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1.
Scand J Psychol ; 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38009314

ABSTRACT

As organizations have recognized their cause/solution relationship with the environment, increasing attention is being given to the role of employees make in achieving green organizational objectives. Even though, business sustainability initiatives are often led by leaders; employee green behavior (EGB) plays a vital role in success of such initiatives. The current paper focuses on relatively less researched topic of EGB. It uses a narrative review approach to develop a multi-level conceptual framework that draws upon the connectivity of leadership influence at firm and team levels, and how this influences individual level EGB. The paper offers a holistic approach to influencing effective green strategies in organizational contexts. By doing so, it contributes to the larger debate on different dimensions, mechanisms, and levels of environmentally responsible behavior in organizational settings and opens up new avenues for multi-level and cross-layer empirical research.

2.
MethodsX ; 11: 102349, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37680365

ABSTRACT

Glycoproteins are a particularly interesting subset of the cellular proteome as a high proportion of proteins present on the extracellular cell surface are glycosylated. These cell surface proteins are ideal targets for biologic drug therapies or for diagnostics tests. Here, we describe a modification of the well-described Cell Surface Capture (CSC) method for the selective isolation and identification of cell surface glycoproteins that contain N-linked carbohydrates. This modification, which we refer to as Direct Cell Surface Capture (D-CSC), is based on oxidation of cell surface glycans on intact cells, followed by direct conjugation of the oxidized oligosaccharides to a solid support using hydrazide chemistry, with no biotinylation step. As a proof-of-principle, we applied D-CSC to the analysis of cell surface membrane proteins of three adherent cancer cell lines (A549, OVCAR3, and U87MG) and compared our results to those published using the well-established Cell Surface Capture (CSC) method, demonstrating comparable selectivity for cell surface proteins. •A method enabling the identification of cell surface proteins from cells in culture is described.•Application of this method to profile the cell surface on three different cancer cell lines is included.

3.
Methods Mol Biol ; 2549: 345-357, 2022.
Article in English | MEDLINE | ID: mdl-35218529

ABSTRACT

Automated high-throughput immunoassays are emerging as reliable analytic techniques for the quantitative detection of proteins from a variety of sample types. Herein, we describe a method using the Protein Simple Wes capillary-based automated immunoassays platform for the quantification of His- and HA-tagged antibody transcytosis across an in vitro transwell blood-brain barrier (BBB) model. Compared to conventional ELISA, fluorescence, and Mass Spec-based detection approaches, Wes provides comparable datasets with additional information regarding size, aggregation, and potential degradation of samples before and after BBB transcytosis. In this chapter, we have benchmarked our Wes technique against ELISA and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), using known BBB crossing (FC5) and non-crossing (A20.1) single domain antibodies.


Subject(s)
Blood-Brain Barrier , Endothelial Cells , Antibodies/chemistry , Blood-Brain Barrier/metabolism , Chromatography, Liquid , Endothelial Cells/metabolism , Enzyme-Linked Immunosorbent Assay , Immunoassay , Tandem Mass Spectrometry , Transcytosis
4.
Immunol Cell Biol ; 97(6): 526-537, 2019 07.
Article in English | MEDLINE | ID: mdl-30680791

