-resistant and -susceptible common cocklebur (Xanthium strumarium L.) and cotton (Gossypium hirsutum L.) were treated with MSMA.

Mycotoxins in root extracts of American and Asian ginseng bind estrogen receptors alpha and beta.

The estrogenic activity of ginseng has been the subject of conflicting reports. Cell proliferation, induction of estrogen-responsive genes, and isolated cases of adverse reactions such as postmenopausal vaginal bleeding and gynecomastia have been reported after ginseng treatment. Other studies report antiproliferative effects with no induction of estrogen-responsive genes.

Light and clomazone effects on tobacco (Nicotiana tabacum) callus and leaf discs.

The effects of clomazone on the growth of tobacco (Nicotiana tabacum L. 'NC2326') callus and leaf discs were studied under four light regimes. Callus cultures and leaf discs were grown on Murashige and Skoog medium supplemented with IAA and kinetin.

Potato disc tumor induction assay: a multiple mode of drug action assay.

The study reported herein utilized the Agrobacterium tumefaciens-induced potato disc tumor assay. The objective was to verify the detection of antineoplastic activity in the potato disc tumor induction assay, regardless of the mode of antineoplastic drug action. Camptothecin, paclitaxel, podophyllin, vinblastine and vincristine were tested, each with a different mode of action.

Fate of isoxaben in a containerized plant rhizosphere system.

Commercial production of ornamental plants is an important industry in the United States and involves a complex technology that includes the use of herbicides. Isoxaben[N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide] is a pre-emergence herbicide used for controlling weeds in many areas including containerized ornamental plants. Degradation was studied in potting mix (80% bark, 20% sand) with three different regimes (sterile, bulk and rhizosphere).

Biological activity of common mullein, a medicinal plant.

Common Mullein (Verbascum thapsus L., Scrophulariaceae) is a medicinal plant that has been used for the treatment of inflammatory diseases, asthma, spasmodic coughs, diarrhea and other pulmonary problems. The objective of this study was to assess the biological activity of Common Mullein extracts and commercial Mullein products using selected bench top bioassays, including antibacterial, antitumor, and two toxicity assays--brine shrimp and radish seed.

Atrazine effects on in vitro maturation and in vitro fertilization in the bovine oocyte.

The effect of low levels of atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) on in vitro oocyte maturation, in vitro capacitation of sperm, or in vitro fertilization of bovine oocytes and on the quality of blastocyst formation was studied. Bovine oocytes collected from abattoir ovaries were matured, fertilized, and developed to the blastocyst stage in vitro. Embryos that reached a morula or blastocyst stage were stained with Hoechst 33258 stain to determine the number of blastomeres per embryo.

Degradation of isoxaben in soils and an aqueous system.

The degradation of isoxaben [N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide] was studied in soil and in an aqueous system. Soil studies were conducted in Erlenmeyer flasks (treated with 1 microg/g isoxaben) and mineralization studies in Biometer flasks (treated with 1 microg/g unlabeled and 14C-isoxaben) incubated at 23 C. Degradation in the aqueous system was performed in Erlenmeyer flasks under aerobic and anaerobic conditions incubated at 23 degrees C.

Microbial degradation of mefenoxam in rhizosphere of Zinnia angustifolia.

The fate of the fungicide mefenoxam was studied in a containerized rhizosphere system. The rhizosphere system used Zinnia angustifolia (Tropic Snow) in a bark/sand potting mix and was compared to bulk potting mix (no plants). Rhizosphere microbial populations were allowed to establish for 3 weeks prior to fungicide addition (20 microg per g mix).

Atrazine degradation in a containerized rhizosphere system.

The effect of atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) on rhizosphere microorganisms and its fate in a containerized rhizosphere system was studied. The rhizosphere system consisted of corn grown in pot containing a defined potting mix of sand and bark with atrazine. Sterilized potting mix and a container without plants served as controls.

Growth effects, uptake and metabolism of trifluralin in tissue cultures.

Growth effects, uptake and metabolism of trifluralin (alpha, alpha, alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) in carrot (Daucus carota L.) and tobacco (Nicotiana tabaccum L.) callus tissue were determined.

Degradation of selected phenylurea herbicides by anaerobic pond sediment.

Anaerobic degradation of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], monuron [3-(4-chlorophenyl)-1,1-dimethylurea], and fenuron [1,1-dimethyl-3-phenylurea] were studied. Herbicide containing media (reduced with cysteine-HCl and under 95% N2:5% CO2 gas phase) were inoculated with pond sediments. Sediment from a diuron-treated pond dehalongenated diuron to 3-(3-chlorophenyl)-1,1-dimethylurea (CPDU) in 17 to 25 days but sterile sediment from the pond did not.

Aerobic degradation of diuron by aquatic microorganisms.

Degradation of diuron [3-(3,4-dichlorophenyl)-1,1-dimethyl-urea] by microorganisms obtained from pond water and sediment was determined under aerobic conditions. Enrichment procedures were used to isolate cultures capable of degrading the herbicide. Several mixed fungal/bacterial and mixed bacterial cultures were isolated that could degrade diuron.

Aerobic and anaerobic degradation of profluralin and trifluralin.

The degradation of profluralin [N-(cyclopropylmethyl)-alpha,alpha,alpha-trifluoro-2,6-dinitro-N-propyl-p-toluidine] and trifluralin (alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) was studied under aerobic and anaerobic soil conditions. Three soils (Goldsboro loamy sand, Cecil loamy sand, Drummer clay loam) were each treated with 1 ppmw herbicide; anaerobic conditions were maintained by flooding. Soil samples were extracted monthly and subjected to TLC analysis.