Anti-Quail Tyrosine Hydroxylase Monoclonal antibody, clone 0

Annexin-based probes have long been used to study apoptotic cell death, which is of key importance to many areas of biological research, drug discovery, and clinical applications. Although apoptosis is a dynamic biological event with cell-to-cell variations, current annexin-based probes are impractical for monitoring apoptosis in real-time. Herein, a quenched annexin V-near-infrared fluorophore conjugate (Q-annexin V) is reported as the first OFF-ON annexin protein-based molecular sensor for real-time near-infrared fluorescence imaging of apoptosis. Q-annexin V is non-fluorescent in the extracellular region, due to photoinduced electron transfer interactions between the conjugated dye and amino acid quenchers (tryptophan and tyrosine). The probe becomes highly fluorescent when bound to phosphatidylserines on the outer layer of cell membranes during apoptosis, thereby enabling apoptosis to be monitored in real-time in 2D and 3D cell structures. In particular, Q-annexin V shows superior utility for in vivo apoptosis fluorescence imaging in animal models of cisplatin-induced acute kidney injury and cancer immune therapy, compared to the conventional polarity-sensitive pSIVA-IANBD or annexin V-Alexa647 conjugates.

Gallium-based drugs have been repurposed as antibacterial therapeutic candidates and have shown significant potential as an alternative treatment option against drug resistant pathogens. The activity of gallium (Ga3+) is a result of its chemical similarity to ferric iron (Fe3+) and substitution into iron-dependent pathways. Ga3+ is redox inactive in typical physiological environments and therefore perturbs iron metabolism vital for bacterial growth. Gallium maltolate (GaM) is a well-known water-soluble formulation of gallium, consisting of a central gallium cation coordinated to three maltolate ligands, [Ga(Maltol(-1H))(3)]. This study implemented a label-free quantitative proteomic approach to observe the effect of GaM on the bacterial pathogen, Pseudomonas aeruginosa. The replacement of iron for gallium mimics an iron-limitation response, as shown by increased abundance of proteins associated with iron acquisition and storage. A decreased abundance of proteins associated with quorum-sensing and swarming motility was also identified. These processes are a fundamental component of bacterial virulence and dissemination and hence suggest a potential role for GaM in the treatment of P. aeruginosa infection. [GRAPHICS] .