ABSTRACT

Human IgG1 and IgG3 antibodies (Abs) can mediate Ab-dependent cellular cytotoxicity (ADCC), and engineering of the Ab Fc (point mutation; defucosylation) has been shown to affect ADCC by modulating affinity for FcRγIIIa. In the absence of a CH 1 domain, many camelid heavy-chain Abs (HCAbs) naturally bear very long and flexible hinge regions connecting their VH H and CH 2 domains. To better understand the influence of hinge length and structure on HCAb ADCC, we produced a series of hinge-engineered epidermal growth factor receptor (EGFR)-specific chimeric camelid VH H-human Fc Abs and characterized their affinities for recombinant EGFR and FcRγIIIa, their binding to EGFR-positive tumor cells, and their ability to elicit ADCC. In the case of one chimeric HCAb (EG2-hFc), we found that variants bearing longer hinges (IgG3 or camelid hinge regions) showed dramatically improved ADCC in comparison with a variant bearing the human IgG1 hinge, in similar fashion to a variant with reduced CH 2 fucosylation. Conversely, an EG2-hFc variant bearing a truncated human IgG1 upper hinge region failed to elicit ADCC. However, there was no consistent association between hinge length and ADCC for four similarly engineered chimeric HCAbs directed against distinct EGFR epitopes. These findings demonstrate that the ADCC of some HCAbs can be modulated simply by varying the length of the Ab hinge. Although this effect appears to be heavily epitope-dependent, this strategy may be useful to consider during the design of VH H-based therapeutic Abs for cancer.


Subject(s)
Adenocarcinoma/therapy , Antibodies, Monoclonal/metabolism , Breast Neoplasms/therapy , Immunotherapy/methods , Recombinant Fusion Proteins/genetics , Adenocarcinoma/immunology , Animals , Antibodies, Monoclonal/genetics , Antibody Affinity , Antibody-Dependent Cell Cytotoxicity , Breast Neoplasms/immunology , Camelidae , Cell Line, Tumor , ErbB Receptors/immunology , ErbB Receptors/metabolism , Female , Humans , Immunoglobulin Fc Fragments/genetics , Immunoglobulin G/genetics , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Variable Region/genetics , Mutation/genetics , Protein Binding , Protein Engineering
5.
Biochem J ; 476(1): 39-50, 2019 01 07.
Article in English | MEDLINE | ID: mdl-30455372

ABSTRACT

Up-regulation of epidermal growth factor receptor (EGFR) is a hallmark of many solid tumors, and inhibition of EGFR signaling by small molecules and antibodies has clear clinical benefit. Here, we report the isolation and functional characterization of novel camelid single-domain antibodies (sdAbs or VHHs) directed against human EGFR. The source of these VHHs was a llama immunized with cDNA encoding human EGFR ectodomain alone (no protein or cell boost), which is notable in that genetic immunization of large, outbred animals is generally poorly effective. The VHHs targeted multiple sites on the receptor's surface with high affinity (KD range: 1-40 nM), including one epitope overlapping that of cetuximab, several epitopes conserved in the cynomolgus EGFR orthologue, and at least one epitope conserved in the mouse EGFR orthologue. Interestingly, despite their generation against human EGFR expressed from cDNA by llama cells in vivo (presumably in native conformation), the VHHs exhibited wide and epitope-dependent variation in their apparent affinities for native EGFR displayed on tumor cell lines. As fusions to human IgG1 Fc, one of the VHH-Fcs inhibited EGFR signaling induced by EGF binding with a potency similar to that of cetuximab (IC50: ∼30 nM). Thus, DNA immunization elicited high-affinity, functional sdAbs that were vastly superior to those previously isolated by our group through protein immunization.


Subject(s)
Antibodies, Monoclonal/immunology , Camelids, New World/immunology , DNA/pharmacology , Immunization , Single-Domain Antibodies/immunology , Animals , Cell Line, Tumor , DNA/immunology , ErbB Receptors/genetics , ErbB Receptors/immunology , HEK293 Cells , Humans , Male
6.
Mol Pharm ; 15(4): 1420-1431, 2018 04 02.
Article in English | MEDLINE | ID: mdl-29485883

