AuthorsAustin CD, Lawrence DA, Peden AA, Varfolomeev EE, Totpal K, De Mazière AM, Klumperman J, Arnott D, Pham V, Scheller RH, Ashkenazi A
JournalProc Natl Acad Sci U S A
PubMed ID16801533
'Endocytosis is crucial for various aspects of cell homeostasis. Here, we show that proapoptotic death receptors (DRs) trigger selective destruction of the clathrin-dependent endocytosis machinery. DR stimulation induced rapid, caspase-mediated cleavage of key clathrin-pathway components, halting cellular uptake of the classic cargo protein transferrin. DR-proximal initiator caspases cleaved the clathrin ... More
A modular IgG-scFv bispecific antibody topology.
AuthorsOrcutt KD, Ackerman ME, Cieslewicz M, Quiroz E, Slusarczyk AL, Frangioni JV, Wittrup KD,
JournalProtein Eng Des Sel
PubMed ID20019028
'Here we present a bispecific antibody (bsAb) format in which a disulfide-stabilized scFv is fused to the C-terminus of the light chain of an IgG to create an IgG-scFv bifunctional antibody. When expressed in mammalian cells and purified by one-step protein A chromatography, the bsAb retains parental affinities of each ... More
Self-delivering nanoemulsions for dual fluorine-19 MRI and fluorescence detection.
AuthorsJanjic JM, Srinivas M, Kadayakkara DK, Ahrens ET,
JournalJ Am Chem Soc
PubMed ID18266363
We report the design, synthesis, and biological testing of highly stable, nontoxic perfluoropolyether (PFPE) nanoemulsions for dual 19F MRI-fluorescence detection. A linear PFPE polymer was covalently conjugated to common fluorescent dyes (FITC, Alexa647 and BODIPy-TR), mixed with pluronic F68 and linear polyethyleneimine (PEI), and emulsified by microfluidization. Prepared nanoemulsions (<200 ... More
Development and in vivo efficacy of targeted polymeric inflammation-resolving nanoparticles.
AuthorsKamaly N, Fredman G, Subramanian M, Gadde S, Pesic A, Cheung L, Fayad ZA, Langer R, Tabas I, Farokhzad OC,
JournalProc Natl Acad Sci U S A
PubMed ID23533277
Excessive inflammation and failed resolution of the inflammatory response are underlying components of numerous conditions such as arthritis, cardiovascular disease, and cancer. Hence, therapeutics that dampen inflammation and enhance resolution are of considerable interest. In this study, we demonstrate the proresolving activity of sub-100-nm nanoparticles (NPs) containing the anti-inflammatory peptide ... More
Adsorbed proteins influence the biological activity and molecular targeting of nanomaterials.
The possible combination of specific physicochemical properties operating at unique sites of action within cells and tissues has led to considerable uncertainty surrounding nanomaterial toxic potential. We have investigated the importance of proteins adsorbed onto the surface of two distinct classes of nanomaterials (single-walled carbon nanotubes [SWCNTs]; 10-nm amorphous silica) ... More
Whole-cell 3D STORM reveals interactions between cellular structures with nanometer-scale resolution.
AuthorsHuang B, Jones SA, Brandenburg B, Zhuang X,
JournalNat Methods
PubMed ID19029906
The ability to directly visualize nanoscopic cellular structures and their spatial relationship in all three dimensions will greatly enhance our understanding of molecular processes in cells. Here we demonstrated multicolor three-dimensional (3D) stochastic optical reconstruction microscopy (STORM) as a tool to quantitatively probe cellular structures and their interactions. To facilitate ... More
In vivo imaging of membrane-associated glycans in developing zebrafish.
Glycans are attractive targets for molecular imaging but have been inaccessible because of their incompatibility with genetically encoded reporters. We demonstrated the noninvasive imaging of glycans in live developing zebrafish, using a chemical reporter strategy. Zebrafish embryos were treated with an unnatural sugar to metabolically label their cell-surface glycans with ... More
Copper-free click chemistry for dynamic in vivo imaging.
AuthorsBaskin JM, Prescher JA, Laughlin ST, Agard NJ, Chang PV, Miller IA, Lo A, Codelli JA, Bertozzi CR,
JournalProc Natl Acad Sci U S A
PubMed ID17942682
Dynamic imaging of proteins in live cells is routinely performed by using genetically encoded reporters, an approach that cannot be extended to other classes of biomolecules such as glycans and lipids. Here, we report a Cu-free variant of click chemistry that can label these biomolecules rapidly and selectively in living ... More
Site-specific labeling of proteins for single-molecule FRET by combining chemical and enzymatic modification.
AuthorsJäger M, Nir E, Weiss S
JournalProtein Sci
PubMed ID16452617
An often limiting factor for studying protein folding by single-molecule fluorescence resonance energy transfer (FRET) is the ability to site-specifically introduce a photostable organic FRET donor (D) and a complementary acceptor (A) into a polypeptide chain. Using alternating-laser excitation and chymotrypsin inhibitor 2 as a model, we show that chemical ... More