ABSTRACT

The blood-brain barrier (BBB) is a formidable obstacle for brain delivery of therapeutic antibodies. However, antibodies against the transferrin receptor (TfR), enriched in brain endothelial cells, have been developed as delivery carriers of therapeutic cargoes into the brain via a receptor-mediated transcytosis pathway. In vitro and in vivo studies demonstrated that either a low-affinity or monovalent binding of these antibodies to the TfR improves their release on the abluminal side of the BBB and target engagement in brain parenchyma. However, these studies have been performed with mouse-selective TfR antibodies that recognize different TfR epitopes and have varied binding characteristics. In this study, we evaluated serum pharmacokinetics and brain and CSF exposure of the rat TfR-binding antibody OX26 affinity variants, having KDs of 5 nM, 76 nM, 108 nM, and 174 nM, all binding the same epitope in bivalent format. Pharmacodynamic responses were tested in the Hargreaves chronic pain model after conjugation of OX26 affinity variants with the analgesic and antiepileptic peptide, galanin. OX26 variants with affinities of 76 nM and 108 nM showed enhanced brain and cerebrospinal fluid (CSF) exposure and higher potency in the Hargreaves model, compared to a 5 nM affinity variant; lowering affinity to 174 nM resulted in prolonged serum pharmacokinetics, but reduced brain and CSF exposure. The study demonstrates that binding affinity optimization of TfR-binding antibodies could improve their brain and CSF exposure even in the absence of monovalent TfR engagement.


Subject(s)
Antibodies, Monoclonal/chemistry , Brain/drug effects , Galanin/chemistry , Receptors, Transferrin/chemistry , Receptors, Transferrin/metabolism , Animals , Antibodies, Monoclonal/metabolism , Antibody Affinity/physiology , Bioengineering/methods , Blood-Brain Barrier/metabolism , Brain/metabolism , Cerebrospinal Fluid/metabolism , Galanin/metabolism , Male , Protein Transport/physiology , Rats , Rats, Sprague-Dawley
7.
J Ir Dent Assoc ; 53(2): 92-5, 2007.
Article in English | MEDLINE | ID: mdl-17685059

ABSTRACT

This article sets out guidelines on the use of bitewing radiographs for the detection of dental caries, with suggested risk factors and recall intervals. It describes a case in which extensive carious lesions were not detected clinically, but were revealed when radiographs were taken during an orthodontic assessment.


Subject(s)
Dental Caries/diagnostic imaging , Practice Guidelines as Topic , Radiography, Bitewing/standards , Adolescent , Cariostatic Agents/metabolism , Female , Fluorides/metabolism , Humans , Orthodontics, Corrective , Referral and Consultation , Societies, Dental , United Kingdom
8.
Biochem Biophys Res Commun ; 342(3): 791-9, 2006 Apr 14.
Article in English | MEDLINE | ID: mdl-16499873

ABSTRACT

Okadaic acid (OA) is a widely used small-molecule phosphatase inhibitor that is thought to selectively inhibit protein phosphatase 2A (PP2A). Multiple studies have demonstrated that PP2A activity is compromised in the brains of Alzheimer's disease patients. Thus, we set out to determine changes in phosphorylation that occur upon OA treatment of neuronal cells. Utilizing isotope-coded affinity tags and mass spectrometry analysis, we determined the relative abundance of proteins in a phosphoprotein enriched fraction from control and OA-treated primary cortical neurons. We identified many proteins whose phosphorylation state is regulated by OA, including glycogen synthase kinase 3beta, collapsin-response mediator proteins (DRP-2, DPYSL-5, and CRMP-4), and the B subunit of PP2A itself. Most interestingly, we have found that complexin 2, an important regulator of neurotransmitter release and synaptic plasticity, is phosphorylated at serine 93 upon OA treatment of neurons. This is the first report of a phosphorylation site on complexin 2.


Subject(s)
Okadaic Acid/pharmacology , Phosphoproteins/analysis , Amino Acid Sequence , Animals , Cells, Cultured , Mass Spectrometry , Molecular Sequence Data , Nerve Tissue Proteins/analysis , Phosphoprotein Phosphatases/metabolism , Phosphoproteins/chemistry , Phosphorylation/drug effects , Protein Phosphatase 2 , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Research Design , tau Proteins/analysis
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